Maillard Reaction Products Research Articles

Maillard reaction: formation, advantage, disadvantage and control. A review

The Maillard reaction (MR) is often known as the amino-carbonyl reaction, nonenzymatic browning, or protein glycation reaction. The non-enzymatic browning reaction is influenced by several factors like period, quantity of H2O, temperature, involved reactants, pH, and metal ions in food. During the production, processing, and storage of food, the MR is a crucial chemical process. While Maillard reaction products (MRPs) can enhance food quality during processing, some unfavorable reactions can also result in undesirable food effects. There are two sides to MRPs. The positive side is that these products have several advantages such as improvement in color, odor, flavor, and antioxidant ability. On the other hand, the negative side represents decreasing food quality and the nutritional value of some foods, as well as some health-related problems. The review involves several strategies by which MR could be controlled or prevented. These strategies were divided into two parts, the first is non-enzymatic which is done by adding functional ingredients that work to modify reducing sugars and amino groups and/or trapping of α-dicarbonyl compounds. The second is enzymatic, by using enzymes for example, fructosamine kinase, fructosamine oxidase, and lactose oxidase.

Development of Coconut Protein Concentrate-Xanthan Gum Conjugate by Wet-Dry Heating Method for Red Palm Oil Emulsification

Protein-polysaccharide conjugation is commonly achieved by wet and dry heating methods. Therefore, this study aimed to produce red palm oil (RPO) emulsifiers by conjugating coconut protein concentrate (CPC) and xanthan gum (XG) through a combination of wet and dry heating method using a cabinet dryer. Several factors, including reaction time (3, 4, 5, 6, and 7 hours), pH (3, 5, 7, 9, and 11), and protein-polysaccharide ratio (1:3, 1:2, 1:1, 2:1, and 3:1) were evaluated for their effect on the Emulsion Activity Index (EAI) and Emulsion Stability Index (ESI). The ability of the obtaining conjugate to emulsify RPO was evaluated, and the results showed that CPC contained 67.40% protein. Reaction time, pH, and protein-XG ratio had a significant effect on EAI and ESI. Meanwhile, optimal conditions for the formation of the CPC-XG conjugate, based on EAI and ESI, were a reaction time of 5 hours, pH 9, and protein-polysaccharide ratio of 2:1. Fourier Transform Infrared (FTIR) analysis showed that the CPC-XG conjugate had a change in absorption at a wavelength number of around 1640 cm -1 , indicating the presence of a Maillard reaction product. Furthermore, the CPC-XG conjugate used in RPO emulsion has a characteristic EAI value of 23.74 m 2 /g, ESI of 271.32 minutes, a droplet size of 790 nm, and a zeta potential of -36.9 mV. These results suggest that the CPC-XG conjugate produced by the wet-dry heating method has the potential for producing stable RPO emulsions.

Comparison of glycation and glycosylation level between bovine milk-based and goat milk-based infant formula through label-free proteomics techniques

Heat treatment is unavoidable in the processing of infant formula; however, heat treatment causes the proteins to undergo Maillard reaction and form glycation products, which can negatively affect the nutrition and function of the protein. At the same time, glycosylation is a broad post-translational protein modification that is important in a variety of biological processes. However, glycated proteins as well as N-glycoprotein components in infant formula have not been well characterized. Here, a comprehensive comparative analysis of the glycated proteome as well as the N-glycosylated proteome was conducted in both bovine milk-based (BF) and goat milk-based (GF) infant formula. In total, 918 whey proteins were identified from the whey fraction, including 200 glycated proteins and 219 glycosylated proteins. Furthermore, 33 N-glycosylated proteins containing 101 N-glycosylation sites and 64 glycosylated peptides derived from 30 proteins were significantly different (p < 0.05) between BF and GF. Most of the significantly different proteins are associated with innate immunity as well as defense responses. With respect to the differences between BF and GF, ɑ-lactalbumin (LALBA) had higher glycation level in BF than GF; whereas β-lactoglobulin (LGB) had higher glycation level in GF than BF. For glycosylation level, transferin (TF) was highly glycosylated in GF than BF; while serum albumin (ALB) was highly glycosylated in BF than GF. Our results elucidated the proteome, glycated proteome, N-glycosylated proteome in bovine milk-based and goat milk-based infant formulas, which may be useful to researchers in related fields and provide guidance on the improvement of processing technology for infant formula.

Flavor Development of Ground Beef from 3 Muscles, 3 USDA Quality Grades, and 2 Wet-Aging Durations

The objective of this study was to understand the influence of USDA quality grade, muscle, and aging duration on ground beef flavor development. Prime (PR), Low Choice, and Standard quality grade beef subprimals were collected and aged for either 21 or 42 d. Following aging, subprimals were fabricated into gluteus medius (GM), biceps femoris (BF),and serratus ventralis (SV) then ground and formed into patties. Raw patties were designated for proximate composition, fractionated fatty acids, and thiobarbituric acid reactive substances (TBARS). Cooked patties were designated for consumer sensory analysis, volatile compound analysis, and TBARS. Patties were cooked on a preheated griddle to 72°C. All data were analyzed as split-split plot where quality grade served as the whole plot factor, muscle as the subplot factor, and aging duration as the sub-subplot factor. Significance was determined at P&amp;lt;0.05. A quality grade×muscle interaction was observed for moisture, where regardless of muscle, PR subprimals had the lowest moisture percentage (P&amp;lt;0.05). Raw TBARS was not influenced by any interactions or main effects (P&amp;gt;0.05). Individually, the BF and 42 d aged subprimals had the greatest cooked malondialdehyde concentration (P&amp;lt;0.05). Patties from GM aged for 21 d were rated higher for flavor liking compared to GM aged for 42 d and SV aged for 21 and 42 d (P&amp;lt;0.05). GM patties aged for 21 d were rated higher for overall liking compared to GM patties aged for 42 d (P&amp;lt;0.05). Quality grade did not influence any lipid-derived volatile compounds (P&amp;gt;0.05). The SV produced less Maillard reaction products (P&amp;lt;0.05). Aging for 42 d increased lipid-derived volatiles (P&amp;lt;0.05). Consumer liking of aged product is dependent on muscle. Aging recommendations should be muscle-specific to maximize beef eating experience.

Simultaneous determination of advanced glycation end products and heterocyclic amines in roast/grilled meat by UPLC-MS/MS

Advanced glycation end products (AGEs) and heterocyclic amines (HAs) are main harmful Maillard reaction products of meat products. Simultaneous quantification of both with high sensitivity, selectivity and accuracy remains a major challenge due to inconsistencies in their pre-treatment and instrumental methods and the different polarity of AGEs and HAs. We developed a method for the simultaneous determination of AGEs and HAs in roast/grilled meat by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) using dynamic multiple reaction monitoring (D-MRM). The instrument parameters and pre-treatment method were optimized to achieve reasonably good separation and high response for the 11 target analytes within 8 min. From 10 to 200 ng/mL, the limits of detection (LODs) and limits of quantitation (LOQs) ranged from 0.3 to 5.5 μg/L and 0.9 to 6.3 μg/L, respectively, and the correlation coefficient (R2) was >0.99. It was acceptable to recoveries, standard deviations (RSDs), and matrix effects. Six types of roast/grilled meat samples were then tested using the developed method.

Recent advances in molecularly imprinted polymers (MIPs) for visual recognition and inhibition of α-dicarbonyl compound-mediated Maillard reaction products

α-Dicarbonyl compounds (α-DCs) are important intermediates and precursors of harmful Maillard reaction products (e.g., acrylamide and late glycosylation end-products), and they exist widely in thermoprocessed sugar- or fat-rich foods. α-DCs and their end-products are prone to accumulation in the human body and lead to the development of various chronic diseases. Therefore, detection of α-DCs and their associated hazards in food samples is crucial. This paper reviews the preparation of molecularly imprinted polymers (MIPs) enabling visual intelligent responses and the strategies for recognition and capture of α-DCs and their associated hazards, and provides a comprehensive summary of the development of visual MIPs, including integration strategies and applications with real food samples. The visual signal responses as well as the mechanisms for hazard recognition and capture are highlighted. Current challenges and prospects for visual MIPs with advanced applications in food, agricultural and environmental samples are also discussed. This review will open new horizons regarding visual MIPs for recognition and inhibition of hazards in food safety.

Effect of Maillard reaction based on catechol polymerization on the conversion of food waste to humus

The pollution and harm of food waste (FW) are increasingly concerned, which has the dual attributes of pollutants and resources. This study aimed to improve the synthesis efficiency of FW humic substances (HS), and investigating the effect of catechol on the formation mechanism and structure of humic acid (HA) and fulvic acid (FA). Results indicated that catechol incorporation could enable to exhibit higher HS yield and more complex structure, especially the maximum particle size of FA reached 4800 nm. This was due to the combination of catechol with multiple nitrogenous compounds, which accelerated molecular condensation. Spectroscopic scans analysis revealed that Maillard reaction occurs first. Subsequently, Maillard reaction products and amino acids were combined with different sites of catechol, which leads to the difference of molecular structure of HS. The structure of FA is characterized by an abundance of carboxyl and hydroxyl groups, whereas HA is rich in benzene and heterocyclic structures. The structural difference was responsible for the disparity in the functional properties of FA and HA. Specifically, the presence of amino, hydroxyl, pyridine, and carboxyl groups in FA contributes significantly to its chelating activity. This research provides an efficient and sustainable unique solution for the high-value of FW conversion, and provides evidence for understanding the structural evolution of HA and FA.

A Gently Processed Skim Milk-Derived Whey Protein Concentrate for Infant Formula: Effects on Gut Development and Immunity in Preterm Pigs.

Processing of whey protein concentrate (WPC) for infant formulas may induce protein modifications with severe consequences for preterm newborn development. The study investigates how conventional WPC and a gently processed skim milk-derived WPC (SPC) affect gut and immune development after birth. Newborn, preterm pigs used as a model of preterm infants were fed formula containing WPC, SPC, extra heat-treated SPC (HT-SPC), or stored HT-SPC (HTS-SPC) for 5 days. SPC contained no protein aggregates and more native lactoferrin, and despite higher Maillard reaction product (MRP) formation, the clinical response and most gut and immune parameters are similar to WPC pigs. SPC feeding negatively impacts intestinal MRP accumulation, mucosa, and bacterial diversity. In contrast, circulating T-cells are decreased and oxidative stress- and inflammation-related genes are upregulated in WPC pigs. Protein aggregation and MRP formation increase in HTS-SPC, leading to reduced antibacterial activity, lactase/maltase ratio, circulating neutrophils, and cytotoxic T-cells besides increased gut MRP accumulation and expression of TNFAIP3. The gently processed SPC has more native protein, but higher MRP levels than WPC, resulting in similar tolerability but subclinical adverse gut effects in preterm pigs. Additional heat treatment and storage further induce MRP formation, gut inflammation, and intestinal mucosal damage.

Irradiation-induced Maillard reaction with glucosamine: an advance strategy to modify chitosan

In this study, Maillard reaction with glucosamine (GA) induced by gamma irradiation was applied for chitosan (CT) and oligochitosan (OC) to improve the solution stability and antibacterial activity under alkaline condition. The mixture solutions of CT and/or OC with GA were irradiated at the dose of 25 kGy to form the Maillard reaction products (MRPs) respectively. The formations of MRPs were determined by spectrophotometric analyses at the wavelength of 284 nm and 420 nm. The improvement effect caused by the Maillard reaction on the stability of CT and OC solutions in alkaline condition was evaluated through the increase of pH value at the precipitation point of the solutions before and after irradiation. The antibacterial activity of the solutions against Escherichia coli was also investigated. The results showed that the CT-GA MRPs and OC-GA MRPs solutions could be remain their stability at pH 7, and the pH values at the precipitation point were 7.4 and 11.5 respectively. Moreover, at pH 7, the MRPs solutions exhibited high antibacterial activity with the reduction of ~ 4 log CFU/ml over control sample. Furthermore, 5-hydroxymethylfurfural (5-HMF), a known cytotoxic product formed by heat-induced Maillard reaction was not detected in both irradiated CT-GA and OC-GA solution. These results prove that the irradiation-induced Maillard reaction is an effective strategy to modify chitosan, and the MPRs of CT/OS with GA had a great potential to replace synthesis additives as a natural preservative for food applications

Chemosensory of hemp seed oil extracted with hemp seed(Cannabis sativa L.) roasted under various conditions using electronic sensors and GC–MS/Olfactometry

This study analyzed the flavor of six types of hemp seed oil (HSO) extracted with roasted hemp seed (RHS) under various conditions (Raw, 140 °C_9 min, 140 °C_12 min, 160 °C_12 min, 180 °C_6 min). Electronic tongue (E-tongue), electronic nose (E-nose), GC–MS (gas chromatography–mass spectrometry), and GC-O (gas chromatography–olfactometry) were used for HSO flavor analysis. As a result of the E-tongue analysis, the sweetness tends to increase in most samples as roasting. A total of 89 and 77 volatile compounds were detected through E-nose and GC–MS, and the main volatile compounds were identified as Maillard reaction products. A total of 16 odor active compounds were detected in the GC-O analysis, and in the case of 160 ℃_12 min and 180 ℃_6 min, the scent of Roasted hemp seed oil was more dominant than other aroma profiles. The results of this study are basic data on the flavor characteristics of HSO.

Exploring correlations between soy sauce components and the formation of thermal contaminants during low-salt solid-state fermentation

Soy sauce is a traditional seasoning in Asia and provides a unique flavor to food. However, some harmful Maillard reaction products (MRPs) were inevitably formed during the manufacturing process. Fermentation is a critical step of soy sauce manufacturing and has a significant impact on MRPs formation. Therefore, this study investigated the formation of some characteristic MRPs (e.g., furan, carboxymethyl lysine (CML), 5-hydroxymethylfurfural (5-HMF), α-dicarbonyl compounds) and their correlation with major quality indicators (e.g., free amino acids, reducing sugar, total acid, ammonia nitrogen, total nitrogen, non-salt soluble solids) in low-salt solid-state fermentation soy sauce (LSFSS). The result showed that the levels of furan, CML, and 5-HMF continue to increase during the fermentation process, reaching a maximum after sterilization. Further testing using Person correlation showed that the formation of furan, CML, and 5-HMF in LSFSS was positively correlated with glucose, fructose, α-dicarbonyl compounds, and most of the amino acids, while it was negatively correlated with sucrose and methionine. Among them, the contribution of lysine, valine, isoleucine, leucine, and arginine to furan formation has rarely been reported. Our results provide a good theoretical basis for the control of MRPs during LSFSS fermentation.

Maillard reaction products and metabolite profile of plant-based meat burgers compared with traditional meat burgers and cooking-induced alterations

We are undergoing a food transformation with the introduction of plant-based meat analogues, but little is known about their chemical characteristics. This study aimed to elucidate the Maillard reactions in plant-based meat burger alternatives (PBMBA). For this purpose, NMR-based metabolomics and targeted MS analysis of Maillard and dehydroalanine pathway markers were conducted on six PBMBA prototypes with different proportions of high-moisture protein extrudates, low-moisture extrudates and pea protein on a commercial PBMBA and on a meat burger before and after cooking. Results revealed that higher levels of Maillard reaction markers were present in PBMBAs in the uncooked state, with lower levels formed during cooking compared with conventional meat. The metabolite profile disclosed that the distinct pattern of the Maillard reaction could be attributed to different substrate availability, but data also revealed that pre-processing of the plant protein affects the presence of Maillard reaction products in PBMBAs.

Cold-Pressed Okra Seed Oil Byproduct as an Ingredient for Muffins to Decrease Glycemic Index, Maillard Reaction, and Oxidation.

This study aimed to investigate the effects of adding cold-pressed okra seed oil byproduct (OSB) to the muffin formulation, as a partial substitute for wheat flour, on the nutritional, physicochemical, rheological, textural, and sensory properties of muffins. The carbohydrate, protein, oil, moisture, and ash contents of OSB were 44.96, 32.34, 10.21, 7.51, and, 4.98%, respectively, indicating that OSB was rich in protein and carbohydrate. All muffin samples showed a shear thinning behavior, indicating that the viscosity of all samples decreased with increasing shear rate. The frequency sweep test showed that all samples showed viscoelastic solid-like structure [G' (storage modulus)> G″ (loss modulus)]. The K' values (between 66.45 and 139.14) were higher than the K″ values (between 36.62 and 80.42) for all samples. The result was another indication of the viscoelastic solid characteristic of the samples. In our study, it was found that the fluorescence of advanced Maillard products and soluble tryptophan index decreased with increasing amount of OSB, indicating that OSB addition led to a decrease in the amount of fluorescent Maillard reaction (MR) products. The fortified muffins with more than 10% OSB had a reduced estimated glycemic index (GI) significantly in comparison with control muffin samples (p < 0.05). The induction period (IP) values of the muffin samples containing OSB (between 11:57 and 15:15 h/min) were higher than the IP value of the control sample (10:50 h/min), indicating that OSB improved the oxidative stability of the muffin samples. The addition of OSB has shown no negative effect on sensory attributes considering texture, mouth fell, odor, and taste. This study suggested that the addition of OSB in muffins could improve rheological properties and oxidative stability and decrease GI and the amount of MR products without negative impact on sensory properties.

Antioxidant, aroma, and sensory characteristics of Maillard reaction products from Urechis unicinctus hydrolysates: development of food flavorings.

To develop food flavorings with a delicious taste and an anti-oxidation effect, in this study, the glucose Maillard reaction was used for hydrolysates of Urechis unicinctus. The various biological activities of Maillard reaction products (MRPs) and their antioxidant capacity were evaluated. The results showed that the unique fishy odor substances of seafood in MRPs were reduced, indicating that the Maillard reaction improved the flavor of the hydrolysate of Urechis unicinctus. Meanwhile, MRPs exhibited more competitive radical scavenging activities compared to the hydrolysate. Moreover, MRPs demonstrated a considerable potential to protect against 2,2'-Azobis (2-methylpropionamidine) dihydrochloride (AAPH)-induced oxidative stress in a cell model in vitro and in a zebrafish model in vivo. Finally, a novel food flavoring was produced with MRPs as raw material, while the sensory qualities were deemed acceptable. In consequence, during industrial production, MRPs of Urechis unicinctus hydrolysate act as a high-quality raw material for functional flavorings and provide an effective way for the utilization of marine resources.

Unraveling the temporal changes of Maillard reaction products and aroma profile in coffee leaves during hot-air drying

Drying is a critical process that affects chemical compositions, aroma, and quality of tea. Our previous study demonstrated the impact of hot-air drying on the physiochemical properties of coffee leaves. Herein, we investigated changes in carbonyl compounds, volatiles, and their precursors in hot-air dried coffee leaves. The drying process increased the content of 5-hydroxymethylfurfural, glyoxal, and methylglyoxal, while decreasing the levels of free amino acids and sugars. Electronic-nose analysis highlighted an increase in alcohols, aldehydes, and ketones in hot-air dried leaves compared to their freeze-dried counterpart. Using head-space solid-phase microextraction-gas chromatography–mass spectrometry, combined with relative odor activity values, we identified that hexanal, 2-hexenal, α-ionone, and limonene significantly contributed to the grassy, floral, fruity, woody, and citrus flavors of the freeze-dried leaves. In contrast, 1-octen-3-ol and (E,E)-2,4-heptadienal play a key role for the mushroom and nutty aromas of hot-air dried leaves. Additionally, nonanal, (E,Z)− 2,6-nonadienal, and phenylacetaldehyde contributed significantly to the fatty, grassy, rose, and honey aromas of both coffee leaves. Furthermore, interactive network analysis revealed the close correlation between aromas and the levels of alcohols, aldehydes, and ketones. This study provides valuable guidance for production of coffee leaf tea with a prominent aroma while minimizing harmful carbonyl compounds.

Dry-air roasting impact on physicochemical, functional, antioxidant properties, phenolic profile and Maillard reaction products of flaxseed flour and cake flour

The study investigated and compared physicochemical, functional, antioxidant properties, phenolic profile and Maillard reaction products (MRP) of flaxseed flour (FF) and flaxseed cake flour (FCF) upon dry-air roasting (DaR) of flaxseeds at 140, 160 and 180 °C for 5 and 10 min. This information on FF and FCF is limited and has considerable gaps. The raw FF exhibited higher fat, ash, antioxidant and functional properties while lower protein than the FCF. Upon increasing DaR conditions, the ash and protein increased in FCF and decreased in FF. DaR at 180 °C for 10 min augmented water solubility index, ΔE, MRP, free rutin and syringic acid, bound epicatechin, gallic acid and syringic acid while lowered moisture, L*, b*, hue, chroma, potassium, iron, selenium, emulsion indexes, caffeic acid, flavonoids and free resveratrol in FF and FCF. In conclusion, DaR improves phenolic profile, antioxidant properties, MRP, water solubility and oil absorption capacity of FF and FCF.

Effects of slightly acidic electrolyzed water combined with ԑ-polylysine-chitooligosaccharide Maillard reaction products treatment on the quality of vacuum packaged sea bass (Lateolabrax japonicas)

In this study, a new natural preservative, ε-polylysine (ε-PL) and chitooligosaccharides (COS) Maillard reaction products (LC-MRPs), was prepared by Maillard reaction. The preservation effect of LC-MRPs combined with slightly acidic electrolyzed water (SAEW) pretreatment (SM) on vacuum-packed sea bass during refrigerated storage was evaluated. The results showed that after 16 days, SM treatment could effectively inhibit the microbial growth and prevent water migration in sea bass. In addition, the highest water holding capacity (69.79 %) and the best sensory characteristics, the lowest malonaldehyde (MDA) (58.96 nmol/g), trimethylamine (TMA) (3.35 mg/100 g), total volatile basic nitrogen (TVB-N) (16.93 mg N/100 g), myofibril fragmentation index (MFI) (92.2 %) and TCA-soluble peptides (2.16 μmol tyrosine/g meat) were related to SM group. Combined with sensory analysis, we can conclude that the combined treatment of SAEW and LC-MRPs could prolong the shelf-life of sea bass for another 11 days compared with the DW group. Results disclosed that the composite treatment of SAEW and LC-MRPs is a promising technology to improve the shelf-life of vacuum-packed sea bass during refrigerated storage.

Comparative analysis of functional components in Sakekasu (Sake lees)

Background:Sake lees (Sakekasu), a byproduct of sake production, has been recently attracting attention as a functional food. Sakekasu is rich in nutrients and contains glycerophosphocholine (GPC) and S-adenosylmethionine (SAM), which are well-known functional compounds. The content of these compounds in Sakekasu depends on a variety of factors, including fermentation conditions, especially the method and length of ripening. These differences are reflected prominently in the color of Sakekasu, which becomes darker due to the long ripening period and high drying temperature. Objective: This study aimed to clarify the contents of functional components in Sakekasu with different color tones (i.e., ripening period).Methods:Three types of Sakekasu with different color tones (white, ocher, and brawn) were collected from several breweries. The contents of multiple functional components in their extracts were determined by liquid chromatography coupled to high resolution ion-trap/time-of-flight mass spectrometry.Results: Sakekasu with white color had more abundant GPC, SAM, and fatty acids than those with darker color. However, ethyl glucoside and glyceryl glucosides did not differ significantly by color tone. Furthermore, the Maillard reaction products of sugar and dipeptide were mainly found in dark-colored Sakekasu, and their structures were annotated by tandem mass spectrometry.Conclusions:This study has clarified many functional compounds in Sakekasu in relation to color tone (i.e., ripening period) and highlighted the potential of Sakekasu with white color tone as a functional food.Keywords: Sakekasu, functional components, glycerophosphocholine, S-adenosylmethionine, tandem mass spectrometer

Determination of the Maillard reaction products in complementary rice, flour, and noodles by high performance liquid chromatography with a diode array detector

AbstractA method was established for the simultaneous determination of furosine, furanone, and four furfural compounds (5‐hydroxymethylfurfural, furfural, furyl methyl ketone, and methyl furfural) in complementary rice, flour, and noodles for infants and young children by high performance liquid chromatography with a diode array detector. The sample was extracted using oxalic acid aqueous solution as a solvent, and the protein was removed using trichloroacetic acid. Then the six Maillard reaction products were separated by an Eclipse XDB‐C18 column with a gradient elution at a flow rate of 0.6 mL/min using acetonitrile‐0.1% trifluoroacetic acid solution as the mobile phase, detected by a diode array detector and quantified by external standard method. The linear ranges of the six Maillard reaction products were 250–20000 μg/100 g with the correlation coefficients greater than 0.999, and the limits of quantification ranged from 250 to 1000 μg/100 g (S/N ≥ 10). The recoveries of the six Maillard reaction products ranged from 71.2% to 100% with a relative standard deviation of 0.9%–4.9%. The real sample analysis results showed that 5‐hydroxymethylfurfural was detected in two cookie samples, the contents of which were 335 μg/100 g and 436 μg/100 g, respectively. There are no studies on the detection of the six Maillard reaction products in rice, flour, and noodles in the previous reports. The established method provided reference for the quantification of expiration date in complementary rice, flour, and noodles for infants and young children.

Thiamine, cysteine and xylose added to the Maillard reaction of goat protein hydrolysate potentiates the formation of meat flavoring compounds

A protein hydrolysate of goat viscera added with xylose, cysteine, and thiamine under different pH was used to prepare a meat flavoring. Goat viscera hydrolysate and flavoring were subjected to analysis of physicochemical characteristics, amino acid profile, sugars, fatty acids, and volatile profile. Meat aroma characteristics were initiated in the hydrolysate, in which Strecker's pyrazines and aldehydes were identified, which also had fatty acids and amino acids available for the formation of 96 volatile compounds in the flavorings via lipid manipulation, Maillard occurrence, Strecker manipulation and interactions among these means. Maillard reaction products with intense meat aroma, such as 2-methyl-3-furanthiol, 2-furfurylthiol and, bis(2-methyl-3-furyl) disulfide were isolated only in the flavoring at pH 4. In contrast, the flavoring at pH 6 showed a higher concentration than all the other compounds, providing a lower meat characteristic, but an intense sweet, fatty and goat aroma.