Brazilian grape pomace was extracted in hot water, and a factorial experiment was used to evaluate polysaccharide recovery. The dependent variables were the temperature, particle size and solute:solvent ratio. Polysaccharide yields varied from 3% to 10%, and the highest sugar content was observed when extraction was carried out at 100 °C from finely sized particles (⩽249 μm) in a 1:12 solute:solvent ratio. The monosaccharide composition of extracts obtained from flours were, on average, Rha:Ara:Xyl:Man:Gal:Glc:GalA in a 3:32:2:13:11:20:19 M ratio, with varying Glc:GalA ratios. (13)C NMR and HSQC spectra confirmed the presence of pectic- and glucose-based polysaccharides in the extracts. Phenolic compounds were found after pomace extraction, and catechin, gallic acid and epicatechin were the principal compounds identified. The extracts also had ABTS radical scavenging capacity (from 8.00 to 46.60 mMol Trolox/100 g pomace). These findings indicate that these grape pomace flours are rich in antioxidant dietary fibre and have a potential use as food ingredients.

For many years, it was believed that only amino acids, dipeptides, and tripeptides could be absorbed and thus reach the bloodstream. Nowadays, the bioavailability of oligopeptides is also considered possible, leading to new research. This pilot study investigates the activity of brush border enzymes on undigested whey protein hydrolysate (WPH) and on simulated intestinal digested (ID) whey hydrolysate and the subsequent absorption of resultant peptides through the proximal jejunum of a 7-week old piglet setup in an Ussing chamber model. Amongst all samples taken, 884 oligopeptides were identified. The brush border peptidase activity was intense in the first 10 min of the experiment, producing several new peptides in the apical compartment. With respect to the ID substrate, 286 peptides were detected in the basolateral compartment after 120 min of enzyme activity, originating from β-lactoglobulin (60%) and β-casein (20%). Nevertheless, only 0.6 to 3.35% of any specific peptide could pass through the epithelial barrier and thus reach the basolateral compartment. This study demonstrates transepithelial jejunum absorption of whey oligopeptides in an ex vivo model. It also confirmed the proteolytic activity of brush border enzymes on these oligopeptides, giving birth to a myriad of new bioactive peptides available for absorption.

The high hydrostatic pressure (HHP) process has been studied for several applications in food technology and has been commercially implemented in several countries, mainly for non-thermal pasteurization and shelf-life extension of food products. HHP processing has been demonstrated to accelerate proteolytic hydrolysis at a specific combination of pressure and pressure-holding time for a given protein source and enzyme. The enzymatic hydrolysis of proteins is a well-known alternative to producing biologically active peptides, with antioxidant and antihypertensive capacity, from different food protein sources. However, some of these protein sources contain allergenic epitopes which are often not degraded by traditional hydrolysis. Moreover, the peptide profile and related biological activity of a hydrolysate depend on the protein source, the enzymes used, the parameters of the proteolysis process (pH, temperature, time of hydrolysis), and the use of other technologies such as HHP. The present review aims to provide an update on the use of HHP for improving enzymatic hydrolysis, with a particular focus on studies which evaluated hydrolysate antihypertensive and antioxidant capacity, as well as residual allergenicity. Overall, HHP has been shown to improve the biological properties of hydrolysates. While protein allergenicity can be reduced with traditional hydrolysis, HHP can further reduce the allergenicity. Compared with traditional hydrolysis methods, HHP-assisted protein hydrolysis offers a greater opportunity to add value to protein-rich products through conversion into high-end hydrolysate products with enhanced nutritional and functional properties.

There is an enormous demand to develop new sources of proteins, mainly to supply the growing plant-based food market worldwide, with the push for more sustainable and healthier products. The objective of this study was to evaluate the composition and the nutritional properties of commercial soybean, pea, and fava bean protein ingredients and compare them with an in-house ingredient (flour and protein concentrate), obtained from the main Brazilian cultivar of common bean (Phaseolus vulgaris, Pinto bean). The protein content of the common bean concentrate (79.75%) was as high as other commercial proteins isolated from the pea and higher than the others concentrates. All the ingredients presented the minimum amounts of indispensable amino acids as required by FAO and all ingredients were rich in lysine and leucine, with the highest amounts found for pea (78.06 mg/g) and common bean (86.70 mg/g) concentrates. A diverse mineral composition was reported for all the ingredients and the common bean concentrate presented the highest iron content (342.6 mg/kg). In terms of antinutritional factors, the common bean flour and concentrate showed the highest values for trypsin inhibitor (18 and 27 TIU/mg, respectively) but the lowest ones for phytic acid (9 and 2 mg/g, respectively) compared to the other ingredients. Low amounts of oligosaccharides were found in most of the samples. All proteins from the ingredients were highly digested when evaluated in vitro, but phaseolins fraction protein from common bean samples remained partially undigested. Despite compositional differences between ingredients, all samples should be suitable as protein sources for plant-based food innovation.

Whey is well-known for the functional and bioactive properties of its proteins and peptides, which are of great interest to food and nutraceutical industries. The aim of this study was to investigate the effect of four different commercial proteases (Novo ProD® (NPD), Alcalase® (ALC), Pancreas Trypsin® (TRY), and Flavourzyme® (FLA)) in the generation of hydrolysates with emulsifying and antioxidant activities. Hydrolysis processes were carried out for 5 h, reaching maximum degrees of 18.5, 15.5, 9.2, and 8.7% for NPD, ALC, TRY, and FLA, respectively. All tested enzymes generated very diverse, but conservative peptide profiles when comparing the treatments along the time, with the main enzymatic actions up to 120 min-reaction. An increase in the in vitro antioxidant activity was found for all treatments, achieving 46%, 40%, 40% and 22% for ALC, TRY, NDP and FLA, respectively. TRY hydrolysate maintained or slightly increased its emulsifying capacity along the time, however, a decrease in emulsifying capacity was found for ALC and NPD hydrolysates when compared to the non-hydrolyzed whey protein concentrate (WPC). All tested enzymes generated hydrolysates with enhanced antioxidant and/or emulsifying activities, which may be used as food ingredients and the choice of the enzyme will depend on the need.