Combined osmotic dehydration (sucrose solution: 50-70 % w/w, 30-50°C for 2 h followed by air drying at 40 and 60°C) is an appropriate process for preservation of oil retention capacity, lightness and yellowness of lemon peels (Citrus limon. v. lunari). Incorporation of sugars to lemon cuboids pieces increased drying rate during the first falling rate phase of the air dehydration step and improved their color stability. Osmotic dehydration process allows protective effect against further total phenol loss during air drying: significant loss of total phenol content (70-80 %) was recorded during osmotic dehydration and then it remains constant during air drying at 40 and 60°C. For the investigated temperature of osmotic pretreatment (30-50°C), water retention capacities were reduced by up to 70 % and were maintained constant during air drying.

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The physicochemical characterization and the sensory evaluation of six Tunisian dates' cultivars, preselected on the base of the D-optimal design, have been made to compare them with the principal Tunisian dates cultivar, Deglet Nour. The morphological (fresh fruit weight and pulp content) and physicochemical (quality index) studies showed a great diversity among tested cultivars. In fact, the percentage of pulp indicated the existence of cultivars as interesting as Deglet Nour (89.3 ± 0.0), such as Horra (91.9 ± 0.1) and Alig (92.3 ± 0.1). Chemical analysis showed that Mnekher had high levels of total sugars (59.2 ± 0.0 of FM) and that Angou presented the highest ash content (3.6 ± 0.0%). Also, the sensory profiling revealed that each cultivar has its own distinctive characteristics (colour, texture and taste) and that Deglet Nour, Mnekher and Alig presented a tender and soft texture unlike the others, especially the cultivar Kintichi. In addition, the results relating to the hedonic study showed that Deglet Nour,, known as "finger of light", was the most appreciated (the best preference score) followed by Alig and Mnekher, whereas, the other studied cultivars were rather rejected by the consumers, especially Horra, Kintichi, Angou and Hamra. These two sensory evaluations revealed that the Tunisian consumer is more attracted by sweet and soft cultivars.