The peptides remaining after phenol removal from a co-product of the alfalfa industry have various applications: in the food industry (as an additive), in therapeutic nutrition (high-value protein, peptides with opioid or immunostimulant activities, etc.), and in cosmetics. Hydrolysis of alfalfa white protein concentrate (AWPC) by an industrial enzyme (Delvolase) improved its solubility and nutritional properties. But, colored peptidic hydrolysate was observed. This color change was due to phenolic oxidation at alkaline pH. A combined ultrafiltration process and sorption technique was investigated. A ZrO2 Carbosep membrane (nominal molecular weight cutoff of 10,000 Da) allowed a 51% color reduction and a 96% peptide transmission. The colored peptide fraction in the permeate had a known and reproducible molecular-weight distribution. Permeate polyphenol removal was performed by a sorption technique. A polystyrene resin, Amberlite IRA900Cl, packed in a column, allowed a 92–95% phenol extraction while preser...

There is growing interest in the evaluation of stress, health and welfare of farm-raised fish. However, there is no scientific consensus about the methodology that is used to assess them. Sturgeon aquaculture is a recent industry with increasing interest in the production of caviar, which is characterized by high turnover and costs. To improve aquaculture efficiency, this study was conducted on routine blood samples, taken from Siberian sturgeon (Acipenser baerii), to test the robustness of using only physiological indicators to assess heat stress, health, and welfare. Sampling was performed after 1 month of prebiotic dietary supplementation followed by 4 weeks of sublethal heat stress. Data interpretation was achieved with a multivariate statistical tool. The expression of heat shock proteins (HSP) was assessed for the first time in sturgeon erythrocytes. Hsp70 and hsp90 expression was triggered by both stress and dietary supplementation. Indicators of non-specific immunity were modified mainly by stress. Complement activity increases with stress while lysozyme activity decreases, but to a lesser extent in supplemented fish. The antioxidant capacity increases with stress while oxidant metabolites decrease and overall oxidative stress was lower for fish that received dietary supplementation. The positive impact of dietary supplementation on health status was observable after a stress challenge. A principal component analysis was used to combine all the measured parameters and to observe patterns in physiological fish status. The four experimental groups of fish were clearly discriminated with this statistical tool. Physiological indicators from blood samples may enable heat stress, health, and welfare to be assessed in Siberian sturgeon.