Osmotic dehydration of uniformly sized peas at 30C was studied using different solutions of sucrose, sodium citrate and sucrose+citrate mixture. The influence of various factors such as solution concentration and composition and the effect of agitation on the mass transfer mechanism was investigated. It was shown that the rate of water loss in the sample was increased by increasing concentration of osmosis solution and agitation. The most effective osmotic dehydration was obtained in sucrose+citrate mixed solutions of 60% total solids level for which a dehydration model was proposed. The apparent diffusion coefficient of water Da was determined using the dehydration model. The values of Da were found to be in the range 9.10 ± 10−11‐7.63 ± 10−10 m2/s.

The effect of osmotic dehydration on subsequent air drying behavior and product quality was investigated for peas being osmosed in sucrose and sucrose+citrate mixed solutions. Compared to nonosmosed samples, osmosed samples gave much higher drying rate. It was found that initial osmotic step shortened the air drying time by 55–70%, depending on the osmosis solution and process conditions. It was shown that by initial osmotic dehydration especially in sucrose+citrate solution, a product with higher allowable moisture content and increased solid density can be obtained and rehydration characteristics of osmosed samples are improved. In addition, product thus obtained had a more attractive color and standard level of organoleptic acceptability.

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The effects of deodorization time and temperature on the physical and chemical properties of cottonseed oil were investigated. Higher temperatures and longer times lead to increases in free fatty acids, peroxide value, viscosity and refractive index while iodine value, unsaponifiable matter and induction period decreased.

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