Impact Of Chromium On The System Matt And Beer Fermentation

Barley is the main stuff of beer brewing and chromium is a vital trace element to human. Potassium chromium sulfate was added to the water during the barley infusion and enriched-Cr malt was executed. This article studied the effects of chromium on biological characteristic of malt and on malt quality. Wort formed after mashing and was used to ferment. This article studied the effects of chromium on biological characteristic of beer yeast and on ferment outgrowth. The content of total chromium and organic chromium in malt, in wort and in fermented broth were also mensurated. The results were as follows:(1)During the course of germination, respiratory intensity, the activity ofα-amylase, peroxidase and polyphenoloxidase of malt which was treated with KCr(SO₄)₂ increased. Respiratory intensity, the activity ofα-amylase achieved highest which was 1.78, 1.45, times of the controls when KCr(SO₄)₂ concentration was 150 mg·kg^-1, the activity of peroxidase and polyphenoloxidase achieved highest which was 1.37 and 1.25 times of the controls when KCr(SO₄)₂ concentration was 100 mg·kg^-1. Mash time of malt reduced when KCr(SO₄)₂ concentration was between 25²00 mg·kg^-1, and mash time was shortest when KCr(SO₄)₂ concentration was 100 mg·kg^-1. The pH value of enriched-Cr malt was under the contrast and it is suit to the growth of beer yeast when KCr(SO₄)₂ concentration were 100, 150 and 200 mg·kg^-1. Chroma of enriched-Cr malt also increased. The content ofα-amino-nitrogen achieved highest which was 212.2 mg/100g when KCr(SO₄)₂ concentration was 150 mg·kg^-1. When KCr(SO₄)₂ concentration was 200 mg·kg^-1, the content of extraction achieved highest which was 77.9%. Diastatic power also enhanced except that the KCr(SO₄)₂ concentration was 250 mg·kg^-1. When KCr(SO₄)₂ concentration was 100 mg·kg^-1, diastatic power and total score achieved highest which were 311.2 W·K and 57.3.(2)Beer yeast grew rapidly in wort when KCr(SO₄)₂ concentration were 25 200 mg·kg^-1. Yeast growed weakly when KCr(SO₄)₂ concentration was 250mg·kg^-1. Cells of...