The study of microwave heating time on chemical and microbiological properties and sensory evaluation in sweet fermented glutinous rice (Khao-Mark)

This research aims to study about the effect of microwave heating time on chemical and microbiological properties and sensory evaluation of sweet fermented glutinous rice (Khao-Mark) during storage times (8 days). The results revealed that all heating times did not affect to chemical properties and sensory evaluation (P 0.05) but TPC at 49 and 56 sec heating times decreased much more than others. During storage time, moisture, acid and alcohol contents of non microwave heating treatments were significantly increased 8.91, 29.16 and 19.14%, respectively whereas sucrose contents and pH values of those treatments were decreased 55.18 and 8.53%, respectively. Moisture, acid and alcohol contents of microwave heating treatments at 56 sec were increased 3.74, 10.89 and 12.5% while sucrose content and pH were decreased 46.63 and 2.84%, respectively. However, the chemical properties of 28 – 56 sec of the microwave heating treatments from day 6 were changed lower than others. The heating time for 49 and 56 sec showed significant reduction for TPC compared with others during storage. In conclusion, the appropriate microwave heating time for Khao-Mark was 21 sec due to no significant difference of the chemical properties when compared with the treatments of 35 - 56 sec (P 0.05).