ABSTRACT

Some of the rural areas where rice beer is predominantly prepared were visited and the process of preparation was observed and documented. The methodologies followed by the Karbi, Deori, Ahom, Mising, Bodo, and Dimasa communities of Assam were studied. Also, the methodologies practiced by the Angami tribe of Nagaland, Khasi tribe of Meghalaya, and Adi-Galo tribe of Arunachal Pradesh, which are neighboring states, were studied for comparison. The plant species used for starter cake preparation were collected from the places visited and their taxonomical identification was carried out. The starter cakes and rice beer prepared by the various tribes were also collected.

The rice beer samples were studied for the content of organic acids, carbohydrates, and amino acids by high-performance liquid chromatography (HPLC). The aromatic compounds were detected by GC-MS method. The analysis evinced a wide variation in content of the major organic acids. Lactic acid was found in high concentration in all the samples, while the 66other organic acids were present in variable amounts. Among the carbohydrates, glucose was predominant and some other monosaccharaides were also detected. Most of the essential amino acids were found to be present, and among them, aspartic acid was the most abundant. All the samples contained the volatile or semivolatile aromatic compounds with phenyl ethyl alcohol being the most abundant compound. The overall study revealed that this form of drink has important nutritional values and dietary requirements.

A comparative study of rice beer prepared using the various starter cakes was done based on their physicochemical, biochemical, and microbiological properties. Significant variations in the density, hardness, and color of the starter cakes were found. The moisture was low in all the cakes and carbohydrate was the major component. The pH, titrable acidity, alcohol content, sugars, and starch did not vary much among the prepared rice beer. Polyphenols were present in the final product in various concentrations and the rice beers also evinced considerably high antioxidant activity. Yeasts and lactic acid bacteria were dominant in all the samples and spoilage microbes were absent. The study revealed significant variations among the starter cakes and the final product.