Defatted grape seed flour (DGSF), a byproduct of the grape seed oil production, was investigated as a potential source of protein-enriched food ingredients with functional properties. The operation conditions of the alkaline extraction followed by the acid precipitation method were studied by response surface methodology, aiming to maximize the protein extraction yield. These conditions were temperature 50 °C, solvent/meal ratio 1:15, pH 11, and 150 min extraction time in two sequential extraction cycles, achieving a product with 32.63 ± 0.07% (w/w) d.m. of protein content. A second extract with 38.17 ± 1.34% (w/w) d.m. of protein was obtained under the same conditions, but using an additional centrifugation step before the acid precipitation. The amino acid profile, solubility, water and oil retention capacity, and emulsifying and foaming properties of the DGSF and the obtained extracts were compared. Both extracts could be used as food ingredients with different nutritional and technological purposes.

Background: Consumption of fibre-enriched orange juice may be an appropriate way to supplement daily fibre intake and achieve beneficial effects on metabolic health. The present study aimed to assess the short-term effects of fibre-enriched orange juice on postprandial metabolism and satiety in a healthy adult population. Methods: In this double-blind, randomised, placebo-controlled, crossover study 10 healthy subjects underwent two one-day trials in which they consumed an orange juice beverage containing 1.4 g/100 mL of citrus fibre (29.3% soluble and 41.9% insoluble) or a placebo (regular orange juice without added fibre). Postprandial glucose, insulin, gut hormones (GLP1, GIP and ghrelin), leptin and qualitative appetite/satiety assessment were measured every 15 or 30 min over the 120 min test period. Results: The fibre-enriched orange juice decreased postprandial serum glucose and circulating insulin levels at 15 min compared with the placebo. In addition, after intake of the fibre-enriched juice, a significant effect on qualitative feelings of satiety and fullness was observed at 15 and 120 min, and was accompanied by a significant decrease in GLP1 response at 15 min. No significant changes were observed in leptin, GIP and ghrelin after juice intake. Conclusions: In healthy individuals, a single acute consumption of fibre-enriched orange juice has short-term beneficial effects on postprandial glycaemia, circulating insulin levels and satiety through GLP1 secretion.

High pressure processing (HPP) can improve oyster shucking yield immediately after the treatment and increase the microbiological and sensory shelf life of oysters stored at 0–4 °C. However, the evolution of shucking yield during storage has not been previously examined and there are no studies focusing on shelf life at higher storage temperatures. To elucidate both aspects, control and HPP (300 MPa; 2 min) offshore cultivated oysters (Magallana gigas) were stored at 4 and 10 °C for 14 days, analyzing shucking yield, color, texture, microbiological and sensory characteristics. HPP samples showed a higher shucking yield (17% on average) than controls with minimal impact in texture and color, regardless of storage time and temperature. At 10 °C, HPP delayed microbial growth and sensory deterioration, increasing the estimated shelf life of oysters by 3 to 4 days (aerobic plate count < 6 log cycles; overall sensory acceptability > 2). Compared to controls stored at 4 °C, HPP oysters stored at 10 °C presented the same shelf life (5 to 9 days) but with higher shucking yield (up to 25%). In conclusion, HPP is an excellent tool to increase the shucking yield and delay sensory deterioration of oysters stored at 10 °C.