Study On The Technology Of Removing Volatile Odor In Dunaliella Salina

Dunaliella salina contained much beta-carotene,protein,polysaccharide,and it has importmant economic value at food processing,health and medical,chemical engineering industry.However,its unique fishy limited partly development and application.The volatile components in Dunaliella Salina were determined by headspace solid phase microextraction(SPME)and gas chromatography-mass spectrum(GC-MS).The result showed that 47 volatile compounds in Dunaliella Salina were isolated and identified.Alcohols,ketones,aldehydes and carboxylic acid were the primary contents,representing 93.69%of the total volatile compounds as described.The fragrance,fishy and pungent odor were the main flavor in Dunaliella Salina.The fragrance components,such as β-cyclocitral,P-ionone,a-ionone and 3,5,5-Trimethyl-3-cyclohexene-l-one etc.were mainly produced by β-carotene metabolism or degradation.The fishy odor compounds primarily included 2-camphanol,trans-bicyclol[4.4.0]decan-1-ol-3-one,isophorone etc.The pungent odor compounds primarily included furan-3-carboxylcacid-5-tert-butyl-2-p-tert-butyl-phenoxymethyl,5-isopropyl-2-methylphenol as well as 2,6-diethyl-pyrazine etc.The effect of white sugar,Vc,neutral protease,β-cyclodextrin,citric acid,jasmine tea and NaOH on deodorization in Dunaliella salina were studied.And the optimal dosage were 100 g/L,5 g/L,0.03 g/mL,5 g/L,2 g/L,2.5 g/L and 0.5 g/L respectively.Jasmine tea had the best deodorization effect,and the optimum conditions were 40℃ water bath heating 30 min.NaOH has poor deodorization effect,what’s more,an unpleasant smell was found.The β-carotene contents in Dunaliella salina were reduced by 19.6%and 35.3%respectively after jasmine tea deodorizating and water deodorizating.The fishy in Dunaliella saliva was closely related to processing methods,and the fishy was least after freeze-drying,followed by low-temperature freezing for 24 hours and then by 100℃ constant temperature hot air drying,low temperature freezing 24 hours and then 50℃ constant temperature hot air drying,50℃ constant temperature hot air drying,100℃ constant temperature hot air drying.Jasmine Tea can instead of low temperature in deodorizationThe volatile compounds in Dunaliella Salina processed by different methods were determined by HS-SPME-GC-MS,and the results showed that the kinds of volatile compounds were least when Dunaliella Salina was deodorized by Jasmine Tea and then dried by 50℃ constant temperature hot air,namely 17 sorts.The fragrance compounds,accounting for 64.17%of the total,were main component of volatile substances in freeze-dried algae powder.High temperature dry treatment decreased the relative content of fragrance compounds,but increased the relative content of the fishyodor compounds and the pungent odor compounds.