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A protein‐rich product (PP) with 46% protein and less than 1% fibre was recovered from brewery's spent grain. This study aimed to investigate the effects of replacing dietary fishmeal with PP on the growth, feed utilization efficiency and nutritional composition of Pacific white shrimp, Litopenaeus vannamei. The control diet (PP0, containing 35% fishmeal) was compared with four isonitrogenous (44% crude protein), isolipidic (10% crude fat) and isocaloric (20 kJ/g) test diets, PP10, PP30, PP50 and PP70, which were formulated using PP protein to replace 10%, 30%, 50% and 70% of fishmeal protein. Sextuplicate groups of shrimp (averaging 1.10 g) were fed each of the five diets for 8 weeks. The results showed that up to 50% of fishmeal replaced with PP did not negatively affect the shrimp survival, growth performance, feed utilization efficiency, or the protein content and amino acid profile of shrimp. However, replacing 70% of fishmeal protein with PP protein negatively affected the percent weight gain and specific growth rate of shrimp, although the shrimp survival rate and feed conversion ratio were not affected. [ABSTRACT FROM AUTHOR]

Brewer's spent grain (BSG) is the major waste generated by breweries, which contains 20-30% (w/w) proteins and 40-60% (w/w) of fibers. Technologies have been investigated to valorize BSG by extracting proteins from BSG; however, none of them has been implemented on an industrial scale due to the challenges including high drying cost of wet BSG, heavy chemical consumptions, and a large volume of secondary waste after protein extraction. Herein, a wet fractionation process was proposed to fully utilize BSG by simultaneously producing high protein product (HPP) and high fiber product (HFP) through the separation of proteins and fibers from BSG. The effect of different concentrations (1, 3, and 5%, w/w) of chemicals (sodium hydroxide and sodium bisulfite) and enzyme (Alcalase, 5, 20 and 35 µL/g dry BSG) treatments on product yield and composition was investigated to maximize the process separation efficiency and potentially reduce the chemical and enzyme consumptions. The sodium hydroxide and Alcalase treatments improved the protein and fiber separation compared to the sodium bisulfite treatment. Under the optimal condition (20 µL/g dry BSG) using Alcalase, the protein separation efficiency was 84%, and the protein concentration in HPP was 43% (w/w), almost double the protein concentration (23%, w/w) in original BSG. The fiber content of the HFP was more than 80% (w/w), of which hemicellulose is the dominant fiber component. [ABSTRACT FROM AUTHOR]

Raw cocoa beans were processed to produce cocoa powders with different combinations of fermentation (unfermented, cool, or hot) and roasting (not roasted, cool, or hot). Cocoa powder extracts were characterized and assessed for α-glucosidase inhibitory activity in vitro. Cocoa processing (fermentation/roasting) contributed to significant losses of native flavanols. All of the treatments dose-dependently inhibited α-glucosidase activity, with cool fermented/cool roasted powder exhibiting the greatest potency (IC 50 : 68.09 µg/mL), when compared to acarbose (IC 50 : 133.22 µg/mL). A strong negative correlation was observed between flavanol mDP and IC 50 , suggesting flavanol polymerization as a marker of enhanced α-glucosidase inhibition in cocoa. Our data demonstrate that cocoa powders are potent inhibitors of α-glucosidase. Significant reductions in the total polyphenol and flavanol concentrations induced by processing do not necessarily dictate a reduced capacity for α-glucosidase inhibition, but rather these steps can enhance cocoa bioactivity. Non-traditional compositional markers may be better predictors of enzyme inhibitory activity than cocoa native flavanols.

Cocoa is a concentrated source of dietary flavanols-putative bioactive compounds associated with health benefits. It is known that fermentation and roasting reduce levels of native flavonoids in cocoa, and it is generally thought that this loss translates to reduced bioactivity. However, the mechanisms of these losses are poorly understood, and little data exist to support this paradigm that flavonoid loss results in reduced health benefits. To further facilitate large-scale studies of the impact of fermentation on cocoa flavanols, a controlled laboratory fermentation model system was increased in scale to a large (pilot) scale system. Raw cocoa beans (15 kg) were fermented in 16 L of a simulated pulp media in duplicate for 168 h. The temperature of the fermentation was increased from 25⁻55 °C at a rate of 5 °C/24 h. As expected, total polyphenols and flavanol levels decreased as fermentation progressed (a loss of 18.3% total polyphenols and 14.4% loss of total flavanols during fermentation) but some increases were observed in the final timepoints (120⁻168 h). Fermentation substrates, metabolites and putative cocoa bioactive compounds were monitored and found to follow typical trends for on-farm cocoa heap fermentations. For example, sucrose levels in pulp declined from >40 mg/mL to undetectable at 96 h. This model system provides a controlled environment for further investigation into the potential for optimizing fermentation parameters to enhance the flavanol composition and the potential health benefits of the resultant cocoa beans.