Food Chemistry: X最新文献

We here analyzed changes in the proportion and content of chiral isomers of linalool and its derivatives in "Hainan dayezhong" throughout its life cycle from tea tree growth and tea manufacturing to brewing. The chiral isomers of aromatic compounds present in fresh tea leaves were found to undergo substantial diurnal and seasonal changes during tea tree growth, and their proportions varied slightly across different leaf positions. The chiral isomer content of linalool and its derivatives was consistently higher in stems than in leaves. Pest and disease stress significantly increased the proportion and content of type-R aroma. The proportion of chiral isomers underwent no considerable change during black tea manufacturing. However, their content varied dramatically among different processes. Diversity in the proportion and content of chiral isomers was observed in the wild tea tree. Further research should focus on breeding "Hainan dayezhong" wild resources to generate clones with high aroma quality.

Oxidative stress and microbial growth deteriorate food quality and cause safety risks. Therefore, the present study was investigated to explore the nutritional, sensorial, anti-oxidative and anti-microbial attributes of flaxseed powder (FP) supplemented at 2-8 % (i.e., T₁-T₄) level in mutton patties. Among extracts, the aqueous flaxseed extracts exhibited the highest total phenolic contents (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) activities i.e., 275 mg GAE/g, 75 % and 57 mg/g, respectively. The results exhibited significant increase (p < 0.05) in protein, and ash contents from 10.7 to 20.6 and 1.3-2.4 (g/100 g) on addition of FP at 2-8 % in mutton patties, respectively. Likewise, the mutton patties exhibited significant (p < 0.05) decrease in pH and thiobarbituric acid reactive substances (TBARS) of T₁-T₄ from 7.1 to 3.4 and 317-46 than control i.e., 6.64-4.12 and 453.75-563 at 0-16 days. Among color of mutton patties, L ^⁎ values decreased from 37 to 25, while, b ^⁎ values increased from 10 to 13 on addition of 2-8 % FP in mutton patties at 0-16 days for T₁-T₄, respectively. A significant decrease (p < 0.05) in total plate counts (TPC), Salmonella and E. coli of mutton patties was recorded in T₀-T₄ from 4.2 to 2.8, 0.8-0.3, and 2.1-0.3, respectively at 16th day of storage, respectively. Sensory experts rated the T₁ (i.e., 2 % FP supplemented mutton patties) owing to their best sensory scores and overall acceptability. Conclusively, owing to better potential of FP in improving the nutritional and microbial quality of mutton patties, the study further suggests its ability to act as a novel functional ingredient of choice in shelf-life extension of other food products.

The increase in lactose intolerance, the rise of veganism, the pursuit of healthy lifestyles, environmental awareness and concern for animal welfare have led to an increase in consumer demand for plant-based yogurts. The high nutritional value of nuts makes them an ideal ingredient for the production of plant-based yogurts. The main challenge for such products is to achieve a similar taste to traditional yogurt while improving shelf life. In recent years, extensive research has been conducted on this topic. The nutritional and health properties of yogurts made from different types of nuts, traditional and innovative processing technologies, and the effects of fermentation on the nutritional value, sensory characteristics, and texture of the yogurts are described. This review provides a comprehensive overview of the nutritional and manufacturing process of nut yogurts and offers possible directions for development and innovation of health food products.

This study reports a comparative evaluation of the physicochemical and functional properties of fava bean albumin, globulin and glutelin proteins. The fava bean globulins had significantly (p < 0.05) higher protein content (88.49 %) than the albumin (83.47 %) and glutelin (86.71 %). Far-UV circular dichroism results indicate low contents of α-helix, but high levels of unordered and β-sheet structures in the albumin and globulin. Higher surface hydrophobicity of the globulins was directly related to formation of oil-in-water emulsions with smaller oil droplet sizes, and better foaming capacity than the albumin and glutelin. The albumin had a broad range (32-92 %) of protein solubility that covers acidic and alkaline pH while glutelin exhibited significantly higher in vitro protein digestibility (77.33 %) when compared to the 75.34 and 71.73 % for globulin and albumin, respectively. We conclude that each fava bean protein fraction may find specific uses as ingredients for the formulation of various food products.

Egg yolk phospholipids are commercially valuable products that are beneficial to human health. Previous research on phospholipids in egg yolk mainly focuses on phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), and fatty acid compositions, and neglects the esterification position and other bioactive phospholipids. This study found a total of 19 classes of phospholipids and 275 subclasses using lipidomics. The study firstly found that egg yolks were also rich in glucosylceramides, galactosylceramides, lactosylceramides, gangliosides, and plasmalogens with polyunsaturated fatty acids (PUFAs) at the high bioavailable sn-2 position. Docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), α-Linolenic acid (ALA), and arachidonic acid (ARA) were esterified at sn-1 position of PC and sn-2 position of PE, phosphatidyl inositol (PI) and phosphatidic acid (PA). Microalgae feeding contributed to the deposition of PUFAs at sn-2 position and increased the contents of plasmalogens. The results provided detail the phospholipid profiles of egg yolk to improve understanding of its nutrition.

Protein concentrate (PC) is a potential solution to address the global protein shortage, with Indonesian shortfin eel being a suitable raw material. This research investigates the impact of ultrasound pretreatment and extraction parameters on the nutritional quality of eel protein concentrate (EPC). The study involved ultrasonic pretreatment at different times and power, and solvent extraction with different solvents, temperature, and solvent-solid-feed-ratio (SSFR). The results showed that the recommended conditions for EPC preparation were a mixture of ethanol-hexane, ultrasonic pretreatment at 250 W for 25 min, extraction temperature and SSFR of 40 °C and 6:1 v/w. The protein content of EPC increased gradually with the increase of SSFR until it reached a ratio of 6:1, further increase in SSFR promoted the development of a pseudo-homogeneous system, leading to a reduction in the solvent-eel flesh contact and the relative velocity between the extracting solvent and eel flesh, and consequently decreased the extraction yield. The prepared EPC is classified as type B EPC, with a protein content of 89.62 %w.b. and a lipid content of 2.21 %w.b. The EPC contains five types of peptides with a molecular weight of 5.00-76.00 kDa, with the main fraction having a MW ranging from 10.00 to 15.00 kDa, indicating potential for functional food products.

Aiming to enable online freshness-monitoring of meat within modified-atmosphere package, we developed a ratiometric array that was fluorescently responsive to volatile organic compounds-ammonia (NH₃) released by protein decaying. The array was consisted of two 3 mm × 6 mm rectangles precisely and uniformly printed with fluorescein isothiocyanate (FITC) as indicator and rhodamine B (RhB) as internal reference on the filter-paper, respectively. The fluorescence intensity of the array area was calibrated according to Green/Red ratio of the digitalized pixels extracted from images facilitated by a smartphone. The fluorescence-ratiometric sensor array displayed remarkable detection performances, including high sensitivity (LOD = 1.1 ppm), stability (91 % responding attenuation over 10 d of storage) and reproducibility (RSD < 10 %), which was further validated with real pork and shrimp samples. Subsequently, the fluorescent signals of the dual-rectangle array showed high correlation to the total volatile base nitrogen value that was officially used for indexing the meat freshness status.

Strawberries are valued for their aroma, which is mainly determined by volatile organic compounds (VOCs). Wild strawberries, with broader and more intense VOC profiles, are especially important in breeding programs. Using HS-SPME-GC-MS, 126 VOCs were identified in the ripe fruit of 22 cultivars from four wild strawberry species. Significant interspecies differences were found, with Fragaria mandshurica and F. nilgerrensis showing several times higher VOC levels than F. vesca and F. viridis, primarily due to high lactone content (up to 79.71 % of total VOCs). Phylogenetic analysis revealed conserved VOC profiles within species and genotype-aroma correlations. PCA and PLS-DA identified 60 biomarkers explaining 37.07 % of the variance, with 10 biomarkers validated for species identification, achieving 100 % accuracy. Key biomarkers for F. mandshurica included furaneol and perillyl acetate, while butanoic acid butyl ester was characteristic of F. vesca. This study emphasizes the role of VOCs as biomarkers for species differentiation and their potential in strawberry breeding.

This study investigates the optimization of bioactive components in thermosonicated black carrot juice using response surface methodology (RSM) and gradient boosting (GB) modeling techniques. Thermosonication, a combination of ultrasound and heat, was applied to enhance the nutritional quality of black carrot juice, which is rich in anthocyanins, phenolic compounds, and antioxidants. The study examined the effects of temperature, processing time, and ultrasonic amplitude on total carotenoid content (TCC), total anthocyanin content (TAC), ferric reducing antioxidant power (FRAP), and total phenolic content. RSM demonstrated higher prediction accuracy compared to GB, identifying optimal processing conditions at 48.68 °C, 11.15 minutes, and 82.62% amplitude. Thermosonication significantly increased total phenolic content to 414.28 mg GAE/L, surpassing traditional pasteurization. Sensory analysis, conducted via fuzzy logic, indicated improved sensory properties, including aroma, taste, and color, in thermosonicated samples. This study undercomes thermosonication as a promising method for improving both bioactive compounds and sensory quality in black carrot juice.

Chemical compounds: Chlorogenıc acid (PubChem CD:1794427); caffeic acid (PubChem CD: 689043); vanillin (PubChem CD: 1183); rutin (PubChem CD: 5280805); naringin (PubChem CD: 442428); rosmarinic acid (PubChem CD: 5281792); t-ferulic acid (PubChem CD: 445858); o- coumaric acid (PubChem CD: 637540); (PubChem CD: quercetin 5280459); 4-hyroxybenzoic acid (PubChem CD: 135).

An ultrasensitive and selective voltammetric platform combined a molecularly imprinted poly(pyrrole) membrane with Ag-nanoparticle-functionalized black phosphorus nanosheets (MIP/BPNS-AgNPs) was developed for trace GAT detection. The physicochemical properties of the MIP/BPNS-AgNPs were studied by various spectroscopic and electrochemical techniques. BPNS-AgNPs improved the ambient stability and electrochemical activity of the BPNS and possessed a large surface area for accommodating abundant templates to produce specific imprinted sites. The resulting MIP/BPNS-AgNP-modified glassy carbon electrode (GCE) greatly enhanced voltammetric responses for GAT. The MIP/BPNS-AgNP/GCE exhibited admirable GAT determination performance, with two linear responses (0.001-1 and 1-50 μM), high sensitivity (9.965 and 0.5378 μA μM^-1), and a low detection limit of 0.2 nM. In addition, the MIP electrode could selectively detect GAT in complex matrices and retain roust responses for a month. The applicability of MIP/BPNS-AgNP/GCE toward the detection of GAT in pharmaceutical formulations, milk, and human serum was verified with satisfactory results.