Stevia plants are a good source of carbohydrates (61.93 % d.w.), protein (11.41 % d.w.), crude fiber (15.52 % d.w.), minerals (K, 21.15; Ca, 17.7; Na, 14.93 & Mg, 3.26 mg/100g d.w. and Cu, 0.73; Mn, 2.89; Fe, 5.89 & Zn, 1.26 mg/100g d.w.) also essential amino acids were found in amounts higher than those recommended by FAO and WHO for adults as well as non-essential amino acids. Stevioside was extracted and purified from the dried Stevia leaves by three methods. The first one, extraction by hot water (65 °C) at different ratios of leaves to water (1:15 to 1:75). The optimum ratio was 1:35 in which the maximum stevioside content was obtained (7.53 %), recovery of stevioside was 80.21 % and purity related to depigmentation was 97.56 %. The second method, extraction by methanol at ratio 4:1 methanol/leaves and purification, recovery of stevioside was 94.90 % and purity was 81.53 %. The third method, extraction by mixture of methanol/water (4:1) and purification, recovery of stevioside and purity were 92.34 and 79.81 %, respectively. Physical and chemical characteristics of the extracted stevioside were studied. Stevioside extractions were analyzed by HPLC in which the highest amount of stevioside (23.20 %) was obtained in methanol extract. Physical, chemical and organolyptic characteristics of extractions indicate that this sweetener has been applied as substitutes for sucrose in different drinks and baking products.

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139of the extracts during the storage period. Also, the addition of the extracts was significantly effective in reducing histamine, tyramine and putrescine formation during the storage period. Compared to control patties, the addition of these natural extracts was effective as antioxidant and antimicrobial agents for improving the properties of lamb patties.

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Detoxification of protein rich Jatropha kernel cake to eliminate the phorbol esters is a great challenge for its industrial utilization in food processing. Several methods either chemical or physical have been previously applied trying to degrade phorbol esters in Jatropha curcas seed cake, which are the main toxic compound with thermo-stable properties. The objective of this study was to compare the different methods to get rid of phorbol esters (PE) including, chemical treatments (0.1 M NaOH/90 % methanol, 85 % ethanol, 90 % methanol & 85 % ethanol (50:50) for 8 h), physical treatments (microwave, ultrasonic and microwave + ultrasonic) and enzymatic treatment by crude germinated Jatropha seed lipase (CGJS). The results showed that the elimination of phorbol esters content chemically treated either by 0.1 M NaOH/90 % methanol or ethanol 85% had effectively decreased by 98.04 % and 98.17 %, respectively compared to control. The treatment by methanol 90% and ethanol 85% (50:50) gave degradation percentage of 95.43% of phorbol esters. The enzymatic elimination of phorbol esters by crude germinated Jatropha seed (CGJS) lipase proved high efficiency of detoxification by reducing the percentage to 98.43%. On the other hand, physical detoxification of Jatropha seed kernel showed good results with microwave treatment by reducing phorbol esters content to 86.29 %. Treatment by ultrasound has detoxified the phorbol esters content by 87.60 % in Jatropha curcas seed. While, combination between microwave & ultrasound increased the percentage of phorbol esters degradation to 88.38 %. In conclusion, enzymatic degradation of phorbol esters is a safe method for degradation as it is both an un-expensive and easy way for detoxification.