الفهرس 
ContentsOnly 14 pages are availabe for public view
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Abstract
In recent years, the physiological functionality of fruits and vegetables has received much attention due to the increasing interest in human health. The protection provided against degenerative and chronic diseases, such as cancer and cardiovascular diseases, by fruits and vegetables has been attributed to the fact that these foods may provide an optimal mix of phytochemicals. These phytochemicals are natural antioxidants (mainly vitamin C, vitamin E, carotenoids and flavonoids), fibre and other bioactive compounds. Many beneficial plant species have been underused or haven’t been developed to their full potential, although they may possess high nutritional value, they have been overlooked by many researchers. Goldenberry, (Physalis peruviana L.) which is native to South America, is one of the overlooked beneficial plant species. Though, it tolerates poor soil and the yields are high, it has nowhere become a major crop. This may be related to the fact that few researches have been carried out on goldenberry regarding its culture, chemical composition, properties and industrial utilization. In Egypt, the goldenberry, fruits are casually eaten and occasionally sold in markets, but the plant is still not an important crop. It is commonly grown but on a lesser scale or interplanted with other crops. This study has been carried out to evaluate the complete chemical analysis of goldenberry, its nutritive value including ?-carotene, ascorbic acid and minerals. In addition to identifying its volatile compounds, as well as their concentrations. Moreover, its antioxidant activity was also evaluated which would become a valuable tool in promoting the goldenberry. Processing of goldenberry into jam, juice and compote was also a purpose of this study, as the season during which fresh goldenberries are available in Egypt is short, lasting from late October to March. Therefore processing acceptable products extends the period of availability of the fruit in a preserved form. However, processing may change the concentration of some bioactive compounds. So, estimation of the chemical composition, ?-carotene content and antioxidant activity of the products was also carried out in this study. Finally, the organoleptic properties of the processed goldenberry products were evaluated by 16 panelists to determine their acceptability. The results of the present study can be summarized as follows: 1- The protein content is exceptionally high for a fruit which might be related to the high number of seeds present in the fruit. 2- There is no significant difference noticed when comparing the moisture, total soluble solids, fat, total sugars (reducing and non-reducing sugars) crude fibres and ash contents of goldenberry with those of some other common fruits and vegetables. 3- The total titratable acidity of goldenberry was high. This is obvious when comparing with other common fruits but still it is much lower than that of lemon. 4- Goldenberry contains moderate amount of ascorbic acid, which was higher than that of apple, apricot, mango, peach and raspberry and lower than that of grape, lemon, orange and strawberry. 5- The content of ?-carotene of goldenberry indicates that it can supply the body with the needed average daily intake of ?-carotene, consequently it is an excellent source of ?-carotene. 6- Goldenberries possess a high amount of potassium, higher than some other common fruits and vegetables. In addition, zinc and copper content were also higher than those of some fruits and vegetables. While iron and calcium are found in moderate amounts in goldenberry. 7- Separation of the volatile compounds of fresh goldenberry utilizing a non polar column trapped many volatile compounds than when utilizing a polar column. In other words, the non polar column was more efficient quantitatively than the polar one in the separation of the volatile compounds of fresh goldenberry. 8- The most quantitatively abundant volatile compound, separated using a polar column, was benzene followed by toluene. 9- 13-tetradecenal, 9-octadecenoic acid, hexadecanoic acid and butylated hydroxytoluene are the most abundant identified compounds separated on a non polar column. 10- The viscosity of goldenberry jam was much higher than that of juice and preserved goldenberry (compote), which is a desirable characteristic of the product. 11- The fibre content of goldenberry jam and preserved goldenberry (compote) decreased than that of fresh goldenberry while no fibre was detected in goldenberry juice. 12- pH of goldenberry products was acidic which is important for food stability and preservation. 13- The acidity of the goldenberry jam and preserved goldenberry (compote) decreased to be much lower than that of fresh while that of juice has slightly decreased. 14- The ascorbic acid content of all the goldenberry products decreased than that of fresh goldenberry.