High-pressure and thermal processing of cloudy hawthorn berry (Crataegus pinnatifida) juice: Impact on microbial shelf-life, enzyme activity and quality-related attributes

Abstract

The study aimed to evaluate the effect of high-pressure (HPP, 300/600 MPa for 2 and 6 min) and thermal processing (TP, 65 °C/30 min) on microbial shelf-life, enzyme-activity and quality-attributes of cloudy hawthorn berry juice (CHBJ) after processing and during storage (4 °C). The CHBJ shelf-life was at least 150 days when processed by HPP. No significant difference was observed in pH and titratable acidity (p > 0.05), while HPP significantly increased soluble sugar (p < 0.05) and simulated some fruity aroma compounds which improved the taste and flavor of CHBJ. However, HPP inhabited ineffectively enzyme-activity in comparison to TP, causing significant color changes (ΔE = 4.98 ± 0.03–5.10 ± 0.07) during 30-day storage (p < 0.05). Although particle size increased after HPP treatment, significant increases (68.76%-926.95%) were observed in viscosity (p < 0.05), due to enhanced extractability or modification of pectin induced by HPP, resulting in higher consistency of CHBJ. HPP is promising to extend shelf-life and improve quality-attributes of CHBJ.