Unveiling the Impact of Processing Methods on In Vitro Protein Digestibility: A Focus on Highland Barley and Its...

As one of the indispensable components of the human body, proteins not only participate in the construction of tissues, but also play an important role in maintaining the metabolic balance of the organism. However, in some protein sources, factors such as complex protein structures and the presence of anti-nutritional compounds reduce bioavailability. Processing methods can significantly enhance protein digestibility by overcoming these limitations. This review focuses on highland barley proteins and their application in winemaking. It summarises their composition, digestibility and functional properties. It also summarises and evaluates in vitro digestion models suitable for in vitro digestion of highland barley proteins. Then, this review investigates in depth the effects of different processing methods-including thermal treatments, enzymatic hydrolysis, and microbial fermentation-on the in vitro digestibility of highland barley proteins and their mechanisms during winemaking. It was shown that these processing methods achieve different degrees of in vitro protein digestibility improvement by altering the structure of highland barley proteins and altering the interactions with other substances, achieving efficient utilisation of high-quality highland barley protein resources. Finally, this review provides a prospect which opens up new ideas for the efficient utilisation of proteins in food processing in the future.