Biological Properties of Melanoidins: A Review

Novel enhancement of interfacial interaction and properties in biodegradable polymer composites using green chemically treated spent coffee ground microfiller

This study investigates the potential of utilizing green chemically treated spent coffee grounds (SCGs) as micro biofiller reinforcement in Poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) biopolymer composites. The aim is to assess the impact of varying SCG concentrations (1 %, 3 %, 5 %, and 7 %) on the functional, thermal, mechanical properties and biodegradability of the resulting composites with a PHBV matrix. The samples were produced through melt compounding using a twin-screw extruder and compression molding. The findings indicate successful dispersion and distribution of SCGs microfiller into PHBV. Chemical treatment of SCG microfiller enhanced the interfacial bonding between the SCG and PHBV, evidenced by higher water contact angles of the biopolymer composites. Field Emission Scanning Electron Microscopy (FE-SEM) confirmed the successful interaction of treated SCG microfiller, contributing to enhanced mechanical characteristics. A two-way ANOVA was conducted for statistical analysis. Mass losses observed after burying the materials in natural soil indicated that the composites degraded faster than the pure PHBV polymer suggesting that both composites are biodegradable, particularly at high levels of spent coffee grounds (SCG). Despite the possibility of agglomeration at higher concentrations, SCG incorporation resulted in improved functional properties, positioning the green biopolymer composite as a promising material for sustainable packaging and diverse applications.

Biochemical Profiling and Physicochemical and Biological Valorization of Iraqi Honey: A Comprehensive Analysis

Our study aimed to analyze five monovarietal honeys from the Salah Eddine region in Iraq, focusing on physicochemical, antioxidant, and antimicrobial properties and polyphenolic compounds. Our objective was to evaluate the strengths and qualities of Iraqi honeys, ensuring compliance with the Codex Alimentarius standard for honey. The spectrophotometric analysis included assessments of reduced sugar (75.8-77.7%), fructose-to-glucose ratio (0.7-0.9%), sucrose (2.2-2.9%), HMF (17.23-18.87 mg/kg), and melanoidin content (0.25-0.44), which were all determined. The electrical conductivity (0.39-0.46 mS/cm) using a conductivity meter, pH (4.02-4.31), and mineral composition were determined in all samples using atomic absorption spectrometry. Antioxidant activities were spectrophotometrically determined, through DPPH free radical scavenging (7.87-95.62 mg/mL), as was the total antioxidant activity (14.26-22.15 mg AAE/g), with correlations established with biochemical constituents such as the total phenol content, highlighting the significant presence of Coumaric acid (0.38-2.34 µg/mL), Catechin (1.80-2.68 µg/mL), and Quercetin (0.30 µg/mL) using HPLC. The study also observed notable antimicrobial activities using Escherichia coli, Staphylococcus aureus, and Candida albicans on Mueller-Hinton agar as well as through diffusion technique. In conclusion, our findings, including the antioxidant and antimicrobial strengths, underscore the substantial potential of Iraqi honeys in mitigating damage and preventing the onset of various diseases, affirming their good quality and adherence to international honey standards.

Bioactive profile and microbiological safety of Coffea arabica and Coffea canephora beverages obtained by innovative cold extraction methods (cold brews)

Coffee cold brews have been gaining prominence and popularity among consumers worldwide. However, only a few studies have systematically analyzed their chemical composition or evaluated microbiological safety aspects. This study aimed to evaluate the survival of Bacillus cereus and Escherichia coli in cold brews prepared from roasted and ground Coffea arabica and C. canephora seeds using the following preparation methods: immersion without filter (INF), immersion in a cotton filter bag (ICF), vacuum (Vac.) and cold dripping (Drip.). Traditional hot dripping methods using filter paper (HDFP) and cotton filter (HDCF) were also tested for comparison. Water at 4 °C or 25 °C was intentionally contaminated (105 CFU/mL) with cells of Escherichia coli ATCC 25922 (EC) and Bacillus cereus F4433 (BC) before coffee extraction and refrigeration at 4 °C. Coffee concentrations of 5, 10, and 15% were tested. Analyses of pH, soluble solids, nine chlorogenic acids and two lactones (CGA), caffeine, trigonelline, and melanoidins were performed. Results were compared by ANOVA, followed by the Fisher's test, Pearson correlation, Variable Importance in Projection (VIP), and Cluster analyses, with a significance level of 5%. EC and BC were not detected (<10 CFU/mL and < 1 CFU/mL, respectively) after preparing C. arabica and C. canephora hot brews. In cold brews, the higher the extraction of soluble solids and bioactive compounds (with the highest occurring at 25 °C), the lower the counts of inoculated microorganisms during 24 h of storage. BC was not detected after 24 h of extraction and/or storage in the drinks obtained by ICF and Drip. at 5%, 10%, and 15% and INF and Vac. at 15%. EC was not detected in ICF and Drip. at 10 and 15%, and in INF at 15%. C. canephora brews exhibited higher levels of soluble solids, CGA, caffeine, and melanoidins than C. arabica brews. Based on these results, it can be concluded that in the absence of thermal processing as in hot brews, more concentrated cold brews, such as 15%, produced at 25 °C by dripping and immersion methods, are preferable for later dilution due to the higher content of soluble solids and bioactive compounds that contribute reducing the number of microorganisms in the beverage.

Spent coffee grounds as feedstock for the production of biosurfactants and the improved recovery of melanoidins

Spent coffee grounds (SCG) are wastes generated in high amounts worldwide. Their composition makes them a promising feedstock for biotechnological processes. Here we show that the production of the biosurfactant surfactin by submerged culture of a Bacillus subtilis strain growing on SCG is possible, reaching concentrations up to 8.8 mg/L when using SCG at 8.3 g/L in the medium. In addition, we report a synergy between the production of surfactin and the recovery of melanoidins, an added-value compound already present in SCG. More specifically, the concentration of melanoidins in the culture medium increased between 2.1 and 2.5 times thanks to the presence of the B. subtilis in the culture. Furthermore, we have observed a strong interaction between surfactin and melanoidin aggregates through dynamic light scattering measurements, and that both of them can be co-purified with an acid precipitation. We have also characterized the interfacial and antioxidant properties of the cell-free supernatant and surfactin extract, as well as the distribution of the congeners of the biosurfactant. Altogether, this work describes a promising approach to obtain biosurfactants and antioxidant molecules in a single operation, which can be used to design several new formulations of interest for bioremediation, amendment of soils, food and cosmetics.

Spray-Drying Impact the Physicochemical Properties and Formation of Maillard Reaction Products Contributing to Antioxidant Activity of Camelina Press Cake Extract

Spray-drying is one of the most popular techniques in the food industry for converting liquid material from a fluid state into a form of dried particles to produce encapsulated or instant products. Instant products are considered as convenient foods; moreover, the goal of encapsulation is to close the bioactive compounds in a shell, preventing them from being affected by environmental factors. The purpose of this study was to examine the influence of spray-drying conditions, in particular three inlet temperatures, on the physicochemical and antioxidant properties of powders obtained from Camelina Press Cake Extract (CPE). The CPE was spray-dried at 140 °C, 160 °C and 180 °C. The solubility, Carr and Hausner Indexes, tapped densities and water activity of the powders were analyzed. The structural changes were also detected using FTIR spectroscopy. Additionally, the characteristics of the initial and reconstituted samples and their rheological properties were evaluated. The antioxidant potential, total polyphenols and flavonoids content, free amino acids, and the Maillard reaction products contents in the spray-dried powders were also evaluated. The results indicate a cascade of changes between the initial and reconstituted samples, and important changes in the bioactive potential of samples. The inlet temperature significantly influenced the solubility, flowability and particle sizes of the powders, as well as Maillard products formation. The results of the rheological measurements illustrate the changes after the reconstitution of extracts. This study indicates the optimal parameters of CPE spray-drying, those that yield favorable physicochemical and functional values, which may open up a promising path for CPE valorization, indicating its potential and the possibilities of its use.

Bioaccessibility of Maillard Reaction Products from Biscuits Formulated from Buckwheat Flours Fermented by Selected Lactic Acid Bacteria

The in vitro bioaccessibility of the soluble protein and Maillard reaction products (MRPs) such as furosine (an early indicator of the MR), free FIC (fluorescent intermediate compounds), and FAST index (fluorescence of advanced MRPs and tryptophan), and the level of melanoidins defined by the browning index were analyzed in biscuits formulated from raw and roasted common buckwheat flours fermented by select lactic acid bacteria (LAB). The content of soluble proteins in fermented buckwheat flour and biscuits before and after digestion in vitro was significantly dependent on the LAB applied and the type of flour used and was the highest in the digested biscuits, indicating increased bioaccessibility. Generally, in all analyzed biscuits a lower furosine content was observed as compared to control samples, and its high bioaccessibility was noted after digestion. The free FIC in biscuits was strain-dependent, resulting in low bioaccessibility with the exception of biscuits obtained from both types of flours fermented by Streptococcus thermophilus MK-10. Compared to control biscuits obtained from raw buckwheat flour, the almost twice-increased FAST index was found for samples fermented by L. plantarum IB or Streptococcus thermophilus MK-10. After digestion, at least a fivefold higher value of the browning index was noted in control and tested biscuits, indicating the high bioaccessibility of melanoidins. This study indicates that fermentation of buckwheat flours by selected lactic acid bacteria seems to be a good way to obtain a product with high bioaccessibility of MRPs. However, further research on their functional properties is needed.

Honey's Antioxidant and Antimicrobial Properties: A Bibliometric Study

Research attention has been drawn to honey's nutritional status and beneficial properties for human health. This study aimed to provide a bibliometric analysis of honey's antioxidant and antimicrobial properties. The research advancements within this field from 2001 to 2022 were addressed using the Scopus database, R, and VOSviewer. Of the 383 results, articles (273) and reviews (81) were the most common document types, while the annual growth rate of published manuscripts reached 17.5%. The most relevant topics about honey's antimicrobial and antioxidant properties were related to the agricultural and biological sciences, biochemistry, and pharmacology. According to a keyword analysis, the most frequent terms in titles, abstracts, and keywords were honey, antimicrobial, antioxidant, bee, propolis, phenolic compounds, wound, antibacterial, anti-inflammatory, and polyphenols. A trend topic analysis showed that the research agenda mainly encompassed antioxidants, pathogens, and anti-infection and chemical agents. In a co-occurrence analysis, antioxidants, anti-infection agents, and chemistry were connected to honey research. The initial research focus of this domain was primarily on honey's anti-inflammatory and antineoplastic activity, wound healing, and antibacterial agents. The research agenda was enriched in the subsequent years by pathogens, propolis, oxidative stress, and flavonoids. It was possible to pinpoint past trends and ongoing developments and provide a valuable insight into the field of honey research.

Beer and Microbiota: Pathways for a Positive and Healthy Interaction

Beer is one of the most consumed drinks worldwide. It contains numerous categories of antioxidants, phenolic products, traces of group B vitamins, minerals (selenium, silicon, potassium), soluble fibers and microorganisms. Low or moderate beer consumption, with or without alcohol, showed positive effects on health by stimulating the development of a healthy microbiota. In the present review we focused on four components responsible with interaction with gut microbiota: microorganisms, polyphenols, fiber and melanoidins, their presence in usual beers and on perspectives of development of fortified beers with enhanced effects on gut microbiota. Though microorganisms rarely escape pasteurization of beer, there are new unpasteurized types that might bring strains with probiotic effects. The polyphenols from beer are active on the gut microbiota stimulating its development, with consequent local anti-inflammatory and antioxidant effects. Their degradation products have prebiotic action and may combat intestinal dysbiosis. Beer contains dietary fiber such as non-starchy, non-digestible carbohydrates (β-glucans, arabinoxylans, mannose, fructose polymers, etc.) that relate with gut microbiota through fermentation, serving as a nutrient substrate. Another type of substances that are often considered close to fiber because they have an extremely low digestibility, melanoidins (melanosaccharides), give beer antioxidant and antibacterial properties. Though there are not many research studies in this area, the conclusion of this review is that beer seems a good candidate for a future functional food and that there are many pathways by which its ingredients can influence in a positive manner the human gut microbiota. Of course, there are many technological hinderances to overcome. However, designing functional beers fortified with fiber, antioxidants and probiotics, with a very low or no alcoholic content, will counteract the negative perception of beer consumption, will nullify the negative effects of alcohol, while simultaneously exerting a positive action on the gut microbiota.

Bioactive compounds as an alternative for the sugarcane industry: Towards an integrative approach

Here, a comprehensive review of sugarcane industrialization and its relationship with bioactive compounds (BCs) detected in various products and by-products generated during its processing is presented. Furthermore, it is discussed how these compounds have revealed important antioxidant, antineoplastic, antidiabetic, and antimicrobial activities. From this bibliographic research highlights the significance of two types of BCs of natural origin (phenolic compounds (PCs) and terpenoids) and a group of compounds synthesized during industrial transformation processes (Maillard reaction products (MRPs)). It was found that most of the studies about the BCs from sugarcane have been conducted by identifying, isolating, and analyzing ones or a few compounds at a specific period, this being a conventional approach. However, given the complexity of the synthesis processes of all these BCs and the biological activities they can manifest in a specific biological context, novel approaches are needed to address these analyses holistically. To overcome this challenge, integrating massive and multiscale methods, such as omics sciences, seems necessary to enrich these studies. This work is intended to contribute to the state of the art that could support future research about the exploration, characterization, or evaluation of different bioactive molecules from sugarcane and its derivatives.

Evaluation of Melanoidin Contribution to Colour Characteristics of Brewing Products

The article focuses on the issue of melanoidin quantification and its influence on the color characteristics of brewing products. It is shown that the reaction conditions (100±2)°C, the processing time of 2 hours and a certain list of sugars and amino acids typical for brewing products are adequate to obtain linear dependencies for estimating the beer melanoidin content at 300 and 420 nm. The data on the total content of melanoidins in light beer in the range of 3.83-51.4 mg/dm3, and in dark beer – 6.82-145.94 mg/dm3 at the specified wavelengths are given. The authors found that the dependence between the color and the total beer melanoidin content is characterized by a correlation coefficient R = 0.624, which indicates the influence of other organic compounds of beer on the color intensity.

Modulatory Effect of Chlorogenic Acid and Coffee Extracts on Wnt/β-Catenin Pathway in Colorectal Cancer Cells

The Wnt/β-Catenin pathway alterations present in colorectal cancer (CRC) are of special interest in the development of new therapeutic strategies to impact carcinogenesis and the progression of CRC. In this context, different polyphenols present in natural products have been reported to have modulatory effects against the Wnt pathway in CRC. In this study, we evaluate the effect of two polyphenol-rich coffee extracts and chlorogenic acid (CGA) against SW480 and HT-29 CRC cells. This involved the use of MTT and SRB techniques for cell viability; wound healing and invasion assay for the evaluation of the migration and invasion process; T cell factor (TCF) reporter plasmid for the evaluation of transciption factor (TCF) transcriptional activity; polymerase chain reaction (PCR) of target genes and confocal fluorescence microscopy for β-Catenin and E-Cadherin protein fluorescence levels; and subcellular localization. Our results showed a potential modulatory effect of the Wnt pathway on CRC cells, and we observed a reduction in the transcriptional activity of β-catenin. All the results were prominent in SW480 cells, where the Wnt pathway deregulation has more relevance and implies a constitutive activation of the signaling pathway. These results establish a starting point for the discovery of a mechanism of action associated with these effects and corroborate the anticancer potential of polyphenols present in coffee, which could be explored as chemopreventive molecules or as adjunctive therapy in CRC.

Can coffee silverskin be a useful tool to fight metabolic syndrome?

Coffee is one of the most consumed products in the world, and its by-products are mainly discarded as waste. In order to solve this problem and in the context of a sustainable industrial attitude, coffee by-products have been studied concerning their chemical and nutritional features for a potential application in foodstuffs or dietary supplements. Under this perspective, coffee silverskin, the main by-product of coffee roasting, stands out as a noteworthy source of nutrients and remarkable bioactive compounds, such as chlorogenic acids, caffeine, and melanoidins, among others. Such compounds have been demonstrating beneficial health properties in the context of metabolic disorders. This mini-review compiles and discusses the potential health benefits of coffee silverskin and its main bioactive components on metabolic syndrome, highlighting the main biochemical mechanisms involved, namely their effects upon intestinal sugar uptake, glucose and lipids metabolism, oxidative stress, and gut microbiota. Even though additional research on this coffee by-product is needed, silverskin can be highlighted as an interesting source of compounds that could be used in the prevention or co-treatment of metabolic syndrome. Simultaneously, the valorization of this by-product also responds to the sustainability and circular economy needs of the coffee chain.

Melanoidins present in traditional fermented foods and beverages

Traditional fermented foods and beverages (TFFB) are an important dietary component consumed in large quantities worldwide. Currently, much attention has been focused on the health benefits of TFFB. Melanoidins, a class of bioactive substance produced in the final stage of the Maillard reaction, not only have a significant impact on sensory properties of TFFB but also contribute to the health effects. Melanoidins formed in the fermentation system with a long reaction time at low temperature could be different from those obtained from high-temperature, short-duration roasted systems due to the multiple formative stages and involvement of microorganisms and enzymes. In this paper, the current state of knowledge regarding the formation, distribution, extraction and purification, physicochemical properties, structure characteristics, and biological activities of TFFB melanoidins are comprehensively reviewed, with predominant focus on TFFB that are typically brown like douchi, miso, cheonggukjang, soy sauce, huangjiu (Chinese rice wine), beer, vinegar, and sweet wine. The current challenges and prospective recommendations for the research of melanoidins in fermented systems are also presented. In future, people should pay more attention to the basic research on TFFB melanoidins, especially purification methods and formation mechanisms, further substantiation of health properties of TFFB melanoidins in vivo, and development of specific melanoidins to fulfill technological, productive, or health needs of consumers.

Effect of Moderate Consumption of Different Phenolic-Content Beers on the Human Gut Microbiota Composition: A Randomized Crossover Trial

The moderate consumption of beer has been associated with positive effects on health, and these benefits are driven, in part, by the antioxidant properties of phenolic compounds found in this beverage. However, the potential impact of beer polyphenols on the human gut microbiome and their consequences are yet to be elucidated. In this study, our aim was to evaluate the effect of three different phenolic-content beers on the gut microbiome and the potential role of the induced shifts in the antioxidant capacity of beer polyphenols. In total, 20 subjects (10 healthy volunteers and 10 individuals with metabolic syndrome) were randomly assigned in a crossover design to consume each of the different beers (alcohol-free, lager or dark beer) during a 2-week intervention. Significant changes in the relative abundance of Streptococcaceae and Streptococcus were found after beer consumption. An increased abundance of Streptococcaceae and Streptococcus was observed after the consumption of dark beer, with no detected differences between baseline and alcohol-free/lager beer intervention. Moreover, some of the detected differences appeared to be related to the metabolic status. Finally, a decrease in porphyrin metabolism and heme biosynthesis was found after the intervention, especially after the consumption of dark beer. These results show that the antioxidant capacity of beer polyphenols may induce positive shifts in gut microbiota composition, and some of the observed changes may also boost the antioxidant capacity of these compounds.

Antimicrobial properties and volatile profile of bread and biscuits melanoidins

This work gives novel information about the antimicrobial effect and volatiles of melanoidins isolated from Maria biscuit, common and soft bread. Melanoidins were isolated from scraped and sieved crusts (1 mm), after gluten digestion, 10 kDa ultrafiltration, and diafiltration. Finally, they were freeze-dried. Headspace solid-phase dynamic extraction coupled with a gas chromatograph with a mass spectrometer was used to determine the volatile profiles. The antimicrobial effect was evaluated against isolated strains of the most relevant food spoilage and pathogen microorganisms, together with some molds and yeasts. Melanoidins from common bread exhibited the most extensive antimicrobial activities and showed the most composite volatile profile. No undesirable compounds, such as furfural and 5-hydroxy-methyl-furfural, were found in any of the melanoidins studied. The obtained data pointed out that bakery melanoidins can exert effective food technological properties as natural antimicrobials that can improve shelf-life and security of foodstuffs, together with a possible contribution to food aroma.

Dissecting grilled red and white meat flavor: Its characteristics, production mechanisms, influencing factors and chemical hazards

Meat flavor is composed of a complex mixture of volatile compounds developed as a result of heat driven multi-directional reactions. Typical reactions include Maillard reaction, lipid oxidation, as well as nitrogenous compounds degradation. Such complex flavor is characterized by a rich variety of volatile species, and to strongly influence consumer's preference. The objective of this review is to holistically dissect the flavor characteristic for cooked meat products with special emphasis on grilling and the factors that affect their production to ensure best quality and or safety levels. The review also highlights different analytical techniques used for the detection of flavor compounds in grilled meat. This comprehensive literature research critically analyze grilled flavor derived from heat mediated reactions, with a special emphasis on key flavors or hazard chemicals and their production mechanism. The various influencing factors i.e., grilling temperature, meat, food components, animal ante-mortem factors and food additives are summarized.

Treatment technologies for bakers' yeast production wastewater

Researchers in recent years have utilized a broad spectrum of treatment technologies in treating bakers' yeast production wastewater. This paper aims to review the treatment technologies for the wastewater, compare the process technologies, discuss recent innovations, and propose future perspectives in the research area. The review observed that nanofiltration was the most effective membrane process for the treatment of the effluent (at >95% pollutant rejection). Other separation processes like adsorption and distillation had technical challenges of desorption, a poor fit for high pollutant load and cost limitations. Chemical treatment processes have varying levels of success but they are expensive and produce toxic sludge. Sludge production would be a hurdle when product recovery and reuse are targeted. It is difficult to make an outright choice of the best process for treating the effluent because each has its merits and demerits and an appropriate choice can be made when all factors are duly considered. The process intensification of the industrial-scale production of the bakers' yeast process will be a very direct approach, where the process optimisation, zero effluent discharge, and enhanced recovery of value-added product from the waste streams are important approaches that need to be taken into account.

Characterization of Antioxidant Peptides from Thai Traditional Semi-Dried Fermented Catfish

Herein, the antioxidant peptides from a Thai traditional semi-dried fermented farmed hybrid catfish (Clarias macrocephalus × Clarias gariepinus) catfish, Pla Duk Ra, were characterized. After extraction and deproteinization, Pla Duk Ra crude peptide extract (CPE) was fractioned using 2 connected Hitrap Sephadex-G25 columns, yielding two significant fractions, F1 with higher browning intensity (A420) and F2. CPE, F1, and F2 had different amino acid profiles, contents, and sequences evaluated by LC-MS/MS, which could be responsible for their antioxidant properties. F2 contained the highest numbers of hydrophobic amino acid (HBA) (47.45%) and aromatic amino acid (27.31%), followed by F1, and CPE. The peptides with 8–24 amino acid residues were detected in CPE and its fractions. In CPE, F1, and F2, there were 69, 68, and 85 peptides with varied HBA content, respectively. ARHSYGMLYCSCPPND (50% HBA), ALRKMGRK (37.5% HBA), and ANWMIPLM (87.5% HBA) were the most prevalent peptides found in CPE, F1, and F2. Overall, F2 was the most effective at inhibiting free radicals (DPPH● and ABTS●+) and reactive oxygen species (hydroxyl radical, singlet oxygen, and hydrogen peroxide), followed by F1 and CPE. The metal chelation of F1 was, however, superior to that of F2 and CPE. For the stability test, the effects of pH, heating temperature, and in vitro digestion on the DPPH● scavenging activity of F2 were investigated. The activity was boosted by lowering the pH and raising the heating temperature. In the gastrointestinal tract model system, however, roughly 50% of DPPH● scavenging activity reduced after digesting.

Barley Melanoidins: Key Dietary Compounds With Potential Health Benefits

This paper is a review of the potential health benefits of barley melanoidins. Food melanoidins are still rather understudied, despite their potential antioxidant, antimicrobial, and prebiotic properties. Free radicals are villainous substances in humans produced as metabolic byproducts and causing cancers and cardiovascular diseases, and the melanoidins alleviate the effects of these free radicals. Malt is produced from cereal grains such as barley, wheat, and maize, and barley is predominantly used in beer production. Beer (alcoholic and non-alcoholic) is a widely consumed beverage worldwide and a good source of dietary melanoidins, which enhance the beers' flavor, texture, and sensorial properties. Melanoidins, the final products of the Maillard reaction, are produced at different stages during the brewing process. Beer melanoidins protect the cells from oxidative damage of DNA. The high reducing capacity of melanoidins can induce hydroxyl radicals from H₂O₂ in the presence of ferric ion (Fe³⁺). Melanoidins inhibit lipid peroxidation during digestion due to their chelating metal property. However, lower digestibility of melanoidins leads to less availability to the organisms but is considered to function as dietary fiber that can be metabolized by the lower gut microbiota and possibly incur prebiotic properties. Melanoidins promote the growth of Lactobacilli and Bifidobacteria in the gastrointestinal tract, preventing the colonization of potential pathogens. Barley is already popular through beer production and increasingly as a functional food. Considering this economic and industrial importance, more research to explore the chemical properties of barley melanoidins and corresponding health benefits as barley is warranted.

A Decade of Research on Coffee as an Anticarcinogenic Beverage

Coffee consumption has been investigated as a protective factor against cancer. Coffee is a complex beverage that contains more than 1000 described phytochemicals, which are responsible for its pleasant taste, aroma, and health-promoting properties. Many of these compounds have a potential therapeutic effect due to their antioxidant, anti-inflammatory, antifibrotic, and anticancer properties. The roasting process affects the phytochemical content, and undesirable compounds may be formed. In recent years, there have been contradictory publications regarding the effect of coffee drinking and cancer. Therefore, this study is aimed at evaluating the association of coffee consumption with the development of cancer. In PubMed, until July 2021, the terms “Coffee and cancer” resulted in about 2150 publications, and almost 50% of them have been published in the last 10 years. In general, studies published in recent years have shown negative associations between coffee consumption and the risk or development of different types of cancer, including breast, prostate, oral, oral and pharyngeal, melanoma, skin and skin nonmelanoma, kidney, gastric, colorectal, endometrial, liver, leukemic and hepatocellular carcinoma, brain, and thyroid cancer, among others. In contrast, only a few publications demonstrated a double association between coffee consumption and bladder, pancreatic, and lung cancer. In this review, we summarize the in vitro and in vivo studies that accumulate epidemiological evidence showing a consistent inverse association between coffee consumption and cancer.

Dissecting dietary melanoidins: formation mechanisms, gut interactions and functional properties

Dietary melanoidins are late stage Maillard reaction products (MRPs), browning colorants and predominantly high molecular weight (HMW) chemicals. They originate through polycondensation reactions of reducing sugars and proteins or amino acids upon thermal processing. Their presence in several daily food and beverages (i.e. coffee, beer, honey, bakery products, chocolate, grilled meat) contribute to food sensory characters (i.e. color, aroma, and flavor). Additionally, melanoidins exhibit many biological attributes (i.e. antioxidant, anti-obesity, antibacterial activity and impact on gut microbiota as prebiotics). However, dissecting melanoidins specific biological and functional characteristics in relation to their metabolism and gut interaction with link to their chemical structures has yet to be reported in literature. For a better understanding of melanoidins benefits and flavor properties in processed foods, this review represents a state of the art comprehensive insight of its formation mechanism and chemistry in relation to their functionalities and health effects. Further, a compile of the factors affecting melanoidins production to optimize for the best flavor attributes while minimizing hazardous compounds is presented. This study presents the first analysis of melanoidins gut interaction in context to its different action mechanisms.

Antitumor Effects of Freeze-Dried Robusta Coffee (Coffea canephora) Extracts on Breast Cancer Cell Lines

Coffee consumption is believed to have chemopreventive and chemotherapeutic effects and to contribute to preventing the development and progression of cancer. However, there is still controversy around these claims. As indicated in our previous works, diet can influence the risk of breast cancer. Intake of coffee is hypothesized to reduce this risk, but current scientific evidence is not conclusive. This work is aimed at studying the effects of Robusta coffee bean extract on cell viability, proliferation, and apoptosis of different human cancers, especially breast cancer cell lines. To this end, cell viability was evaluated by Alamar Blue in 2D and 3D models, the cell cycle by PI, apoptosis by annexin V, mitochondrial morphology, and functionality by mitoTracker, and colony formation capacity by the clonogenic assay. Green and dark coffee extract significantly reduced viability in human breast, colorectal, brain, and bone cancer cells. Coffee anticancer activity was clearly evidenced in MDA-MB-231 (ER⁻) and MCF-7 (ER⁺) breast cancer cells but not in the normal breast cell line. In addition, coffee extract induces an increase S phase and a decrease G2/M population in breast cancer cells, affected the mitochondrial morphology, and triggered apoptosis. MDA-MB-231 breast cancer cells lost their clonogenic capacity after treatment. The antitumor activity was demonstrated in both 2D and 3D culture cell models.

The Relationship between the Browning Index, Total Phenolics, Color, and Antioxidant Activity of Polish-Originated Honey Samples

Honey is a source of sugars, amino acids/proteins, and polyphenols, which are the main substrates and reactants in the Maillard reaction. Several bioactive molecules are formed and sequestered to the brown polymeric melanoidins, resulting in a gain and loss of antioxidant function in honey. Therefore, the relationships between the browning index and total phenolic contents, color, and antioxidant activity of Polish-originated honeys, namely acacia, buckwheat, heather, linden, multiflorous, and rapeseed, obtained from three local beekeepers, were addressed in this study. The Total Phenolic Content data showed the following order: buckwheat > heather > acacia > multiflorous > linden > rapeseed. The buckwheat honey also had the highest ability to scavenge free radicals in the range of 207.1–289.3 and 40.9–52.3 µmol Trolox g⁻¹, provided by Antioxidant Compounds Water-soluble and Ferric Reducing Antioxidant Power assays, respectively. Furthermore, a higher degree of browning was observed in dark-colored honey, such as buckwheat (3.1) and heather (1.35 mAU), than in light ones. Moreover, L* and b* parameters had a greater value in the honey of multiflorous, linden, and rapeseed, and a* was higher in buckwheat and heather. The variables of browning and TPC, ACW, and FRAP were positively correlated with each other. It can be concluded that the browning index strongly contributed to parameters of honey appearance, bioactive compound content, and antioxidant activity.

Insights into the Thermo-Mechanical Treatment of Brewers' Spent Grain as a Potential Filler for Polymer Composites

This paper investigated the impact of twin-screw extrusion parameters on the properties of brewers’ spent grain. The chemical structure, antioxidant activity, particle size, and color properties, as well as the emission of volatile organic compounds during extrusion, were investigated. The main compounds detected in the air during modifications were terpenes and terpenoids, such as α-pinene, camphene, 3-carene, limonene, or terpinene. They could be considered as a potential threat to human health and the environment. Changes in the chemical structure, antioxidant activity, and color of materials after modification indicated the Maillard reactions during extrusion, which resulted in the generation of melanoidins, especially at higher temperatures. This should be considered an exciting feature of this treatment method because modified brewers’ spent grain may improve the thermooxidative stability of polymer materials. Moreover, the impact of the brewers’ spent grain particle size on color and browning index used to determine the melanoidins content was investigated. The presented results show that proper adjustment of extrusion parameters enables the preparation of brewers’ spent grain with the desired appearance and chemical properties, which could maximize the efficiency of the modification process.

Potential applications of by-products from the coffee industry in polymer technology - Current state and perspectives

Coffee is one of the most popular beverages in the world, and its popularity is continuously growing, which can be expressed by almost doubling production over the last three decades. Cultivation, processing, roasting, and brewing coffee are known for many years. These processes generate significant amounts of by-products since coffee bean stands for around 50% of the coffee cherry. Therefore, considering the current pro-ecological trends, it is essential to develop the utilization methods for the other 50% of the coffee cherry. Among the possibilities, much attention is drawn to polymer chemistry and technology. This industry branch may efficiently consume different types of lignocellulosic materials to use them as fillers for polymer composites or as intermediate sources of particular chemical compounds. Moreover, due to their chemical composition, coffee industry by-products may be used as additives modifying the oxidation resistance, antimicrobial, or antifungal properties of polymeric materials. These issues should be considered especially important in the case of biodegradable polymers, whose popularity is growing over the last years. This paper summarizes the literature reports related to the generation and composition of the coffee industry by-products, as well as the attempts of their incorporation into polymer technology. Moreover, potential directions of research based on the possibilities offered by the coffee industry by-products are presented.

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).

On the Potential Role of Dietary Lysine as a Contributing Factor in Development of Liver Abscesses in Cattle

Liver abscessation is an important metabolic disorder that commonly afflicts cattle consuming cereal-based, high-concentrate diets. Economic ramifications of liver abscessation are substantial, and include liver condemnation, decreased body weight gain, poorer efficiency of feed utilization, reduced carcass yield, and impairments in operational efficiency of commercial abattoirs. The etiological agent most commonly associated with liver abscesses is Fusobacterium necrophorum, which is an anaerobic, Gram-negative, nonmotile, nonsporulating, and rod-shaped (pleomorphic) bacterium. Fusobacterium necrophorum is one of the major proteolytic species of bacteria in the rumen, and it is believed to have a major role in degradation of dietary lysine. Herein we describe interactions between lysine and F. necrophorum, and the potential role of dietary lysine as an enabling factor in the development of liver abscesses in cattle.

Physicochemical characteristics and antiproliferative and antioxidant activities of Moroccan Zantaz honey rich in methyl syringate

Zantaz honey is a monofloral variety produced from the melliferous plant Bupleurum spinosum (Apiaceae), a shrub that grows mainly in the Atlas Moroccan Mountains. Determination of the polyphenol composition revealed that methyl syringate accounts for more than 50% of total polyphenols, which represents a very useful parameter for the characterization of this monofloral honey. Epicatechin, syringic acid and catechin are also abundant. Caco-2 and THP-1 cells were used for determination of antioxidant and antiproliferative activities in Zantaz honey, respectively. All six commercial samples that were used for these studies exhibited antioxidant activity and inhibited cell proliferation. Interestingly, these activities had a positive correlation mainly with the content in methyl syringate and gallic acid. The recognition of health promoting activities in Zantaz honey should increase its commercial value, which would have a positive economic impact on the poor rural communities of Morocco where it is produced.

Maillard Mimetic Food-Grade Synthesis of N-(β-d-Deoxyfructos-1-yl)-l-glutamic Acid and N-(β-d-Deoxyfructos-1-yl)-β-alanyl-l-histidine by a Combination of Lyophilization and Thermal Treatment

A typical glycoconjugate of glutamic acid, namely, N-(β-d-deoxyfructos-1-yl)-l-glutamic acid, was successfully synthesized as the primary isomer in a yield of 96.08% using a food-grade preparation method, and its chemical structure was clearly demonstrated by mass spectrometry and 1D/2D NMR. The reaction kinetics of glucose and glutamic acid were systematically studied to investigate the effect of lyophilization and thermal treatment on the conversion of reactants to their corresponding Amadori rearrangement product (ARP). Interestingly, besides the initial pH value, temperature, and heating time, the initial concentration of glutamic acid also influenced the final yield because intramolecular dehydration occurred at the same time, competing with the Maillard reaction and degrading reaction. Moreover, a similar Amadori compound of carnosine was also prepared in a yield of about 66.38% and the yield could be further improved to 95% after condition optimization. One major isomer of the corresponding ARP of the peptide was confirmed to be N-(β-d-deoxyfructos-1-yl)-β-alanyl-l-histidine by structure characterization, indicating that this is a good method to prepare the N-(β-d-deoxyfructos-1-yl)-amino acid/peptide.

Fermentation of texturized vegetable proteins extruded at different moisture contents: effect on physicochemical, structural, and microbial properties

To investigate the effect of fermentation on texturized vegetable protein (TVP), TVPs extruded at 40 and 50% feed moisture contents (MC) were fermented using Bacillus subtilis at 37 °C. Physicochemical, structural and microbial properties of TVPs were determined at 0, 12, 24, 36, 48, and 60 h after fermentation. Integrity index of fermented TVPs did not change significantly until 24-36 h after fermentation. Springiness and cohesiveness remained stable after fermentation in all samples. Significant total color change was observed during fermentation. The pH values dropped initially and rose again with a coincident increase in nitrogen solubility index and viable cell count of B. subtilis. During fermentation, TVP extruded at 50% MC maintained higher chewiness, hardness, integrity index, and layered structure than that extruded at 40% MC. The study demonstrated that fermenting the TVP extruded at 50% MC has potential to produce a new type of TVP based B. subtilis fermented food.

Physiological relevance of food antioxidants

Dietary antioxidants are associated with prevention of oxidative stress related chronic diseases including certain types of cancer, cardiovascular diseases, diabetes, and neurodegenerative diseases. In recent years, there has been a growing interest in extending the knowledge on their physiological effects in human body. There are numbers of epidemiological, clinical, meta-analysis, and in vitro studies to explain formation mechanisms of each chronic diseases as well as the potential effects of dietary antioxidants on these diseases and gut health. Comprehensive studies for food antioxidants' journey from dietary intake to target tissues/organs deserve a serious consideration to have a clear understanding on the physiological effects of dietary antioxidants. Therefore, absorption and metabolism of dietary antioxidants, and the factors affecting their absorption, such as solubility of antioxidants, food matrix, and interaction between antioxidants have been evaluated in several research articles. This chapter provides an overview about potential health effects of dietary antioxidants considering with their absorption and metabolism in human body.

Phenols and Melanoidins as Natural Antioxidants in Beer. Structure, Reactivity and Antioxidant Activity

Beer is one of the most consumed drinks around the world, containing a variety of compounds that offer both appreciated sensorial characteristics and health advantages. Important healthy compounds in beer are those with antioxidant properties that attenuate the content of free radicals produced as by-products in the human metabolism, exerting an appreciable effect against cancers or cardiovascular diseases. This work details a study of antioxidant compounds present in beer, focusing on the two main groups: phenols (including polyphenolic forms) and melanoidins, formed specifically during brewing as Maillard products. The fundaments of the most important methods to evaluate beer antioxidant activity, the main antioxidant compounds present in beer-especially those with healthy properties-and the new trends to increase beer antioxidant activity are also discussed.

Antioxidant Activity and Phenolic Profile of Selected Organic and Conventional Honeys from Poland

Honey is a natural food product hypothesized to have significant health-beneficial value. The results of recent studies indicate that the biological activity of honey can also be ascribed to phenolic compounds and their antioxidant activity. The aims of this study were: To determine the phenolic profiles of several varieties of Polish honey and their correlation with various factors influencing the quality of honey, plus to verify the impact of production method (organic/conventional) and the pollen content on these profiles. In total, 11 organic and 11 conventional honey samples from Poland were investigated. The botanical origin of the samples was identified through melissopalynological analysis, whereas individual phenolic compounds were determined by the LC/MS analysis. The Folin-Ciocalteau assay was used for the determination of the total phenolic content (TPC). Moreover, the CIE L*a*b* color values were measured and matched with the above-mentioned parameters. The results of the study contribute to the discussion on the health benefits of organic farming. It was found that chrysin may act as a potential indicator compound. The study confirms the existence of the link between TPC and color, and it shows that there is a correlation between pinocembrin and galangin, two compounds that are reported to ameliorate insulin resistance.

High Hydrostatic Pressure-Assisted Extraction of High-Molecular-Weight Melanoidins from Black Garlic: Composition, Structure, and Bioactive Properties

Melanoidin is one of the most important ingredients in black garlic due to the high nutritional values and biological functions. High hydrostatic pressures from 200 to 500 MPa were employed to extract the melanoidins from black garlic for improving the extraction efficiency and enhancing the activities. The results indicated that total phenolics, flavonoids, and sugar yields were all increased when pressure was applied and the antioxidant and overall reducing power was maximized. The bioactive properties of protein tyrosine phosphatase 1B, angiotensin-converting enzyme, and trypsin inhibitory activities were also enhanced compared with the control. Moreover, FT-IR spectroscopy indicated high pressure altered the melanoidin structures to different degrees. It was found that an application of 300 MPa for 5 min was the optimal treatment protocol under all operating conditions.

Nutritional, Functional and Sensory Properties of Ready-To-Eat Chia and Quinoa Mix Enriched Low Amylose Rice Based Porridge Mixes

Ready-to-eat porridges are prepared from cereal flours. Pregelatinization of the starch component results in high hygroscopicity of porridge flours resulting in easy reconstitution. Chia and quinoa seeds are popular due to their health-promoting nutritional composition and functionality. In this study, 10%, 15 % and 20% of a pregelatinized low amylose ready-to-eat rice flour were substituted with a 1:1 mixture of chia and quinoa seed flours. Analysis of the significant difference between all the results was carried out by Duncan’s multiple range test at a significance level of 0.05. Substitution significantly enhanced levels of proteins, dietary fibres, iron, calcium, potassium, sodium and zinc. Palmitic, stearic and oleic acids were proportionately higher than lesser significant changes in linoleic and alpha-linolenic acid. Although thermal destruction caused a marked reduction of total phenolic and flavonoid contents, the relative rise in ferric and cupric ion reducing the antioxidant potentials suggested the probable formation of Maillard compounds with radical scavenging properties. Chia seed mucilage was found to play a critical role in thickness and viscosity development in the optimally reconstituted porridges. Supporting results were also obtained from the texture analysis of the porridges. However, the mucilage was observed to be sensitive to high cooking temperature resulting in lower cold paste viscosity in the rapid viscosity analysis study. The roasted aroma in porridges was more acknowledged. Substitution level of 20% gave an overall sensory score below the set acceptance level. Hence, porridge mixes prepared from the rice flour substituted up to 15% with the flour mix was sensorily acceptable, rich in macro and micronutrients and can serve as a therapeutic diet for infants, old-aged and patients with poor digestive systems.

Cocoa Bean Proteins-Characterization, Changes and Modifications due to Ripening and Post-Harvest Processing

The protein fractions of cocoa have been implicated influencing both the bioactive potential and sensory properties of cocoa and cocoa products. The objective of the present review is to show the impact of different stages of cultivation and processing with regard to the changes induced in the protein fractions. Special focus has been laid on the major seed storage proteins throughout the different stages of processing. The study starts with classical introduction of the extraction and the characterization methods used, while addressing classification approaches of cocoa proteins evolved during the timeline. The changes in protein composition during ripening and maturation of cocoa seeds, together with the possible modifications during the post-harvest processing (fermentation, drying, and roasting), have been documented. Finally, the bioactive potential arising directly or indirectly from cocoa proteins has been elucidated. The “state of the art” suggests that exploration of other potentially bioactive components in cocoa needs to be undertaken, while considering the complexity of reaction products occurring during the roasting phase of the post-harvest processing. Finally, the utilization of partially processed cocoa beans (e.g., fermented, conciliatory thermal treatment) can be recommended, providing a large reservoir of bioactive potentials arising from the protein components that could be instrumented in functionalizing foods.

Coffee variety, origin and extraction procedure: Implications for coffee beneficial effects on human health

We set up an efficient protocol for the rapid analysis of NMR spectra of green and roasted coffee extracts, enabling the automatic identification and quantification of metabolites in approximately two minutes per spectrum. This method allowed for the metabolic profiling and the subsequent evaluation of the content of bioactive compounds and antioxidant activity of coffee samples, depending on their species (Arabica and Robusta), geographical origin and extraction procedure (hydroalcoholic, espresso and moka). The hydroalcoholic extraction is the most efficient method in terms of yields of low molecular weight compounds (in particular chlorogenic acids), while moka extraction provides the highest amounts of melanoidins. Moreover, that the ratio between health-giving compounds (chlorogenic acids, trigonelline and choline) and caffeine is higher in Arabica coffees. The data collected provide useful insights for the selection of coffee raw material to be used in the preparation of coffee-based dietary supplements, nutraceuticals and functional beverages.