Search Results (60)

Dairy products contain complex types and contents of proteins, lipids, and lactose. The Maillard reaction (MR) occurs between proteins and reducing sugars during the processing and storage of dairy products. Maillard reaction products (MRPs) have garnered attention for their potential antioxidant activity. MRPs include melanoidins, reductones, and volatile heterocyclic compounds, which affect flavor and color. Relevant literature was identified through a structured search of PubMed and Web of Science; studies were included if they investigated MRPs in dairy products and reported antioxidant-related outcomes. This review offers a comprehensive overview of the MR in dairy products, systematically investigating the influence of protein, reducing sugars, and their ratios, as well as reaction conditions (process technology, temperature, time, pH, and water activity) on the formation and antioxidant activity of MRPs. The review also covers current applications and the future potential of MRPs as natural antioxidants in dairy products. Although MRPs effectively delay lipid oxidation and enhance stability in dairy products, research on their molecular structure and antioxidant mechanisms remains insufficient. Future research should focus on understanding the multifactorial synergistic effects within the complex dairy matrix, elucidating the molecular structure and extraction of antioxidant substances, and developing regulatory techniques to balance the antioxidant properties of MRPs with the safety concerns of potential harmful byproducts. Full article

This study investigates the use of ozonized water as a novel reaction medium for generating Maillard reaction products (MRPs) from fructose and glycine, comparing their physicochemical properties and antioxidant performance with those produced in phosphate buffer. Heating in ozonized water delayed early Maillard stages, as indicated by slower browning, lower A294 and A420 absorbance, and higher L* values. However, prolonged heating led to intensified reddish-brown coloration and elevated intermediate formation, suggesting ozone-modified reaction pathways. pH declined more sharply in the ozone system, while conductivity increased significantly after 60 min, reflecting accelerated late-stage reactions. Antioxidant activity, assessed via DPPH and ABTS assays, developed more slowly in the ozone system but reached comparable levels to the buffer after 120 min. In emulsion models, MRPs from either system alone exhibited pro-oxidant effects, while blends, especially those produced using ozonized water and buffer at ratios of 75:25 and 50:50, significantly enhanced oxidative stability. Zeta-potential analysis showed that emulsions containing MRP blends had less negative initial charges but exhibited greater stability over 3 days compared to those with individual treatments. These findings highlight the potential of ozonized water to modulate Maillard reaction kinetics and suggest that blending MRPs from different reaction media can enhance antioxidant functionality and emulsion stability in complex food systems. Full article

Collagen peptides derived from fish skin may be limited in food applications due to undesirable flavors. To investigate the effects of Maillard reaction modification on their physicochemical and flavor properties, collagen peptides from tilapia skin were prepared via enzymatic hydrolysis, followed by the Maillard reaction with four reducing sugars (xylose, ribose, glucose and glucosamine) through a combined procedure involving simultaneous enzyme inactivation and Maillard reaction at 100 °C. The resultant Maillard reaction products (MRPs) were characterized by analyzing free amino groups, peptide size distribution and color difference, while the reaction progression was monitored using UV absorption and fluorescence spectroscopy. The flavor profile of MRPs was analyzed through quantitative descriptive sensory evaluation and GC-MS coupled with principal component analysis. Among the four reducing sugars tested, glucosamine-induced Maillard reaction products exhibited the most pronounced physicochemical and sensory improvements. Specifically, glucosamine-MRPs showed the greatest reduction in free amino groups (0.69 μmol/L) and a notable decrease in high-molecular-weight peptides (3.31%), accompanied by an increase in low-molecular-weight fractions. Colorimetric analysis revealed a marked color change (ΔE = 31.78), and spectral analysis further confirmed intensified UV absorbance and fluorescence intensity in the glucosamine group, indicating advanced reaction progression. Sensory evaluation demonstrated a significant reduction in bitterness and enhancement of umami and saltiness. Moreover, GC-MS analysis revealed that the glucosamine-treated group exhibited the most favorable volatile profile, characterized by an increase in aromatic compounds and a substantial decrease in undesirable odorants. This study provides a theoretical basis for controlling the undesirable flavor of collagen peptides through low-extent Maillard reactions by different reducing sugars. Full article

The Maillard reaction (MR), a non-enzymatic interaction between reducing sugars and amino compounds, plays a pivotal role in developing the flavor, color, and aroma of thermally processed foods. Beyond its culinary relevance, the MR gives rise to a structurally diverse array of compounds, including a novel class of fluorescent nanomaterials known as carbon nanodots (CNDs). These Maillard-derived CNDs, although primarily incidental in food systems, exhibit physicochemical characteristics—such as aqueous solubility, biocompatibility, and tunable fluorescence—that are similar to engineered CNDs currently explored in biomedical fields. While CNDs synthesized through hydrothermal or pyrolytic methods are well-documented for drug delivery and imaging applications, no studies to date have demonstrated the use of Maillard-derived CNDs specifically in drug delivery. This review examines the chemistry of the Maillard reaction, the formation mechanisms and characteristics of food-based CNDs, and their potential functional applications in food safety, bioactivity, and future biomedical use. Additionally, it critically evaluates the health implications of Maillard reaction products (MRPs), including both beneficial antioxidants and harmful by-products such as advanced glycation end-products (AGEs). This integrated perspective highlights the dual role of MR in food quality and human health, while identifying key research gaps needed to harness the full potential of food-origin nanomaterials. Full article

Broth cooking is a traditional pretreatment and ripening strategy for high-commercial-value dehydrated marine food, effectively enhancing its texture and rehydration properties. In this work, we characterized the structural information of Maillard reaction products (MRPs) derived from beef scrap stock and investigated their effects on the texture and rehydration performance of dehydrated abalone. The optical and structural properties of the MRPs were analyzed using X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), transmission electron microscopy (TEM), and fluorescence spectroscopy. These MRPs showed osmosis in abalone processing including pretreatment and drying. Low-field nuclear magnetic resonance (LF-NMR) results revealed that MRP pretreatment improved the moisture migration and physicochemical properties of dehydrated abalone. These findings suggest that MRPs, owing to their high osmotic efficiency and nanoscale size, could serve as promising food additives and potential alternatives to traditional penetrating agents in the food industry, enhancing the rehydration performance of dried seafood and reducing quality deterioration. Full article

Grape seeds are a major by-product of the winemaking industry and a great source of bioactive compounds such as polyphenols and proteins. These compounds have a wide range of applications including those in nutraceutical products and cosmetics and within the wine industry itself. Subcritical water extraction (SWE) was explored as a global method to valorize grape seed by-products for their different bioactive compounds in the context of waste valorization, green chemistry (solvent-free extraction), and circular economy. A Box–Behnken design was applied to generate mathematical responses and the ANOVA analysis determined the optimal extraction conditions (pressure, temperature, and time of extraction) for different responses such as total polyphenol content (TPC), antioxidant activity (AA), and total protein (Tprot). Extraction temperature was found to be the most significant factor influencing all responses while pressure had no significant impact on them. Optimal conditions were derived from the mathematical models for each response. For polyphenol extraction, the optimal conditions were as follows: 170 °C and 20 bar for 39 min with 288 mg GAE/g DM. To achieve the highest AA, SWE parameters should be set at 165 °C and 20 bar for 51 min with 332 mg TROLOX/g DM. For the extraction of proteins, it is necessary to work at 105 °C and 20 bar for 10 min (78 mg BSA/g DM) to preserve protein functionality. In comparison, conventional solvent extraction was unable to outperform SWE with values under the SWE results. Given the high content of polyphenols found in the extracts, an HPLC analysis was conducted. The following compounds were detected and quantified: protocatechuic acid (7.75 mg/g extract), gallic acid (6.63 mg/g extract), delphinidin chloride (1.44 mg/g extract), catechin (0.36 mg/g extract), gentisic acid (0.197 mg/g extract), and some epicatechin (0.07 mg/g extract). Additionally, Maillard reaction products (MRPs) were detected at high temperatures, with 5-hydroxymethylfurfural (5-HMF) appearing in extracts processed at 165 °C and above. The presence of MRPs, known for their antioxidant and bioactive properties, may have contributed to the increased AA observed in these extracts. These findings are significant because a solvent-free extraction process like SWE offers a sustainable approach to repurposing winemaking by-products, with potential applications in the wine and food industries. Full article

Background: Maillard reaction products (MRPs) are known for their antioxidant properties; however, their effects on muscle cells remain unclear. This study aims to elucidate the effects of MRPs on muscle hypertrophy and atrophy in C2C12 myotubes. Methods: MRPs were prepared by heating L-lysine and D-glucose, and their antioxidant activity was assessed using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Subsequently, mouse C2C12 myoblasts were cultured with MRPs until myotubes formed, and their diameters were measured to assess hypertrophic and atrophic changes. Akt phosphorylation was evaluated by Western blotting, and gene expression levels were analyzed via quantitative PCR. Results: The prepared MRPs exhibited high antioxidant activity in the DPPH radical scavenging assay. MRP treatment significantly increased the average myotube diameter by approximately 40% and enlarged the largest myotube diameter by up to 80%, potentially mediated by enhanced Akt phosphorylation. Under dexamethasone-induced atrophy, MRPs modestly attenuated the reduction in myotube diameter by approximately 20%, although the effect was not statistically significant, and did not significantly alter the fusion index either. Quantitative PCR analysis revealed that MRP treatment significantly reduced the mRNA expression of Nfe2l2, a key regulator of antioxidant response, whereas it had no notable effects on the expression of genes related to myoblast proliferation (Myod1), differentiation (Myog), hypertrophy (Igf1), atrophy (Foxo1 and Trim63), and oxidative stress (Cat, Gclc, and Nqo1). Conclusions: Our findings suggested that MRPs possess antioxidant activity and promote myotube hypertrophy via Akt signaling. This study highlighted the potential of MRPs as functional ingredients for promoting muscle health, though further in vivo studies are required to validate their physiological relevance. Full article

Garlic (Allium sativum L.) is well known for its numerous health benefits; however, its strong flavor and aroma may limit its consumption due to gastrointestinal discomfort. This study aimed to evaluate puffing as a novel garlic processing method and compare the properties of puffed garlic with those of raw and black garlic (BG). Puffing was applied at different pressures after adjusting moisture content, resulting in significant physicochemical changes, including increased browning and the development of a porous, crunchy texture. In contrast, BG exhibited a black coloration and a gelatinous texture. Puffing resulted in a marked improvement in extraction yield (except at 196 kPa) and an increase in Maillard reaction products (MRPs), which correlated with the intensity of browning. Although the total phenolic content (TPC) and total flavonoid content (TFC) increased three-fold and eight-fold, respectively, compared to raw garlic, the antioxidant activities determined by DPPH and ABTS radical scavenging activities increased by 22-fold and 61-fold, respectively, compared to raw garlic. All garlic samples demonstrated anti-inflammatory activity, with puffing pressure significantly influencing the suppression of IL-6 production. While BG is widely recognized for its enhanced health-promoting properties, puffed garlic exhibited comparable antioxidant and anti-inflammatory benefits in a shorter time frame and with a better retention of garlic’s original flavor. These findings highlight puffing as an efficient and promising alternative to traditional garlic processing, enhancing functionality while reducing sensory drawbacks. Full article

Processed brown sugar is produced by combining non-centrifugal cane sugar (NCS), raw sugar, and molasses. The present study aimed to examine the effects of NCS and raw sugar blending (10%:90%, 50%:50%, 75%:25%, and 90%:10%) on color traits, non-volatile and volatile compounds, retronasal aroma release, and sensory profiles of processed brown sugar, and hence, its flavor quality. The International Commission for Uniform Methods of Sugar Analysis (ICUMSA) color index and the +L* (brightness) and +b* (yellowness) color spaces were gradually altered upon the addition of raw sugar, with strong Pearson’s negative correlations between the ICUMSA value and both color space indices (r = −0.9554 and r = −0.9739, respectively), causing a lighter color of the final product. Raw sugar addition also significantly reduced the concentration of non-volatile compounds, such as glucose and organic acids (p < 0.05). As the raw sugar proportion increased from 10 to 90%, the concentrations of total volatile compounds and Maillard reaction products (MRPs), such as pyrazines, furans, and furanones, also decreased significantly from 62.58 to 22.73 µg/100 g and 34.75 to 6.80 µg/100 g, respectively. Reduced intensities of ion masses of in-mouth and in-nose retronasal odors from volatile MRPs, as well as roasted aroma and richness properties, were observed in processed brown sugars with greater raw sugar content. Taken together, a higher proportion of raw sugar in processed brown sugar manufacturing enhances brightness while reducing acidity and aftertaste; however, increased NCS content results in darker products with greater roasted aroma and richness, affecting flavor quality. Full article

This study evaluated the physicochemical characteristics, antioxidant properties, and consumer acceptance of a traditional Korean snack nurungji blended with barley (Hordeum vulgare L.). The antioxidant activity of β-glucan was identified in barley using a model Maillard reaction products (MRPs) system. Nurungji samples were analyzed based on barley cultivars (waxy and hulled), barley blending ratios (0, 25, 50, 75, and 100), and cooking equipment (electric and electric pressure rice cooker). Nurungji blended with waxy barley and cooked using an electric pressure rice cooker showed a significant increase in antioxidant properties, such as 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activities, ferric reducing antioxidant power, and reducing power. The antioxidant activity of the model MRP solutions increased according to heating time and the addition of β-glucan. In the consumer acceptance test, nurungji blended with 50% barley showed a significantly higher acceptance rate in terms of overall evaluation, aroma, taste, texture, aftertaste, and purchase intents. Full article

The Maillard reaction (MR) is a key process in food science, producing bioactive compounds with antioxidant properties. This study evaluates the antioxidant potential of MR products (MRPs) from different dairy byproducts—cow cheese whey, goat cheese whey, and cow yoghurt whey—highlighting their applicability in food preservation and waste valorisation. Whey samples were subjected to the MR at 140 °C for 90 min, showing significant amino acid and sugar consumption, particularly arginine, histidine, and lactose. Using a library of potential antioxidant MRPs (molecular weight < 250 Da), 28 key compounds, including 2-pyrrolecarboxaldehyde and maltol isomer, were identified, primarily in cow cheese whey. A complementary high-molecular-weight MRP library (≥250 Da) identified 72 additional antioxidant compounds, with distinct production patterns linked to whey type. Multivariate analyses confirmed that whey type strongly influences MRP profiles. These results highlight the potential of MR to transform whey by-products into valuable sources of natural antioxidants. This approach offers sustainable strategies for enhancing food preservation, reducing food waste, and supporting the targeted use of MRPs in the food industry. Full article

The Maillard reaction (MR) between sugars and amino acids, peptides, or proteins is understood to occur gradually during the production and aging of sparkling wines, where it contributes to caramel, roasted, and toasted aromas. Divalent metal ions can accelerate the MR, although this has not been previously reported in wine or wine-like conditions. In this work, the effect of calcium (Ca) and magnesium (Mg) ions on the concentration of 10 Maillard reaction-associated products (MRPs) was measured in modified sparkling base wine during accelerated aging at 50 °C for four weeks. Chardonnay base wine was modified by the addition of fructose (0.02 M) and a single amino acid (lysine, glycine, cysteine; 0.01 M) in combination with Ca²⁺ or Mg²⁺ at zero, low (10 mg/L), or high (50 mg/L) dose levels. MRPs were quantified by headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME-GC/MS), sugar concentration was measured by enzymatic assay, and amino acids and free metal ions were monitored by capillary electrophoresis. Fructose levels did not substantially decrease during aging despite increases in all MRPs, suggesting that trace sugars or α-dicarbonyl species present in the wine matrix likely play a greater role in MRP formation than fructose. Aging duration and amino acid content had a greater effect than metal addition on the composition of the MRPs. Treatments containing cysteine and 50 mg/L Ca²⁺ had elevated concentrations of benzaldehyde and furfural ethyl ether following 4 weeks of accelerated aging. This work identified key MRPs that increase during base wine accelerated aging and informs future research on the relationship between wine composition and aging markers. Full article

The effects of puffing on the ginsenoside composition as well as antioxidant and anti-inflammatory activities of ginseng berry were investigated to increase the utilization of ginseng berry. There was no significant difference in extraction yield between the control and puffed samples at all moisture contents and pressure conditions (p < 0.05). Major ginsenosides of ginseng berry (especially ginsenoside Re) were degraded through deglycosylation and dehydration by heat and pressure, and new minor ginsenosides (Rg3, F2, Rh2 and Rb2) were produced after puffing. Puffed ginseng berries showed higher total phenolic content (TPC), total flavonoid content (TFC) and Maillard reaction products (MRPs) than those of the control group, and these contents were increased as puffing pressure increased. In addition, higher antioxidant activities were observed in puffed ginseng berries compared to the controls, possibly due to the increase in TPC and MRPs. Antioxidant activity increased with increasing puffing pressure at all moisture contents. Nitric oxide (NO) production showed no significant inhibitory effect between control and puffed ginseng berries (p < 0.05). In the case of inflammatory cytokines, IL-6 had an inhibitory effect, but TNF-α had no inhibitory effect. Consequently, puffing showed a positive effect on the composition and the transformation of ginsenosides as well as the antioxidant activity of ginseng berries, suggesting that puffed ginseng berries can be used as a high value-added food material. Full article

The Maillard reaction (MR) involves interactions between reducing sugars and amino acids or proteins during heating, producing Maillard reaction products (MRPs) that influence food flavour, aroma, and colour. Some MRPs exhibit antioxidant properties, prompting interest in their potential as natural food preservatives. This study aimed to develop a method for detecting and identifying antioxidant MRPs using high-pressure liquid chromatography (HPLC) coupled with high-resolution mass spectrometry (HRMS). By improving chromatographic conditions, the separation of antioxidant MRPs was optimised using known antioxidant MRPs as reference signals. This work also examined the effects of pH, reaction time, and different sugar–amino acid combinations on the production and composition of antioxidant MRPs. Results indicated that neutral to basic pH facilitated faster reactions, with pH 7 selected as optimal. A library of 50 m/z signals for potential antioxidant MRPs was created, and the best combinations of amino acids and sugars for their production were identified. These findings pave the way for more precise analyses of antioxidant MRPs, with future research focusing on isolating and characterising specific MRPs to understand their structures and mechanisms, ultimately contributing to the development of functional foods with natural antioxidant properties. Full article

The organic selenium (Se), particularly in the form of selenoamino acids, in non-edible sections or by-products of Se-enriched plants, has the potential to generate Maillard reaction products (MRPs) during thermal treatment or fermentation. To elucidate the recycling process of organic selenium in foods and improve the utilization rate of Se, the biotransformation of organic selenium was studied by the cultivation of edible radish sprouts with Se-MPRs. Maillard reactions were simulated using selenoamino acids (SeAAs; selenomethionine and methylselenocysteine) and reducing sugars (glucose and fructose) for preparing Se-MRPs. The structures of the possible dehydrated Se-MRPs were analyzed using a HPLC-ESI-MS/MS system based on their fragmentation patterns and Se isotopic characteristics. Se absorption by the radish sprouts cultivated using Se-MRPs was estimated by the corresponding Se in the SeAAs and the total Se contents. The capabilities of SeAA transformation and total Se assimilation by the sprouts were related to the substrate composition during the Se-Maillard reaction. A particular Se-MRP (selenomethionine + fructose) increased SeAAs transformation by 33.8% compared to selenomethionine. However, glucose and fructose seemed to inhibit the transformation of the Se-MRPs to SeAAs by 10.0 to 59.1% compared to purified Se-MRPs. These results provide key references for the efficient utilization of organic Se in the cultivation of Se-enriched sprouts. Full article