Maillard reaction products (MRPs) were prepared from casein–glucose by refluxing for 130
min at 102
°C and initial pH 12.0 without pH control to investigate the characteristics of casein–glucose ...Maillard reaction and the antioxidant activity difference among different fractions of MRPs. Browning and intermediate products increased, however, the pH of the system decreased with increase in the heating time. Free amino group content decreased 78% during first 10
min and did not change nearly thereafter. Amino acid analysis indicated that lysine and arginine decreased significantly, and casein was partially hydrolysed to peptides or free amino acid. High molecular weight compounds were dominant in the MRPs, determined by high performance gel-filtration chromatography. After ultrafiltration, antioxidant activity of each MRPs fraction was investigated by DPPH radical-scavenging activity, reducing power, Fe
2+ chelating activity and lecithin oxidation assay. MRPs of different molecular weight exhibited distinctly different antioxidant activities.
In this report, an easy and facile approach for the fabrication of heterogenous, mesoporous nanostructure of graphitic carbon grafted with silane (AEAPTMS) and modified with nanoparticles of Ce and ...Ag, (Ag,Ce@SNC/A1SCA). The graphitization in carbon was induced by ionic liquid-assisted reaction between the glucose and ethylenediamine under mild conditions. It was characterized by thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET), powder X-ray diffraction study (PXRD), ultraviolet–visible spectroscopy (UV-VIS), high-resolution transmission electron microscopy (HRTEM), field emission gun-scanning electron microscopy (FEG-SEM), elemental mapping, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), inductively coupled plasma atomic emission (ICP-AES) and fourier transform infrared spectroscopy (FT-IR). Its acts as an adaptable heterogeneous nanocatalyst in the formation of 3,4-disubstituted isoxazol-5(4H)-one and polyhydroquinoline derivatives. It displayed recyclability for five runs. The recycled catalyst was characterized by PXRD and XPS analysis. XPS analysis established the synergism between metal nanoparticles of Ag and Ce in the prepared nanomaterial.
In this report, a heterogenous, mesoporous nanostructure of graphitic carbon grafted with silane (AEAPTMS) and modified with nanoparticles of Ce and Ag, (Ag,Ce@SNC/A1SCA) was synthesized in a benign manner and characterized. Its catalytic potential was explored in organic transformations such as 3,4-disubstituted isoxazol-5(4H)-one and polyhydroquinoline derivatives. It displayed recyclability for five runs. Display omitted
•Nanocatalyst Ag,Ce@SNC/A1SCA was fabricated.•Graphitic carbon made via assistance of ionic liquid.•It catalyzed synthesis of isoxazol-5(4H)-ones & polyhydroquinolines.•It displayed recyclability for upto five runs.•The recycled catalyst was analyzed by PXRD, FEG-SEM and XPS.
Kokumi is a complex sensation characterized by thickness, mouthfulness and continuity. Kokumi-active peptides, which are distributed in many kinds of food, induce a rich and long-lasting mouthfeel of ...food. Aimed to provide a comprehensive overview of kokumi peptides, this review covers the aspects of preparation and evaluation methods for kokumi peptides, kokumi receptor calcium-sensing receptor (CaSR), as well as structural features of kokumi peptides and derivatives. Apart from extraction and separation from natural and fermented food, preparation of kokumi peptides can be effectively obtained from enzymatic generation. Kokumi peptides are perceived by CaSR in taste cells and the proposed transduction pathway has been described. The evaluation on kokumi-inducing effect of peptides has employed a combination of sensory assessment and CaSR method. The discovered kokumi peptides mainly comprise glutamyl peptides, leucyl peptides and other peptides without specific features. Derivatives of amino acids and peptides including sulphur-containing amino acids, N-acyl-Tyr derivatives, N-acetylated amino acids and Maillard reaction products (MRPs) also work as kokumi enhancers. Based on the summarized developments, great sensory properties and bioactivities enable kokumi peptides as promising protein ingredients in future application.
► Find a new way to improve the antioxidant of whey protein isolate. ► Whey protein isolate (WPI) and seven types of sugars formed MRPs. ► The MRPs exhibited antioxidant activities. ► The MRPs may be ...used as natural antioxidants in food products. ► Study on the changes of the space and molecular of WPI after Maillard reaction.
The objective of this study was to determine antioxidant activities of water-soluble MRPs (Maillard reaction products) from the reactions between whey protein isolate (WPI) and xylose (X), glucose (G), fructose (F), lactose (L), maltose (M) and sucrose (S) at different initial pH values (3, 4, 5, 6, 7, 8 and 9). MRPs derived from the WPI-X system with increasing of pH rendered the highest browning, reducing power and DPPH radical-scavenging activity. SDS–PAGE analyses indicated formation of cross-linked proteins of large molecular mass produced from WPI-X systems. Results of FT-IR analysis indicated that the amide I, II and III bands of WPI from the WPI-X and WPI-G systems were changed by the Maillard reaction. CD spectroscopy showed that β-sheet, β-turns and random coil were increased while the α-helix was decreased after the WPI-G and WPI-X system aqueous solutions were heated. In conclusion, MRPs obtained from the WPI-X system had high antioxidant activity.
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.
•LC-MRPs can effectively inhibit the microbial proliferation in vacuum-packaged sea bass.•LC-MRPs retarded the water migration of vacuum-packaged sea bass.•AFM observation can be used to effectively evaluate the degradation of MPs of vacuum-packaged sea bass.•SAEW pretreatment combined with LC-MRPs has a better preservation effect than single treatment.
Traditional Italian pizza is usually baked in wood-fired or electric ovens at high temperature (> 450ºC) for a short time. However, with the new home-cooking appliances available nowadays, it is ...possible to replicate such baking conditions at home. These conditions favour some chemical pathways, like the Maillard reaction, largely responsible for food attractive sensory qualities such as aroma, taste, and colour. However, high temperature treatments can lead to the formation of undesired compounds like 5-hydroxymethylfurfural and acrylamide. This study aims to evaluate quality attributes, such as cooking weight loss and colour development, and heat-related by-products (Maillard Reaction Products, 5-hydroxymethylfurfural and acrylamide) of pizza baked at high temperature (310°C and 450°C) for increasing baking times in new household cooking appliances. Results are compared to the ones of pizza conventionally home-baked (∼250°C). The collected data provide evidence that it is possible to cook pizza at 450°C using newly developed high-temperature home appliances, achieving quality attributes comparable to those of traditional pizzeria baking; very low levels of heat-induced harmful products are formed, provided that baking time is carefully controlled.
•New homecooking devices can replicate the quality of pizzerias in homemade pizzas.•Baking tests at 310°C and 450°C were carried out and compared to cooking at 250°C.•Pizza colour, MRPs, HMF and AA were determined.•Desirable quality characteristics were obtained by cooking at 450°C.•Low AA and HMF were detected when proper baking time was not exceeded.
Knowledge of the role of peptides in the Maillard reaction is rather limited. In this study, peptide Maillard reaction model systems were established. Volatile and nonvolatile MRPs (Maillard reaction ...products) were investigated by GC‐O‐MS and LC‐MS. Carbohydrate module labeling (CAMOLA) experiments were performed to elucidate the carbon skeleton of these compounds. Results showed that the peptide reaction system generated more pyrazines than the free amino acid group. Several new Amadori‐type conjugates were identified as novel Maillard reaction products that could greatly influence the formation of pyrazines. Our work suggested anew mechanism involving these Amadori‐type conjugates and subsequent investigation revealed that the conjugates could be important intermediate products in the reaction between dicarbonyl and dipeptide. Our findings demonstrate anew pyrazine generation mechanism in the dipeptide Maillard reaction.
Practical Application
We found that a dipeptide Maillard reaction system generated more pyrazines than a reaction system composed of free amino acids. New cross‐linked peptide‐sugar compounds were identified and found to impact the formation of pyrazines. The results of this study may help in the preparation of thermal reaction flavors using enzymatically hydrolyzed vegetable/animal proteins, which contain a considerable amount of peptides, as one of the major reactants.
Bioactive compounds are mostly prone to decomposition during the production process, storage, and severe gastrointestinal conditions. Therefore, their potential application as functional ingredients ...in many food products has opened a new horizon in designing novel food-grade delivery systems. Protein-based delivery vehicles have been extensively applied for this purpose. The stability of such systems is substantially affected by destabilizing conditions such as pH change and high ionic strength, thereby affecting bioavailability and stability of the encapsulated bioactive compound. Protein-polysaccharide Maillard-type conjugates are one of the latest food-applicable carriers and promising attractive methods of delivering nutraceuticals. Recently, these types of carriers have been introduced to improve the bioavailability and stability of nutraceuticals and nutrients and to create novel functional foods. The present paper reviews the most recent potential applications of Maillard conjugates for designing delivery systems; i.e., oil-in-water (O/W) emulsion, nanoemulsion, double emulsions, nanoparticles, nanogels, and microencapsulation. It also highlights the structures/compositions of Maillard conjugates used for delivery in food. Moreover, the gastrointestinal fate of Maillard conjugate-based bioactive-loaded delivery systems has been discussed.
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•Protein-polysaccharide Maillard conjugates are novel carriers in delivery systems.•Maillard conjugates are able to stabilize O/W emulsions and nanoparticles.•Glycated proteins improve encapsulation efficiency of bioactive compounds.•Nutraceutical stability and bioactivity in Maillard based systems are discussed.•Maillard conjugates can be used to fabricate niche foods for obesity treatment.
This review presents recent research conducted on the development of various protein-polysaccharide conjugates, their functional properties and industrial applications. These conjugates are formed by ...the glycosylation of food proteins with carbohydrates via the Maillard reaction and are capable of improving the functional properties of proteins. The Maillard reaction facilitates covalent bonding between a reducing group of a carbohydrate and an amino group of a protein under controlled conditions of temperature, time, pH, and relative humidity. There is a great deal of interest in modifying the functional properties of proteins and in the use of novel conjugates for various industrial applications. This review discusses various methods and their implications for preparing and characterising these conjugates. Furthermore, the physicochemical properties of conjugates such as solubility, thermal stability, emulsifying activity, emulsion stabilising properties, gelling and foaming properties are also analysed. A novel processing technology, a spinning disc reactor, could be an alternative process for the production of protein–polysaccharide conjugates, with desirable functionality in different food systems.
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•A novel process for preparing conjugates via the spinning disc reactor (SDR) has been presented.•Solubility of proteins and their functional properties can be improved significantly by coupling with polysaccharides.•Advances in protein–polysaccharide conjugates by dry and wet heating methods are compared.
Advanced glycation end products (AGEs) formed via the Maillard reaction during the thermal processing of food contributes to the flavor, color, and aroma of food. A proportion of food-derived AGEs ...and their precursors is intestinally absorbed and accumulates within cells and tissues. AGEs have been implicated in the pathogenesis of diabetes-related complications and several chronic diseases via interaction with the receptor for AGEs, which promotes the transcription of genes that control inflammation. The dicarbonyls, highly reactive intermediates of AGE formation, are also generated during food processing and may incite inflammatory responses through 1) the suppression of protective pathways, 2) the incretin axis, 3) the modulation of immune-mediated signaling, and 4) changes in gut microbiota profile and metabolite sensors. In animal models, restriction of dietary AGEs attenuates chronic low-grade inflammation, but current evidence from human studies is less clear. Here, the emerging relationship between excess dietary AGE consumption and inflammation is explored, the utility of dietary AGE restriction as a therapeutic strategy for the attenuation of chronic diseases is discussed, and possible avenues for future investigation are suggested.
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