Effects of high pressure processing on the quality of pickled radish during refrigerated storage

Abstract

Abstract The objective of this study is to investigate effects of high pressure processing (HPP) on the organoleptic properties of pickled radish during refrigerated storage. Under the HPP treatment at 550 MPa/5 min, total plate count (TPC) decreased by 5.57 log 10 CFU/mL, and yeasts and molds (Y&M) were totally inactivated. There is no significant difference in the microbiological index between HPP and thermal processing (TP) at 80 °C/20 min and both samples showed microbiologically safe during 60-day storage at 4 °C (TPC 10 CFU/mL). HPP showed significant impact on pH, hardness and color of pickled radish, whereas had less microstructural damage of pickled radish tissues. In comparison with TP-treated pickled radish the flavor of HPP-treated pickled radish was more preferable. Since HPP increased the abundance of linalool, citronellol and citral and reduced the abundance of sulfide and terpinolene, resulting in the increase of sweetness and the decrease of stimulating flavor. Industrial relevance This study was intended to develop better quality and more stable pickled radish without preservative, which is not available on the market now. There is little knowledge on the influence of HPP on the quality of pickles, such as color, texture and flavor. In this study, HPP showed significant impact on pH, hardness and color of pickled radish, whereas had less microstructural damage of pickled radish tissues. HPP treatment could be applied for the inactivation of microorganism, and they were microbiologically safe (TPC 10 CFU/mL, Y&M were not detected) during 90-day storage at 4 °C. In comparison with TP-treated pickled radish the flavor of HPP-treated pickled radish was more preferable. This study provided a comprehensive technical support for the application of HPP in pickles processing.