Effect of high hydrostatic pressure on pasting properties, volatile flavor components, and water distribution of cooked black rice

The effect of high hydrostatic pressure (HHP) on pasting properties, volatile flavor components, and water distribution of cooked black rice (BR) was investigated. BR samples were subjected to HHP treatments at 200, 300, 400, and 500 MPa for 15 min, and then cooked for further evaluation. Results showed that HHP-treated samples exhibited lower viscosity compared to the control group, with the lowest value at 500 MPa. Among 126 flavor compounds identified in cooked BR stored for 7 days, the total contents of three key flavor components (alcohols, ketones, and aldehydes) were greatly enhanced, indicating that HHP contributed to the aroma quality of cooked BR. Water characteristics were determined by low-field nuclear magnetic resonance (LF-NMR), and three water fractions were detected and identified as T-21, T-22, and T-23. The value of T(21)gradually decreased with the increase of pressure, suggesting that HHP reduced the retrogradation degree of cooked BR. Practical applications This paper provides information on the potential benefits of HHP processing on pasting properties, volatile flavor components, and water distribution of cooked BR. Our results demonstrated that HHP-treated BR samples exhibited lower viscosity in terms of PV, TV, BD, FV, and SB. Considering the aroma quality of cooked BR, HHP, as an effective food processing technology, has the potential to retain flavor compounds in food. Therefore, this study would provide technical support for the commercial application of HHP-treated cooked BR.