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Alternative sources of edible proteins are required to feed the world's growing population, such as Moringa oleifera leaves, a protein source with a balanced amino acid composition. Since Moringa leaf proteins is a novel food in the EU and UK, an assessment of their potential allergenicity of is required. Proteins from Moringa leaf powder were characterised using traditional proteomic approaches. The proteins identified were evaluated for their allergenic potential using in-silico tools. The main proteins identified belonged to photosynthetic and metabolic pathways. In-silico analysis of the leaf proteome identified moritides as potential allergens by homology with a latex allergen implicated in fruit-latex syndrome. This analysis also identified a nsLTP, a major panallergen in food. The presence of these putative allergens was confirmed by de-novo sequencing. Our study allowed identification of putative allergens, Morintides and nsLTP. Further in-vitro and in-vivo investigations are required to confirm their allergenic potential. Proteins from Moringa leaf powder were characterised using traditional proteomic approaches. The proteins identified were evaluated for their allergenic potential using in-silico tools. The main proteins identified belonged to photosynthetic and metabolic pathways. In-silico analysis of the leaf proteome identified moritides as potential allergens by homology with a latex allergen implicated in fruit-latex syndrome. This analysis also identified a nsLTP, a major panallergen in food. The presence of these putative allergens was confirmed by de-novo sequencing. Our study allowed identification of putative allergens, Morintides and nsLTP. Further in-vitro and in-vivo investigations are required to confirm their allergenic potential.

Heat-stable peptidases released in refrigerated raw milk by psychrotrophic bacteria are responsible for UHT milk gelation. K-casein-derived caseinomacropeptides, identified by mass spectrometry, were constantly detected in gelled milk by capillary electrophoresis. Strains of Pseudomonas fluorescens, Ps. poae and Chryseobacterium joostei, selected among aprX-positive strains from raw milk, were incubated in milk up to 6 days at 4 degrees C before sterilization (98 degrees C/4 min). Samples were then stored at 25 or 40 degrees C, visually observed for gelation, and analysed for presence of caseinomacropeptides throughout 90 days of storage. Depending on cold pre-incubation time, caseinomacropeptides accumulated well before gelation onset in milk stored at 25 degrees C. Caseinomacropeptides were successively degraded, especially in milk stored at 40 degrees C, due to extensive proteolysis, and an abundant sediment developed instead of a gel. The caseinomacropeptides are here presented as an early indicator of UHT milk gelation and a mechanism explaining this phenomenon is proposed.

The aim of this study was to evaluate the dynamics of proteolysis during dough fermentation started with different lactic acid bacteria species, through the identification of intermediate and small-sized peptides generated during fermentation. Single-strain cultures of Levilactobacillus brevis, Fructilactobacillus sanfranciscensis, Companilactobacillus alimentarius, and Leuconostoc pseudomesenteroides were assayed as sourdough starters. Assays were carried out at lab-scale for 48 h of fermentation, using both unstarted and yeast-leavened dough as controls. Physicochemical and microbiological analyses were combined with peptidomic and proteomic profiling, identifying several hundreds of peptides mainly released from the water-soluble wheat proteins, including β-amylase, triticin, and serpins. Both α- and γ-gliadins were hydrolyzed, though only at the N-terminal domain, while the central protein region – encrypting celiac disease epitopes– remained unaffected. The bacterial-mediated consumption of sugars and the concomitant hydrolysis of starch degrading β-amylase could underlie improved digestibility and several nutritionally beneficial effects of sourdough baked products.

IgE-mediated allergy to soybean may be connected to an incomplete protein digestion causing an inappropriate immune response in the gut. The aim of this study was to gain insight on the digestibility and immunoreactivity of β-conglycinin and its deglycosylated form. To achieve this goal both proteins were digested mimicking gastrointestinal physiological conditions. Digests were characterised by SDS-PAGE, MALDI-TOF-MS and immunological assays. Data on IgG binding western blot provided key information related to the composition of the digests indicating that whereas deglycosylated β-conglycinin was completely removed by gastrointestinal digestion, α and β subunits of β-conglycinin glycoprotein partially survive the process of digestion. Such differential digestive behaviour might be influenced by glycan moieties, at least to some extent, and should be an additional factor to be considered on its potential allergenicity. Results also support the existence of linear epitopes in the three subunits (α, α′, and β) of both protein forms. © 2011 Elsevier Ltd. All rights reserved., This work has been funded by ERDF-co-financed grant AGL2007-60007/ALI, CONSOLIDER Ingenio 2010 FUN-C-FOOD: CSD 2007-00063, ALIBIRD-CM-S0505/AGR-0153 and IT-2009- 0087 projects. Dr. M.A-B. thanks European Union COST-Action 927 for Short Term Scientific Mission and Danone Institute for her fellowship.

In this study, the protein and peptide fractions of two commercial Italian barley malt beers, made with different processes by the same producer, have been analysed with a combined immunochemical and mass spectrometry approach. The “gluten” content of beer samples, measured with the R5 monoclonal antibody, was below the caution limit proposed by the Codex Alimentarius for gluten-free foods. The proteomic approach allowed to identify a 17 kDa avenin-like protein partially homologous to hordeins, that was particularly abundant in foam, in addition to the already reported barley albumins (Z 4 -barley and ns-LTPs) and to minor amounts of yeast glycolytic enzymes. No intact hordeins were detected, although fragments derived from γ 3 - and B-hordein were present. In consideration of the many implications of the protein/peptide pattern, these data provide useful information to improve quality and safety of beer.

Molecular approaches by means of a combined use of mass spectrometric techniques can be important in order to open new possibilities in the differentiation and defense of typical products; in this study, a possible approach to the analysis of varietal volatile compounds and some precursors of a non-aromatic grape variety (Falanghina cv., Vitis vinifera L.) was traced through a combined use of techniques based on mass spectrometry (GC/MS, LC/ESI-MS, MALDI-TOF-MS). Dominant terpene compounds (limonene, cis-furanlinalool oxide, geraniol, 4-carene, myrcene, linalool, a-terpineol), terpene-derivatives (bornyl acetate, menthol), terpene glycosides (glucosides, arabinosylglucosides and rhamnosylglucosides of linalool and geraniol), and norisoprenoids (b-damascenone) were identified in grapes and monovarietal wines, overcoming the analytical difficulties deriving from the low concentration of these compounds strictly related to the variety. The potential release of varietal volatile compounds from the grapes was also explored by enzyme hydrolysis.

A growing interest in developing new strategies for preventing coeliac disease has motivated efforts to identify cereals with null or reduced toxicity. In the current study, we investigate the biological effects of ID331 Triticum monococcum gliadin-derived peptides in human Caco-2 intestinal epithelial cells. Triticum aestivum gliadin derived peptides were employed as a positive control. The effects on epithelial permeability, zonulin release, viability, and cytoskeleton reorganization were investigated. Our findings confirmed that ID331 gliadin did not enhance permeability and did not induce zonulin release, cytotoxicity or cytoskeleton reorganization of Caco-2 cell monolayers. We also demonstrated that ID331 omega-gliadin and its derived peptide omega(105-123) exerted a protective action, mitigating the injury of Triticum aestivum gliadin on cell viability and cytoskeleton reorganization. These results may represent a new opportunity for the future development of innovative strategies to reduce gluten toxicity in the diet of patients with gluten intolerance. (C) 2016 Elsevier Ltd. All rights reserved.