Abstract

India is the leading producer and importer of pulse in the world. Post-harvest loss is very high in India with losses during storage around 5 to 10%. This situation demands the development of storage guidelines for pulses to provide information to farmers on how long storage is possible without deterioration. Black gram is selected for this study as it is an important pulse used in many traditional specialty products in our country. The major storage conditions that affect any grain are temperature and moisture content. Quality parameters of black gram stored at different initial moisture contents (9, 12, 15 and 18% wet basis) at 20, 30 and 40°C were determined. The storage variables (moisture content of the sample, storage temperature and time of storage) had a negative correlation with germination and a positive correlation with fatty acid value (FAV). The maximum storability of 42 weeks with good seed viability and appreciable microbial stability was found in 9% initial moisture content black gram stored at 20°C. The 15 and 18% black gram stored at 30°C was safe up to 10 weeks hence the post harvest treatment like drying to safe moisture content can be recommended. High risk is involved in storing Black gram at higher moisture contents (15 and 18%) at high temperature of 40°C, beyond 2 to 4 weeks because of loss in seed viability and increase in FAV and the early infection with visible and invisible moulds. The safe storage guidelines chart and safe storage time model developed can be used to predict allowable safe storage time of black gram between moisture content and storage temperature ranges of 9 to 18% w.b. and 20 to 40°C, respectively.

Key words: Black gram, moisture content, storage temperature, safe storage guidelines.