الفهرس 
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Abstract
Egypt comes into the top five pumpkin producing countries in the world. So, Four Egyptian pumpkin (Cucurbita moschata) cultivars namely: Qina, Edwa, Kafr-Saad and Kafr-El-Batikh were used in this study. The objectives of the study were to evaluation the physical properties of the fruits, gross chemical composition and mineral contents of fruits and seeds as well as estimation of beta carotene and vitamin C contents in pumpkin fruits. Also, the study aimed to determination of some physicochemical properties, fatty acid composition, phenolic compounds and total tocopherols of pumpkin seed oils. In addition, the study was addressed to preparation and evaluation the pumpkin flour, pumpkin marmalade as well as addition of pumpkin pulp by 10, 20, 30% instead of apricots for manufacturing of Qamar El-Din sheets product.
The obtained results cold be summarized as following:
Pumpkin fruits:
• The fruits of the studied cultivars had different morphological shapes with weight ranged between 4.18 to 6.36 kg per fruit.
• The pulp, peel and seeds constituted 70.10-71.53, 26.49-27.99 and 0.27-1.67% of the fruits weight; respectively.
• There were significant differences between the studied cultivars in their contents of seeds.
• Gross chemical composition analysis for pumpkin fruits indicated that, the moisture content ranged from 91.33 to 94.88%, crude protein from 0.60 to 1.35%, crude fat from 0.14 to 0.15%, crude fibers from 0.35 to 0.55%, ash from 0.45 to 0.90% and carbohydrates 3.59 to 5.68 (on wet weight basis).
• Pumpkin fruits consider a low calories food and caloric value ranged from 18.11 to 29.47 Kcal/100g of fresh fruit.
• Minerals content studying indicated that, all studied cultivars fruits were rich in their content of potassium (K) element which was ranged from 2300 to 2450 mg/100g (on dry weight basis) while, cadmium (Cd)element was absent in all studied pumpkin fruits.
• Beta-carotene content ranged from 18 to 106 mg/100g (on dry weight basis) in the studied pumpkin fruits. The highest value was recorded for Qina cultivar fruits and the lowest value for Kafr-El-Batikh cultivar fruits while, Edwa and Kafr-Saad cultivars fruits recorded 64 and 82.80 mg/100g (on dry weight basis) of β-carotene; respectively.
• The studied pumpkin fruits contained ascorbic acid as 2.30, 3.90, 21.81 and 29.70 mg/100g (on wet weight) of Edwa, Kafr-El-Batikh, Qina and Kafr-Saad; respectively.
Pumpkin seeds:
• Pumpkin seeds consider a good source of protein which ranged from 30.27 to 31.10% and oil which ranged from 33.68 to 36.43% (on wet weight basis).
• The low moisture content level (6.43-7.20) of pumpkin seeds might be an advantage in terms of its shelf life.
• Pumpkin seeds recorded high caloric values ranged from 445.72 to 467.30 Kcal/100g
• Relatively high levels of phosphorus, magnesium, calcium, iron and zinc were recorded in pumpkin seeds among the studied minerals.
Pumpkin seeds oils:
• Studying some physicochemical properties of pumpkin seeds oils indicated that, the refractive index ranged from 1.4672 to 1.4676,the acid value ranged from 0.59 to 0.99 (mg KOH /g oil), the peroxide value ranged from 2.99 to 3.09 (meq/kg oil), saponification number ranged from 182.20 to 186.30 (mg KOH/g oil) and the iodine value ranged from 80.41 to 81.80 g I2/100g oil.
• The determined physicochemical properties of pumpkin seeds oils demonstrated that, pumpkin seed oil is a good candidate for use as an edible oil.
• Using Thin Layer Chromatography technique (TLC), the total lipids of pumpkin seed oils were fractionated to eight fractions namely: polar lipids, monoglycerides, 1,2 & 2,3 diglycerides, 1,3 diglycerides, sterols, free fatty acids, triglycerides and sterol ester & hydrocarbons as well as two unknown fractions.
• The major lipid component was the triglycerides which constituted from 69.09 to 80.31 of the total lipids, while polar lipids constituted the minor proportion (0.89 to 1.41% of total lipids) in pumpkin seeds oils.
• The fatty acids of pumpkin seed oils consisted mainly of four fatty acids namely: oleic, linoleic, palmitic and stearic.
• Oleic acid was the predominant fatty acid in seed oils of Edwa, Kafr-Saad and Kafr-El-Batikh cultivars and ranged from 38.00 to 46.04% of the total fatty acids, whereas linoleic acid was the major fatty acid in Qina seeds oil (35.17% of the total fatty acids).
• Linoleic fatty acid constituted from 26.21 to 35.17% of the total fatty acids of the studied pumpkin seeds oils, therefore, pumpkin seeds oil can be a good nutritional supplement as a source of the essential linoleic acid.
• The total unsaturated fatty acids in pumpkin seeds oils ranged from 70.69 to 73.30% and consisted mainly of oleic and linoleic acids, while the total saturated fatty acids ranged from 26.66 to 27.96% and consisted mainly of palmitic acid (16.02 to 17.17%) and stearic acid (8.97 to 10.50% of total fatty acids).
• Tocopherol contents of the studied pumpkin seeds oils were 98, 67, 158 and 111 mg/100g oil for Qina, Edwa, Kafr-Saad and Kafr-El-Batikh; respectively.
• The total phenolic compounds contents in the studied pumpkin seed oils were 6.86, 35.20, 55.34 and 0.27mg/kg oil for Qina, Edwa, Kafr-Saad and Kafr-El-Batikh; respectively.
Pumpkin products:
(a) pumpkin flour
• The dehydration ratio of the prepared pumpkin flour were ranged from 12.10:1in Kafr-El-Batikh pumpkin cultivar to 21.63:1 in Kafr-Saad cultivar, while intermediate ratio (about 15:1) was recorded for Qina and Edwa cultivars.
• The prepared pumpkin flour contained 11.40-11.70% moisture, 1.57-2.30% crude fat, 10.88-14.90% protein, 7.95-8.61% crude fibers, 7,84-8.66% ash and 55.12-58.24% carbohydrate.
• The high ash and crude fiber contents in pumpkin flour could be make it a good complement for wheat flour as well as a source of β-carotene and yellow color supplement in bakery products.
(b) Pumpkin marmalade
The high scores for all sensory parameters of the prepared pumpkin marmalade compared to the commercial orange marmalade (control) could be encourage to use this important crop for producing marmalade, jams and preserves as a good application.
(c) Qamar El-Din sheets product
Sensory evaluation of the prepared Qamar El-Din sheets with no signification differences in taste and flavor until 10% addition of pumpkin pulp instead of apricot fruits indicated that, by this application may be produce Qamar El-Din product (a famous product in Arabic countries) with lower price as well as find another new use for pumpkin fruits.
Conclusion
• from the obtained data, it could be concluded that, pumpkin fruits contained a considerable amounts of potassium, β-carotene as well as ascorbic acid with low caloric value.
• Pumpkin seeds could be a good source of protein and edible oil with high content of essential linoleic acid as well as vitamin E.
• Pumpkin fruits could be successfully used for preparation of some technological products such as pumpkin flour, pumpkin marmalade and its addition to apricot fruits for manufacturing the Qamar El-Din sheets product.