| Making vinegar in china has a very long history. It is an important component of ancient science and culture achievement. Vinegar is commonly used as sore flavouring materail. However vinegar is not only a kind of flavouring materail, it is good to human's health also. It can prevent and cure many kinds of diseases. Shanxi overmature vinegar contains a lot of bioactive substances which are healthful to human beings. In recent years, more and more microbiologists and medical workers have paid much attention to vinegar and made some progress in primary studies.In order to improve the output of vinegar and optimize its production technology, we had carried out the following research. First, the bacterial strain of high yield of acetic acid was screened out, and the strain was mutagenized and breeded by using complex mutagenesis of ultraviolet ray and lithium chloride. Then by using liquid fermentation method, batch of the strain was carried out. Second, the mutagenic method of N~+ ion impantation and ultraviolet ray were adopted in the breeding of saccharification enzyme-producer Aspergillus niger 4309. Finally, the three biochemistry process of making vinegar including saccharification, alcohol fermentation and acetic acid fermentation were studied and improved preliminarily.In the research of the bacterial strain of high yield of acetic acid, after lots of screening tests, a strain was obtained named No.12, and complex mutagenesis of ultraviolet ray and lithium chloride of No.12 was carried out. The yield of acetic acid of the mutant strain named No.30-123 may reach 4.2 gHAC/100ml. It was 1.01 times higher than the original strain. A series of experiments were carried out to find out the optimum medium compositions and the optimum cultivation conditions. By using liquid fermentation method, batch of No.30-123 was carried out. The highest synthetic speed of acetic acid may reach 0.1143gHAC/100ml·h, the transformation rate from alcohol... |
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