Study On Functional Property And Application Of Kiwi Fruit Seed Oil Based On Ultra-fine Processing

The conditions of extraction, separation and anti-oxidative stability of the kiwi fruit seed oil which was extracted by the supercritical CO2were studied with the kiwi fruit seed from the fruit residue as raw material, and its physicochemical characters and quality indexes were determined and analyzed; the ultra-high pressure homogenizing conditions that made the kiwi fruit oil particle size reached the ultra fine state and the distribution characteristics of the particle diameter were researched, then further carried out the research on the health care effects of the kiwi fruit seed oil by ultra-fine processing and its safety evaluation through constructing the animal experimental model; and on this basis, also performed relevant application research, such as soft capsule and skin care product. The research results were as follows:①Optimal conditions for extracting the kiwi fruit oil by the supercritical CO2method:fruit seed grinding degree,40-60mesh; extraction pressure,30MPa; extraction temperature,48℃; CO2flow rate,300kg/h; extraction time,210min; and oil yield,34.4%; the free fatty acid and water could be further separated from the kiwi fruit seed oil which was extracted by the supercritical CO2if two-step depressurization separation method was used, and optimal separation conditions were as follows:the pressure and temperature of the separation pot Ⅰ, respectively9MPa and42℃; those of the separation pot Ⅱ, respectively6MPa and room temperature; kiwi fruit oil rate,32.3%; both the temperature and illumination condition could accelerate the oxidation of the kiwi fruit seed oil, so it shall be low temperature stored preserved without light and the anti-oxidative stability could be improved by adding the composite antioxidant which was made up of0.1‰TBHQ,0.1‰BHT and0.05‰VC.②The refining technology of the rejected product of the kiwi fruit seed oil was optimized. And optimal acid removal conditions were as follows:initial temperature of the alkali refining,35℃; concentration of the alkali liquor,9%;alkali refining time,5min;whisk speed,60r/min; thermal subsidence,8h; and optimal dehydration conditions were as follows:temperature,105℃; time,55min; whisk speed,45r/min; vacuum degree,0.08Mpa; and decolorizing conditions were as follows:adding activated clay,2.5%; decolorizing temperature,95℃; vacuum degree,0.08MPa; whisk speed,55-60r/min; time,30min, and then filtering through the frame filter: and deodorization conditions were as follows:deodorization temperature,150℃; time,2.5h; vacuum degree,0.08Mpa; filling in N2to remove the vacuum degree after deodorization had been finished and storing at a low temperature of0-5℃.③Physicochemical characteristic indexes of kiwi fruit seed oil were as follows: relative density,0.927; refraction Index,1.484; smoke point,160℃; saponification ratio,182mgKOH/g; iodine value,171g I2/100g; and main compositions of the fatty acid included:linolenic acid,64.3%; linoleic acid,13.3%; oleic acid,14.5%; palmitic acid,5.6%; and stearic acid,1.3%; and the kiwi fruit seed oil was the nowadays main source of the most ideal natural polyenoic acid.④Optimal conditions for preparing the ultra-fine kiwi fruit seed oil through the ultra-high pressure homogenizing technology were as follows:operating pressure,135MPa; flow rate of sample,70L/h; the oil particle size can be made minimum if the kiwi fruit seed oil was treated3times; the photon correlation spectroscopy method was used to test the common kiwi fruit seed oil particle size:the oil droplets with the particle size more than2μm took up97.891%, the particle size of100%oil droplets was less than6μm and the average particle diameter was3.0536μm, all of which showed that the oil particle size of kiwi fruit seed oil was within the micron range; and oil particle size of100%ultra-fine kiwi fruit seed oil was less than0.1972μm, thereinto, oil droplets with the particle size less than100nm reached88.594%and the average particle size was0.0634μm, which was shrunk48.2times than that before the ultra-fine processing; SEM analyzed that the common kiwi fruit seed oil droplets were disorderly without regular geometric shapes, while those of the ultra-fine kiwi fruit seed oil were more dispersed and the shape was ball-type and the specific surface area was relatively large.⑤The experiment of regulating blood lipid showed that both the common and ultra-fine kiwi fruit seed oils could reduce the TC and TG level, and enhance the HDL-C level of the white rats in the hyperlipemia animal model, however, both of them could more effectively reduce the TG level; the effectiveness for adjusting the blood fat of the ultra-fine kiwi fruit seed oil was more remarkable than that of the common kiwi fruit seed oil, especially the effectiveness of low-dosage ultra-fine kiwi fruit seed oil (0.335g/kg-BW) was outstanding; in details, the decreasing amplitude for TC level of the hyperlipidemic rats was48.67%, that for TG level was53.25%and the increasing amplitude for HDL-C level was201.41%, which were respectively10.5times of the TC and2.3times of the TG decreasing amplitude, and9.2times of the HDL-C increasing amplitude of the common kiwi fruit seed oil; and the oxidation resistance test showed that both the ultra-fine and common kiwi fruit seed oils could reduce the MDA content of the model mice of liver injury by monobromo-benzene, however, the decreasing amplitude of MDA of the former was4.8times of that of the later; both of the kiwi fruit seed oils could remarkably strengthen the SOD vitality in the blood serum of mice, but the increasing amplitude of the former can reach190.05%, which was3.2times of that of the later; the survival test results of the drosophila showed that both of the kiwi fruit seed oils could prolong the average life span and maximum life span, but the effectiveness of the former was more obvious than that of the later.⑥After rats were fed by ultra-fine kiwi fruit seed oil for30d, their growth&development, hematology index and blood biochemical index were not affected, and pathomorphological changes were also not found, all of which could offer a preliminary determination that the ultra-fine kiwi fruit seed oil was safe for human body.⑦Prepared the ultra-fine kiwi fruit seed oil soft capsule with the ultra-fine kiwi fruit seed oil as raw material based on its health care functions and safety evaluation results. When the mixture ratio of the capsule shell (water:gelatin:glycerol) was1:1:0.5, the quality of the soft capsule was the best; it's proper to determine the thickness of the ultra-fine kiwi fruit seed oil capsule shell as0.60mm, which could avoid delay of disintegration; drying conditions of the soft capsule were as follows: drying temperature,25℃; relative humidity,30%; and drying time,30h; the disintegration time limited of the soft capsule was prolonged as the storage temperature increased, so the long-time storage temperature shall be controlled below35℃; prepared the skin protector serum and cream with skin care effect by using the ultra-fine kiwi fruit seed oil as the base material, and the cosmetic patch test results showed that adverse reactions for human skin were not caused by this product.The above study could not only further make clear the remarkable nutrition and health care value of the ultra-fine kiwi fruit seed oil so as to widen its range of application, but also be favorable to further improve the application basic research level of the kiwi fruit industry of China and perfect the theoretical system of effect research on the ultra-fine functional oils.