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The nutritional value and digestibility of leaf proteins is still a major issue. Therefore, the goal of this work was to optimize the production of a protein concentrate (PC) from Moringa Oleifera defatted leaves (MODL) by enzymatic extraction using Viscozyme L and evaluate its nutritional quality and digestibility. Protein extraction conditions were screened using a factorial design. Enzyme/Substrate ratio and pH had no significant effect, whereas, the significant variables, temperature (°C), enzyme concentration and incubation time (h) were optimized by central composite design (CCD). PC contained 55.7% of proteins with a balanced amino acid profile when compared with MODL and higher content of essential amino acids (EAAs) (488.6-402.9 mg/g of protein respectively). Improvement on protein digestibility was observed for MODL compared to PC (64.75-99.86% respectively) and higher protein digestibility corrected amino acid score (PDCAAS) (62.10-91.41% respectively). PC meets FAO protein quality expectations., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The effect of gaseous ozone (500-1000 ppm) treatment on the protein, amino acid, and fatty acid profiles, mineral content, and the microstructure of the chickpea grains were evaluated. Though protein content was not altered significantly, SDS PAGE profiling exhibited minor modifications in the protein bands of the treated chickpea. The essential amino acids (EAA) and total amino acids (TAA) slightly decreased, ratio of EAA to TAA increased, while the calculated protein efficiency ratio decreased. Significant decrease in the SH content and non-significant increase in SS content was observed at higher doses of ozone. The overall saturated and unsaturated fatty acids (%) were in the range of 13.05-13.49 and 86.51-87.61, respectively. The minerals were stable and the HCl extractability decreased in the ozonated samples. There was some minor degradation of intracellular cell wall and distribution of starch and protein bodies in the ozonated sample., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Pumpkin seeds are rich source of nutritionally well-balanced proteins. The biochemical, nutritional, and functional properties of the protein isolate (PPI) and protein fractions from pumpkin seed were evaluated. Extraction method for PPI was optimized by varying NaCl (0, 0.5, 1 M) and flour-to-solution ratio (1:5, 1:10, 1:25), at pH 9.0. Proteins were extracted by Osborne procedure and the alkali fraction (AF, 45.82%) was found to be the predominant fraction. SDS-PAGE profile of PPI revealed major bands ranging from 50 to 7 kDa. AF contained all the essential amino acids (EAA) except lysine and threonine, as required by pre-school children (FAO/WHO). PPI and AF showed better protein efficiency ratio and EAA/TAA (total) %, indicating the presence of good quality proteins. Functional properties were found to be comparable with soybean protein isolate. Circular dichroism studies showed that water fraction comprised of α-helix and random coils, while salt and alkali fractions contained β-strand and coils., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Plant-based protein foods are increasingly common, but data on their nutritional protein quality are scarce. This study evaluated it for seitan (wheat-based food), tofu (soya-based food), soya milk, and a pea emulsion. The true ileal digestibility (TID) of their amino acids was determined in minipigs, to calculate the digestible indispensable amino acid score (DIAAS). The TID of the proteins was high and not significantly different between the foods tested: 97% for seitan, 95% for tofu, 92% for soya milk and 94% for pea emulsion. There were only minor differences in individual amino acid TIDs. DIAAS ranking was thus essentially driven by the amino acid composition of the food: soya-based food > pea emulsion > seitan. Nevertheless, the lower TID of sulphur-containing amino acids in tofu than in soya milk induced a significant decrease in DIAAS (from 117% to 97%), highlighting the importance of the matrix effect on nutritional protein quality., 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 © 2020 Elsevier Ltd. All rights reserved.)

This research investigates the effect of swarming season and sourcing geographical area on the nutrient composition of R. differens. On a dry matter basis, protein (34.2-45.8%) and fat (42.2-54.3%) are the major macro-nutrients. Leucine (80. 9-88.5), lysine (54.0-69.8) and valine (59.2-61.8) are the most abundant essential amino acids (EAA) (mg/g protein). Tryptophan is the most limiting EAA. Its EAA composition is like the children and adults' reference protein. Its fat is highly unsaturated (63.5-64.7). Oleic (38.4-42.7), linoleic (19.0-23.0) and palmitic (26.6-27.8) fatty acids (FA) (g/100 g total FA) are the most abundant. Geographical area significantly influences its mineral content within seasons. Season significantly influences its fat, protein, ash and mineral content but not its AAs' and FAs' content. Both factors significantly influence its vitamin B12 content (0.73-1.35 µg/100 g)., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Chinese quince seed protein isolate (CPI) was extracted using aqueous extraction and the isoelectric precipitation method, and its physicochemical and functional properties were investigated. Results showed that CPI contained all essential amino acids with exception of methionine which met the minimum recommendations for adults (World Health Organization/Food and Agriculture Organization). The electrophoresis analysis of sodium dodecyl sulphate polyacrylamide gel indicated that the molecular weights of protein fractions were approximately 15-60 kDa. Differential scanning calorimetry analysis was conducted, and the denaturation temperature of CPI was 103.4 °C. The surface hydrophobicity of CPI was found to be 932.80. The experiments showed that CPI had high emulsifying capacity, foaming stability, water holding capacity and oil adsorption capacity. Moreover, CPI also had outstanding gel formation capacity since its least gelation concentration of CPI was only 8%. All these results implied that CPI could be a nutritional protein resource and functional ingredient in the food industry., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Bresaola made from New Zealand mutton and lamb, were compared in quality attributes. Mutton bresaola had slightly lower protein and higher moisture contents, and similar amount of intramuscular fat and instrumental colour compared to that of the lamb. 36 and 80 unique endogenous peptides were observed in mutton and lamb, respectively. Proteolysis during dry-curing was affected by the age of the animal and has resulted in softer and easier to chew textural properties to the mutton bresaola. Significantly higher amounts of total free amino acids and higher proportion of essential amino acids were detected in the mutton bresaola from digestion simulation compared to that from lamb. Expedited proteolysis measured in the form of the release of free amino acids was positively related to the animal age. Overall, bresaola from mutton had more favourable characteristics compared to that of the lamb., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

In our study, semolina flour was substituted with beef emulsion (EM) at three different levels of 15, 30 and 45% (w/w) to develop a pasta with enhanced nutritional profile. The protein, fat, and water content significantly increased with addition of meat. The addition of meat enhanced the pasta gluten network. The redness and yellowness of cooked pasta increased with meat addition. Tensile strength increased from 0.018N/mm(2) in the control sample to 0.046N/mm(2) in 45% beef emulsion (45EM) sample. All meat-containing samples had significantly higher elasticity than control (0.039N/mm(2)). GI significantly decreased and IVPD value increased in 45EM sample. Five essential amino acids (leucine, lysine, methionine, threonine, tryptophan) in pasta digesta increased significantly with increasing meat addition., (Copyright © 2016 Elsevier Ltd. All rights reserved.)