The Study On Camellia Seed Oil Quality By Aqueous Enzymatic Extraction And Recovery Of Saponin Crude Extract Products From The Hydrolyzates

At present,the aqueous enzymatic extraction of Camellia seed oil was studied with the main aspects focused on the extraction technologies of different enzymes and demulsification.However,oil quality is directly related to the extracting process and technology.And there haven't been comprehensive reports about oil quality analysis of different aqueous enzymatic extractions.In this paper,based on the former established oil extracting technology,the differences of oil quality and water phases' compositions under carbohydrase and alkaline protease action were studied.And the saponin crude extract from water phase for recycling process and properties were analyzed.These research can provide the references of oil quality control and storage.And the basis of efficient recovery and subsequent use of the hydrolyzates were developed.The main research results are as follows:(1)Comparison of the oil physical and chemical properties.The camellia seed oil extracted by carbohydrase and alkaline protease extraction technology approached the refined oil.Except for the linoleic acid less than 7%,the refraction coefficient,iodine value,saponification value,saponification material,saturated fatty acid and oleic acid were in accordance with the characteristics of camellia seed oil standard.And the indexes of color,transparency,moisture and volatile matter,impurities,acid value and peroxide value met the standard of National I camellia seed pressing oil.Besides,the conjugated diene and p-anisi dine value were low.The vitamin E,phenols and phosphorus content of carbohydrase extracted-oil(A)relatively were 26.5 mg/100g,5.10 ug/g and 5.45 ug/g,which compared to the alkaline protease extracted-oil(B)were 25.3 mg/100 g,4.83 ug/g and 4.58 ug/g.In terms of oxidation stability,the induction period time of oil A at 110 ?was 16.11 h and shelf life was up to 25 months.Oil B was 13.39 h and shelf life was up to 19 months.The results showed that the enzymolysis process parameters of pH,temperature and time had no effects on the color,refraction,saponification value and iodine value.The types of enzymes did not affect the fatty acid composition.However,pH,temperature and time affected acid value,peroxide value and the oxidation level.Acid enzyme system promoted higher acid value.High temperature and long duration increased the peroxide value and the lever stability of oxidation.(2)The hydrolyzates of the aqueous enzymatic extraction synchronously contained large amounts of soluble substances,in which the protein/peptide content(dry basis)was 13%?16%,tea saponin 39 mg/ml?44 mg/ml,polysaccharide 47 mg/ml?51 mg/ml and a bit polyphenols and flavonoids.Peptides in the hydrolyzates molecular weight distribution had obvious differences,over 90%of alkaline protease hydrolyzates peptide were less than 2000 Da and carbohydrase hydrolyzates accounted for only 54%.98%of polysaccharide molecular weight distribution were less than 3000 Da.The average molecular weight respectively were 1332 in carbohydrase hydrolyzates and 2035 in the alkaline protease hydrolyzates.(3)Using material circulation to sample tank mode for concentration,the concentration operating conditions nanofiltration membrane were studied.Operating pressure to 10 bar,feed flow 406 L/h,the operating temperature 25 ?-35 ? was determined to concentrate the hydrolyzates,and the optimized concentration multiple of carbohydrase and alkaline protease hydrolyzates were 5.15 times and 5.64 times respectively.Used pH = 11 NaOH solution to clean nanofiltration membrane concentrated acid hydrolyzates,reoccupy water washing to neutral;Used the pH = 3 citric acid solution to clean nanofiltration membrane concentrated alkaline hydrolyzates,reoccupy water washing to neutral,and the membrane flux recovery coefficient were up to 97%.So using nanofiltration membrane can be effective in hydrolyzates recovery.(4)Spray drying concentration to get saponin crude extract products.The operating conditions of spray drying were:the inlet temperature was 180 ?,export actual temperature was 80 ?-90 ?,and peristaltic pump flow rate was 40%.The products after spray drying were pale,and carbohydrase product yield was 71.6%,while the alkaline protease product yield was 65.4%.After testing,the crude extract saponin products in terms of properties and composition met the standard of feed additive saccharicterpenin.The quality indexes were superior to the standard,which were total saponins content was 4%-46%,total sugar 31%?32%,crude protein 16%?21%,dry weight loss rate 1%?3%,crude ash 4%?6%.