Quality changes of HomChaiya rice beer during storage at two alternative temperatures

Abstract

A newly developed HomChaiya rice beer has several nutritional advantages and phytochemical benefits. However, the quality after prolonged storage is not yet known. The present study explored the quality changes of HomChaiya rice beer stored in glass bottles at two temperatures (4 °C for low and 25 °C for ambient) for an extended period (12 months). The beer was analyzed for physiochemical quality, phytochemicals, and antioxidant activity at one-month (30 days) intervals. Prolonged storage under ambient temperature slightly darkened the beer color. The CO₂ level in the stored beer was higher in ambient storage. The pH decreased with storage time, and acidic pH was noted for the beer in ambient storage. The alcohol content increased throughout the storage at both tested temperatures. Foam stability and density increased during storage, whereas viscosity and turbidity decreased. Free amino acids and total nitrogen gradually increased, and they were slightly higher in samples stored under the ambient storage. Total phenolic content was higher in beer in ambient storage, and conversely, the total flavonoids were higher in beer stored in the refrigerator. Overall, this study found that the HomChaiya rice beer is highly suitable for extended storage at low to ambient temperatures.

Keywords: Beer; HomChaiya rice; Malting; Qualities; Storage.