The potential meat flavoring derived from Maillard reaction products of rice protein isolate hydrolysate-xylose via the regulation of temperature and cysteine.

Maillard reaction products (MRPs) derived from rice protein isolate hydrolysate and D-xylose, with or without L-cysteine, were developed as a potential meat flavoring. The combined impact of temperature (80-140 °C) and cysteine on fundamental physicochemical characteristics, antioxidant activity, and flavor of MRPs were investigated through assessments of pH, color, UV-visible spectra, fluorescence spectra, free amino acids, volatile compounds, E-nose, E-tongue, and sensory evaluation. Results suggested that increasing temperature would reduce pH, deepen color, promote volatile compounds formation, and reduce the overall umami and bitterness. Cysteine addition contributed to the color inhibition, enhancement of DPPH radical-scavenging activity and reducing power, improvement in mouthfulness and continuity, reduction of bitterness, and the formation of sulfur compounds responsible for meaty flavor. Overall, MRPs prepared at 120 °C with cysteine addition could be utilized as a potential meat flavoring with the highest antioxidant activity and relatively high mouthfulness, continuity, umami, meaty aroma, and relatively low bitterness.

Application of Maillard Reaction Products Derived Only from Enzymatically Hydrolyzed Sesame Meal to Enhance the Flavor and Oxidative Stability of Sesame Oil.

The low-temperature roasting of sesame oil has become increasingly popular because of its nutritional benefits; however, the flavor is reduced. In order to improve the quality of sesame oil without exogenous addition, sesame meal was hydrolyzed and further used to prepare Maillard reaction products (MRPs) while protease hydrolysis (PH) and glucoamylase-protease hydrolysis (GPH) were used, and their respective Maillard products (PHM and GPHM) were added in the oils for reducing sugar and total sugar content determination, free amino acid determination, and color and descriptive sensory analysis, as well as electronic nose, SPME-GC-MS, odor activity value, and oxidative stability analyses. Results showed that the MRPs could be produced using the enzymatically hydrolyzed sesame meal without exogenous addition, and the oil flavor blended with GPHM (GPHM-SO) was significantly (p < 0.05) improved with the best sensory quality. The composition of pyrazines (119.35 µg/mL), furans (13.95 µg/mL), and sulfur substances (6.25 µg/mL) contributed positively to sensory properties in GPHM-SO, and 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, and 2,3-dimethylpyrazine were characterized as the key flavor compounds with odor activity values of 7.01, 14.80, and 31.38, respectively. Furthermore, the oxidative stability of the oil was significantly improved with the addition of MRPs, and the shelf life of GPHM-SO was predicted to be extended by 1.9 times more than that of the crude oil based on the accelerated oxidation fitting analysis. In general, the MRPs derived only from sesame meal can enhance the flavor and oxidative stability of sesame oil and can be applied in the oil industry.

Research progress of anthocyanin prebiotic activity: A review.

BACKGROUND: Anthocyanins are a kind of flavonoids and natural water-soluble pigments, which endow fruits, vegetables, and plants with multiple colors. They are important source of new products with prebiotic activity. However, there is no systematic review documenting prebiotic activity of anthocyanins and their structural analogues. This study aims to fill this gap in literature. PURPOSE: The objective of this review is to summarize and evaluate the prebiotic activity of anthocyanin's, and discuss the physical and molecular modification methods to improve their biological activities. STUDY DESIGN AND METHODS: In this review, the databases (PubMed, Google Scholar, Web of Science, Researchgate and Elsevier) were searched profoundly with keywords (anthocyanin's, prebiotics, probiotics, physical embedding and molecular modification). RESULTS: A total of 34 articles were considered for reviewing. These studies approved that anthocyanins play an important role in promoting the proliferation of probiotics, inhibiting the growth of harmful bacteria and improving the intestinal environment. In addition, physical embedding and molecular modification have also been proved to be effective methods to improve the prebiotic activity of anthocyanins. Anthocyanins could promote the production of short chain fatty acids, accelerate self degradation and improve microbial related enzyme activities to promote the proliferation of probiotics. They inhibited the growth of harmful bacteria by inhibiting the expression of harmful bacteria genes, interfering with the role of metabolism related enzymes and affecting respiratory metabolism. They promoted the formation of a complete intestinal barrier and regulated the intestinal environment to keep the body healthy. Physical embedding, including microencapsulation and colloidal embedding, greatly improved the stability of anthocyanins. On the other hand, molecular modification, especially enzymatic modification, significantly improved the biological activities (antioxidant, prebiotic activity and so on) of anthocyanins. CONCLUSION: All these research results displayed by this review indicate that anthocyanins are a useful tool for developing prebiotic products. The better activities of the new anthocyanins formed by embedding and modification may make them become more effective raw materials. Our review provides a scientific basis for the future research and application of anthocyanins.

The potential application of vegetable oils in the D-xylose and L-cysteine Maillard reaction system for meaty aroma production.

Vegetable oils with different unsaturated degrees (corn > peanut > olive > palm > coconut) and corresponding enzymatic hydrolysis-thermal oxidation (ENTH) oils were added into D-xylose and L-cysteine Maillard reaction (MR) system, respectively, for potential meaty aroma production. Results indicated that coconut oil and palm oil had lower peroxide, p-anisidine, total antioxidant values, and malondialdehyde content after ENTH and MR. Corn, peanut, and olive oils after ENTH could significantly promote MR because they caused the lower pH, higher reactants depletion, and higher browning degree in the water phase separated from the oil-Maillard reaction system. Additionally, the volatiles were mainly formed from oil phase. Corn, peanut, and olive oils were beneficial to volatiles formation in the oil-MR system due to fatty acid oxidation, especially oleic acid and linoleic acid. Meanwhile, compared to raw oils, adding ENTH oils to the MR system could reduce the content of oxygen, nitrogen, and sulfur-containing heterocycles.

Investigation of acute, subacute and subchronic toxicities of anthocyanin derived acylation reaction products and evaluation of their antioxidant activities in vitro.

Previously, anthocyanins were successfully acylated with lauric acid using Novozym 435 lipase, and the corresponding products were confirmed to have higher stability. As novel synthetic compounds, their toxicological safety has not been evaluated. Therefore, acute, subacute and subchronic toxicities of anthocyanin-lauric acid derivatives (ALDs) were investigated while their antioxidant activities were also evaluated in vitro. The acute toxicity results showed that the 50% lethal dose (LD50) of ALDs in mice was >10 g kg-1. Subsequently, the subacute toxicity test was conducted by oral administration of ALDs at doses of 0.63, 1.25 and 2.50 g kg-1 for 28 days. No adverse effect of ALDs on body weight, food/water intake, organ coefficient and histology was observed. Though there were some fluctuations in AST and ALT, the tested biochemical parameters were maintained within the normal ranges. The subchronic toxicity test results demonstrated that less than 0.60 g of ALDs per kg BW intake did not affect mortality, body weight, food/water intake, gross pathology, histology, hematology and serum biochemistry. Furthermore, cyanidin-3-(6''-dodecanoyl)-glucoside, the main component of ALDs, had a beneficial reducing power and a strong DPPH˙, ABTS+˙, and O2-˙ scavenging activity. This study provides an imperative reference to the safety of ALDs, suggesting their application as novel colorants or antioxidants in food and therapeutics.

Kinetics of Enzymatic Synthesis of Cyanidin-3-Glucoside Lauryl Ester and Its Physicochemical Property and Proliferative Effect on Intestinal Probiotics.

The interest in anthocyanins used in food, cosmetic, and pharmaceutical industries has increased the research in order to improve their stability while maintaining bioactivity. In this work, cyanidin-3-glucoside lauryl ester (Cy3glc-C12) was enzymatically synthesized, using Novozym 435 as a catalyst, as well as to obtain a kinetic model for the bioprocess. Its liposolubility, UV-VIS absorbance property, thermostability, and potential proliferative effect on intestinal probiotics were also studied. The maximum conversion yield (68.7 ± 2.1%) was obtained with a molar ratio (substrate:donor) of 1:56, 435 16.5 g/L Novozym, temperature of 56 °C, and a time of 28 h via the acylation occurred at 6''-OH position of the glucoside. The kinetics of the reaction is consistent with a ping-pong bi-bi mechanism and the parameters of the respective kinetic equations are reported. Compared with native Cy3glc, the liposolubility, pH resistivity and thermostability of Cy3glc-C12 were significantly improved. The growth kinetics of Bifidobacteria and Lactobacillus was established based on the Logistic equation, and Cy3glc-C12 could promote their proliferation especially during the logarithmic growth, in which lower pH and more bacteria population were found compared with those of media without anthocyanins. This research provided a reference for the industrial production of Cy3glc-C12 and extended its application to natural products in lipophilic systems.

Effect of pH regulation on the components and functional properties of proteins isolated from cold-pressed rapeseed meal through alkaline extraction and acid precipitation.

Cold-pressed rapeseed meal with high protein content (38.76% protein dry weight basis) was used to prepare rapeseed protein isolates (RPIs) by alkaline extraction (pH 8.0, 9.0, 10.0, 11.0, 12.0 and 13.0) and acid precipitation (pH 3.0, 3.5, 4.0, 4.5, 5.0 and 5.5). The protein with an intact structure and the highest yield (65.08%) was obtained at extraction pH 9.0 and precipitation pH 4.5, accompanied by the lowest D-amino acid content, the lightest colour and the lowest contents of glucosinolates (2.85 mmol/kg), phytic acid (1.05 mg/g) and sinapine (0.68 mg/g). Additionally, water/oil absorption, foaming and emulsifying capacities decreased with decreasing precipitation pH, while the solubility showed the reverse trend. During gastric simulation digestion, the α-polypeptide of cruciferin and napin in the RPIs showed digestive resistance. Overall, pH regulation might be an effective method to isolate high quality RPIs for use in the food processing industry.

Red raspberry extract (Rubus idaeus L shrub) intake ameliorates hyperlipidemia in HFD-induced mice through PPAR signaling pathway.

Effects of red raspberry extract (RRE) intake on hyperlipidemia mice induced by high-fat diet (HFD) were investigated in this study. After intragastric gavage of RRE for 8 weeks, the body weight and the adipose tissue mass of mice in RRE administration groups significantly (p < 0.05) decreased compared to the group without RRE treatment. RRE treatment significantly (p < 0.05) lowered triglyceride and total cholesterol levels of hyperlipidemia mice. Pparα, Hmgcr, Ldlr, Cyp7a1, Acsl3, Pnpla2 and Pin4 were confirmed as the regulatory genes by transcriptome analysis and qRCR validation. According to KEGG pathway analysis, target genes such as Cyp7a1 and Pin4 were further regulated by the activation of PPARα resulting from RRE supplementation. Meanwhile, liver cholesterol synthesis and conversion were inhibited by the expressions of Hmgcr and Cyp7a1 genes regulated by RRE intake, and Ldlr gene was down-regulated to limit the transport of cholesterol. In addition, RRE treatment could accelerate the conversion from triglyceride to fatty acid. To conclusion, RRE intake would be a protection against diet-induced hypertriglyceridemia.

Potential effects of rapeseed peptide Maillard reaction products on aging-related disorder attenuation and gut microbiota modulation in d-galactose induced aging mice.

As a good flavor enhancer, rapeseed peptide Maillard reaction products (MRPs) were developed, and the effects of MRPs on d-galactose induced aging Kunming mice were investigated for 6 weeks with low (200 mg kg-1 day-1), medium (400 mg kg-1 day-1) and high (800 mg kg-1 day-1) doses. Compared with the natural aging group and d-galactose induced aging mice, the mice with MRP administration showed increases in body weight gain, food intake, organ indexes, feces color and urine fluorescence intensity. MRP intake significantly decreased the MDA content and elevated the activities of CAT, SOD and GSH-Px, and T-AOC in the serum and tissues of the liver, kidney and brain. Additionally, AChE activity was decreased in the brain, while Na+-K+ ATPase and Ca2+-Mg2+ ATPase activity increased in a dose-dependent manner, and decreasing levels of IL-1ß, IL-6 and TNF-α were observed in the liver and kidney. Histopathological analysis suggested an attenuation of inflammatory cell infiltration in the liver and kidney without cell necrosis. High-throughput sequencing results revealed that the ratio of Firmicutes to Bacteroidetes increased in MRP groups, and the pathogenic bacteria were significantly inhibited, while some beneficial bacteria were significantly increased in the intestine. Overall, our results indicated that MRP consumption might have potential beneficial effects on postponing the aging process via reducing the oxidative stress and gut microflora modulation.

Low-pH induced structural changes, allergenicity and in vitro digestibility of lectin from black turtle bean (Phaseolus vulgaris L.).

Lectin was incubated in corresponding acidic buffers (pH 1.0-3.5) for a certain period (0.5, 1, 2, 4, 8, 12 and 24 h) at 25 °C. Low-pH induced changes in structure, allergenicity and in vitro digestibility of lectin from black turtle bean (Phaseolus vulgaris L.) were investigated in the present study. Results indicated that the alteration in structure was a progressive unfolding process mainly depending on pH environment, and the treated lectin attained a stable state at 8 h. Electrophoretic, dynamic light scattering (DLS) and size exclusion chromatography (SEC) analyses suggested that lectin monomers appeared in the solutions of pH < 2.0. Differential scanning calorimetry (DSC) confirmed that thermal stability of lectin weakened in low pH environments. Furthermore, ELISA and in vitro digestion assay showed allergenicity and digestibility significantly decreased with the structural alterations. These results showed low-pH treatments have great potential to reduce the damage of legumes protein consumption.

Potential effects of dietary Maillard reaction products derived from 1 to 3 kDa soybean peptides on the aging ICR mice.

Effects of Maillard reaction products derived from 1 to 3 kDa soybean peptides (MRPF3) on aging ICR mice were investigated. Seven animal groups were established for 5 weeks, including one normal group and six D-galactose (1000 mg kg-1/day) treated groups. Aging control was D-galactose + saline solution, and positive controls were D-galactose + ascorbic acid (Vc) (400 mg kg-1/day) and oligofructose (400 mg kg-1/day), respectively, while the test groups are D-galactose + high (800 mg kg-1/day), medium (400 mg kg-1/day) and low (200 mg kg-1/day) doses of MRPF3. Compared with the aging controls, food intake, body weights and organ indexes returned to normal after feeding with MRPF3, and the color of feces as well as the fluorescence intensity of urine increased. The content of malondialdehyde (MDA) in the liver significantly decreased with the intake of MRPF3, and the activities of SOD and GSH-Px and the total antioxidant capacity of serum significantly increased. The abundance ratio of Bacteroidetes and Firmicutes significantly decreased in MRPF3 groups, and the abundance of Lactobacillus significantly increased, while potentially pathogenic bacteria such as Porphyromonadaceae significantly decreased. Our results showed that MRPF3 might offer a potent retardation potential for aging.

Heating and cysteine effect on physicochemical and flavor properties of soybean peptide Maillard reaction products.

Maillard reaction products (MRPs) were obtained by using the xylose and soybean peptide system through a 2 h heating at pH of 7.6. Cysteine addition and thermal treatment at 80, 100, 120 and 140 °C were investigated via E-nose and E-tongue, free amino acids (FAA) and GC-MS analyses of MRPs. Afterwards, the combined effects were performed using the partial least square regression (PLSR). Results suggested that MRPs without cysteine addition (XSs) had stronger browning intensity, and the cysteine would be beneficial to the pH reduction with heating temperature increasing. PLSR analysis revealed that MRPs with cysteine addition heated at 140 °C (XSC-140) showed the lowest bitterness, and XS-100 had the highest umami and saltiness. Both bitter and umami FAA increased with the addition of cysteine, and more furans and nitrogen-containing compounds formed in the XSs brought caramel-like flavor, while XSCs exhibited meat-like flavor attributed to sulphides generation.

Antioxidant activity and sensory characteristics of Maillard reaction products derived from different peptide fractions of soybean meal hydrolysate.

Four peptide fractions PF1 (>5;kDa), PF2 (3-5;kDa), PF3 (1-3;kDa), PF4 (<1;kDa) were isolated from soybean hydrolysate using the ultrafiltration method. Then, d-xylose and l-cysteine were reacted with specific peptide solution at 120;°C for 2;h, and the molecular weight distribution (MWD), pH, colour, browning intensity, DPPH radical-scavenging activity, free amino acids and sensory characteristics of corresponding Maillard reaction products (MRPF1, MRPF2, MRPF3 and MRPF4) were evaluated, respectively. Peptides with low molecular weight showed higher contribution to the changes of pH, colour and browning intensity during Maillard reaction. The DPPH radical-scavenging activity of PF4 was significantly improved after Maillard reaction. Aroma volatiles and PLSR analysis suggested MRPF3 had the best sensory characteristics with higher contents of umami amino acids and lower of bitter amino acids, therefore it could be deduced that the umami and meaty characteristics were correlated with the peptides of 1-3;kDa.