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Waxy (WX) and high-amylose (HA) wheat flours have interesting functional and/or nutritional characteristics, but low technological properties compared to regular wheat. Here a set of three wheat lines, having different amylose content but sharing the same varietal background, were compared to shed light on the role of the amylose/amylopectin ratio on the protein conformational changes that lead to gluten formation. Despite the absence of differences in their protein profile, as also confirmed by thiolomic approaches, both WX and HA lines developed a weaker gluten than the control sample. The altered amylose/amylopectin ratio exerts a matrix effect establishing a competition for water with proteins, leading to a different protein structure and three-dimensional organization of the gluten network. These results add a piece to the understanding of the molecular aspects that oversee matrix effects on gluten formation in wheat, which description can be helpful for a rational optimization of the transformation process.

Aims To investigate the characteristics of two minority autochthonous LAB species, with particular regard to those properties that could be exploited in an improved cocoa fermentation process from a quality and safety point of view. Methods and Results Bacterial, yeast and mould strains characteristic of spontaneously fermented Dominican cocoa beans were isolated and identified by 16S or 26S rRNA gene sequencing. The potential of two autochthonous strains of LAB belonging to the species Lactiplantibacillus fabifermentans and Furfurilactibacillus rossiae were investigated. The two selected LAB strains were able to utilize glucose and fructose, produced mainly D-L lactic acid and had a good ability to resist to cocoa-related stress conditions such as low pH, high temperature and high osmotic pressure, as well as to grow in sterile cocoa pulp. The strains did not inhibit the growth of yeasts and acetic acid bacteria, that are essential to the cocoa fermentation process, and possessed a complex pool of peptidases especially active on hydrophobic amino acids. The strains also showed antifungal activity against mould species that can be found at the final stages of cocoa fermentation, as Aspergillus tamarii, A. nidulans, Lichtheimia ornata and Rhizomucor pusillus. Conclusions The tested strains are good candidates for the design of starter cultures for a controlled cocoa fermentation process. Significance and Impact of the Study This research showcases the potential of two alternative LAB species to the dominating Lactiplantibacillus plantarum and Limosilactibacillus fermentum as cocoa fermentation starters, with an interesting activity in improving the safety and quality of the process.

Thermal treatments are widely applied to gluten-free (GF) flours to change their functionality. Despite the interest in using pulses in GF formulations, the effects of thermal treatment at the molecular level and their relationship with dough rheology have not been fully addressed. Raw and heat-treated red lentils were tested for starch and protein features. Interactions with water were assessed by thermogravimetric analysis and water-holding capacity. Finally, mixing properties were investigated. The thermal treatment of red lentils induced a structural modification of both starch and proteins. In the case of starch, such changes consequently affected the kinetics of gelatinization. Flour treatment increased the temperature required for gelatinization, and led to an increased viscosity during both gelatinization and retrogradation. Regarding proteins, heat treatment promoted the formation of aggregates, mainly stabilized by hydrophobic interactions between (partially) unfolded proteins. Overall, the structural modifications of starch and proteins enhanced the hydration properties of the dough, resulting in increased consistency during mixing.

Climate change and shifting patterns in the consumer's demand represent major challenges for the agrifood chain. In the case of grain-based products, consumers would appreciate staple foods (pasta and bread) with traditional sensory features but without their nutritional drawbacks, such as the high glycemic index. Protein networks play a crucial role in defining the sensory characteristics in cereal-based products by forming both covalent and non-covalent interactions. Process-induced structural changes (and their kinetics) affect the organization of proteins in the network, resulting in macroscopic changes. However, other components in the matrix may affect a number of steps in the process, including competition for water at various steps of processing. A detailed knowledge of these effects is also pertinent to the production of food enriched with nutritionally relevant ingredients - including fiber, phenolics, and other bioactives - obtained from agrifood by-products. This work addresses the pattern of protein-protein interactions in isogenic bread wheat lines, that included a control line (WT), a waxy (i.e. no amylose) line (WX), and a high-amylose line (HA), along with a commercial bread wheat flour. Protein profiles were assessed by mono- and bi-dimensional electrophoresis. The chemical nature of protein-protein interactions was assessed by studying the sensitivity of the water-insoluble proteins to the sequential addition of salts, chaotropes, and disulfide reductants. Properties of hydrophobic patches on the protein surface were assessed by measuring binding of ANS (1,8 aniline naphthalene sulfonate) by front-face fluorescence. A "thiolomics" approach based on labeling of thiols with 5-(iodoacetamide) fluorescein (IAF) was used to assess the accessibility of protein thiols in the original materials and in protein fractions solubilized in suitable solvent systems. The protein patterns in the isogenic wheats were identical, but different from that in the commercial flour in both gluten components (monomeric gliadins and polymeric glutenins). In spite of the identical protein profile, the sensibility of the insoluble protein aggregates to both chaotropes and disulfide reductants in the isogenic samples increased in the order: WT<