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Kiwifruit contains a variety of essential minerals and vitamins, also contains 17 kinds of free amino acids, especially the VC content is very rich, kiwifruit is also rich aromatic ingredients butyrate, ethyl butyrate, hexanal, thus constitute the kiwi has a unique scent. Kiwi in health care to treat indigestion, vitamin deficiency syndrome, hepatitis, respiratory disease. Which not only has the function of lowering blood cholesterol and triglycerides, prevent scurvy, atherosclerosis, coronary heart disease, high blood pressure have special effects; And with lowering blood pressure, lipid peroxidation, scavenging reactive oxygen free radicals and inhibit tumor cells, improve immune function and other aspects of the pharmacological activity. Long-term consumption of kiwi fruit drinks, can lower serum and erythrocyte malondialdehyde (MDA) content and improve the immune globulin levels, a significant anti-cancer and anti-fatigue effect, so the development of natural health kiwi fruit juice has broad prospects for development, with good economic and social benefits. In this paper, based on access to a large number of domestic and foreign literature, the choice of the new lines of Actinidia chinensis selected -815 \Micro-Extraction the the kiwi juice samples aroma of the traditional techniques and new technology preparation and GC-MS analysis, as follows: (1) through extensive literature research, the research progress of kiwi fruit juice are reviewed, including the kiwi juice situation and existing problems, kiwifruit mention (take) juice process, kiwi VC protection and color protection technology, kiwi juice clarification process, kiwi juice concentrate process, kiwi aroma components measured progress were described and explore and a variety of process characteristics compared Determination of aroma components in kiwifruit sample preparation techniques were analyzed and compared. Finally, the discussion of the trends of the kiwifruit juice. (2) by kiwi slices frozen test to determine the the kiwi slices freezing point and the shortest frozen time: slice the freezing point to -2.1 ° C, slices reached of -18 ℃ shortest freezing time of 4 hours, 9 minutes. (3) According to the slow freezing damage the cell wall of the principle of using the freeze-thaw centrifugal juice preparation kiwi juice of new technology, a single factor and orthogonal test analysis of the the frozen broken and centrifugal process parameters. The results show that: the broken frozen juice prepared by the process of centrifugal juice in the juice yield, VC content, light transmittance and color aspects are significantly better than traditional juicing process, the optimum conditions were as follows: slice thickness of 0.6cm, -14 ℃ freezer 10h, 30 ° C thaw 30min, 3000r/min centrifugal 20min, 100 mesh filter. (4) to explore the use of chitosan clarification kiwifruit juice amount of chitosan, to clarify temperature and to clarify the time the single factor test and orthogonal test analysis, the results showed that: Clarification of the before and after total sugar, total acid, VC, soluble solids, total phenolic content little change in transmittance is greatly improved and reached 95.9%. The protein content of 76.54 percent lower than the original juice. The optimum conditions for chitosan clarification: the chitosan dosage 0.4 g / L, under the conditions of a temperature of 40 ° C to clarify 60min. Clarify and membrane separation based on this comparison, studies show: membrane separation clarified chitosan clarification, but superior in the light transmittance and the removal of protein to chitosan clarification in reducing the VC and the loss of the total phenolic substance than the film separation clarify better, and less time-consuming. (5) the initial exploration aroma components of kiwi fruit as well as the preparation of traditional techniques and new technology kiwi juice samples using solid phase micro extraction and gas chromatography - mass spectrometry analysis, the results showed that: kiwi fruit and four juice Total aroma ingredients are: ethanol, ethyl acetate, 2 - hexenal, 2,6 - di-tert-butyl methyl phenol, menthol, ethyl butyrate, etc., these six substances are kiwi aroma main part of the new technology and traditional crafts have remained essentially the kiwi fruity. Original fruit juice aroma and frozen crushing the aroma of the juice obtained by the centrifugation juice and clarification process juice common aroma component: ethanol, ethyl acetate, 2 - hexenal, 2,6 - di-tert-butyl-methyl- phenol, menthol, ethyl butyrate, (E) -2 - hexene-1 - ol, trans - caryophyllene, 1 - limonene. The total of the components of the original fruit juice aroma and traditional process juice and clarification process of the obtained juice aroma: ethanol, ethyl acetate, 2 - hexenal, 2,6 - di-tert-butyl-methyl-phenol, butanoate ester, menthol. It can be seen, the the traditional crafts juice and clarify the process to get the juice, compared with the original fruit only retains all the aroma of these six types of substances, and the new process the juice and clarify the process to get the juices aroma in addition to retain a total of six components, but also retains the (E) -2 - hexene-1 - ol, trans - caryophyllene, 1 - limonene three main aroma components of the original fruit. The new technology can better retain the original fruit aroma components.
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