Research on emergency instant rice quality improvement

To explore effects of different drying methods and ultra-high pressure treatment on instant rice quality, hot-air drying, microwave drying, and vacuum-freeze drying techniques were employed to dry rice materials with different particle sizes （100%, 75%, 50%）after ultra-high pressure treatment．Hardness, gelatinization characteristics, and rehydration properties were measured, and one-way analysis of variance（ANOVA）was conducted to analyze experimental results using SPSS 27.0 software．Results indicated that emergency instant rice hardness decreased after ultra-high pressure treatment, with the most significant change observed in rice treated at 200 MPa, which was about 44%．Different drying methods had a significant impact on rehydration properties of emergency instant rice（P<0.05）, with vacuum-freeze drying samples exhibiting the lowest hardness after rehydration, a decrease of about 60%．The highest rehydration rate of 276%, the shortest rehydration time of 283 s were achieved with 200 MPa and 50% particle size sample, followed by the hot air drying group and the highest hardness in microwave drying group．