Effect of thermal pasteurization and high pressure processing on bioactive properties in strawberry juice

Abstract

In the current food industry, companies often offer new and revolutionary processing methods that allow to improve food properties. A prominent technology is High Pressure Processing (HPP), a non-thermal technology that arises as an alternative to the traditional thermal pasteurization (TP). With HPP it is possible to obtain food and drinks similar to the raw food while improving important nutritive and functional properties. Since strawberries are very important fruit in the human diet, the aim of this study was to study the effect of HPP and TP on selected qualitative-quantitative parameters of strawberry juices (HPSJ - High Pressure Strawberry Juice/TPSJ - Thermal Pasteurized Strawberry Juice). It seems that strawberries can have a positive effect on human health due to their high content in beneficial nutrients. From monitored parameters, significant differences (p < 0.001) were found between juices in the following parameters: antioxidant activity, β-carotene and zeaxanthin content. Higher antioxidant activity (1547.60 ±4.89 mg AA.L-1 FM vs. 1424.72 ±10.66 mg AA.L-1 FM) and zeaxanthin (1.34 ±0.11 μg.mL-1 FM vs. 0.89 ±0.08 μg.mL-1 FM) was found in HPSJ, comparatively to TPSJ. The content of β-carotene was higher in TPSJ (156.28 ±2.13 μg.mL-1 FM) than in HPSJ (122.02 ±4.28 μg.mL-1 FM). Results related to the polyphenols content showed significantly higher values (p >0.01) in HPSJ, compared to TPSJ (1100.04 ±17.16 mg GAE.L-1 FM vs. 1002.66 ±17.16 mg GAE.L-1 FM). The difference in the content of lutein (TPSJ 8.84 ±0.57 μg.mL-1 FM; HPSJ 8.17 ±0.13 μg.mL-1 FM) was not significant (p >0.05).