الفهرس 
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Abstract
Our interests in this study were directed to the importance of different heat treatments (blanching –Steaming and microwave then freeze storage) for selected vegetable varieties (green beans) –Broccoli – cabbage – Cauliflower and fruits (peach-kiwi-papaya -guava), and the extent of the effect of these treatments on the nutritional value (moistures –ash–dissolved solids) and the content of phytochemicals (vitamin C–total phenols–total flavonoids–antioxidant activity) and sensory characteristics (texture and color). The study showed the following results:
1. The effect of blanching:
moisture contents of vegetables increased were ( (green beans (84.44%–85.82%) Broccoli (88.82% - 91.43%) Cabbage (92.83% - 94.73%) and Cauliflower (91.99% - 93.37%)
ash content for vegetables were Decreased, as Green beans from (7.48-9.91%), Broccoli (8.96-6.65%) Cauliflower (7.28-11.63%)and Cabbage (6.34-8.15%)
Total soluble solids values for vegetables samples were decreased in green beans from (7.16-10.33%), Broccoli (9.17-10.66%)-cauliflower (7.83% -6.00) and cabbage was (7.00-6.00%).
also it was pointed decreased in vitamin C (green beans 86.12-56.70) broccoli (551.14 -436.87) cauliflower (460.66-296.23) cabbage (428.97-213.47) mg / 100 g DW.
Total phenols contents were decreased in Green beans ranged (506.48-436.57), broccoli (1533.27-1333.56) but increased in (cauliflower 832.29-1077.36) and cabbage (796.97- 985.75) mg / 100g DW.
Flavonoids content has dropped its values in green beans ,broccoli and cabbage) were (11.84-15.72), (26.19-26.26) and (23.40-25.92), respectively, but increase in cauliflower (18.15-24.60) mg /100g DW
Antioxidant activity values decreased in all samples of vegetables.
2. The Effect of steaming :
A slight deficiency occurred in moistures values for (Green beans - cabbage - peach - kiwi - guava - papaya) (83.14%, 91.59%, 87.34%, 84.81%, 85.74%, and 90.19%), respectively. But decreased in broccoli (89.04%) and cauliflower (92.86%)
values of Ash , soluble solids and vitamin C for all vegetables and fruits were decreased except Guava was slight decrease.
Total phenols contents have increased in Green beans, broccoli, Cabbage, cauliflower and guava (536.63, 1795.89, 894.33, 1133.78, and 5298.46), respectively .while decreased in kiwi (1222.61)-Peaches (1428.18), and papaya (1747.49) mg/ 100 g DW.
The total flavonoids contents were increased in Broccoli - cauliflower – and but decreased fell in the rest of samples.
DROP occurred in Antioxidant activity For all samples except green beans, it was stable
3. The effect of microwave treatment:
The moisture values were decreased in All vegetables and fruits , (green beans 84.38%), (broccoli 88.78%), (cauliflower 91.69%), (peaches 87.31%), (kiwi 85.44%), papaya (89.98%) and (guava 86.24%) except cabbage, have increased (93.78) %.
Slight decreased in ash contents as well as total solids for all samples.
all vegetables and fruits have Gradually decreased in vitamin C as (Broccoli, green beans, cauliflower, cabbage, peaches, kiwi, papaya, guava were (507.21, 68.63, 375.45, 334.85, 55.16, 376.85, 459.08, 813.45) mg/100 g dry weight, respectively. The results indicated that the best Treatment was microwaved.
The total phenols contents were increased in green beans was ( 518.26), broccoli (1655.21) ,cauliflower (1661.79) ,cabbage (987.76), peach (1500.95) and guava (6.333.06) except papaya (2138.58) And kiwi(1504.45) have decreased mg/100g dry weight .
Gradually increased Flavonoids value for all samples broccoli (28.93)–cauliflower (20.01)–peach (38.05) and decreased in green beans (14.15), cabbage (22.66) , papaya( 21.44), kiwi (11.20) , guava (13.91) mg / 100 g dry weight
A slight increase in the antioxidant activity of all samples (green beans, peach and Guava) were (31.98%, 73.37%, 96.14% )respectively. While decreased in broccoli, cabbage, cauliflower, papaya, and kiwi. (44.34%, 26.25%, 48.57%, 51.50%, 61.24%), respectively.
4. Freezing storage (Fresh-blanching-Steam - microwave).
During storage period for all treatments, as well as fresh ones, the values of moisture, ash, total soluble solids and vitamin C decreased for all samples.
Total phenol contents were decreased gradually over the storage period in (Green beans - broccoli - cabbage - kiwi – papaya- cauliflower )–(cauliflower except for boiling in water, were in a slight increase compared to other treatment) and increased in (guava and peach)
An increasing in the flavonoid values in (cauliflower and peach), while these values decreased in (Broccoli - green beans - cabbage-Papaya- kiwi - guava)
Antioxidant activity increased of peach and papaya samples and firmness the value in guava and a gradual decreased in the rest of the varieties.
5. Sensory properties were evaluated in (fresh, blanching , steam, microwave) and found that:
The texture of all fresh samples were having a higher and this values were decreased after exposure to all treatments to the degree which acceptable to the consumer also gradually decreased during storage period and the best treatment was steam followed by microwave according to each samples .
The color in relation of all varieties was excellent in fresh, and the degree have increased when treating the varieties by blanching followed by microwave then steam in relation to the vegetables. While for the color in the fruits, were have a higher degree in microwave treatment the microwave was better and gradually decreased during the storage period.
This study proved that the best treatment to preserving nutritional values and antioxidants (microwave followed by steam)