Research On The Brewing Technology Of Kiwi Spirit

Actinidia plant origins from China, it has wide distribution, abundant resources and various kinds of species. The cultivated area and productivity in China rank first in the world. However, our country faces many problems, such as the product of a single, lack of processing ability and market development, which makes the raw material corruption. The Kiwi brewing spirit is beneficial to promote the development of characteristic agricultural products, increases the farmers’income and enhances the value of Kiwi. Now there are some studies on Kiwi wine, but there is few of studies on Kiwi spirit.Using the Actinidia as raw materials, the fermentation process conditions of Kiwi spirit were optimized by the response surface test. The change of nutrition compositions in fermentation was studied. And the aroma components of Kiwi spirit in distilling and aging were studied by the solid-phase micro extraction (SPME) and the gas chromatography-mass spectrometry(GC-MS). The conclusions were as follows:(1) Based on the comparison of three kinds of yeast, three kinds of fermentation method and different initial sugar. The results showed that the appropriate brewing yeast was Active Dry Wine Yeast; the best way of fermentation was mixed juice fermentation; the appropriate initial sugar content was17%.(2) Based on the results of single factor test and the response surface experiment, the regression model of Kiwi wine fermentation conditions was Y=8.44+0.11A+0.26B+0.35C+0.18AB+0.20AC+0.35BC-1.61A2-1.36B2-1.43C2, were established by the statistical method. And the best fermentation technical parameters of Kiwi spirit were determined, which was pH3.55, addition of yeast0.15%, fermentation temperature20℃. It was closed to the model prediction value, which proved that this model could well predict the relationship between alcohol content and fermentation technical conditions of Kiwi spirit. (3) The fermentation rules of Kiwi spirit were studied. In the fermentation of the Kiwi spirit, the content of Vc was gradually declining, it was not significant in the later stage of fermentation; the content of total acid was gradually rising; the content of reducing sugar was gradually declining in the earlier stage and it was not significant in the later stage of fermentation; the alcohol content was gradually rising in the earlier stage of fermentation and it was little changed in the later stage of fermentation; in the earlier stage of fermentation, the content of soluble solids was gradually declining, and in the later stage of fermentation, it was little changed; the variation of pH in the whole process of fermentation was not significant.(4) To study the influence of distilling on the aroma components in the Kiwi spirit, the solid-phase micro extraction (SPME) and the gas chromatography-mass spectrometry (GC-MS) were adopted to identify the aroma components during the first distillation and the second distillation. The results showed that18of main aroma components (≥relative content1%) were identified. During two distillations, Ethyl hexanoate, ethyl caprate, ethyl laurate, ethyl octanoate, and3-methyl-butyl decanoate focused on the early and middle period of distillation. Myristate, ethyl palmitate, ethyl and2,6-di-tert-butyl-p-cresol were little changed. Capric acid, lauric acid focused on the later period of distillation. Decanoate, isobutyl acetate, amyl acetate, bitterness-3-methyl, butyl, iso-amyl alcohol, acetal and2-pentadecanone focused on the prophase of distillation. hexadecanoyl aldehyde focused on the middle period of distillation.(5) To study the influence of aging on the aroma components in the Kiwi spirit, the solid-phase micro extraction (SPME) and the gas chromatography-mass spectrometry (GC-MS) were adopted to identify the aroma components during the aging. The results showed that130of aroma components were identified. The relative content of17kinds of them was higher, which were acetate, acetal, isoamyl alcohol, isoamyl acetate and so on. Esters, acetals were gradually declining and alcohols, acids, aldehydes, ketones were gradually rising during the aging. After aging, the aroma substances of Kiwi spirit experienced the subtle dynamic change of balance, stable and mature, and Kiwi spirit became special delicate, soft, mellow, typical highlights.