Influence of Osmo-mechanical dehydration on the quality of ber

Present investigation was carried out to develop intermediate moisture shelf stable product, by osmo-mechanical dehydration process. The effect of different parameters viz. harvesting stage, pricking, chemical treatment, osmosis and drying air temperatures was observed on the quality of dried product like solid gain (i.e. sugar gain), water loss during osmosis, rehydration characteristics, water activity, colour and sensory characteristics. It was observed that pricking and chemical treatment resulted in maximum removal of moisture and solid gain during osmosis. The moisture reduction was upto 52.8 - 59.1% and solid gain was 16.3 - 18.0% (control treatment had actually leaching of sugar). The chemical treatment was more effective in non-pricked samples and vice versa. The coefficient of rehydration and rehydration ratio both increased. The osmotic dehydration enhanced the sensory qualities and shelf life of the product by lowering water activity from 0.8 to between 0.4 - 0.6. Harvesting at stage II (turning stage) helped in retaining light brown colour product due to more yellowness It was concluded that drying ber at 55°C, treated and pricked, harvested at stage II resulted in a good quality intermediate moisture and shelf stable dried product.