Formation Of Maillard Reaction Products Research Articles

Influence of infant cereal formulation on phenolic compounds and formation of Maillard reaction products

Infant cereals (IC) are normally the first food provided when the complementary feed period starts. Various IC formulations are available, containing different types and compositions of cereals and other ingredients. The aim of our study is to determine the influence of IC formulation on Maillard reaction products, including furan and acrylamide. The composition of free and bound phenols was also obtained. The furan content detected ranged from 10.3 to 19.5 μg kg−1, and that of acrylamide from inappreciable to 92.4 μg kg−1, with a mean value of 70.5 μg kg−1; for both compounds, the lowest values were obtained for rice IC. Levels of furosine, glucosylisomaltol and acrylamide were mainly influenced by the cereal composition, while those of furan and hydroxymethylfurfural (HMF) were influenced both by cereal composition and by other ingredients. Phenolic composition was strongly influenced by the additional ingredients in the formulation; the largest fraction was that of free phenols. Taking into account the furan and acrylamide exposure, no risk for furan intake was observed; however, significant amounts of acrylamide are ingested when IC with gluten are used.

Effect of different heat treatments on the Maillard reaction products, volatile compounds and glycation level of milk

In this study, the formation of Maillard reaction products and the Maillard reaction sites of milk proteins were studied under different heat treatment conditions. Fifteen samples heated at 75, 90, 105, 120 or 135 °C for 5, 15 or 30 s were selected to investigate the effects of different heat treatment conditions on the Maillard reaction products volatile compounds and protein glycation degree. The contents of fluorescence intensity, furosine, lactulose, and 5-hydroxymethylfural were positively associated with the heat temperature and treatment time. Compared with that of raw milk, the number of glycated proteins increased from 14 to 49 in the milk samples heated at 135 °C for 5 s, and the number of binding sites increased from 47 to 166. These results advance current knowledge about the effect of different heat treatments on the degree of the Maillard reaction and the sensory quality and glycation level of milk.

Effects of processing conditions on hydrolysates of proteins from whole whey and formation of Maillard reaction products

Chemical modifications of proteins during food processing can lead to new functionalities and applications of products. Enzymatic hydrolysis, with Alcalase and Flavourzyme, of whole whey was carried out in different conditions, including pH (5.5, 7.0, and 8.5), temperature (42°C, 50°C, and 58°C), enzyme-substrate ratio (E/S) (1%, 2%, and 3%), and duration (60, 180, and 300 min). The hydrolysates were evaluated for the presence of intermediate and advanced Maillard Reaction Products (MRPs), surface properties, ferric reduction capacity, and content of the redox-active sulfhydryl group. A decrease in the free sulfhydryl group was also observed during whey hydrolysis with both enzymes. This suggested their depletion because of their ability to react with carbonyl compounds generated during MRPs. Of all the variables, pH had the strongest effect on the release of peptides during whey protein hydrolysis, including the enhancement of surface properties, and significantly affected the generation of MRPs and ferric reducing capacity of the hydrolysates. Practical applications Whey protein is a protein source containing all the essential amino acids. Chemical modifications of proteins during food processing can lead to new functionalities and applications of the products. This study demonstrates that processing-induced modifications can enhance the antioxidant capacity of the whey for use as natural preservatives in the food industry. The hydrolytic processes in this study could be used to valorize whole whey and to generate value-added functional ingredients comprising of peptide, Maillard Reaction Products (MRPs) and peptide-MRP adducts. This range of novel products could be applied as antioxidants in the food industry for food preservation and health promotion.

Impact of Chitosan-Genipin Films on Volatile Profile of Wine along Storage

Chitosan-genipin films have been proposed for preservation of white wine, maintaining their varietal key odorants and organoleptic characteristics of sulfur dioxide treated wines. Nevertheless, these wines showed aroma notes that slightly distinguish them. It is possible that during the contact of films with wine for at least 2 months, after fermentation and prior to bottling, interactions or chemical reactions are promoted. In this work, wine model solutions with volatile compounds in contact with chitosan-genipin films were performed to evaluate their evolution along time. To complement these analyses, the volatile compounds of white and red wines kept in contact with chitosan-genipin films during 2 and 8 months were also studied. The results obtained allowed us to conclude that the contact of chitosan-genipin films with both white and red wines tend to retain long carbon chain volatile compounds, such as ethyl hexanoate and octan-3-one. It also promoted the formation of Maillard reaction products, such as furfural by dehydration of pentoses and Strecker aldehydes, such as 3-methylbutanal and phenylacetaldehyde, by degradation of amino acids. This study reveals that the use of chitosan-genipin films for wine preservation is also able to promote the formation of compounds that can modulate the wines aroma, maintaining the varietal notes.

The role of heating time on the characteristics, functional properties and antioxidant activity of enzyme-hydrolyzed rice proteins-glucose Maillard reaction products

This study analyzed the influence of Maillard reaction on the physicochemical, functional properties and antioxidant activity of hydrolyzed rice dreg protein. Maillard reaction between glucose and rice dreg protein hydrolysates produced from various proteases, including trypsin, Neutrase 0.8L and flavourzyme were undertaken. The results of the sodium dodecyl sulfate-polyacrylamide gel electrophoresis and FTIR spectrometer verified the occurrence of Maillard reaction and the formation of MRPs. Analysis on the structure and characteristics of Maillard reaction products (MRPs) at different heating time revealed that the pH of MRPs decreased sharply in the early stage, while the browning intensity of MRPs largely improved. The grafting degree of the MRPs increased to maximum at 90 min and then declined. All amino acids content was decreased with the extended reaction time, and the degradation of lysine and arginine was rapid. The Maillard reaction and the thermal degradation were dominant before and after 90 min, respectively. The solubility of MRPs remained stable independent of the heating time while the emulsifying activity improved at extended reaction time. The MRPs obtained greater antioxidant activity after the Maillard reaction.

Investigations on the formation of Maillard reaction products in sweet cookies made of different cereals

In this study, the content of Maillard reaction products from its initial, intermediate and final stage (5-hydroxymethylfurfural, α-dicarbonyl compounds, furosine, N-ε-carboxymethyllysine and N-ε-carboxyethyllysine) was measured in sweet cookies made of wholegrain flour of eight genotypes of small-grain cereals (bread wheat, durum wheat, soft wheat, hard wheat, triticale, rye, hulless barley and hulless oat) and four corn genotypes (white-, yellow- and red-colored standard seeded corn and blue-colored popping corn). Furthermore, the effect of the initial content of sugars, total proteins, free and total lysine in flour on the formation of Maillard reaction products was investigated using the principle component analysis. 3-deoxyglucosone was the predominant α-dicarbonyl compound in all cereal cookies and the highest content was measured in those made from flour of different colored corn genotypes (on average, 98.35, 151.28 and 172.85 mg/kg after baking for 7, 10 and 13 min, respectively). Heating dough at 180 °C for 7, 10 and 13 min differently affected the content of 5-hydroxymethylfurfural and α-dicarbonyl compounds in the cereal cookies. The 5-hydroxymethylfurfural content gradually increased, while a reduction in 3-deoxyglucosone content was observed in the cookies baked for 13 min except for those made from soft wheat, hulless oat, red- and blue-colored corn. After 7 min of heating, the content of furosine measured in the cereal cookies reached its maximum (from 320.9 mg/kg in yellow-colored corn-based cookies to 585.7 mg/kg in hulless oat-based cookies), while N-ε-carboxymethyllysine and N-ε-carboxyethyllysine showed the opposite trend. The highest content of advanced glycation end products was detected in cookies also made from hulless oat flour rich in proteins (16.80%) and total lysine (10670.3 mg/kg). The interrelationship analysis showed that the initial content of sugars in flour of cereals affected 5-hydroxymethylfurfural and 3-deoxyglucosone formation in the cookies. In addition, a high correlation between protein-bound Maillard reaction products in the cookies and the total proteins and the total lysine content in the flours was found.

Maillard Reaction Products in Gluten-Free Bread Made from Raw and Roasted Buckwheat Flour.

The formation of Maillard reaction products (MRPs) in gluten-free bread made from roasted and raw buckwheat flour was examined. The levels of phenolic compounds such as flavonoids (catechin, naringenin, quercetin, rutin, and others) and phenolic acids (like 4-hydroxybenzoic, caffeic, dihydroxybenzoic, ferulic, gallic, syringic, vanillic, and p-coumaric) were measured using reversed-phase ultra-high performance liquid chromatography-electrospray ionization mass spectrometry (RP–UHPLC–ESI-MS). Early and advanced Maillard reaction products were analyzed using HPLC, whereas spectrofluorimetric analysis was used to determine the levels of fluorescent intermediate compounds (FIC). The total levels of phenolic compounds were higher in the case of buckwheat bread prepared from roasted buckwheat flour (156 and 140 µg/g of crumb and crust, respectively). Rutin, gallic acid, and catechin were the most abundant phenolic compounds detected in roasted buckwheat bread. The roasting process resulted in significantly lower radical scavenging capacities (ABTS) of the total phenolics and flavonoids in the buckwheat bread. Taking into consideration these Maillard reaction products, we observed a significant increase in FIC level in roasted buckwheat crumb and crust (at about 40%, and 38%, respectively). At the same time, the Nε-(carboxymethyl)lysine (CML) level did not change in roasted or raw buckwheat bread crumb, though in roasted buckwheat crust the concentration of CML increased by about 21%.

Maillard reaction products formation and antioxidative power of spray dried camel milk powders increases with the inlet temperature of drying

Demand for camel milk (CM) is increasing worldwide, due to its high nutritious value and health benefits. In this study, whole CM powders were produced by spray drying (SD) at six inlet temperatures (190 °C–250 °C) and by freeze drying (FD). Physicochemical and functional properties of CM powder proteins were investigated. SD at higher inlet temperatures (230 °C–250 °C) resulted in higher extent of Maillard reaction (MR), in comparison to lower temperatures (190 °C–200 °C) and FD treatment. Both treatments had negative effect on casein solubility, while whey proteins remained soluble and slightly increased its solubility with the extent of MR. The CM powders obtained at higher inlet temperatures demonstrated improved antioxidant activity. Secondary structure of whey proteins did not differ among the samples, while surface hydrophobicity of whey proteins was higher in all SD than in FD samples, suggesting only limited denaturation of camel whey proteins at higher inlet temperatures of drying. Thus, the effects of SD under the conditions applied in our study did not decrease camel whey protein solubility, while drying procedure itself regardless of temperature decreased solubility of camel milk caseins. MR generated during CM processing could be an important means of compensating for the lack of antioxidant protection normally associated with β-lactoglobulin but happens to be absent from this milk.

Application of a novel microwave energy treatment on brewers’ spent grain (BSG): Effect on its functionality and chemical characteristics

The effect of a new microwave energy treatment on brewers’ spent grain (BSG) functionality and its application in a bakery product was evaluated. The physicochemical modifications of BSG were studied with special emphasis on the analysis of non-enzymatic browning reactions.Microwave treatment induced the formation of Maillard reaction products with a high antioxidant activity. The structure of these compounds was fully analyzed and it was concluded that melanoidins were formed by polymerization of furanose rings. Results indicated that chlorogenic acids were also reactants involved in the development of this reaction, leading to the formation of new bioaccesible compounds with important antioxidant activity.Although the addition of BSG in cookie formulations negatively affect their texture, this effect was successfully reduced when the microwave treatment was applied on BSG. This was associated to the disrupting effect that the microwaves had on BSG fiber, which significantly reduced its water absorption index (p ≤ 0.05).

Drying methods affect organoleptic and physicochemical properties of rehydrated ginkgo seed slices

Fresh Ginkgo biloba L. seeds (GBS) contain toxic compounds that are deleterious when consumed frequently, but the drying process can reduce its content. In this study, fresh GBS was rehydrated using two steps: dried using different methods (freeze-drying, infrared drying, hot-air drying, and pulse-vacuum drying) followed by rehydration by submerging into water. The influence of drying methods on rehydration kinetics and quality attributes were evaluated. Results showed the Weibull model provided the best fitting for each rehydration curve (Coefficient of determination (R2) > 0.99, residual sum of squares (RSS), reduced chi-square (χ2), and root mean square error (RMSE) closer to zero). Toxic compounds (ginkgotoxin, ginkgolic acid, and cyanide) decreased significantly while total phenolic content (TPC) and total flavonoid content (TFC) increased in rehydrated products compared with fresh GBS. The sensory score was acceptable for all rehydrated products. Besides, rehydrated products showed retention of antioxidant activities and the formation of Maillard reaction products (MRP). Amongst rehydrated products, infrared drying coupled to rehydration stood out being superior with higher TPC, TFC, MRP, and antioxidant activities and lowest enzyme activities, which were again corroborated from the principal component analysis. The present findings will offer more information in selecting the best drying method for GBS's rehydration as a snack, breakfast, or others.

Simultaneous Ultrasound and Heat Enhance Functional Properties of Glycosylated Lactoferrin.

Protein-polysaccharide covalent complexes exhibit better physicochemical and functional properties than single protein or polysaccharide. To promote the formation of the covalent complex from lactoferrin (LF) and beet pectin (BP), we enhanced the Maillard reaction between LF and BP by using an ultrasound-assisted treatment and studied the structure and functional properties of the resulting product. The reaction conditions were optimized by an orthogonal experimental design, and the highest grafting degree of 55.36% was obtained by ultrasonic treatment at 300 W for 20 min and at LF concentration of 20 g/L and BP concentration of 9 g/L. The formation of LF-BP conjugates was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) spectroscopy. Ultrasound-assisted treatment can increase the surface hydrophobicity, browning index, 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free radicals scavenging activity of LF due to the changes in the spatial configuration and formation of Maillard reaction products. The thermal stability, antioxidant activity and emulsifying property of LF were significantly improved after combining with BP. These findings reveal the potential application of modified proteins by ultrasonic and heat treatment.

Effects of phospholipids and reheating treatment on volatile compounds in phospholipid-xylose-cysteine reaction systems

Volatile compound profiles in phospholipid (lecithin and cephalin)-xylose-cysteine reaction systems before and after reheating treatment were determined by solid phase micro-extraction combined with gas chromatography-mass spectrometry to investigate the development mechanism of the warmed-over flavor. The contents of sulfides in the four groups containing added lecithin were significantly higher than those in the other groups, indicating that lecithin had a strong promoting effect on the formation of Maillard reaction products at the intermediate-end stages in the reaction system. The coexistence of phosphatidylcholine and lecithin accelerated the Maillard reaction and fatty acid oxidation. Reheating treatment could promote the simultaneous generation of final-stage Maillard reaction products, the formation of fatty aldehydes, and the reaction of fatty aldehydes with intermediate-stage Maillard reaction products of the mid-stage, which ultimately leads to a decrease in the contents of sulfursulphur-containing Maillard reaction products such as those leading to aroma and an increase in the content of aldehydes in meat and demonstrated good consistency with the results of the sensory evaluation. Odour activity values showed that decanal was the main substance contributing to the warmed-over flavor after reheating treatment in the reaction system. The decrease in meaty flavors, such as 2-methylpentane-3-thiol and furfuryl mercaptan also resulted in flavor deterioration after reheating.

Interrelated Routes between the Maillard Reaction and Lipid Oxidation in Emulsion Systems.

In foods, the Maillard reaction (MR) and lipid oxidation lead to the formation of several molecules through interrelated chemical pathways. MR and lipid oxidation products were investigated in model oil-in-water emulsions consisting of canola oil, water, and Tween 20, a nonionic surfactant, with glucose and phenylalanine. The presence of 1% Tween 20, either in emulsion or as a control surfactant solution, sped up the formation of N-(1-deoxy-d-fructos-1-yl)-phenylalanine and of phenylacetaldehyde. Overall, the formation of MR products was up to sixteen times higher in emulsions than in an aqueous system without a surfactant. The formation of conjugated dienes, total aldehydes, hexanal, and (Z)-2-octenal was reduced down to six times when MR products were present in the emulsion. These results confirm that the formation of MR intermediates is influenced by the reactants' location, and the presence of a discrete nonpolar environment (oil droplets or surfactant micelles) promotes MR volatile formation through Strecker degradation.

Processing temperature and sugar type affect the rate and the extent of proteolysis of a model soy protein isolate system

Processing of ingredients and diets using hydrothermal treatments can lead to negative effects on the nutritional value of proteins, depending on the processing conditions and the matrix of the ingredient or diet. The aim of this study was to evaluate the effects of processing temperature and sugar type on the extent and rate of protein hydrolysis using soy protein isolate as a model system. The experiment utilized a 3☓3 factorial design, with three repetitions per treatment, using autoclaving temperature (not autoclaved, 100 °C, 120 °C) and type of sugar (not added, glucose, xylose) as main factors, also evaluating the interaction between both. Limited formation of Maillard reaction products occurred in the absence of sugars, whilst the addition of xylose increased the formation of MRPs at all processing temperatures. Crosslinks between amino acids (lysinoalanine, lanthionine) occurred with increasing temperatures, with sugar addition being inhibiting. There was a significant interaction (P < 0.01) between the effects of processing temperature and type of sugar for nitrogen solubility, the extent and rate of proteolysis. The effect of autoclaving at 100°C on the rate of protein hydrolysis of the samples without sugars added was as high as the additional effect of autoclaving after the addition of sugars. In contrast, the effect of autoclaving at 120°C on the rate of protein hydrolysis was higher for the samples that contained sugars, compared to those that did not had sugars added. In conclusion, the effect of sugar addition on the extent and rate of proteolysis seems to be dependent on processing temperature, which might indicate different protein damage mechanisms limiting enzymatic protein hydrolysis.

Efficiency of hydrothermal pretreatment on the anaerobic digestion of pelagic Sargassum for biogas and fertiliser recovery

Pelagic Sargassum inundation of coastlines across the North Atlantic Ocean is an ongoing challenge which poses a great threat to economic productivity. This novel study evaluated the valorisation of these invasive seaweeds into biogas and fertiliser using hydrothermal pretreatment and anaerobic digestion technologies. Increasing the severity factor of hydrothermal pretreatment from 1.59 to 3.83 promoted the degradation of organic particulates in Sargassum, resulting in a maximum soluble chemical oxygen demand yield of 27,250 ± 75 mg/L or 237% greater than the unpretreated biomass. However, no linear relationship exists between increased solubilisation and biogas productivity. Peak methane recovery of 116.72 ± 2.14 mL/gVS was achieved at severity factor 2.65 with the decrease thereafter attributed to the formation of Maillard reaction products and inhibitory compounds during hydrothermal pretreatment. The hydrogen sulfide content in the biogas generated also diminished from 3% to 1%. Additionally, the digestate of biogas production is pathogen-free, nutrient-rich and exhibits bio-fertiliser potential.

Black Garlic: Processing, Composition Change, and Bioactivity

Garlic (Allium sativum L.) has been not only consumed as flavor vegetable, but also recorded as a prophylactic and therapeutic medicinal plant since ancient time. Its characteristic pungent flavor limited its application in food product development. Black garlic made from garlic by a thermal processing under certain temperature and relative humidity tastes slightly sweet without pungent flavor, and has extended shelf-life. The present work presented recent development in black garlic processing scheme, composition changes during thermal processing of black garlic, especially formation of Maillard reaction products, and some bioactive properties of black garlic.

Assessment of Healthy and Harmful Maillard Reaction Products in a Novel Coffee Cascara Beverage: Melanoidins and Acrylamide.

Our research aimed to evaluate the formation of Maillard reaction products in sun-dried coffee cascara and their impact on the safety and health promoting properties of a novel beverage called “Instant Cascara” (IC) derived from this coffee by-product. Maillard reaction products in sun-dried coffee cascara have never been reported. “Instant Cascara” (IC) extract was obtained by aqueous extraction and freeze-drying. Proteins, amino acids, lipids, fatty acid profile, sugars, fiber, minerals, and vitamins were analyzed for its nutritional characterization. Acrylamide and caffeine were used as chemical indicators of safety. Colored compounds, also called melanoidins, their stability under 40 °C and in light, and their in vitro antioxidant capacity were also studied. A safe instant beverage with antioxidant properties was obtained to which the following nutritional claims can be assigned: “low fat”, “low sugar” “high fiber” and “source of potassium, magnesium and vitamin C”. For the first time, cascara beverage color was attributed to the presence of antioxidant melanoidins (>10 kDa). IC is a potential sustainable alternative for instant coffee, with low caffeine and acrylamide levels and a healthy composition of nutrients and antioxidants.

Formation of Maillard reaction products in bread crust-like model system made of different whole cereal flours

Free and protein-bound Maillard reaction products (acrylamide, 5-hydroxymethylfurfural, α-dicarbonyl compounds, N-e-fructosyllysine, N-e-carboxymethyllysine and N-e-carboxyethyllysine) and the reaction precursors (sugars and amino acids) were investigated in bread crust-like systems prepared with different cereal flours. Selected cereals were; whole and refined wheat, whole einkorn, whole rye, whole oat and whole corn. For all cereals, the concentrations of reducing sugars, free amino acids and protein-bound lysine increased significantly after dough fermentation (p < 0.05). Heating the bread crust-like model systems at 200 °C for different time periods (5, 15, 30 min) caused significant decrease in the concentration of sugars and amino acids (p < 0.05). Among α-dicarbonyl compounds, 3-deoxyglucosone and methylglyoxal were found in high amounts. However, extended heating time caused significant reduction in their concentrations (p < 0.05). Compared to 5 min of heating, higher amounts of 5-hydroxymethylfurfural formation were observed in samples heated for 15 and 30 min. However, prolonging the heating time resulted in a reduction in the amount of acrylamide formed in bread crust-like samples prepared with einkorn and oats. Heating for 5 min caused formation of early and advanced glycation products in bread crust-like samples prepared from all cereals. The amounts of early and advanced glycation products in the high molecular weight fractions of bread crust-like systems were significantly higher than those in bread-crust-like systems, but they decreased rapidly in samples heated for longer time (p < 0.05).

Effect of Roasting on Flaxseed Oil Quality and Stability

AbstractThe food industry is interested in the application of roasted flaxseeds because the treatment improves their sensory acceptability. However, it also influences flaxseed oil nutritional quality and stability. The aim of the study was to analyze oxidation changes in situ and in flaxseed oil compounds (fatty acids, phytosterols, tocochromanols) and Maillard reaction products (MRP) after roasting. The effect of the roasting temperature (160–220 °C) and flaxseed cultivars (golden‐ and brown‐seed) was taken into consideration. The results showed that the selection of roasting temperature (&lt;200 °C vs. ≥200 °C) and flaxseed cultivar significantly influenced the nutritional quality and oxidative stability of roasted flaxseed oils. The roasting of flaxseeds did not significantly affect the fatty acid profiles of oil but it influenced the content of the other bioactive compounds. As the roasting temperature increased (≥200 °C), the γ‐tocopherol degradation decreased, whereas the content of plastochromanol‐8 increased. The total content of phytosterols in the roasted seed samples was higher than in the raw seeds but there was no correlation between the phytosterol content and roasting temperature. The temperature ≥200 °C significantly accelerated in situ oil oxidation during roasting. On the other hand, these conditions favored the MRP formation, which may have slowed down the dynamics of oil oxidation during storage. There was lower oil oxidation in the brown‐seed cultivar; in consequence, the tocopherol retention was higher than in the golden‐seed cultivars. The results could be useful for the selection of the best cultivars and treatment conditions to decrease unfavorable changes in flaxseed oil nutritional quality and stability.

Monitoring of methylglyoxal/indole interaction by ATR-FTIR spectroscopy and qTOF/MS/MS analysis

Sugar derived reactive 1,2-dicarbonyl intermediates are considered important precursors for the formation of Maillard reaction products. Efficient strategies are needed to modulate their formation in food. Indole a major thermal degradation product of tryptophan, has been shown to scavenge such 1,2-dicarbonyls at high temperatures. In this study, the trapping of methylglyoxal by indole was monitored at various temperatures either by (a) ATR-FTIR spectroscopy or (b) in-solution using qTOF/MS/MS analysis. Information obtained through these studies have indicated that even at room temperature indole can quickly react with methylglyoxal forming an adduct as confirmed by the emergence of a new peak at 1729 cm−1 and by qTOF/MS/MS analysis. On the open surface of the ATR crystal this adduct underwent a fast oxidization into carboxylic acid as evidenced by the disappearance of the band at 1729 cm−1 and the formation of a new band at 1712 cm−1 and its subsequent conversion into a carboxylate band under basic conditions.