THE EFFECT OF THERMAL AND NON-THERMAL TREATMENT ON THE SHELF LIFE AND QUALITY OF ONION JUICE

Abstract

The effect of thermal and non-thermal treatment on the quality and shelf life of onion juice has been studied. Two methods were used: pasteurization at 74.5 °C for 12 minutes and irradiation with ultraviolet radiation in the C range at 7.5 MW/cm2 for 30 minutes. Microbiological and physico-chemical parameters were evaluated during 12 weeks of storage at room temperature. It was found that both methods increased the duration of microbiological storage of juice by at least six times compared with the untreated sample. Heat treatment provided better preservation of color and acidity than ultraviolet treatment, and showed greater effectiveness in extending shelf life.