The protein fraction in LCB is usually easy to extract, especially for BSG that has a softer matrix. An example of mild conditions is described by Connolly et al. where BSG was put in the presence of water at 60°C for 18 hours before centrifugation and precipitation at -20°C. One of the interesting findings is the nature of the proteins with larger profile for pale BSG (59 % > 10 kDa) compared to black BSG (6 % > 10 kDa) and a high antioxidant profile thanks to a high TPC. Vieira et al. used a more sequential approach for protein and arabinoxylan extraction under basic conditions. Each hemicellulose extract was then acidified using citric acid (pH = 3) precipitating the proteins, recovered by filtration. The acid was then recovered by precipitation in ethanol to yield oligomeric arabinoxylose. Optimised extraction conditions were investigated using UAE yielding high amount of proteins from BSG (104.2 mg/gBSG) and subsequently 17 amino acids after enzymatic lyse. extract proteins from BSG without saccharides in alkaline conditions. [72] The simultaneous recovery of proteins and carbohydrates is also possible by using a mixture of carbohydrase and peptidase yielding hydrolysates to be used as prebiotic food supplement for example. As explained previously, the reported use of BSG is systematically performed on dry BSG for transportation and preservation purposes mainly, but this drying step comes with a non-negligible environmental cost. Tackling this issue, Connolly et al. proposed a more sustainable valorisation using wet BSG yielding protein-rich hydrolysate (< 5 kDa), with a different amino acid composition reported between pale and dark malt. To overcome the nongrinded nature of wet BSG, compared to the dry one that is easily shredded, the agitation was performed by an Ultra Turrax, to reduce particles size while keeping a good homogeneity. To summarise, protein extraction can be achieved easily using several methods.