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===Protein degradation=== | ===Protein degradation=== | ||
During [[malting]] and [[mashing]], proteolytic enzymes (proteases) break proteins into smaller peptides or amino acids that are critical for brewing high-quality beer. Approximately 75% of wort protein is solubilized as a result of protein degradation during malting, and the remaining 25% of the final wort protein solubilized during mashing.<ref name=jones/><ref name=aldred/><ref name=jonesbudde/><ref name=kuhbeck/> As such, proteolytic activity during mashing is especially important when unmalted cereal [[adjuncts]] are used. Overall, efficient degradation of the hordein storage proteins of barley in malting and brewing is essential for several reasons: | During [[malting]] and [[mashing]], proteolytic [[enzymes]] (proteases) break proteins into smaller peptides or amino acids that are critical for brewing high-quality beer. Approximately 75% of wort protein is solubilized as a result of protein degradation during malting, and the remaining 25% of the final wort protein solubilized during mashing.<ref name=jones/><ref name=aldred/><ref name=jonesbudde/><ref name=kuhbeck/> As such, proteolytic activity during mashing is especially important when unmalted cereal [[adjuncts]] are used. Overall, efficient degradation of the hordein storage proteins of barley in malting and brewing is essential for several reasons: | ||
* Hordein breakdown allows the release of starch into a form accessible by amylases.<ref name=aldred>Aldred P, Kanauchi M, Bamforth CW. [https://onlinelibrary.wiley.com/doi/abs/10.1002/jib.635 An investigation into proteolysis in mashing.] ''J Inst Brew.'' Awaiting publication. Accessed January 2021.</ref> Furthermore, proteinase activity directly increases the activity of the starch-degrading enzymes.<ref>Hu S, Dong J, Fan W, et al. [https://onlinelibrary.wiley.com/doi/pdf/10.1002/jib.172 The influence of proteolytic and cytolytic enzymes on starch degradation during mashing.] ''J Inst Brew.'' 2014;120(4):379–384.</ref> Protease activity is actually the parameter most closely tied to the amount of malt [[extract]] obtained from mashing.<ref name=osman>Osman AM, Coverdale SM, Cole N, Hamilton SE, de Jersey J, Inkerman PA. [https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.2002.tb00125.x Characterisation and assessment of the role of barley malt endoproteases during malting and mashing.] ''J Inst Brew.'' 2002;108(1)62–67.</ref> | * Hordein breakdown allows the release of starch into a form accessible by amylases.<ref name=aldred>Aldred P, Kanauchi M, Bamforth CW. [https://onlinelibrary.wiley.com/doi/abs/10.1002/jib.635 An investigation into proteolysis in mashing.] ''J Inst Brew.'' Awaiting publication. Accessed January 2021.</ref> Furthermore, proteinase activity directly increases the activity of the starch-degrading enzymes.<ref>Hu S, Dong J, Fan W, et al. [https://onlinelibrary.wiley.com/doi/pdf/10.1002/jib.172 The influence of proteolytic and cytolytic enzymes on starch degradation during mashing.] ''J Inst Brew.'' 2014;120(4):379–384.</ref> Protease activity is actually the parameter most closely tied to the amount of malt [[extract]] obtained from mashing.<ref name=osman>Osman AM, Coverdale SM, Cole N, Hamilton SE, de Jersey J, Inkerman PA. [https://onlinelibrary.wiley.com/doi/pdf/10.1002/j.2050-0416.2002.tb00125.x Characterisation and assessment of the role of barley malt endoproteases during malting and mashing.] ''J Inst Brew.'' 2002;108(1)62–67.</ref> | ||
* The liberated amino acids are required for yeast fermentation and they also contribute to color and flavor formation.<ref name=aldred/><ref name=osman/> With well-modified malt, the desired concentration of free amino acids is typically achieved as a result of protein degradation during malting.<ref name=kuhbeck/> | * The liberated amino acids are required for yeast fermentation and they also contribute to color and flavor formation.<ref name=aldred/><ref name=osman/> With well-modified malt, the desired concentration of free amino acids is typically achieved as a result of protein degradation during malting.<ref name=kuhbeck/> | ||