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In this study, the optimum combination of major factors affecting the acceptability of whey-based Ricotta cheese i.e. fat at three levels (0, 5, 10%), salt at three levels (0, 1, 2%), and starter culture at two levels (0, 3%) was determined in a complete randomized design method with a factorial experiment. Ricotta cheese trials made by mixing whey and milk in a ratio of 5:1 were then organoleptically judged on the basis of the main attributes such as color, flavor, texture, and overall acceptability. The collected data were then statistically analyzed using a seven point hedonic method. The results show that the addition of fat had a significant effect on all sensory attributes (p< 0.05). The incorporation of salt in the formulation also had a significant effect on flavor, color, and overall acceptability (p< 0.05) as well as on texture (p< 0.01), whereas the addition of starter culture had a significant effect only on texture (p< 0.01) and overall acceptability (p< 0.05). It was concluded that a combination of 5% fat, 2% salt, and 3% starter culture gains a higher score and could be recommended as the preferred formulation for Iranian consumers.

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In this study response surface modeling was performed by using experimental datachr('39')s obtained from the amount of samples weigh, moisture content and the Brix of produced samples after different condition of osmotic dehydration process including: different concentration (0-60 %w/w) of sucrose solution with different temperature (45-55 ⁰C) and different processing time (60-180 minutes). Results showed that osmotic solution concentration and temperature and duration of osmotic process had significant effect on the amount of moisture content, Brix, the weight of sample after osmotic process and sensory attributes of final product. The highest amount of Brix (39.69%) was observed in the dried samples in osmotic solution with 60% concentration for 180 minutes, while the lowest amount of brix was related to osmotic processing time of 60 minutes and solution temperature of 45 ° C, which shows the significant effect of osmotic solution concentration and osmotic processing temperature and time on the brix changes of samples. Results of the sensory evaluation showed that, the highest amount of texture (8.85) and color (8.46) desirability score were observed in the osmotic processing time and temperature range from 45-52.5 ° C for 160-85 minutes. The amount of texture and color desirability score of the samples decreased by increasing osmotic processing time and temperature. The higher osmotic solution concentration and the lower osmotic processing time and temperature lead to the better color and texture of the samples. Osmotic dehydration improved different quality attributes (color, taste and texture) of final product compared with blank samples. Increase of samples Brix during osmotic dehydration process, indicates an increase in the transfer of sugar molecules into the samples tissue. Therefore, in sensory evaluation, the amount of taste sensory score increased with increasing osmotic processing time and temperature and osmotic solution concentration.