Exploring Maillard reaction markers and melanoidins to investigate toxicological and antioxidant profiles of optimized expanded snacks from corn/common bean mixtures.

BACKGROUND: Extrusion cooking of cereal-legume flour mixture is an innovative strategy to introduce nutrient-enriched ready-to-eat snacks to the market. However, this thermal process triggers the formation of compounds that could impact safety aspects of these products. Maillard reaction markers and the end products known as melanoidins were evaluated to assess the toxicological and bioactive profiles of extruded snacks from corn-plus-common-bean-flour combinations. Different molecular weight fractions were isolated and purified to analyze their antioxidant activity and to investigate the role of melanoidins. RESULTS: The snack formulated with an 84:16 ratio of corn:common bean flours exhibited an enhanced toxicological profile. It displayed the lowest levels of acrylamide and furanic compounds, along with reduced blockage of lysine residues in the protein. Extrusion increased the antioxidant activity of uncooked flours (30 to 64%) and total phenolic compounds (26 to 50%), and decreased the available lysine (-72.7 to -79.5%). During the fractionation process, it was established that compounds within the range of 3-10 kDa made the greatest contribution to antioxidant activity. The fraction greater than 10 kDa, which included melanoidins, displayed 7 to 33% lower antioxidant activity. The purification of the fraction greater than 10 kDa revealed that pure melanoidins represented approximately one-third of the antioxidant activity in that fraction. Non-covalent adducts linked to the melanoidin core therefore had a relevant role in the antioxidant action of formulated snacks. CONCLUSION: This investigation illustrates the importance of considering both potential risks and associated benefits of compounds formed during the Maillard reaction while developing new extruded snacks. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Chemical and Biological Characterization of Green and Processed Coffee Beans from Coffea arabica Varieties.

Coffee is one of the most consumed beverages in the world; its production is based mainly on varieties of the Coffea arabica species. Mexico stands out for its specialty and organic coffee. In Guerrero, the production is done by small indigenous community cooperatives that market their product as raw material. Official Mexico Standards stipulate the requirements for its commercialization within the national territory. In this work, the physical, chemical, and biological characterizations of green, medium, and dark roasted beans from C. arabica varieties were carried out. Analysis by HPLC showed higher chlorogenic acid (55 mg/g) and caffeine (1.8 mg/g) contents in the green beans of the Bourbon and Oro Azteca varieties. The caffeine (3.88 mg/g) and melanoidin (97 and 29 mg/g) contents increased according to the level of roasting; a dissimilar effect was found in the chlorogenic acid content (14.5 mg/g). The adequate nutritional content and the sensory evaluation allowed the classification of dark-roasted coffee as premium coffee (84.25 points) and medium-roasted coffee as specialty coffee (86.25 points). The roasted coffees presented antioxidant activity without cytotoxic effects; the presence of CGA and caffeine supports the beneficial effects of drinking coffee. The results obtained will serve as a basis for making decisions on improvements to the coffees analyzed.

Solubility of Cd, Cr, Cu, Ni, and Pb and Its Correlation with Total Polyphenols and Soluble Melanoidins in Hot Infusions of Green and Roasted Mate.

The total and soluble contents of three potentially toxic elements (PTEs) (Cd, Cr, and Pb) and two essential elements (Cu and Ni) in commercial green and roasted mate (Ilex paraguariensis St. Hil.) and their hot infusions were accessed by inductively coupled plasma mass spectrometry. Total polyphenolic (TP) contents in the infusions were accessed by Folin-Ciocalteu method, and the presence of soluble melanoidins (SM) was evaluated by measuring absorbances at 420 nm. The soluble element contents in hot infusions of green mate were present in the following increasing order: Pb < Cd < Cr < Cu, and Ni. For hot infusions of roasted mate, the increasing order was: Cu < Pb < Cd < Cr < Ni. Except for Cr, hot infusions of roasted mate supply lower contents of the soluble PTEs than hot infusions of green mate. Cadmium was the only of evaluated trace element found in hot infusions of green and roasted mate as well as in some of their mate samples above the maximum allowed contents established by Brazilian legislation. Despite this, polyphenol and melanoidin contents in green and roasted mate infusions may reduce Cd bioavailability. The soluble trace elements that correlated directly with total polyphenols in hot infusions of green or roasted mate are indirectly correlated with the presence of soluble melanoidins. Moreover, this is the first study to evaluate the correlations of soluble forms of Cd, Cr, Cu, Ni, and Pb with the presence of SM and TP contents in hot infusions of green and roasted mate.

Gallic Acid Mitigates 5-Hydroxymethylfurfural Formation while Enhancing or Preserving Browning and Antioxidant Activity Development in Glucose/Arginine and Sucrose/Arginine Maillard Model Systems.

The current trend of lowering 5-hydroxymethylfurfural (5-HMF) dietary exposure is challenging since its formation is parallel with the development of food color, flavor and aroma. We aimed to investigate the effect of gallic acid (GA) addition on 5-HMF formation, color development and antioxidant activity (AA) in a series of Maillard Reaction (MR) model systems. The effects of GA addition on browning and AA development were not uniform for all model systems, but always occurred in the same direction, indicating that these phenomena were interconnected. GA mitigated 5-HMF development in four of the nine tested systems, possibly by preventing the oxidation of MR intermediates. Correlation analysis indicated that when GA addition mitigated 5-HMF formation, browning was either promoted or not affected. The proposed strategy was effective for glucose/arginine and sucrose/arginine systems, since GA mitigated 5-HMF formation (49% and 54%, respectively) in addition to increasing color development and antioxidant activity.

Comparison of Phytochemical Profile and In Vitro Bioactivity of Beverages Based on the Unprocessed and Extruded Sesame (Sesamum indicum L.) Seed Byproduct.

In this research functional beverages based on the unprocessed and extruded sesame seeds byproduct were fabricated; phytochemical profile, antioxidant, antidiabetic, and hypoglycemic potential were evaluated. Twenty-four phytochemical compounds were identified in total in both beverages; fourteen of the phytochemical compounds were not modified by the extrusion process. Seventeen of the 24 compounds were identified in the unprocessed sesame seeds byproduct flour beverage-10% (UB10) and 21 in the extruded sesame seeds byproduct flour beverage-10% (EB10). The compounds only identified in UB10 are caffeic acid, luteolin-7-O-glucoside, and isorhamnetin; and in EB10 those compounds were vanillic acid, acteoside, luteolin, quercetin, and melanoidins. No significant difference was observed in the content of total phenolic compounds (TPC) (14.90 and 15.97 mg GAE/100 mL) and total flavonoids (TF) (5.37 and 5.85 mg QE/100 mL). An increase in the biological activity of ESFB10 (IC50: ABTS = 0.19, DPPH = 0.21, α-amylase = 1.01, α-glucosidase = 0.17, DPP4 = 0.11 mg/mL) was observed, compared to UB10 (IC50: ABTS = 0.24, DPPH = 0.31, α-amylase = 2.29, α-glucosidase = 0.47, DPP4 = 0.30 mg/mL). Therefore, the extrusion process had a positive effect, which displayed the highest efficiency inhibiting the free radicals and enzymes related to carbohydrate metabolism.

Potential of green and roasted coffee beans and spent coffee grounds to provide bioactive peptides.

Protein extracts from green and roasted coffee beans and from spent coffee grounds (SCG) were evaluated as bioactive peptides sources. The in silico approach revealed a high frequency of the occurrence (A) of dipeptidyl peptidase-IV (DPP-IV) (0.62) and angiotensin I-converting enzyme (ACE) inhibitor peptides (0.44) in the 11S coffee globulin, which could be released after digestion. After in vitro digestion of the protein, the green bean and SCG proteins were more susceptible to proteolysis, releasing smaller polypeptides (3.4 kDa), which showed higher anti-hypertensive potentials (IC50 = 0.30 and 0.27 mg soluble protein/mL). However, the antioxidant capacity only increased for the roasted coffee and SCG extracts due to antioxidant groups formed during roasting. The heat treatment applied during coffee brewing increased the sensitivity of the SCG extract to proteolysis, leading to their high anti-hypertensive and antioxidant potentials. Therefore, the 11S coffee globulin is a precursor of a series of bioactive peptides.

Isolation and Characterization of Melanoidins from Dulce de Leche, A Confectionary Dairy Product.

Melanoidins, the brown-colored compounds formed through the Maillard reaction, are responsible for color development in dulce de leche (DL), a popular confectionary dairy product in the Río de la Plata region, particularly in Uruguay and Argentina. Color is a critical quality parameter that strongly influences consumer preference. This work aimed to develop a method to perform preliminary structural characterization of the chromophores produced by the Maillard reaction. Melanoidins are present in a water-insoluble fraction, linked to a protein backbone, conforming melanoproteins of high molecular weight. The insoluble melanoprotein fraction (10% total solids) was isolated, and the chromophores released by proteolysis and isolated by gel-permeation chromatography. The analysis of the products revealed that they present a high degree of molecular weight (MW) polydispersity, in a range of 300 to 2000 Da, where the compounds of higher molecular weight contributed the most to the color of the product. The isolated fractions were further analyzed by RP-HPLC using a diode array detector (DAD) detector. These results, together with H-NMR data, suggested that the chromophores isolated belonged to a relatively simple mixture of aromatic products with higher hydrophobic character relative to other products of the melanoprotein digestion.