الفهرس 
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Abstract
Potato is considered to be an important crop and it plays an important role in the diet of the majority of people in the world. It is consumed by different forms of processing into a variety of products. Frying is one of the oldest cooking methods widely used to prepare the tasty and crispy foods. Also, oil uptake is one of the most important quality parameters of fried food which is compatible with recent consumer trends towards healthier food and low fat products.
This study was carried out to reduce the oil uptake and improve sensorial quality during deep-frying.
The obtained results are consistent with the following specific conclusions:
1. The results showed that increasing the frying temperature from 160 to 180°C, decreased the amount of oil uptake of potato strips. Also, the amount of oil uptake increased by increasing the frying time from 2to 5 min for potato strips. The best frying conditions was found to be 180 °C for 5 min. At these conditions the average of oil absorption was 28.48% in the case of potato strips and reached 49.30 % in the case of potato chips.
2. The results revealed that the oil content of potato strips and chips increased with increase in frying cycle for all samples. This could be due to the increase in degradation products and viscosity of the frying medium as a result of thermal polymerization or oxidative deterioration during cooling. There was no significant difference (p < 0.05) between oil uptake of fried samples after 1st, 10th and 20thfrying cycle.
3. The (soaking in 2% chitosan (CH), 2% carboxy -methylcellulose (CMC) , 0.1% sodium metabisulphite and mixture of them (1:1:1)) on water content, oil uptake, sensory evaluation and color of fried potatoes (strips from white potato variety (Accent) and chips from red potato variety (kara), was investigated. Untreated samples were used as control.
Compared to the control a moisture reduction of 12.99% and 13.41% from the products was recorded for fried samples of the water blanched potato strips and chips, respectively (p<0.05). Similarly, a reduction of 21.85% and 28.01% in oil uptake was recorded for the fried water blanched potato strips and chips respectively (p<0.05). Whereas the most effective pretreatments that reduced the oil uptake by 42.54% and 40.04% for fried potato strips were blanching followed by CMC treatment (T7) and blanching followed by treatment with mixture of CH, CMC and sodium metabisulphite (T9).
Oil uptake reduction reached 58.02% and 57.24% for fried potato chips that treated with T17 and T19, respectively.
Sensory evaluation showed that the water blanched and the blanched followed by CMC treated potato chips and strips had high scores compared with the control samples.
4. The oil content of fried potato strips was significantly decreased with water blanching and blanching followed by chemical pretreatment as compared to control. The present data showed that blanching process decreased the oil uptake. The percent of oil content was 22.01% in the case of fried potatoes pretreated with steam blanching compared to 29.15% in the control samples.
5. The osmotic pretreatments decreased the oil uptake for the two forms of potato (strips and chips). The lowest values were 49.39% and 68.03% for strips and chips potato, respectively.
Generally, the present data showed that blanching, followed by osmotic dehydration (10% salt) and 2% CMC coating pretreatment recorded the best results for color, flavor, texture and overall acceptability indicating that this treatment was the most suitable for potatoes fried product.