Studies On The Technology Of The Enzymatic Extraction Oil For Almond

Enzyme extraction of plant oil was a new oil processing method. In the case of oil extraction process, two advantages were offered by this treatment: higher yields of oil and higher quality of the oil. In order to extend the scope of applying of this method, the technology of enzymatic extraction for Almond oil was studied in this thesis.The effects of each variable affecting the technology of aqueous extraction oil that was pretreatment before enzymatic hydrolysis, were studied by condition test and orthogonal test. Analysis of variance (ANOVA) results indicated that the only factor, which significantly contributed to the oil-extracting rate, was temperature (P<0.05). The order of effect of each factor on aqueous extraction: temperature>pH value>the rate of solid to liquid>time of aqueous extraction. The optimum conditions of extraction oil by water was crushing the material, the ratio of solid to liquid 1:3, soaking in water of pH8.5 and 50℃ for 1.0h, grinding with water to 100 mesh of particle size, filtering and washing, the more than 96% of total oil could be extracted into almond milk.The almond milk was hydrolyzed by "1398" neutral protease. The results of condition test showed that temperature 45℃-60℃, pH7.0-7.5, time of more than l.0h favored the efficiency of the enzymatic treatment.In this thesis, two methods of aqueous enzymatic hydrolysis were used to extract for almond oil, enzymatic hydrolysis in almond milk and enzymatic hydrolysis in protein milk isolated from almond milk.The technology of directly enzymatic hydrolysis in almond milk and extracting was studied by condition test and orthogonal test. Analysis of variance results indicated that during enzymatic hydrolysis the factors, which significantly contributed to the oil-extracting rate, were temperature of enzymatic hydrolysis and enzyme concentration (P<0.05); the order of each factor: temperature>enzyme concentration>pH value>time of hydrolysis, and during organic solvent extracting the only factor, which significantly contributed to the oil-extracting rate, was pH of milk (P<0.05); the order of each factor: pH of milk> temperature>time>amount of solvent. The optimum conditions were adding enzyme concentration 2000IU per gram almond, hydrolyzing in almond milk of pH7.5 and 60℃ for l.0h, stopping enzyme hydrolysis in pH4.5, adding petroleum ether concentration 1:3, extracting at milk of 35℃ for 15 minutes. The extracting oil yield was 84.23%.The technology of enzymatic hydrolysis in protein milk isolated from almond milk and extracting was studied by condition test and orthogonal test. Analysis of variance results indicated that the only factor, which significantly contributed to the oil-extracting rate, wasenzyme concentration (P<0.05). The optimum conditions were centrifuging in milk of pH5.0 for separating protein with 85.16% oil, adding water that was as four times as separated protein, and blending for protein milk, adding enzyme concentration 1500IU per gram almond, hydrolyzing in milk of 50* and pH7.0 for 1.5h, stopping hydrolysis with pH4.5, adding petroleum ether concentration 1:3, extracting at milk of 35* for 15 minutes. The extracting oil yield is 81.38%.The technology of almond milk directly hydrolyzed by enzyme in which the oil-extracting rate was higher, operation was simpler and energy requirements was lower than enzymatic hydrolysis in protein milk isolated from almond milk, was suitably used to extract oil for almond.