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The objective of this study was to identify bioactive oligosaccharides and peptides in the cooking water of chickpeas and common beans, known as aquafaba. The oligosaccharides stachyose, raffinose and verbascose were quantified by high-performance anion-exchange chromatography; 78 and 67 additional oligosaccharides were identified in chickpea and common bean aquafaba, respectively, by LC-MS/MS. Chickpea aquafaba uniquely harbored ciceritol and other methyl-inositol-containing oligosaccharides. In prebiotic growth assays, chickpea aquafaba oligosaccharides were differentially utilized, promoting growth of Limosilactobacillus reuteri DSM 20016 and Bifidobacterium longum subsp. infantis ATCC 15697, but not Lacticaseibacillus rhamnosus GG. Dimethyl labeling, along with LC-MS/MS, effectively differentiated α- and γ-glutamyl peptides, revealing the presence of several γ-glutamyl peptides known to possess kokumi and anti-inflammatory activities, including γ-Glu-Phe and γ-Glu-Tyr in chickpeas aquafaba and γ-Glu-S-methyl-Cys and γ-Glu-Leu in beans aquafaba. This work uncovered unique bioactive peptides and oligosaccharides in aquafaba, helping promote its valorization, food system sustainability, and future health-promoting claims., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Oligosaccharides are known for several bioactivities on health, however, in sensitive individuals, can cause intestinal discomfort. This study aimed to investigate the oligosaccharide profiles in selected plant-based food products. A quantification method based on high-performance anion-exchange chromatography-pulsed amperometric detection was developed, validated, and used to measure major oligosaccharides. Additional low-abundant oligosaccharides and glycosides were characterized by liquid chromatography-tandem mass spectrometry and glycosidases. The summed concentration of raffinose, stachyose, and verbascose ranged from 0.12-0.19 mg/g in almond milk, 3.6-6.4 mg/g in soy milk, and 74-77 and 4.8-57 mg/g in defatted and full-fat soy four. Over 80 different oligosaccharides were characterized. Novel compounds, 2,3-butanediol glycosides, were identified in almond milk. Low-abundant oligosaccharides represented 25 %, 6 %, and 10 % of total OS in almond milk, soy milk, and soy flour, respectively. The data here are useful to estimate oligosaccharide consumption from dietary intake and facilitate further studies on their bioactivity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Identification of bioactive peptides is an increasingly important target for food chemists, particularly in consideration of the widespread application of proteolytic enzymes in food processing. Because the characterization of small peptides by LC-MS/MS is challenging, we optimized a dimethyl labeling technique to facilitate small peptide identification, using almond proteins as a model. The method was validated by comparing the MS/MS spectra of standards and almond-derived peptides in their nonderivatized and derivatized forms. Signal enhancement of a 1 ions was proved to effectively aid in the full-length sequencing of small peptides. We further validated this method using two industrially-relevant protein-rich extracts from almond flour: 1737 medium-sized peptides (5-39 amino acids) and 843 small peptides (2-4 amino acids) were identified. The use of an online bioactive peptide database, complemented by the existing literature, allowed the discovery of 208 small bioactive peptides, whereas for medium-sized peptides, only one was reported being bioactive., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Human milk is a dynamic protein-protease system that delivers bioactive peptides to infants. The pH of milk changes from the mother's mammary gland to the infant's digestive tract. Although the release of human milk peptides has been studied during in vivo or in vitro digestion, these models did not explicitly vary nor observe the effect of pH. The objective of this research was to determine the effect of pH on the proteolysis of human milk. Using high-resolution accurate-mass Orbitrap mass spectrometry, profiles of endogenous human milk peptides before and after incubation at various pH levels have been mapped. Over 5000 peptides were identified. Comparative analyses classified 74 peptides that were consistently found independent of pH alterations, and 8 peptides that were released only at pH 4 or 5 (typical infant gastric pH). Results documented that the proteolysis of milk proteins, particularly β-casein, polymeric immunoglobulin receptor, and α-lactalbumin, is pH-dependent., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Scope: The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins., Methods and Results: Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species., Conclusion: The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Anthocyanin degradation has been proposed as one of the primary causes for reduced colour and quality in red wine grapes grown in a warm climate. To study anthocyanin degradation we infused berries with L-phenyl-(13)C₆-alanine and then tracked the fate of the anthocyanins comparing normal (25 °C) and warm (45 °C) temperature conditions. An untargeted metabolomics approach was aided by filtering the MS data using software algorithms to extract all M and M+6 isotopic peak pairs, allowing the analysis to focus solely on the metabolites of phenylalanine. A paired-comparison t-test was performed over the 8 biological replicates revealing 13 metabolites that were statistically different between 25 °C and 45 °C treatments. Most of these features had lower abundances in 45 °C samples, confirming that 45 °C treatment caused anthocyanin degradation. In addition, resveratrol was significantly reduced following heat treatment. However, 5 metabolites increased following the 45 °C treatment. These unidentified metabolites are therefore suspects for anthocyanin degradation products., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Hazelnut skins are a good example of agricultural by-product with the potential to become a valuable source of functional ingredients. In this work, the fibre from hazelnut skins was extracted by using water and alkali solution and characterised by a suite of analytical tools (MALDI-FTICR, nano LC-Chip-Q-ToF and gas chromatography). Over thirty complex free oligosaccharides, composed mainly of galacturonic acid and N-acetylgalactosamine, were characterised for the first time in the present study. Their concentration ranged between 16 and 34mg per g of extract. The oligosaccharides isolated from this agricultural by-product are mainly hexose oligosaccharides (potentially galacto-oligosaccharides,) and xyloglucans. The identified composition could justify the bioactive activity of the extracts, namely prebiotic activity, previously demonstrated., (Copyright © 2013 Elsevier Ltd. All rights reserved.)