Effect of Pasteurization, UHT and Microwave Treatment on Quality of Blueberry Juice

Abstract:

In order to explore the effect of pasteurization，UHT and microwave treatment on quality of blueberry Juice，the aroma of Blueberry Juice were identified by using head space solid phase micro-extraction（HS-SPME/GC-MS） combined with GC-MS，and the parameters，including microflora，nutrients and DPPH free radical scavenging ability，were analysis. The results indicated the 47 volatile aroma components of blueberry Juice，mainly alcohols，esters，olefin，ketones and aldehydes，were identified，the relative content of different thermal treatment blueberry juice has significantly different，it accounted for about 45.66%~84.53% of aroma components. The aroma components of microwave treatment sample up to 25 species. Microwave sterilization can effectively kill microorganisms of blueberry juice，the changes of total soluble solids and total acid content are low，and contents of anthocyanins and polyphenols highly retained rate，DPPH free radical scavenging capacity of microwave treatment were up to 89.22% after storage 90d. Microwave sterilization not only kill the acid-resistant micro-organisms，maintain the nutrition，DPPH free radical scavenging capacity and color，but it also have a pleasant aroma，is a very promising sterilization methods.