Aseptic processing of apricots in syrup by means of a continuous pilot scale ohmic unit.

摘要

In the present study the effect of ohmic heating processing on the quality and shelf-life of apricots in syrup was investigated. Each 100 g of product contained 30 g of pre-heated syrup (15 degrees Brix) and 70 g of blanched apricot pieces with a cubic shape (size 1.2 cm). The liquid-solid mixture (pH <4) was pasteurized at 90 degrees C for about 113 s in a 30 kW aseptic continuous pilot ohmic system using a 25 kHz alternating electric current. The aseptically packaged samples were stored at 25 degrees C and periodically examined over one year period. The parameters measured during the preservation period were: pH, degrees Brix, color, ascorbic acid content, and microbial spoilage. During the shelf-life, no swelling of the packages was detected. Moreover, the product kept its microbiological stability during the whole storage period of 52 weeks. The ascorbic acid content was slightly reduced by the elctrothermal treatment. However, it was well preserved for the entire storage time. Similarly, the quality characteristics of the fresh apricots in syrup were not adversely affected by ohmic processing and a high retention of the quality attributes was observed during the storage time.