Optimization of Processing Conditions to Improve the Rehydration and Sensory Properties of Freeze‐Dried Cooked Rice

• Published in: Journal of food processing and preservation Vol. 38; no. 3; pp. 1244 - 1250
• Main Authors: Song, Beom‐Seok, Park, Jae‐Nam, Lee, Ju‐Woon, Kim, Jae‐Kyung, Kim, Jae‐Hun
• Format: Journal Article
• Language: English
• Published: Blackwell Pub 01.06.2014; Blackwell Publishing Ltd
• Subjects: absorption; Back propagation; cooking; crystals; dried foods; Foods; Freezing; freezing point; Frozen; hardness; Heating; ice; Ice crystals; labor; leavening agents; manufacturing; Optimization; rehydration; Rice; sensory properties; soaking; stickiness; temperature
• ISSN: 0145-8892; 1745-4549
• DOI: 10.1111/jfpp.12085

This study investigated the effects of baking powder (BP) concentration, cooking temperature (CT) and freezing temperature on the rehydration ratio of freeze‐dried cooked rice (FDCR). Rehydration ratios increased with higher BP concentration in soaking solutions, with 0.3% being considered the optimal concentration. Greater rehydration ratios were recorded at a CT of 120C than 100C. Rapid freezing (−70C) produced small intracellular ice crystals, whereas slow freezing (−20C) produced large ice crystals, causing a higher ratio of initial water absorption. The combine‐treated FDCR, which was soaked in 0.3% BP, cooked at 120C and frozen at −20C, had a larger porous and spacious structure, as well as the highest degree of rehydration. Significantly higher stickiness/hardness ratios and sensory acceptability were obtained for the combined treatment compared to the conventional treatment (cooked at 100C and frozen at −70C). These results indicate that these preparation conditions could improve the sensory properties of FDCR at consumption. PRACTICAL APPLICATIONS: With the changing socioeconomic pattern of life, convenient foods are becoming popular because they save time and labor. The result of this research could be applied to manufacture ready‐to‐cook rice‐based dried foods of improved sensory quality and quick preparation time.