Journal of the Science of Food and Agriculture最新文献

Background: The powderization of salted egg yolks can circumvent the gelatinization issues that occur during frozen storage. In this study, salted egg yolk powder (SEYP) was prepared using microwave-assisted foam drying (MFD) technology.

Results: The results show that, compared to traditional microwave drying and hot-air drying, the SEYP prepared by MFD exhibits a bright color and a loose structure, and shows significant improvements in emulsifying properties, lecithin retention rate and antioxidant activity (P < 0.05). The optimal microwave power for MFD of SEYP, established through principal component analysis, is 350 W, with no requirement for a cooking treatment of the salted egg yolks. Gas chromatography-mass spectrometry identified n-butanol, hexanal, nonanal, ethyl acetate, d-limonene and isopentanal as the primary volatile compounds in SEYP, contributing to its unique flavor profile. Furthermore, the SEYP prepared using MFD at 350 W also shows a reduction of 18.88% in the content of bitter-tasting amino acids compared with microwave drying.

Conclusion: In summary, MFD technology is a green and efficient drying method suitable for the preparation of flavor-type SEYP. © 2024 Society of Chemical Industry.

Background: It is imperative to enhance the quality of sprouts since they are a rich source of various primary and secondary metabolites. The objective of this work was to examine how multiwalled carbon nanotubes (MWCNTs) priming at various concentrations affected the nutritional qualities of four horticultural plants (T. foenum-graecum, L. grandiflorum, L. sativum and A. graveolens) and their sprouting processes.

Results: Among the four applied concentrations (10-60 mgL^-1), MWCNTs at 10 and 40 mg L⁻¹ induced the highest biomass accumulation in L. grandiflorum and T. foenum-graecum, respectively, while 60 mg L⁻¹ was most effective for L. sativum and A. graveolent. MWCNTs induced growth by enhancing photosynthesis, as shown by increased chlorophyll content and rubisco activity, which rose by 27%, 17%, 23% and 12% in T. foenum-graecum, L. grandiflorum, L. sativum, and A. graveolens, respectively. Enhanced photosynthesis by MWCNTs improved sugar metabolism as indicated by increased activity of sugar metabolic enzymes such as amylase, starch synthase and invertase. This also supplied the carbon necessary for the production of primary (amino acids, fatty acids and organic acids) and secondary (flavonoids and polyphenols) metabolites. There was consistently higher activity of antioxidant enzymes (catalase and peroxidase). Interestingly, species-specific reactions to MWCNT priming were observed, where L. sativum sprouts showed the highest antioxidant activity, followed by A. graveolens.

Conclusion: MWCNT priming improves sprout growth and nutritional quality by boosting metabolic processes and antioxidant activity, presenting a promising approach for sustainable agriculture. © 2024 Society of Chemical Industry.

Background: Transglutaminase (TGase) is a heat-resistant biocatalyst with strong catalytic activity, which functions effectively under moderate temperature and pH conditions, and is used widely in protein cross-linking and recombination. Transglutaminase cross-linking is a novel and specific modification method for black bean protein isolate (BBPI). This article investigates the effect of transglutaminase cross-linking on the structure and emulsification performance of heated BBPI.

Results: Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed that heated BBPI with TGase had a higher molecular weight than heated BBPI without TGase, and the protein bands widened with increasing enzyme activity, indicating that TGase cross-linking promoted protein molecule aggregation. A high molecular weight polymer can better stabilize the oil-water interface, preventing the emulsion from layering. Fourier transform infrared (FTIR) spectroscopy showed that the α-helix content decreased from 15.64% to 13.75%, and the β-sheet content increased from 48.13% to 54.08%. The decrease in α-helix content and increase in β-sheet content could make the structure more stable and improve the emulsifying properties of heated BBPI. When TGase was 20 U g^-1, the protein emulsification activity index (EAI) reached its highest value of 1.87 m² g^-1, and the emulsification stability index (ESI) value was 0.27 min (P < 0.05); these figures were 0.19 m² g^-1, and 0.07 min higher, respectively, than in the sample without added TGase.

Conclusion: In summary, transglutaminase cross-linking has a positive effect on the structure and emulsification performance of heated BBPI and can be used as an effective method for BBPI modification. © 2024 Society of Chemical Industry.

Background: Radix Bupleuri has been widely used for its plentiful pharmacological effects. But it is hard to evaluate their safety and efficacy because the concentrations of components are tightly affected by the surrounding environment. Thus, Radix Bupleuri samples from different regions and varieties were collected. Based on the experimental and computational Raman spectrum, machine learning is emphasized for certain obscured characteristics; for example, linear discriminant analysis (LDA), support vector machine (SVM), eXtreme gradient boosting (XGBoost) and light gradient boosting machine (LightGBM).

Results: After dimension reduction by LDA, models of SVM, XGBoost and LightGBM were trained for classification and regression prediction of Bupleurum production regions. Support vector classifiers achieved the best accuracy of 98% and an F1 score above 0.96 on the test set. Support vector regression has a good fitting performance with an R² score above 0.90 and a relatively low mean square error. However, complex models were prone to overfitting, resulting in poor generalization ability.

Conclusion: Among these machine learning models, the typical LDA-SVM models, consistent with the high-performance liquid chromatography results, demonstrate great performance and stability. We envision that this rapid classification and regression technique can be extended to predictions for other herbs. © 2024 Society of Chemical Industry.

Background: Electron beam irradiation treatment is a novel technology that uses low-dose ionizing radiation for the treatment of crops or food to enhance their quality. This study investigated the effects of electron beam irradiation on the microstructure, physicochemical properties, and bioactive compounds of areca nuts.

Results: As the irradiation dose increased, the cellulose, hemicellulose, and lignin content in the areca nuts decreased significantly, whereas the polysaccharide and pectin content increased gradually. The hardness, chewiness, and adhesiveness of areca nuts reached their lowest values when the irradiation dose was within the range of 6-9 kGy, indicating that irradiation effectively reduced the hardness of the areca nut fibers. The decrease in crystallinity led to the formation of loose structures in the fibers upon irradiation, thereby improving their water retention, expansion, and oil-holding capacity, which are beneficial for the subsequent processing of areca nut-based chewable products. The water- and oil-holding capacities of the areca nuts peaked when the irradiation dose was within the 6-9 kGy range. Electron irradiation also affected the content of active substances in the areca nuts, particularly alkaloids, flavonoids, and polyphenols, showing an overall trend of initial increase followed by subsequent decrease.

Conclusion: Electron irradiation was not only effective in softening the fibers but it also impacted the overall quality of the areca nuts significantly. The results provide valuable reference data for improving the quality of areca nuts through electron beam irradiation technology. © 2024 Society of Chemical Industry.

Background: Whole grain food has gradually come into view because of its high nutritional value, but the incidence of wheat allergies has been increasing year by year. Ozone is a new non-thermal desensitization technology in food processing, and its effect on coarse wheat bran protein has received little study. We investigated the effects of different ozone airflow rates and treatment times on wheat bran allergenic property and protein structure.

Results: The ozone treatment time of 30 min at an airflow rate of 5 L min^-1 reduced the coarse wheat bran allergenic property by 61.14%; subunits of 33, 46, 48 and 68 kDa were significantly less allergenic via western blotting; and the lowest releasing rate of β-hexosaminidase was 25.32% in the cell model of rat basophilic leukaemia 2H3. According to secondary structure and chemical interaction determination, the protein molecules were reorganized and aggregated by disulfide bonds and hydrophobic contacts following ozone exposure.

Conclusion: Ozone treatment has a beneficial potential in reducing the allergenic property of coarse wheat bran and improving the safety of whole wheat products. © 2024 Society of Chemical Industry.

Background: This study used single-factor experiments and response surface methodology to optimize ultrasound time (10-50 min), particle size (0-80 mesh) and extraction time (60-180 min) for the ultrasound-assisted extraction of rosemary essential oil (REO). The resulting REO (0-2.5%, w/w) was then incorporated into citrus pectin (CP) to prepare CP/REO composite films before determining their microstructure, mechanical, barrier and antioxidant properties, alongside their ability to improve the shelf life of chilled beef.

Results: A sonication time of 41 min, a crushing degree of 40 mesh and an extraction time of 135 min were optimum for extracting 1.91% of REO, with the essential oil also showing good antioxidant activity. Characterization of the composite film further revealed that CP had an excellent film-forming ability and that REO was uniformly distributed in the pectin matrix through hydrogen bonding. The film displayed optimum mechanical and barrier properties at an REO concentration of 1.5% which also significantly enhanced antioxidant activity. Furthermore, the CP/1.5 REO film reduced the total viable count, delayed oxidative rancidity and maintained good color during beef storage, thereby extending the latter's shelf life by 6 days.

Conclusion: The novel food packaging film could successfully maintain the quality of chilled meat. © 2024 Society of Chemical Industry.

Background: Brassica juncea L. (family Brassicaceae) or Indian mustard is a fast-growing oilseed crop. Climate changes mean that it is very important to evaluate the effects of salinity stress on B. juncea. The aim of this study was therefore to show the metabolic effect of salinity stress on shoots and roots using two cultivation models - hydroponic and microplot - in different cultivars, including RH-725 and RH-761. Salinity levels of 5, 7.5, and 10 dS m⁻¹ were investigated, and compared with a control of 0 dS m⁻¹, using untargeted metabolomics with gas chromatography-mass spectrometry (GC-MS) post-silylation, focusing on metabolic markers such as proline and glycine-betaine.

Results: A total of 56 metabolites were identified, with the most prevalent classes belonging to sugars (8), followed by organic acids (13), amino acids (11), and fatty acids/esters (11). Shoots were found to have a higher sugar content than roots. Increases in unsaturated fatty acids were also associated with salinity stress, compared with a decrease in saturated fatty acids. Absolute levels of proline and glycine-betaine correlated with salinity stress, with the largest increases detected in shoots grown under hydroponic conditions, particularly for the RH-761 cultivar. Multivariate data analyses revealed that roots were more affected than shoots, regardless of cultivation model.

Conclusion: These findings might explain the different metabolic behavior of B. juncea's roots and shoots under various levels of salinity, associated with higher levels of free sugars in shoots and lipids in roots. © 2024 Society of Chemical Industry.

Background: Sesame paste faces issues with poor colloidal stability during storage, thereby affecting product quality and consumer experience. This study aimed to modify the proteins in sesame paste through stone milling and investigated the differences in stability produced in this environment, with the goal of addressing this issue.

Results: As the number of grinding times increased from one to three, the median diameter of sesame paste significantly decreased from 85 to 74 μm (P < 0.05), and the centrifugal oil separation rate dropped from 9.05% to 6.82%. Rheological measurements indicated an increase in the flow behavior index (n) from 0.51 to 0.61. Confocal laser scanning microscopy results revealed a more uniform co-distribution of protein and oil when ground thrice. The β-sheet content of the protein in sesame paste increased from 52.92% to 56.34%, with enhancements in surface hydrophobicity, hydrophobic interactions and emulsification of protein. When the number of grinding times increased to five, the particle size of the sesame paste was further reduced and the β-sheet content of the protein decreased to 51.00%, while the oil separation rate increased to 7.78%.

Conclusion: Stone milling induces structural modifications in proteins, which in turn alter the internal structure of sesame paste, resulting in varying levels of oil separation at different grinding times. Among them, sesame paste ground thrice showed a 25% reduction in the oil separation rate and experienced minimal oil separation over 120 days, making it suitable for practical production. © 2024 Society of Chemical Industry.

Background: Amylose has a major influence over starch properties and end-use quality in wheat. The granule-bound starch synthase I, encoded by Wx-1, is the single enzyme responsible for amylose synthesis. Natural null mutants of Wx-1 appear at extremely low frequencies, particularly in the Wx-D1 locus, where only four spontaneous null variants have been identified, with different geographic origins. The current study identified an induced Wx-D1 null mutant (M4-9484) from the M₄ generation of an ethyl methanesulfonate-mutagenized population of wheat cv. 'SM126'.

Results: The sequencing showed that the complete Wx-D1 ORF sequences of 'SM126' and M4-9484 were 2862 bp long and that there was one SNP mutation between them. The mutation was located at the RNA splice site within the junction of exon 8 and intron 8, which led to abnormal transcription of Wx-D1, with five different aberrant transcripts being identified in the mutant. The Wx-D1 null allele resulted in amylose and total starch content being decreased in M4-9484 in comparison with the wild-type 'SM126', with higher swelling capacity and being fully pasted at higher temperatures than the wild-type parent.

Conclusion: The mutation of the Wx-D1 null gene affects the formation of amylose directly, resulting in significantly altered starch properties. This discovery offers valuable insights for enhancing wheat starch quality and contributes to the diversification of starch characteristics. It also deepens our understanding of the genetic and molecular mechanisms underlying amylose synthesis, thereby supporting breeding programs. © 2024 Society of Chemical Industry.