This study aimed to investigate the effects of combined spatial electric field and subzero temperature storage on volatile flavor compounds and microbial community succession in marinated steak. Gas chromatography-mass spectrometry (GC-MS) and high-throughput sequencing of the 16S rRNA gene were performed to analyze the dynamic changes in volatile flavor compounds and the characteristics of the microbial community structure during refrigerated storage, subzero storage, and combined spatial electric field and subzero storage. Volatile flavor compounds with significant characteristics were identified based on odor activity value (OAV) calculations and multivariate statistical analysis, and their associations with the microbial communities were explored using Spearman correlation analysis. The results showed that a total of 39 volatile flavor compounds were detected during the low-temperature storage of marinated steak. Among these, hexanal, benzaldehyde, heptanal, octanal, phenylacetaldehyde, E-2-decenal, 2-methyl-3-heptanone, 2-nonanone, 1-octen-3-ol, dimethyl disulfide, nonanal, and limonene were identified as the main characteristic flavor compounds (OAV>1). Compared with the single refrigeration group, the synergy of space electric field treatment maintained the stability of the composition and relative content of alcohols, aldehydes, ketones, and esters and inhibited the accumulation of spoilage-related flavor compounds. In addition, the space electric field regulated the succession of microbial communities, slowing the rate of transition from psychrophilic bacteria to dominant spoilage bacteria. Correlation analysis indicated that the genera Pseudomonas and Acinetobacter played a key role in flavor changes and would be positively correlated with the production of spoilage markers, such as octanal, dimethyl disulfide, and nonanal. Therefore, space electric fields can inhibit the proliferation of spoilage bacteria in the short term, slow flavor deterioration, and extend the shelf life of prepared beef steaks, providing a highly promising new strategy for the preservation of meat products.

Fortification during germination is an effective strategy for improving the physicochemical properties of cereal starch. Therefore, this study investigated the synergistic effects of Zn fortification (0-200 mg/L) and ultrasonic treatment (200 W, 53 kHz, 15 min) on the functional properties and digestibility of germinated black rice (GBR) starch, with a focus on associated structural changes. The fortification treatment decreased starch and increased reducing sugar contents. It also lowered the amylose content, relative crystallinity, and FT-IR intensity ratio of starch. These structural changes altered starch functionality. The starch from GBR treated with 100 mg/L Zn combined with ultrasound (UGBR-Zn100) exhibited the highest swelling power and the lowest relative crystallinity. The solubility and swelling power of UGBR-Zn100 starch at 95°C increased to 15.90% and 22.39 g/g, while gelatinization enthalpy, peak viscosity, and trough viscosity decreased to 1.13 J/g, 2338.00 cP, and 1422.00 cP, respectively, with no significant change in the water absorption capacity. In vitro digestion results indicated that the fortification treatment increased the rapidly digestible starch content and digestibility. Meanwhile, zinc fortification and ultrasonic treatment showed an interaction effect on the increase in starch solubility and swelling power.

This study evaluated the volatile organic compounds (VOCs) and taste properties of Gorgon Euryale seeds processed by five methods (steaming, boiling, microwaving, roasting, and stir-frying) using electronic tongue (E-tongue), electronic nose (E-nose), gas chromatography-mass spectrometry (GC-MS), and gas chromatography-ion mobility spectrometry (GC-IMS). A total of 44 and 40 VOCs were identified by GC-MS and GC-IMS, respectively. Pyrazines (2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine) and furans (2-pentylfuran, 2-ethylfuran) played a major role in the baked aroma characteristics of roasted and stir-fried Gorgon Euryale seeds. Six and seven marker compounds were identified by Orthogonal Partial Least Square Discriminant Analysis (OPLS-DA) models for GC-MS and GC-IMS based on 12 VOCs with odor activity value > 1 and 18 VOCs with relative odor activity value > 0.1, respectively. OPLS-DA and principal component analysis score plots of the E-tongue and E-nose demonstrated that samples could be effectively distinguished in terms of flavor. This research provides a comprehensive basis for evaluating the impact of processing methods on the changes in flavor of Gorgon Euryale seeds. PRACTICAL APPLICATION: This work demonstrates that the use of E-tongue, E-nose, HS-SPME-GC-MS, and GC-IMS has the capability to thoroughly analyze the flavor profile of Gorgon Euryale seeds at both macro and micro levels. This approach effectively distinguishes Gorgon Euryale products subjected to different processing treatments and provides a reliable reference for evaluating and identifying the flavor quality of Gorgon Euryale seeds.

Fortified germination is regarded as a straightforward and potent approach to boost the nutritional value and bioactive compounds of cereal seeds, and it is also used for cereal micronutrient fortification. Zinc (Zn) and ultrasound treatments have been applied in the fortified germination of cereals. This paper primarily investigated the synergistic effects of Zn fortification at varying concentrations and ultrasonic treatment on germinated black rice and its associated metabolomic profile. The results indicated that Zn fortification coupled with ultrasonic treatment increased Zn content, total flavonoid content, total polyphenol content, and antioxidant properties of germinated black rice. Untargeted metabolomics analysis of germinated black rice without Zn fortification or ultrasound treatment (GBR), ultrasound-treated germinated black rice (UGBR), 150 mg/L Zn-treated germinated black rice (GBR-Zn150), and combined 150 mg/L Zn and ultrasound-treated germinated black rice (UGBR-Zn150) revealed 307 metabolites. The differential metabolites (DMs) analysis demonstrated that UGBR-Zn150 exhibited the most metabolic changes. A notable upregulation of DMs in the phenylpropanoids and polyketides (PPs) was observed. Among these metabolites, gossypetin, taxifoliol, datiscin, and irigenol exhibited a significant positive correlation with antioxidant ability (p < 0.05). The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed four significantly enriched metabolic pathways, which contributed to increased phenolic compounds and gamma-aminobutyric acid (GABA), thereby enhancing its nutritional value and antioxidant properties. These results suggest that Zn fortification combined with ultrasonic treatment may serve as a promising approach for improving the nutritional fortified profile of germinated seeds. PRACTICAL APPLICATION: The synergistic treatment of germination with Zn fortification and ultrasound is an effective approach to enhance the Zn content, nutritional quality, and functional properties of black rice. This method promotes the potential application of germinated black rice in functional foods and provides a novel strategy for addressing Zn deficiency issues.

This study evaluated the volatile compounds and taste properties of Gorgon Euryale seeds processed by five methods (steaming, boiling, microwaving, roasting, and stir-frying) using electronic tongue (E-tongue), electronic nose (E-nose), GC-MS, and GC-IMS. A total of 44 and 40 volatile compounds were identified by GC-MS and GC-IMS, respectively. Pyrazines (2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine) and furans (2-pentylfuran, 2-ethylfuran) significantly contributed to the baked aroma characteristics of roasted and stir-fried Gorgon Euryale seeds. Six and seven key aroma compounds were identified by OPLS-DA models for GC-MS and GC-IMS based on 12 volatile compounds with odor activity value (OAV) > 1 and 18 compounds with relative odor activity value (ROAV) > 0.1, respectively. OPLS-DA and PCA score plots of the E-tongue and E-nose demonstrated that samples could be effectively distinguished in terms of flavor. This study provides a comprehensive basis for evaluating the impact of processing methods on the flavor quality of Gorgon Euryale seeds.

This study investigated the effects of preheat treatment (70-100 degrees C) and syringic acid (SA) grafting on the antioxidant, antibacterial, and physicochemical properties of black soybean protein isolate (BSPI) before and after in vitro digestion. The results revealed that both preheat treatment and SA grafting increased the digestibility and the absolute zeta potential value of BSPI. However, as the preheating temperature increased, the antioxidant ability of BSPI decreased, which was improved by SA grafting. During in vitro digestion, the absolute zeta potential and antioxidant activities of preheated BSPI and preheated BSPI-SA complex followed the order: intestine > gastric > before digestion. Compared with before digestion, preheated BSPI with its SA complex after in vitro digestion exhibited excellent antibacterial activities. Importantly, the preheated BSPI-SA complex enhanced the SA recovery rate during digestion and SA stability, with the highest recovery rate observed for the SA-grafted BSPI with preheat treatment at 100 degrees C (BSPI100-SA). The principal component analysis sufficiently distinguished preheated BSPI and preheated BSPI-SA complexes. There were partitions between BSPI and BSPI-SA treated at different preheating temperatures. This study contributes to expanding the potential applications of BSPI with its SA complex in food products and offers guidance for designing SA delivery systems.

Cronobacter sakazakii in powdered infant formula (PIF) can infect infants with a mortality rate of up to 80%. In this study, a propidium monoazide–loop‐mediated isothermal amplification (PMA‐LAMP) assay was developed for fast and cost‐effective visual detection of viable C. sakazakii. The detection could be finished in 75 min and the results could be identified by the naked eye. The detection limits of the assay were as low as 1.2 × 101 cfu/mL and 1.2 × 102 cfu/mL for gel electrophoresis and naked eyes respectively. Finally, the assay also showed good reliability in the artificially contaminated PIF.

This study investigated preheated (25-100 degrees C) black soybean protein isolate (BSPI) conjugated with syringic acid (SA) (25 and 50 mu mol/g protein) under alkaline conditions, focusing on the structure, functional properties, and storage stability. The results revealed that the SA binding equivalent and binding rate on BSPI increased continuously as the preheat temperature increased. Additionally, preheating positively impacted the surface hydrophobicity (H0) of BSPI, with further enhancement observed upon SA binding. Preheating and SA binding altered the secondary and tertiary structure of BSPI, resulting in protein unfolding and increased molecular flexibility. The improvement in BSPI functional properties was closely associated with both preheating temperature and SA binding. Specifically, preheating decreased the solubility of BSPI but enhanced the emulsifying activity index (EAI) and foaming capacity (FC) of BSPI. Conversely, SA binding increased the solubility of BSPI with an accompanying increase in EAI, FC, foaming stability, and antioxidant activity. Notably, the BSPI100-SA50 exhibited the most significant improvement in functional properties, particularly in solubility, emulsifying, and foaming attributes. Moreover, the BSPI-SA conjugates demonstrated good stability of SA during storage, which positively correlated with the preheating temperature. This study proposes a novel BSPI-SA conjugate with enhanced essential functional properties, underscoring the potential of preheated BSPI-SA conjugates to improve SA storage stability.

The blood of domesticated animals possesses exceptional processing and functional characteristics.With advances in the slaughtering and processing industry, the comprehensive utilization of blood from domesticated animals has attracted wide attention. The processing and functional characteristics of the blood from domesticated animals were summarized, and the processing technologies for value-added products with functional components in the blood were introduced. Furthermore, the industrial application prospects of the blood were put forward, which would provide a reference for the value-added processing of such blood.

1,3-Dioleoyl-2-palmitoylglycerol (OPO) was synthesized by enzymatic interesterification using palm stearin rich in tripalmitin (PPP) and ethyl oleate. Enzymatic interesterification parameters such as temperature, water content, enzyme load, and substrate molar ratio were optimized. High contents of C52 (primarily OPO and its isomeric compounds) production (46.7%) and sn-2 palmitic acid (PA) content of 75.3% were detected. In addition, OPO-human milk fat substitute (HMFS) was blended with coconut, soybean, algal and microbial oils at a weight ratio of 0.70:0.18:0.11:0.004:0.007 to simulate fatty acids in human milk fat (HMF) according to the mathematical model. The main and important fatty acids in the Final-HMFS were within the ranges of those present in HMF. The Final-HMFS could promote the absorption of fats and minerals and the development of retina tissues in infants. The mixture of L-ascorbyl palmitate (L-AP) and vitamin E (VE) resulted in a synergistic antioxidant effect both in OPO-HMFS and OPO-HMFS emulsions. This finding has great significance in improving the quality and extending shelf-life of HMFS.

Here, we prepared novel composite gels composed of citrus insoluble nanofiber and amylose, and examined their potential to be used as fat replacers and inhibit lipid digestion. We further evaluated the effect of different nanofiber/amylose ratios on the texture, thermal stability, water distribution, microstructure and lipid digestion of the composite gels. The addition of nanofiber improved the hardness, gumminess, viscoelasticity, thermal stability, and water-holding capacity of the composite gels, as well as strengthen their interpenetrating three-dimensional network. The gel prepared at a nanofiber/amylose ratio of 1:4 could provide an oral sensory perception similar to that of cream and therefore can be used as a potential fat replacer. Moreover, the emulsion stabilized by nanofiber/amylose could well inhibit lipid digestion, and the nanofiber/amylose ratio of 1:4 could achieve the minimum release amount of free fatty acids (55.81%). These findings provide a reference for the development of potential fat replacers.

Black pork is a very popular pork consumer product in the market. Different from ordinary large white pigs, black pork has high nutritional value, rich in unsaturated fatty acids, high content of inosinic acid and protein, etc. It has the advantages of rich taste and unique flavor and is loved by consumers. Black pig breeds are abundant in China, the flavor of pig breeds in different regions is different. On the basis of summarizing the general procedure of flavor substances analysis of meat products, the volatile flavor substances and tasting substances of black pigs from Dingyuan, Hebei（Baoxu）, Laiwu, Yunnan, Beijing, Shanxi and Qinghai（Bamei） were analyzed and summarized, with reference to white pigs. The key flavor substances of black pork in different regions were determined. Based on the formation pathways of aroma and flavor producing substances of black pork, the main reasons leading to the flavor differences of black pigs in different regions were analyzed.The future research directions were put forward, so as to provide theoretical reference for people to selectively develop specific processed products of black pork and excavate the value of specific varieties of black pork in different regions.

Insoluble dietary fibre from citrus peels (CIDF) was found to have adsorption and inhibitory effect on the activity of pancreatic lipase (PL). CIDF-400 exhibited the greatest adsorption and activity inhibition effect on PL. The fluorescence quenching spectra indicated that CIDF could quench PL through a dynamic quenching process induced by the electrostatic interactions with only one binding site between them. The synchronous fluorescence and three-dimensional fluorescence spectra showed that CIDF might combine with PL to induce the increase in hydrophobicity and the reduction in polarity of tyrosine (Tyr) and tryptophan (Try) residues, which further led to the conformational alternations of PL. Moreover, circular dichroism (CD) showed that CIDF altered the secondary structure of PL, decreased α-helical structure content, and increased β-sheet structure content, potentially resulting in PL structure opening and its active site exposure. This study provides new perspectives for the application of CIDFs produced from agricultural waste in regulating lipid metabolism.

Biofortification using inorganic selenium has become an effective strategy to enhance selenium content in crops. In the present study, the effects of selenium biofortification on the chemical composition and antioxidant capacity of black soybean (BS) during germination were studied. The contents of selenium, total sugar, vitamin C, γ-aminobutyric acid, total polyphenols, and total flavonoids in selenium biofortified germinated black soybeans (GBS-Se) significantly increased compared to germinated black soybeans (GBS). However, the contents of soluble protein, fat, and reducing sugar were decreased, while fatty acid composition was not significantly different between GBS and BS. HPLC analysis showed that 12 phenolic acids of all samples, which mainly existed in free forms. Their contents increased at low concentration of selenium and decreased along with the rise of selenium concentrations. The antioxidant activity of GBS-Se as analyzed by Pearson correlation analysis positively correlated with the accumulation of phenolic substances. Principal component analysis (PCA) showed that GBS and GBS-Se were significantly different from BS. Moreover, the physicochemical indexes of GBS showed regularly changes with increasing selenium content, and those of GBS-Se50 and GBS-Se75 were significantly different from GBS. The results provide a systematic evaluation on the effect of selenium fortification on the germination of seeds and useful information for the development of Se-enriched functional foods. PRACTICAL APPLICATION: The organic selenium black soybean (BS) produced by the germination method can be directly processed and eaten to improve human health. In addition, complexes of organic selenium, vitamin C, and γ-aminobutyric acid of germinated BS can be developed into functional substances and applied to food or health products as functional ingredient and/or natural antioxidant supplements.

Houttuynia cordata Thunb (HCT) is a medicinal and edible herb that has beneficial effects on various diseases due to its diuretic, anti-inflammatory, anti-oxidative, anti-microbial, anti-viral, anti-cancer and anti-diabetic proper-ties. Most reports of its anti-cancer activity were conducted in vitro, and its effects on cutaneous squamous cell carcinoma (SCC) have not been investigated yet. Using DMBA/TPA induced SCC mice model, we found that topical treatment by HCT, as well as its bioactive ingredient monomer, efficiently inhibited tumor growth. Mechanistically, tumor infiltrating CD4+, Foxp3+ T regulatory cells (Tregs) were significantly reduced and CD8+/Treg cells ratio was largely increased in tumors after HCT treatment. In addition, several chemokines which function to recruit immune cells were largely reduced in SCC cancer cells treated by HCT in vitro. Our results demonstrate the therapeutic effects of HCT on cutaneous SCC and indicate it might inhibit cancer through regulating tumor infiltrating lymphocytes and the tumor immune microenvironments.

Developing efficient therapeutic strategies for combating bacterial infection remains a challenge owing to the indiscriminate utilization of antibiotics and the prevalence of multidrug-resistant (MDR) bacteria. Herein, highly graphitic-N-doped graphene quantum dots (N-GQDs) with efficient NIR-II photothermal conversion properties were synthesized for the first time for photothermal antibacterial therapy. The obtained N-GQDs exhibited strong NIR absorption ranging from 700 to 1200 nm, achieving high photothermal conversion efficiency of 77.8% and 50.4% at 808 and 1064 nm, respectively. Outstanding antibacterial and antibiofilm activities against MDR bacteria (methicillin-resistant Staphylococcus aureus, MRSA) were achieved by the N-GQDs in the presence of an 808 or 1064 nm laser. In vivo investigations verified that the generation of hyperthermia by N-GQDs plus a NIR-II laser can combat MDR bacterial infections and thus significantly accelerate wound healing. Our work provides a novel carbon-based nanomaterial as a photothermal antibacterial agent for efficiently avoiding bacterial resistance and fighting MDR bacterial infections.

Background and Objective: Biofortification with inorganic selenium has become a key strategy to enhance selenium content in crops. This study aimed to investigate the changes of phenolic compounds and their effects on antimicrobial and antioxidant activities during in vitro digestion of selenium biofortified germinated black soybeans (GBS-Se). Findings: The bioaccessibility of total polyphenols and total flavonoids in GBS-Se were significantly lower than those of germinated black soybeans (GBS). p-Coumaric acid and salicylic acid in GBS-Se and GBS increased significantly in the oral phase; syringic acid and benzoic acid were the main phenolic acids in the gastric phase, while phenolic acids decreased continuously in the intestinal phase. There was some minor difference between the antioxidant activities of GBS-Se and GBS in vitro digested products, but their 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging and ferric reducing antioxidant power reducing capacities increased compared with those before digestion. In addition, inhibitory effects on Escherichia coli and Staphylococcus aureus were observed only in undigested black soybean phenolic extracts. Conclusions: Selenium fortification affected the phenolic compounds and their bioaccessibility of GBS, which should be considered in nutrition research. Significance and Novelty: These results could help systematically evaluate the effect of selenium fortification on the digestibility of phenolic compounds in GBS and provide a reference for the development and application of Se-enriched functional foods.

Nine steaming nine sun-drying is a traditional processing technology for food or medicinal materials. The dynamic changes of the proximate composition, protein structure and volatile compounds during nine-time steaming and sun-drying of black soybeans (BS) were studied. The proximate composition results showed that the content of protein, carbohydrate and fat of BS decreased after processing, whereas the relative content of amino acids remained basically unchanged. Protein structure was evaluated using Fourier transform infrared spectroscopy (FT-IR), Ultraviolet absorption spectroscopy (UV) and Fluorescence spectroscopy. FT-IR result revealed that the relative contents of β-sheet and β-turn of the secondary structure of black soybean protein isolate (BSPI) decreased but the relative contents of α-helix and random coil increased after steaming and sun-drying. The results of UV and fluorescence spectroscopy confirmed changes in the protein conformation. In addition, SPME-GCMS analysis demonstrated that hydrocarbons, alcohols and aldehydes were the main volatile compounds. The relative contents of 1-octen-3-ol and hexanal, which are the main sources of beany flavor decreased significantly compared with raw BS. Principal component analysis (PCA) results showed that the volatile compounds of nine steamed and nine sun-dried BS could be well distinguished during the process. These findings may therefore provide a scientific basis for the application of nine-time steamed and sun-dried BS in food industry and contribute to the understanding of process-induced chemical transformations in this ancient processing technique.

The effectiveness of two lipophilic derivatives of the natural phenol, gallic acid (GA), synthesized using methyl gallate as starting material was investigated. The antioxidant activities of these novel phenolics compared to GA, tert-butylhydroquinone (TBHQ) and butylated hydroxytoluene (BHT) were evaluated in bulk oil, emulsion and the DPPH systems. The results showed that the new compounds effectively delayed lipid oxidation much better than GA and other antioxidants under Rancimat (100-140 °C) and emulsion tests. In the bulk oil system at 65 °C, they still behaved better than GA, but TBHQ had the highest activity. Thus, replacing the electron-withdrawing carboxylic group on GA by covalently linking sterically hindered phenols to its phenyl ring increased its lipophilicity and also resulted in synergistic effects which improved overall antioxidant activity through stabilization of the phenoxy radical. These new antioxidant variants satisfy industrial demands for bioactive ingredients with strong antioxidant potentials under different food processing conditions.