The scientific journal Food Chemistry publishes original research papers dealing with the advancement of the chemistry and biochemistry of foods or the analytical methods/approach used. All papers should focus on the novelty of the research carried out.
Topics include: Chemistry relating to major and minor components of food, their nutritional, physiological, sensory, flavour and microbiological aspects; bioactive constituents; effects of processing; chemistry of food additives, contaminants etc.
The publisher is the Elsevier. The copyright and publishing rights of specialized products listed below are in this publishing house. This is also responsible for the content shown.
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Additional research articles in the field of food chemistry, see Current Chemistry Research Articles. Magazines with similar content:
- Food & Function.
- Journal of Agricultural and Food Chemistry.
Food Chemistry - Abstracts
In vitro health promoting properties of antioxidant dietary fiber extracted from spent coffee (Coffee arabica L.) grounds
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Kenia Vázquez-Sánchez, Nuria Martinez-Saez, Miguel Rebollo-Hernanz, Maria Dolores del Castillo, Marcela Gaytán-Martínez, Rocio Campos-Vega
Antioxidant dietary fiber extracted from spent coffee grounds (FSCG) was evaluated as a potential functional food ingredient when incorporated in a food model (biscuits), and digested in vitro under simulated human gastrointestinal conditions. FSCG added to biscuits increased its total dietary fiber, antioxidant capacity after in vitro digestion, bioaccessibility of phenolic compounds (gallic acid and catechin) and amino acids. Furthermore, advanced glycation end products (AGEs), involved in chronic diseases, decreased up to 6-folds in the biscuits containing FSCG when compared with the traditional biscuit. The digestible fraction of biscuits containing the highest amount of FSCG (5 g) displayed the higher inhibiting α-glucosidase activity, correlating with the bioaccessibility of ascorbic acid and catechin. Our study seems to indicate that anti-diabetic compounds may be released in the small intestine during FSCG digestion, where biscuits containing FSCG may be able to beneficially regulate sugar metabolism thereby helping in producing foods friendly for diabetes.
Datum: 25.04.2018
Cloning, characterization and substrate degradation mode of a novel chitinase from Streptomyces albolongus ATCC 27414
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Li Gao, Jianan Sun, Francesco Secundo, Xin Gao, Changhu Xue, Xiangzhao Mao
A novel chitinase gene was cloned from Streptomyces albolongus ATCC 27414, and expressed successfully in Escherichia coli BL21. The recombinant enzyme (SaChiA4) belongs to glycoside hydrolases (GH) family 18 and consists of a catalytic domain and a chitin binding domain (CBD) in its C-terminus. SaChiA4 was purified homogeneously (specific activity of 66.2 U/mg with colloidal chitin as substrate), and showed a molecular mass of approximately 47 kDa. SaChiA4 showed its optimal activity at pH 5.0 and 55 °C and exhibited remarkable pH and temperature stability. SaChiA4 has been proved to have a higher specificity toward glycosides containing acetyl groups and hydrolyzes the substrates in a non-processive manner with higher ability to produce (GlcNAc)2 and GlcNAc. The results indicated that SaChiA4 is a novel endo-type chitinase, which has potential applications in the treatment of chitin wastes and the production of (GlcNAc)2.Graphical abstract
Datum: 25.04.2018
Phenolic and triterpenoid composition and inhibition of α-amylase of pistachio kernels (Pistacia vera L.) as affected by rootstock and irrigation treatment
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Luis Noguera-Artiaga, David Pérez-López, Armando Burgos-Hernández, Aneta Wojdyło, Ángel A. Carbonell-Barrachina
The current water scarcity forces farmers to adopt new irrigation strategies to save water without jeopardizing the fruit yield and quality. In this study, the influence of 3 regulated deficit irrigation (RDI) treatments and 3 rootstocks on the functional quality of pistachios were studied. The functional parameters studied included, polyphenols, triterpenoids, and inhibition of α-amylase. The results showed that P. terebinthus and P. atlantica rootstocks led to pistachio kernels with higher contents of polyphenols and triterpenoids (mainly betulinic acid with 111 and 102 µg g−1, respectively) than pistachios obtained using P. integerrima rootstock (81 µg g−1). On the other hand, the use of moderate RDI (T1 treatment) increased the total content of polyphenols (∼10%), quercetin-O-galloyl-hexoside (∼15%), keampferol-3-O-glucoside (∼19%), and polymeric procyanidins (∼20%), as compared to the control trees, resulting in pistachios with a better functional profile, lower economic cost and with a lesser environmental impact.
Datum: 25.04.2018
Characterization of food additive-potato starch complexes by FTIR and X-ray diffraction
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Author(s): Iman Dankar, Amira Haddarah, Fawaz E.L. Omar, Montserrat Pujolà, Francesc Sepulcre
Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) techniques were used to study the effect of four food additives, agar, alginate, lecithin and glycerol, at three different concentrations, 0.5, 1 and 1.5%, on the molecular structure of potato puree prepared from commercial potato powder. Vibrational spectra revealed that the amylose-amylopectin skeleton present in the raw potato starch was missing in the potato powder but could be fully recovered upon water addition when the potato puree was prepared. FTIR peaks corresponding to water were clearly present in the potato powder, indicating the important structural role of water molecules in the recovery of the initial molecular conformation.None of the studied puree samples presented a crystalline structure or strong internal order. A comparison of the FTIR and XRD results revealed that the additives exerted some effects, mainly on the long-range order of the starch structure via interacting with and changing –OH and hydrogen bond interactions.
Datum: 25.04.2018
Residue dissipation and risk assessment of tebuconazole, thiophanate-methyl and its metabolite in table grape by liquid chromatography-tandem mass spectrometry
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Author(s): Bizhang Dong, Yuanping Yang, Nannan Pang, Jiye Hu
An efficient method was developed and validated for simultaneous determination of tebuconazole, thiophanate-methyl and its metabolite carbendazim in grape and soil using QuEChERS procedure and liquid chromatography-tandem mass spectrometry. The average recoveries of the method were 83.2%–105.4%, the limit of detection (LOD) ranged from 2.1 × 10−5 to 8.7 × 10−4 mg L−1, and the limit of quantitation (LOQ) was 0.1 mg kg−1. The field results showed that tebuconazole and thiophanate-methyl in soil and grape were rapidly dissipated with half-lives less than 24.7 days. The terminal residues of all analytes in grape were lower than the maximum residue limit (MRL) set by China (2 mg kg−1 for tebuconazole; 3 mg kg−1 for both thiophanate-methyl and carbendazim). Risk assessment showed that tebuconazole, thiophanate-methyl and its metabolite would be unlikely to cause health problems. However, carbendazim, the higher active metabolites of thiophanate-methyl, should receive more concerns.
Datum: 25.04.2018
Comparison of methylation methods for fatty acid analysis of milk fat
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Zhiqian Liu, Vilnis Ezernieks, Simone Rochfort, Ben Cocks
Three acid- and alkaline-catalysed transesterification methods were compared with the aim to validate a simple yet reliable protocol for fatty acid (FA) profiling of milk fat. While both the acid- and alkaline-catalysed methods were able to convert completely triglycerides and phospholipids into fatty acid methyl esters (FAMEs), the acid catalyst caused significant degradation of conjugated linoleic acid C18:2c9t11 at high temperature. Although a milder temperature can mitigate this negative impact, a long reaction time (2 h) is required to achieve full methylation. By contrast, despite being unable to methylate free fatty acids (FFA), the alkaline-catalysed transesterification yielded comparable results for all major FA due to the very low level of FFA in milk. The alkaline-catalysed methylation is benign for C18:2c9t11. We recommend here a simple one-step protocol based on 0.2 M methanolic KOH, a short reaction time (20 min) and a mild reaction temperature (50 °C) for milk FAME preparation.
Datum: 25.04.2018
Identification and hydrolysis kinetic of a novel antioxidant peptide from pecan meal using Alcalase
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Fei Hu, Ao-Te Ci, Hao Wang, Yuan-Yuan Zhang, Jian-Guo Zhang, Kiran Thakur, Zhao-Jun Wei
In this study, the hydrolysis of a pecan protein isolate (PPI) with Alcalase was carried out to generate antioxidant peptides. We proposed a kinetic model to illustrate the enzymolysis process of PPI, which was found suitable for depiction of the kinetic behavior for PPI hydrolysis by Alcalase. The PPI hydrolysis products were gradually fractionated by ultrafiltration through cut-off membranes with molecular weights of 10, 5 and 3 kDa and their antioxidant activities were evaluated in vitro. Further, the strongest antioxidant fraction (<3 kDa) and novel antioxidative peptide were successfully purified. The amino acid sequence of the purified peptide was identified as LAYLQYTDFETR. The purified fraction exhibited appreciable scavenging activities on ABTS radical (67.67%), DPPH radical (56.25%) and hydroxyl radical (47.42%) at 0.1 mg/mL. The results suggested that this novel peptide may serve as a potential antioxidant and it should be evaluated for development of functional foods and pharmaceuticals products.
Datum: 25.04.2018
Isolation and characterization of peptides with dipeptidyl peptidase IV (DPPIV) inhibitory activity from natto using DPPIV from Aspergillus oryzae
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Kousuke Sato, Syogo Miyasaka, Akira Tsuji, Hiroshi Tachi
Human-derived dipeptidyl peptidase IV (DPPIV) is a costly material used in the discovery of drugs for diabetes. In this study, we demonstrated the efficacy of DPPIV from Aspergillus oryzae as an alternative to human-derived DPPIV for identifying DPPIV inhibitors. Fermented soybean, also called natto, suppresses blood glucose levels in humans; however, the underlying mechanism remains unknown. This study determined the in vitro DPPIV inhibitory activity of isolated peptides from natto. Amino acid sequences of two peptides isolated from natto were identified by LC/MS/MS as Lys-Leu and Leu-Arg. These isolated peptides inhibited DPPIV in a dose-dependent manner, with IC50 values of 41.40 ± 2.68 and 598.02 ± 18.35 μg/ml, respectively. These results indicate the potential mechanism of blood glucose control by natto and novel roles of Lys-Leu and Leu-Arg as DPPIV inhibitors.
Datum: 25.04.2018
The major glucosinolate hydrolysis product in rocket (Eruca sativa L.), sativin, is 1,3-thiazepane-2-thione: Elucidation of structure, bioactivity, and stability compared to other rocket isothiocyanates
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Jana Fechner, Martin Kaufmann, Corinna Herz, Daniela Eisenschmidt, Evelyn Lamy, Lothar W. Kroh, Franziska S. Hanschen
Rocket is rich in glucosinolates and valued for its hot and spicy taste. Here we report the structure elucidation, bioactivity, and stability of the mainly formed glucosinolate hydrolysis product, namely sativin, which was formerly thought to be 4-mercaptobutyl isothiocyanate. However, by NMR characterization we revealed that sativin is in fact 1,3-thiazepane-2-thione, a tautomer of 4-mercaptobutyl isothiocyanate with 7-membered ring structure and so far unknown. This finding was further substantiated by conformation sampling using molecular modeling and total enthalpy calculation with density functional theory. During aqueous heat treatment sativin in general was quite stable, while the isothiocyanates erucin and sulforaphane were labile, having half-lives of 132 min and 56 min (pH 5, 100 °C), respectively. Moreover, using a WST-1 assay, we found that sativin did not reduce cell viability of HepG2 cells in a range of 0.3–30 µM, and, therefore, exhibited no cytotoxic effects in this cell line.
Datum: 25.04.2018
Improved chemical stability and cellular antioxidant activity of resveratrol in zein nanoparticle with bovine serum albumin-caffeic acid conjugate
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Yuting Fan, Yuexiang Liu, Luyu Gao, Yuzhu Zhang, Jiang Yi
In this study, bovine serum albumin (BSA)-caffeic acid (CA) conjugate was prepared with free radical-induced grafting method. The CA to BSA ratio of the conjugate was 115.7 mg/g. In vitro antioxidant activity assays suggested that BSA-CA conjugates had stronger antioxidant activity than BSA. Resveratrol-loaded zein encapsulated with BSA and BSA-CA conjugate core-shell nanoparticles were prepared with antisolvent method. Particle sizes were 206.3 nm, and 217.2 nm for BSA and BSA-CA, respectively. The encapsulation efficiencies (EEs) were 85.3% and 86.5% for zein-BSA and zein-BSA-CA nanoparticles, respectively. SEM results indicated that both nanoparticles were spherical with mean diameter approximately 200 nm and smooth surfaces. Both thermal and UV light stability of resveratrol was significantly improved after nanoencapsulation. BSA-CA conjugate showed remarkably greater protection than BSA against resveratrol degradation. Cellular antioxidant activity (CAA) study confirmed that resveratrol in both zein-BSA and zein-BSA-CA nanoparticles had significant higher antioxidant activities than resveratrol alone.
Datum: 25.04.2018
Chemical composition, antifungal activity and potential anti-virulence evaluation of the Eugenia uniflora essential oil against Candida spp.
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Joycy Francely Sampaio dos Santos, Janaína Esmeraldo Rocha, Camila Fonseca Bezerra, Maria Karollyna do Nascimento Silva, Yedda Maria Lobo Soares de Matos, Thiago Sampaio de Freitas, Antonia Thassya Lucas dos Santos, Rafael Pereira da Cruz, Antonio Júdson Targino Machado, Tigressa Helena Soares Rodrigues, Edy Sousa de Brito, Dédora Lima Sales, Waltécio de Oliveira Almeida, José Galberto Martins da Costa, Henrique Douglas Melo Coutinho, Maria Flaviana Bezerra Morais-Braga
The development of fungal resistance to antifungal drugs has been worsening over the years and as a result research on new antifungal agents derived from plants has intensified. Eugenia uniflora L. (pitanga) has been studied for its various biological actions. In this study the chemical composition and antifungal effects of the E. uniflora essential oil (EULEO) were investigated against Candida albicans (CA), Candida krusei (CK) and Candida tropicalis (CT) standard strains. The essential oil obtained through hydro-distillation was analyzed by gas chromatography coupled to mass spectrometry (GC-MS). To determine the IC50 of the oil, the cellular viability curve and the inhibitory effects were measured by means of the oil’s association with Fluconazole in a broth microdilution assay with spectrophotometric readings. The Minimum Fungicidal Concentration (MFC) was determined by solid medium subculture with the aid of a guide plate while the assays used to verify morphological changes emerging from the action of the fractions were performed in microculture chambers at concentrations based on the microdilution. Two major oil constituents stand out from the chemical analysis: selina-1,3,7(11)-trien-8-one (36.37%) and selina-1,3,7(11)-trien-8-one epoxide (27.32%). The concentration that reduced microorganismal growth was ≥8,192 μg/mL while the IC50 varied, this being between 1892.47 and 12491.80 μg/mL (oil), 10.07 – 80.78 μg/mL (fluconazole) and 18.53 – 295.60 μg/mL (fluconazole + oil). The combined activity (fluconazole + oil) resulted in indifference and antagonism. A MFC of the oil in association with fluconazole was recorded at the concentration of 8,192 μg/mL against CA and CK. The oil caused the inhibition of CA and CT morphological transition. In view of the results obtained, additional research is needed to elucidate the activity of the E. uniflora oil over genetic and biochemical processes regarding its effect on Candida spp. virulence.
Datum: 25.04.2018
Acrylamide content in French fries prepared in households: A pilot study in Spanish homes
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Author(s): Marta Mesias, Cristina Delgado-Andrade, Francisca Holgado, Francisco J. Morales
An observational cross-sectional pilot study in 73 Spanish households was conducted to evaluate the impact of consumer practices on the formation of acrylamide during the preparation of French fries from fresh potatoes applying one stage frying. 45.2% of samples presented acrylamide concentrations above the benchmark level for French fries (500 µg/kg). 6.9% of samples exceeded 2000 µg/kg and the 95th percentile was 2028 µg/kg. The median and average values were significantly higher than the EFSA report for this food category, suggesting that the total exposure to acrylamide by the population could be underestimated. In this randomised scenario of cooking practices, the content of reducing sugar and asparagine did not explain the acrylamide levels. However, the chromatic parameter a∗ of the fried potato was a powerful tool to classify the samples according to the acrylamide benchmark level regardless of the agronomical characteristics of the potato or the consumer practices.
Datum: 25.04.2018
Structural characteristics and rheological properties of ovalbumin-gum arabic complex coacervates
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Author(s): Fuge Niu, Mengxuan Kou, Jiamei Fan, Weichun Pan, Zhi-Juan Feng, Yujie Su, Yanjun Yang, Wenhua Zhou
After formation of the ovalbumin (OVA)-gum arabic (GA) complex coacervates, a more ordered crystal structure was obtained, and the protein denaturation temperature increased from 72 to 96 °C. GA can reduce the pH-induced conformational perturbations of ovalbumin. The presence of GA improved the stability of the α-helix and β-turn regions against pH, but showed less influence on the random coil and β-sheet domains. The complex coacervates showed the highest viscosity value at pH 3.7 compared with the other pH values tested (4.0, 3.4, 3.0, 2.7) due to the stronger interactions of OVA and GA. A large thixotropic loop was observed for the coacervate obtained at pH 3.7 compared with that obtained at pH 4.0. Moreover, the salt concentration and OVA:GA ratio influenced the rheological properties by affecting the structure and composition of the complexes. A stronger interaction between OVA and GA led to greater viscoelastic properties.
Datum: 25.04.2018
Bioactive evaluation and application of different formulations of the natural colorant curcumin (E100) in a hydrophilic matrix (yogurt)
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Heloísa H.S. Almeida, Lillian Barros, João C.M. Barreira, Ricardo C. Calhelha, Sandrina A. Heleno, Claudia Sayer, Cristiane Grella Miranda, Fernanda Vitória Leimann, Maria Filomena Barreiro, Isabel C.F.R. Ferreira
Curcumin (E100) is a natural colorant that, besides conferring color, has bioactivity, serving as an alternative to some artificial colorants. As a hydrophobic colorant, its modification/compatibilization with the aqueous medium is required to improve stability and enable its application in hydrophilic food matrices. Herein, different formulations of curcumin (curcumin powder: PC, water-dispersible curcumin: DC: and nanoencapsulated curcumin: NC) were evaluated as yogurt colorants. PC showed the strongest bioactivity in all assays (EC50 values: 63 ± 2 to 7.9 ± 0.1 μg.mL−1; GI50 values: 48 ± 1 to 17 ± 1 μg.mL−1 and MIC values: 0.0625 to 0.5 mg.mL−1), which might indicate that DC and NC reduce the short-term accessibility to curcumin. The tested curcumin formulations produced yogurts with different appearance, specifically associated with their color parameters, besides presenting slight changes in nutritional composition and free sugars and fatty acids profiles. The water compatible formulations (DC and NC) showed advantages over hydrophobic (PC) having a wider industrial utilization.
Datum: 25.04.2018
Antioxidant activity of resveratrol ester derivatives in food and biological model systems
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Won Young Oh, Fereidoon Shahidi
Resveratrol (R) was lipophilized by esterification in order to facilitate its application in a wide range of products and to possibly enhance its bioactivity. Twelve resveratrol derivatives were prepared using acyl chlorides of different chain length (C3:0–C22:6) and their antioxidant activities assessed. While resveratrol showed the highest antioxidant activity in oil-in-water emulsion, its derivatives (RC6:0, RC8:0, RC10:0, RC12:0, RC16:0) showed better antioxidant activity in a bulk oil system. Resveratrol esters RC20:5n-3 (REPA) and RC22:6n-3 (RDHA) showed the highest antioxidant activity when added to ground meat. Meanwhile, resveratrol derivatives (RC3:0–RC14:0) had better hydrogen peroxide scavenging activity than resveratrol. All test compounds except resveratrol and REPA inhibited copper-induced LDL oxidation. Moreover, test compounds effectively inhibited hydroxyl radical induced DNA scission. These results suggest that resveratrol derivatives could potentially serve as functional food ingredients and supplements for health promotion and disease risk reduction.
Datum: 25.04.2018
A comparative study of partial dealcoholisation versus early harvest: Effects on wine volatile and sensory profiles
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Rocco Longo, John W. Blackman, Guillaume Antalick, Peter J. Torley, Suzy Y. Rogiers, Leigh M. Schmidtke
Two Verdelho and Petit Verdot wines were produced from sequential harvests of grapes. The alcohol concentration of early harvest (EH) and late harvest (LH) wines were respectively 9% and 13.5% v/v for Verdelho, and 10.5% and 13% v/v for Petit Verdot. LH wines were dealcoholised to match the same alcohol level of EH samples using a combined reverse osmosis-evaporative perstraction process. In dealcoholised wines, there was a decrease in volatile compounds (esters particularly) compared to LH treatments. For both varieties, the sensory attribute ratings for overall aroma intensity and alcohol mouthfeel also decreased following dealcoholisation. Dealcoholised wines were distinctively different from both LH and EH wines even though these wines had similar alcohol level to EH wines. When dealcoholisation is considered for high-alcohol wines, it is important to consider that membrane effects can significantly change depending on the wine non-volatile matrix composition and the level of alcohol reduction required.
Datum: 25.04.2018
Comparative proteomics analysis of human and ruminant milk serum reveals variation in protection and nutrition
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Jing Lu, Shuwen Zhang, Lu Liu, Xiaoyang Pang, Changlu Ma, Shilong Jiang, Jiaping Lv
In present study, 198, 169, 213 and 128 proteins were identified and quantified in human, cow, goat and yak milk serum respectively by using proteomics techniques. Large variations were observed between human and ruminant milk proteins. Human milk contained higher concentration of mucosal immune response, complement proteins and regulators. The concentration of bactericidal proteins were relatively higher in ruminants milk. Human milk exclusively expressed proteins important for delivery or utilization of nutrients. Peptidase inhibitors prevent the bioactive proteins/peptides in human milk from gastral-intestinal digestion. Protein composition among ruminants milk was similar but with variations. Goat milk contained high level of complement proteins but low level of corresponding regulators. In addition, the acute phase proteins were significantly higher in goat milk. Of note, osteopontin in yak milk was enriched, which could offer an alternative source for producing osteopontin and revealed possible nutritional value of yak milk.
Datum: 25.04.2018
Combination of complementary data mining methods for geographical characterization of extra virgin olive oils based on mineral composition
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Ana Sayago, Raúl González-Domínguez, Rafael Beltrán, Ángeles Fernández-Recamales
This work explores the potential of multi-element fingerprinting in combination with advanced data mining strategies to assess the geographical origin of extra virgin olive oil samples. For this purpose, the concentrations of 55 elements were determined in 125 oil samples from multiple Spanish geographic areas. Several unsupervised and supervised multivariate statistical techniques were used to build classification models and investigate the relationship between mineral composition of olive oils and their provenance. Results showed that Spanish extra virgin olive oils exhibit characteristic element profiles, which can be differentiated on the basis of their origin in accordance with three geographical areas: Atlantic coast (Huelva province), Mediterranean coast and inland regions. Furthermore, statistical modelling yielded high sensitivity and specificity, principally when random forest and support vector machines were employed, thus demonstrating the utility of these techniques in food traceability and authenticity research.
Datum: 25.04.2018
NIR spectroscopy for the quality control of Moringa oleifera (Lam.) leaf powders: Prediction of minerals, protein and moisture contents
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Catherine Rébufa, Inès Pany, Isabelle Bombarda
A rapid methodology was developed to simultaneously predict water content and activity values (aw) of Moringa oleifera leaf powders (MOLP) using near infrared (NIR) signatures and experimental sorption isotherms. NIR spectra of MOLP samples (n = 181) were recorded. A Partial Least Square Regression model (PLS2) was obtained with low standard errors of prediction (SEP of 1.8% and 0.07 for water content and aw respectively). Experimental sorption isotherms obtained at 20, 30 and 40 °C showed similar profiles. This result is particularly important to use MOLP in food industry. In fact, a temperature variation of the drying process will not affect their available water content (self-life). Nutrient contents based on protein and selected minerals (Ca, Fe, K) were also predicted from PLS1 models. Protein contents were well predicted (SEP of 2.3%). This methodology allowed for an improvement in MOLP safety, quality control and traceability.
Datum: 25.04.2018
Molecular forces and gelling properties of heat-set whole chicken egg protein gel as affected by NaCl or pH
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Junhua Li, Mengqi Zhang, Cuihua Chang, Luping Gu, Ning Peng, Yujie Su, Yanjun Yang
Effects of NaCl concentrations and pH on the intermolecular forces and gel properties of whole chicken egg protein dispersions were studied via solubility, surface hydrophobicity, intermolecular forces, texture analysis, low-field nuclear magnetic resonance (LF-NMR) and colour analysis. Results showed that the intermolecular forces involved in the formation of egg gel were regulated by NaCl/pH. The results of gel fracture analysis suggested that the changes of fracture strength and strain were closely related with the internal balance of gel molecular forces. Moreover, a negative/positive correlation existed in the free water/bound water relaxation proportion and fracture strength. These findings provide an important theoretical basis for the innovation of heat-induced egg gel products.
Datum: 25.04.2018
Editorial Board
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Datum: 25.04.2018
Absolute quantification of two antimicrobial peptides αS2-casein182–207 and αS2-casein151–181 in bovine milk by UHPLC–ESI–MS/MS in sMRM mode
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Yufang Liu, Monika Pischetsrieder
To evaluate if the recently identified antimicrobial milk peptides αS2-casein182–207 and αS2-casein151–181 can be of physiological or technological relevance, their presence in commercial milk was investigated. Thus, a UHPLC–ESI–MS/MS scheduled multiple reaction monitoring method was developed for quantification using stable isotope-labeled peptides. The developed protocol gave very good linear response (R2 > 0.99) for both peptides, recovery >95% and coefficients of variations of 5.51% and 4.79%. The limits of detection (0.3 nM αS2-casein182–207 and 0.5 nM αS2-casein151–181) were low enough to detect both peptides without further enrichment. The highest peptide concentration was recorded in pasteurized milk (1.36 μM αS2-casein182–207 and 0.20 μM αS2-casein151–181). The concentration of αS2-casein182–207 was in a range that was previously reported to act bacteriostatic against Bacillus subtilis. Industrial milk processing led to a significant loss of both peptides resulting in a mean concentration of 0.47 µM αS2-casein182–207 and 0.098 µM αS2-casein151–181 in ultrahigh-temperature milk.
Datum: 25.04.2018
Impact of oligomeric procyanidins on wheat gluten microstructure and physicochemical properties
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Author(s): Rui Liu, Chunyue Shi, Yingshi Song, Tao Wu, Min Zhang
We found that oligomeric procyanidins improve the physicochemical properties of wheat flour, and that a more compact and denser gluten microstructure is formed when an increasing amount of oligomeric procyanidins is incorporated. Further, we found that oligomeric procyanidins alter the rheological properties, molecular weight distribution, secondary structure, and thermal stability of gluten, and that oligomeric procyanidins alleviate the loss of extensibility and viscosity after the dough is exposed to high temperatures. Collectively, these results imply that oligomeric procyanidins improve the rheological properties of flour-based foods, likely by (1) regulating sulfhydryl/disulfide redox reactions in the gluten network and impairing the formation of large polymers, and by (2) binding to hydrophobic sites in gluten proteins and altering their conformation.
Datum: 25.04.2018
Proteomic analysis of the impacts of powdery mildew on wheat grain
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Jie Li, Xinhao Liu, Xiwen Yang, Yongchun Li, Chenyang Wang, Dexian He
Powdery mildew of wheat is one of the major foliar diseases, causing significant yield loss and flour quality change. In this study, grain protein and starch response to powdery mildew infection were investigated. Total protein, glutenin and gliadin exhibited a greater increase in grains from infected wheat, while the content of total starch and amylopectin was decreased. Comparative proteomic analysis demonstrated that the overabundant protein synthesis-related proteins might facilitate the accumulation of storage proteins in grains from infected plants. The significant increase in triticin, serpin and HMW-GS in grains from infected wheat might relate to the superior gluten quality. In addition, overabundant carbohydrate metabolism-related proteins in grains from infected wheat were conducive to the depletion of starch, whereas the decreased abundance of ADP glucose pyrophosphorylase might be related to the deficiency of starch synthesis. These results provide a deeper understanding on the change of wheat quality under powdery mildew infection.
Datum: 25.04.2018
Systematic study on the extraction of antioxidants from pinhão (araucaria angustifolia (bertol.) Kuntze) coat
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Carlos Henrique Koslinski Santos, Michel Rocha Baqueta, Aline Coqueiro, Maria Inês Dias, Lillian Barros, Maria Filomena Barreiro, Isabel C.F.R. Ferreira, Odinei Hess Gonçalves, Evandro Bona, Marcos Vieira da Silva, Fernanda Vitoria Leimann
Food by-products containing bioactive substances have attracted attention due to the possibility of adding values to residues of the food industry. In this work, the extraction of phenolic compounds from pinhão seed coats (Araucaria angustifolia (Bertol.) Kuntze) using a central composite rotatable design was applied to obtain prediction models for the extract volume yield, total phenolic content, total phenolic acids and total flavonoids. Principal component analysis and hierarchical cluster analysis were implemented showing an evident poor effect of the temperature on phenolic compounds extraction, which is in accordance with the prediction model obtained by the experimental design for total phenolic acids. Volume yield presented a high positive correlation with extraction temperature, followed by solvent composition. Scanning electron microscopy showed that higher temperatures and lower ethanol percentages resulted in highly defibrillated pinhão coats that retained more extract after the extraction process, leading to lower volume yield percentages.
Datum: 25.04.2018
Application of response surface methodology to acidified water extraction of black soybeans for improving anthocyanin content, total phenols content and antioxidant activity
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Dayeon Ryu, Eunmi Koh
Acidified water extraction of total anthocyanin content, total phenol content and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity from black soybeans (Glycine max [L.] Merr. Cheongja4ho) was optimized using response surface methodology (RSM). A five-level, three-factor central composite design was employed to optimize the conditions for the maximum yields of these three components using19 different experiments. The HCl concentration (0.3–0.5%), solid-liquid ratio (1/30–1/50 g/mL) and extraction temperature (30–50 °C) significantly affected three components. The optimized conditions were HCl concentration of 0.359%, solid-liquid ratio of 1/54.2 g/mL and extraction temperature of 56.8 °C for total anthocyanin content (136.68 mg/100 g), total phenol content (1197.09 mg/100 g) and ABTS+ scavenging activity (211.65 mg/100 g). These experimental values fit well with the predicted values. Among three anthocyanins found in the black soybean extracts, cyanidin-3-O-glucoside was the major one (65–73% of the total), followed by petunidin-3-O-glucoside (17–23%) and delphinidin-3-O-glucoside (10–12%).
Datum: 25.04.2018
Optimization of lipase-catalyzed synthesis of β-sitostanol esters by response surface methodology
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Neumara L.S. Hakalin, María Molina-Gutiérrez, Alicia Prieto, María Jesús Martínez
The esters of β-sitostanol and fatty acids are known for their effect as cholesterol-lowering agents. In this work, the efficiency of three lipases as biocatalysts of the esterification of β-sitostanol and C16 and C18 fatty acids was compared. The sterol esterase of Ophiostoma piceae (OPEr) yielded the highest esterification rates and was selected for further optimization of the reaction. The effects of four parameters (temperature, enzymatic dosage, acyl donor concentration, and reaction time) on ester synthesis were investigated and the process conditions were optimized using response surface methodology (RSM). The best conditions for esterification for each fatty acid were predicted using a second-order model, and experimentally validated. Very high esterification efficiencies (86–97%) were observed using the predicted values for the four variables. This approach was shown to be suitable for optimizing the enzymatic production of β-sitostanol esters, which represents a green alternative to the chemical synthesis of these dietary complements.
Datum: 25.04.2018
Chemosensory characteristics of regional Vidal icewines from China and Canada
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Ling Huang, Yue Ma, Xin Tian, Ji-ming Li, Lan-xiao Li, Ke Tang, Yan Xu
This work aimed to compare the flavor characteristics of Vidal icewines from China and Canada and to establish relationships between sensory descriptors and chemical composition. Descriptive analysis was performed with a trained panel to obtain the sensory profiles. Thirty important aroma-active compounds were quantified by four different methodologies. Partial least squares discriminant analysis was used to identify candidate compounds, which were unique to certain sensory descriptors. The sensory profiles of icewines from China were characterized by nut and honey aromas, while icewines from Canada expressed caramel and rose aromas. Nut and honey aromas had a close correlation with 1-hexanol, isoamyl acetate, phenethyl acetate and phenylethyl alcohol. Caramel aroma was correlated with ethyl esters and lactones and rose aroma was correlated with terpenes.
Datum: 25.04.2018
Phenolic compounds as beneficial phytochemicals in pomegranate (Punica granatum L.) peel: A review
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Balwinder Singh, Jatinder Pal Singh, Amritpal Kaur, Narpinder Singh
Pomegranate peel (PoP), a juice byproduct often considered as a waste, comprises nearly around 30–40% portion of the fruit. Phenolic compounds (one class of bioactive phytochemicals) are primarily concentrated in the peel portion of pomegranate fruit. In PoP, the main phenolic compounds reported in the literature include flavonoids (anthocyanins such as pelargonidin, delphinidin, cyanidin along with their derivatives and anthoxanthins such as catechin, epicatechin and quercetin), tannins (ellagitannins and ellagic acid derivatives such as punicalagin, punicalin and pedunculagin) and phenolic acids (such as chlorogenic, caffeic, syringic, sinapic, p-coumaric, ferulic, ellagic, gallic and cinnamic acid). It is generally accepted that phenolic compounds can be more efficiently recovered from PoP by improving the extraction efficiency. The curative relevance of these compounds has been mainly assessed by in vitro experimentation. Therefore, conclusive clinical trials of the phenolic compounds present in PoP are essential for correct validation of their health benefits.
Datum: 25.04.2018
Deep insight into the minor fraction of virgin olive oil by using LC-MS and GC-MS multi-class methodologies
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Lucía Olmo-García, Juan J. Polari, Xueqi Li, Aadil Bajoub, Alberto Fernández-Gutiérrez, Selina C. Wang, Alegría Carrasco-Pancorbo
Several analytical methods are available to evaluate virgin olive oil (VOO) minor compounds; however, multi-class methodologies are yet rarely studied. Herewith, LC-MS and GC–MS platforms were used to develop two methods capable of simultaneously determine more than 40 compounds belonging to different VOO minor chemical classes within a single run. A non-selective and highly efficient liquid-liquid extraction protocol was optimized for VOO minor components isolation. The separation and detection conditions were adjusted for determining phenolic and triterpenic compounds, free fatty acids and tocopherols by LC-MS, plus sterols and hydrocarbons by GC–MS. Chromatographic analysis times were 31 and 50 min, respectively. A comparative assessment of both methods in terms of analytical performance, easiness, cost and adequacy to the analysis of each class was carried out. The emergence of this kind of multi-class analytical methodologies greatly increases throughput and reduces cost, while avoiding the complexity and redundancy of single-chemical class determinations.
Datum: 25.04.2018
Lipid oxidation and vitamin D3 degradation in simulated whole milk powder as influenced by processing and storage
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Fatemeh Mahmoodani, Conrad O. Perera, Grant Abernethy, Bruno Fedrizzi, Hong Chen
Vitamin D3 levels are known to sometimes decline in fortified products, which could be due to its degradation, although the exact mechanism is unknown. In this study, the influence of processing and storage conditions on lipid oxidation and vitamin D3 degradation were studied. Simulated whole milk powders with and without heat treatment were stored for 12 months at two different storage temperatures (20 °C and 40 °C). Stored samples without heat treatment showed higher lipid oxidation products analyzed by PV and TBARS values compared to those with heat treatment. Higher storage temperature also resulted in higher levels of lipid oxidation products. The concentration of vitamin D3 was also analyzed using UHPLC-MS/MS after PTAD derivatization in stored samples. An inverse relationship was observed between lipid oxidation products and vitamin D3 content. Finally, previtamin D3 and vitamin D3 oxidation products were quantified in stored samples using MRM analysis.
Datum: 25.04.2018
Zipper-like magnetic molecularly imprinted microspheres for on/off-switchable recognition and extraction of 17β-estradiol from food samples
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Wenting Zhu, Hailong Peng, Mei Luo, Ningxiang Yu, Hua Xiong, Ronghui Wang, Yanbin Li
Zipper-like on/off-switchable and magnetic molecularly imprinted microspheres (SM-MIMs) were constructed using acrylamide (AAm) and 2-acrylamide-2-methyl propanesulfonic acid (AMPS) as functional monomers for 17β-estradiol (17β-E2) recognition and extraction. The imprinted polymer interactions between poly(AAm) (PAAm) and poly(AMPS) (PAMPS) with on/off-switchable property to temperature, exhibited dissociation at relatively higher temperatures (such as 30 °C) and helped 17β-E2 enter into imprinted sites, leading to higher binding capability. Conversely, the interpolymer complexes between PAAm and PAMPS formed and blocked 17β-E2 access to imprinted sites at lower temperature (such as 20 °C). SM-MIMs were used as dispersive solid phase extraction (SPE) adsorbent with HPLC for 17β-E2 pretreatment and detection in food samples, and low limit detection (2.52 µg L−1) and quantification (10.76 µg L−1) with higher recovery were obtained. Therefore, SM-MIMs may be a promising adsorbent for 17β-E2 pretreatment in food samples owing to its advantages of on/off-switchable recognition, eco-friendly elution, and efficient separation.
Datum: 25.04.2018
Highly sensitive furazolidone monitoring in milk by a signal amplified lateral flow assay based on magnetite nanoparticles labeled dual-probe
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Lingzhi Yan, Leina Dou, Tong Bu, Qiong Huang, Rong Wang, Qingfeng Yang, Lunjie Huang, Jianlong Wang, Daohong Zhang
We presented a signal amplified lateral flow assay (LFA) based on magnetite nanoparticles (MNPs) labeled dual-probe and applied it in the high sensitive and rapid on-site detection of furazolidone metabolite of 3-amino-2-oxazolidinone (AOZ). The amplified signal benefited from high affinity between two probes of MNPs labeled murine monoclonal antibody (MNPs-MAb) and goat anti-mouse antibody (MNPs-GAMA) and was achieved by the generation of dual-probe network complex. This developed method could realize high sensitive detection of AOZ with a threshold value of 0.88 ng mL−1 and a detection limit of 0.044 ng mL−1, the sensitivity was at least 10-fold improved than that of the traditional gold nanoparticle based LFA. This facile developed assay was successfully applied for rapid detection of AOZ in milk samples. The proposed method paves a new way for on-site screening of other hazardous substances in food and can be referred in all lateral flow assays.
Datum: 25.04.2018
High humidity hot air impingement blanching (HHAIB) enhances drying rate and softens texture of apricot via cell wall pectin polysaccharides degradation and ultrastructure modification
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Li-Zhen Deng, A.S. Mujumdar, Xu-Hai Yang, Jun Wang, Qian Zhang, Zhi-An Zheng, Zhen-Jiang Gao, Hong-Wei Xiao
The effects of high humidity hot air impingement blanching (HHAIB) over a range of application times (30, 60, 90, and 120 s) on drying characteristics, hardness, cell wall pectin fractions contents and nanostructure, as well ultrastructure of apricot were investigated. Results showed that HHAIB reduced drying time and decreased the hardness of apricot by 20.7%–34.5% and 46.57%–71.89%, respectively. The water-soluble pectin (WSP) contents increased after blanching, while the contents of chelate-soluble pectin (CSP) and sodium-carbonate-soluble pectin (NSP) decreased significantly (P < 0.05). The hardness and drying time were found to correlate inversely with the WSP content, but positively with CSP and NSP contents. Atomic force microscopy (AFM) detection showed the decomposition and degradation of pectin fractions during blanching. Additionally, transmission electron microscopy (TEM) observation indicated that the cell wall structure was degraded and middle lamella integrity was destroyed by blanching.
Datum: 25.04.2018
Application of ultrasound to improve lees ageing processes in red wines
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Juan Manuel del Fresno, Iris Loira, Antonio Morata, Carmen González, Jose Antonio Suárez-Lepe, Rafael Cuerda
Ageing on lees (AOL) is a technique that increases volatile compounds, promotes colour stability, improves mouthfeel and reduces astringency in red wines. The main drawback is that it is a slow process. Several months are necessary to obtain perceptible effects in wines. Different authors have studied the application of new techniques to accelerate the AOL process. Ultrasound (US) has been used to improve different food industry processes; it could be interesting to accelerate the yeast autolysis during AOL. This work evaluates the use of the US technique together with AOL and oak chips for this purpose studying the effects of different oenological parameters of red wines. The results obtained indicate an increase of polysaccharides content when US is applied in wine AOL. In addition, total polyphenol index (TPI) and volatile acidity were not affected. However, this treatment increases the dissolved oxygen affecting the volatile compounds and total anthocyanins.
Datum: 25.04.2018
High throughput screening and profiling of high-value carotenoids from a wide diversity of bacteria in surface seawater
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Dalal Asker
Carotenoids are valuable natural colorants that exhibit numerous health promoting properties, and thus are widely used in food, feeds, pharmaceutical and nutraceuticals industries. In this study, we isolated and identified novel microbial sources that produced high-value carotenoids using high throughput screening (HTS). A total of 701 pigmented microbial strains library including marine bacteria and red yeast was constructed. Carotenoids profiling using HPLC-DAD-MS methods showed 88 marine bacterial strains with potential for the production of high-value carotenoids including astaxanthin (28 strains), zeaxanthin (21 strains), lutein (1 strains) and canthaxanthin (2 strains). A comprehensive 16S rRNA gene based phylogenetic analysis revealed that these strains can be classified into 30 species belonging to five bacterial classes (Flavobacteriia, α-Proteobacteria, γ-Proteobacteria, Actinobacteria and Bacilli). Importantly, we discovered novel producers of zeaxanthin and lutein, and a high diversity in both carotenoids and producing microbial strains, which are promising and highly selective biotechnological sources for high-value carotenoids.Graphical abstract
Datum: 25.04.2018
Cashew gum and maltrodextrin particles for green tea (Camellia sinensis var Assamica) extract encapsulation
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Francisca Silva, Lucicléia Torres, Larissa Silva, Raimundo Figueiredo, Deborah Garruti, Tamara Araújo, Antoniella Duarte, Débora Brito, Nágila Ricardo
Cashew gum and maltodextrin microcapsules containing green tea leaf extracts were made using a spray-dryer. Green tea extracts were submitted to cytotoxicity analysis and characterization of bioactive compounds. Three formulations of microcapsules were performed, which were then submitted to characterization through morphological study, particle diameter and distribution, zeta potential, Exploratory Differential Calorimetry, entrapment efficiency, dissolution test and X-ray diffraction. The extract had a high bioactive compound content and no cytotoxicity was observed. The amorphous microcapsules presented irregular shapes with a circular predominance and dentate surface, mean diameters varying from 2.50 to 3.64 μm, solubility ranging from 63% to 72.66%. Low values of microencapsulation efficiency, zeta potencial and dissolution profile were observed. The microparticles based on the dry extract of green tea present potential as a food ingredient and as a promoter of health benefits.
Datum: 25.04.2018
Calendar
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Datum: 25.04.2018
Alkali extraction of rice residue protein isolates: Effects of alkali treatment conditions on lysinoalanine formation and structural characterization of lysinoalanine-containing protein
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Zhaoli Zhang, Yang Wang, Chunhua Dai, Ronghai He, Haile Ma
The influence of alkali extraction conditions on the formation of lysinoalanine (LAL) and the structural characterization of lysinoalanine-containing protein in rice residue protein isolates (RRPI) were explored in this study. It was found that LAL content increased from 0.256 to 13.079 g/kg as NaOH concentration increased from 0.03 to 0.09 M and then decreased to 1.541 g/kg at 0.13 M NaOH. The extraction temperature and time were found to have a positive correlation with LAL content. The highest LAL content (25.679 g/kg) was observed with alkali extraction using 0.09 M NaOH at 75 °C for 120 min. The comparative structural analysis results showed that alkali treatment could degrade cystine, lysine, threonine and arginine to generate LAL; increasing alkali content would cause variations in secondary structure and micropore appearance on the surface of lysinoalanine-containing protein, whereas increasing alkali treatment temperature and time could enlarge the surface particle size of the protein.
Datum: 25.04.2018
Discrimination of organic milk by stable isotope ratio, vitamin E, and fatty acid profiling combined with multivariate analysis: A case study of monthly and seasonal variation in Korea for 2016–2017
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Ill-Min Chung, Jae-Kwang Kim, Kyoung-Jin Lee, Na-Young Son, Min-Jeong An, Ji-Hee Lee, Yeon-Ju An, Seung-Hyun Kim
This study examined the monthly and seasonal variations of δ13C, δ15N, fatty acids (FAs), and vitamin E in organic milk (OM) and conventional milk (CM) collected in Korea during 2016–2017, discriminating OM authenticity with chemometric approaches. Compared to CM, the mean δ13C and δ15N values were lower in OM, whereas the mean α-tocopherol and nutritionally desirable FA contents were higher in OM. Furthermore, δ13C, δ15N, and FA contents vary significantly with the season in OM, whereas α-tocopherol does not show a specific seasonal trend in either OM or CM. Chemometric approaches provided reliable chemical markers, notably C18:3n-3, C18:2n-6, and δ13Cbulk-milk, for accurate OM discrimination according to sampling season. Our findings elucidate milk nutritional quality issues and also provide valuable insight into the control of fraudulent OM labeling in Korea, with potential application in other countries.
Datum: 25.04.2018
Gypenosides as natural emulsifiers for oil-in-water nanoemulsions loaded with astaxanthin: Insights of formulation, stability and release properties
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Zhang Chen, Gaofeng Shu, Noamane Taarji, Colin J. Barrow, Mitsutoshi Nakajima, Nauman Khalid, Marcos A. Neves
The formulation, physicochemical stability and bioaccessibility of astaxanthin (AST) loaded oil-in-water nanoemulsions fabricated using gypenosides (GPs) as natural emulsifiers was investigated and compared with a synthetic emulsifier (Tween 20) that is commonly applied in food industry. GPs were capable of producing nanoemulsions with a small volume mean diameter (d4,3 = 125 ± 2 nm), which was similar to those prepared using Tween 20 (d4,3 = 145 ± 6 nm) under the same high-pressure homogenization conditions. GPs-stabilized nanoemulsions were stable against droplet growth over a range of pH (6–8) and thermal treatments (60–120 °C). Conversely, instability occurred under acidic (pH 3–5) and high ionic strength (25–100 mM CaCl2) conditions. In comparison with Tween 20, GPs were more effective at inhibiting AST from degradation during 30 days of storage at both 5 and 25 °C. However, GPs led to lower lipid digestion and AST bioaccessibility from nanoemulsions than did Tween 20.
Datum: 25.04.2018
Antityrosinase and antioxidant properties of mung bean seed proanthocyanidins: Novel insights into the inhibitory mechanism
Publication date:
15 September 2018Source:Food Chemistry, Volume 260
Author(s): Wei-Ming Chai, Chong Ou-Yang, Qian Huang, Mei-Zhen Lin, Ying-Xia Wang, Kai-Li Xu, Wen-Yang Huang, Dan-Dan Pang
This study investigated the structure, antioxidant activity, antityrosinase activity and mechanism of proanthocyanidins from mung bean seed [Vigna radiata (L.) Wilczek]. The structural composition were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), electrospray ionization-full-mass spectrometry (ESI-Full-MS), and high-pressure liquid chromatography-electrospray ionization-mass spectrometry (HPLC-ESI-MS) techniques. The mung bean seed proanthocyanidins were composed of procyanidins, prodelphinidins, and their rhamnosides. According to enzyme kinetic analysis, these compounds were potent, reversible, and mixed-type inhibitors of tyrosinase. They inhibited the enzyme activity by interacting with enzyme as well as substrates. The results of molecular docking showed that the interaction between mung bean seed proanthocyanidins and tyrosinase was driven by hydrogen bond, hydrophobic and electrostatic interactions. In addition, mung bean seed proanthocyanidins were demonstrated as powerful antioxidants. Therefore, this study confirmed a novel tyrosinase inhibitor and would lay a scientific foundation for their utilization in pharmaceutical and food industries.
Datum: 25.04.2018
The critical micelle concentration of lecithin in bulk oils and medium chain triacylglycerol is influenced by moisture content and total polar materials
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): JiSu Kim, Mi-Ja Kim, JaeHwan Lee
Effects of different moisture contents and oxidised compounds on the critical micelle concentration (CMC) of lecithin were determined in bulk oils and in medium-chain triacylglycerols (MCT). CMC of lecithin in MCT was significantly higher than that in other vegetable oils including olive, soybean, corn, and rapeseed oils (p < 0.05). Presence of moisture significantly affected the CMC of lecithin in MCT (p < 0.05). CMC of lecithin was high when the moisture content was below 900 ppm, whereas at a moisture content of 1000 ppm, CMC of lecithin decreased significantly (p < 0.05), and then started to increase. Addition of total polar materials (TPM), which are oxidation products, at 3 and 5% concentrations, decreased CMC of lecithin significantly (p < 0.05) in MCT, compared to when 0, 1, and 1.5% of TPM was added to MCT. As the degree of oxidation increased in corn oil, CMC of lecithin gradually decreased. Additionally, under different moisture contents, corn oils showed a similar pattern of CMC of lecithin in MCT, whereas oxidised corn oil had a little lower CMC of lecithin than unoxidised corn oil. The results clearly showed that the concentration of lecithin for the formation of micelles is greatly influenced by the presence of oxidation products and the moisture content in bulk oils.
Datum: 25.04.2018
Determination of a major allergen in fish samples by simple and effective label-free capillary electrophoretic analysis after background suppression in ion-exchange chromatography
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Linglin Fu, Jinru Zhou, Chong Wang, Yan Zhang, Aijin Ma, Yanbo Wang
A simple analytical method using ion-exchange chromatography (IEC) coupled with capillary zone electrophoresis (CZE) was newly developed for detection and quantification of parvalbumin (PV), a major allergen, in fish. The procedure of IEC for simple enrichment of PV crude extract was optimized. By using 25 mmol/L borate-borax buffer with 15 kV separation voltage at pH 9.2 for CZE separation, the migration time, separation efficiency and electrophoretic resolution greatly improved. Under the optimal conditions, PV was determined in 2.8 min, with the limit of detection (LOD) at 0.71 μg/mL (S/N = 3) and the recoveries at 89.6%–104.7%. We also found that only when the concentration of PV was above LOD reported here was the protein capable of stimulating human mast cell degranulation, indicating the biological significance of the LOD. Finally, the use of this method to analyze fish samples with simple sample preparation highlights the applicability for detection of allergens in seafood matrices.
Datum: 25.04.2018
Seasonal variation in Hibiscus sabdariffa (Roselle) calyx phytochemical profile, soluble solids and α-glucosidase inhibition
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Idolo Ifie, Beatrice E. Ifie, Dorcas O. Ibitoye, Lisa J. Marshall, Gary Williamson
Seasonal variations in crops can alter the profile and amount of constituent compounds and consequentially any biological activity. Differences in phytochemical profile, total phenolic content and inhibitory activity on α-glucosidase (maltase) of Hibiscus sabdariffa calyces grown in South Western Nigeria were determined over wet and dry seasons. The phenolic profile, organic acids and sugars were analysed using HPLC, while inhibition of rat intestinal maltase was measured enzymically. There was a significant increase (1.4-fold; p ≤ 0.05) in total anthocyanin content in the dry compared to wet planting seasons, and maltase inhibition from the dry season was slightly more potent (1.15-fold, p ≤ 0.05). Fructose (1.8-fold), glucose (1.8-fold) and malic acid (3.7-fold) were significantly higher (p ≤ 0.05) but citric acid was lower (62-fold, p ≤ 0.008) in the dry season. Environmental conditions provoke metabolic responses in Hibiscus sabdariffa affecting constituent phytochemicals and nutritional value.
Datum: 25.04.2018
The conversion and deglycosylation of isoflavones and anthocyanins in black soymilk process
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Yu-Hsuan Hsiao, Jung-Feng Hsieh
The conversion of isoflavones and anthocyanins during black soymilk processing including soaking and heating was investigated. During soaking procedure, the β-glucosidase activity, content of bioactive compounds including daidzein, genistein, delphinidin and cyanidin were significantly increased by deglycosylation reaction. After heating treatment at 90 °C for 1 h, the content of isoflavones β-glucosides including daidzin, glycitin and genistin were increased through a de-esterification reaction from malonyl-glucosides at high temperature. On the contrary, aglycone content including daidzein and genistein were no significant changed, this result indicated aglycones displayed well thermal stability. Moreover, anthocyanins including delphinidin-3-O-glucoside (D3G) and cyanidin-3-O-glucoside (C3G) were converted into delphinidin and cyanidin by glucose removal. HPLC analysis suggested that daidzein, genistein, D3G and C3G were bound with β-conglycinin and glycinin. Our results establish the conversion of bioactive components including daidzein, genistein, delphinidin and cyanidin by deglycosylation during soaking and heating progress and benefit to the production of soymilk.
Datum: 25.04.2018
The impact of high pressure processing on the phenolic profile, hydrophilic antioxidant and reducing capacity of purée obtained from commercial tomato varieties
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Maja Jeż, Wiesław Wiczkowski, Danuta Zielińska, Ireneusz Białobrzewski, Wioletta Błaszczak
The effect of high hydrostatic pressure (HHP) (450–550–650 MPa/5–10–15 min) on polyphenols profile of purée obtained from commercial tomato varieties (Maliniak, Cerise, Black Prince and Lima) was investigated. Individual polyphenols, total phenolic index (TPI) were quantified using a mass spectrometer (HPLC-MS/MS). Photochemiluminescence (PCLACW), cyclic voltammetry (CV) and ferric reducing antioxidant power (FRAP) assays were used to determine the antioxidant capacity of the hydrophilic extract. The results demonstrated that at certain processing conditions, HHP may enhance or decrease the nutritional quality of tomato purée. However, the tomato variety was a key factor influencing the polyphenols profile and the antioxidant capacity. A significant positive correlation was found among TPI, FRAP or CV parameters and the concentration of caffeic, ferulic, sinapic and p-coumaric acids, and epicatechin. On the other hand, significant positive correlation was observed among antioxidant capacity (PCLACW), TPC, rutin and naringenin concentration as well as chlorogenic and isochlorogenic acids.
Datum: 25.04.2018
Ferrofluid-based liquid-phase microextraction: Analysis of four phenolic compounds in milks and fruit juices
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Dezhi Yang, Guixiang Li, Lan Wu, Yaling Yang
A novel liquid-phase microextraction based on the ferrofluid was successfully applied for the extraction and determination of four phenolic compounds (bisphenol-A, bisphenol-AF, tetrabromobisphenol-A and 4-tert-octylphenol) in milks and fruit juices. In this study, a range of alkyl (C4–C10) alcohols as the carrier liquid were used for the preparation of ferrofluids. The study showed that an appropriate chain length of alkyl alcohol may improve the extraction efficiency and maintain the integrity of ferrofluids during extraction, so 1-heptanol (C7) was selected as the optimal carrier liquid. Specifically, the effects of various parameters on the extraction of phenolic compounds were investigated and optimized. Under the optimized conditions, the limits of detection were between 0.35 and 0.66 μg L−1. The intra-day and inter-day precision (RSD %) for the analytes at 10 and 50 μg L−1 were in the range of 3.2–6.7 % and 2.9–7.1%, respectively.
Datum: 25.04.2018
Rapid determination of cadmium in rice using an all-solid RGO-enhanced light addressable potentiometric sensor
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Wen Zhang, Yiwei Xu, Xiaobo Zou
Herein, an all-solid light addressable potentiometric sensor (LAPS) is presented for determination of cadmium (Cd) in rice. On the working surface of the LAPS, reduced graphene oxide (RGO) is introduced as a part of ion-to-electron transducer to improve ionophore behaviors. The composite modification of RGO and ionophore is validated with scanning electron microscopy. The as-fabricated sensor presents a rapid response in less than 10 s to target Cd. Meanwhile, it shows lower noise (0.23 mV) and better limit of detection (0.002 mg L−1) than LAPS (control) without RGO modification (0.37 mV; 0.008 mg L−1). With the proposed method, satisfactory precision, accuracy and selectivity are also established. This method is adopted in an extensive survey for 25 rice samples from 5 regions in China. The results are in very good agreement with those obtained using inductively-coupled plasma-mass spectrometry.
Datum: 25.04.2018
Quantification of ascorbyl adducts of epigallocatechin gallate and gallocatechin gallate in bottled tea beverages
Publication date:
30 September 2018Source:Food Chemistry, Volume 261
Author(s): Wei-Lun Hung, Siyu Wang, Shengmin Sang, Xiaochun Wan, Yu Wang, Chi-Tang Ho
Catechins are the major bioactive compounds existing in tea leaves (Camellia sinensis). Dehydroascorbic acid is (DHAA) a reactive dicarbonyl species and previous studies have demonstrated that catechins could effectively trap DHAA to form ascorbyl adducts of catechins, especially epigallocatechin gallate (EGCG). Since catechins in the aqueous solution are unstable due to their structural features, ascorbic acid (AA) is usually added to bottled tea beverages to protect catechins. However, whether ascorbyl adducts of catechins are formed in bottled tea beverages remains unclear. In this study, formation of ascorbyl adducts of EGCG increased along with increased incubation time when EGCG and AA were dissolved in the aqueous solution. Next, 6C-DHAA-EGCG and 8C-DHAA-EGCG were detected in both green tea and oolong tea beverages, and their concentrations ranged from 0.23 to 1.95 µM and 0.28 to 1.97 µM, respectively. Furthermore, an 8C-ascorbyl adduct derived from gallocatechin gallate was also found in some tea beverages.
Datum: 25.04.2018
Category: Current Chemistry Research
Last update: 28.03.2018.
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