الفهرس 
IntroductionOnly 14 pages are availabe for public view
Abstract
Fruits and vegetables are vitally important as nutrient-dense food for human health. Every year, mechanical, microbiological, and physiological impairments result in close to 20–40% postharvest losses of crop harvests. So, several tactics and postharvest technologies are employed to reduce these losses and have been developed to cope with variation between crops. The changes in some physiological and biochemical aspects associated with the postharvest of potato and grapes with and without treatments have been investigated.
The main experimental results can be briefly summarized in the following:
Firstly: applying anti-sprouting technique
1- During storage period, sprouting percentage and sprout length increased in untreated-tubers stored at 30°C at the beginning of 4th week followed by those stored at 20°C, while potato tubers treated with rosemary essential oil and/or coriander at the same temperature delayed sprouting till the 8th week of storage along with limited elongation of sprouts.
2- Weight loss increased in untreated-tubers stored at 30°C accompanied by sprouting. However, rosemary essential oil and coriander treatments significantly decreased the wight loss and the lowest weight loss has been detected in rosemary-treated tubers stored at 20°C followed by those stored at 30°C.
3- Accumulation of soluble sugars in untreated tubers concomitant with starch degradation during storage in untreated tubers at 30°C but was significantly decreased by the treatment with rosemary essential oil and coriander extracts at the same temperature.
4- The decline in contents of free amino acid from the 6th week along with gradual increases of total soluble protein and proline was detected in untreated potatoes until the end of storage at both storage temperatures. While the rosemary and coriander-treated potatoes exhibited significant retention of amino acid and soluble protein as well as proline levels particularly that stored at 20°C.
5- Accumulation of MDA and H₂O₂ levels in untreated tubers stored at 30⁰C followed by those stored at 20⁰C. However, coriander and rosemary treatments significantly reduced the levels of both, particularly, those stored at 20⁰C.
8- Time progression of storage resulted in decline in FRAP and DPPH antioxidant capacity concomitant with reductions in AsA, TPC, and TFC contents of untreated potato tubers stored at both studied storage temperatures (20⁰C and 30⁰C). Nevertheless, exposure of potato tubers to rosemary and/or coriander extract retarded such reductions at the same temperatures.
9- The enhancement of CAT, APX, POD, PPO and ASO activities was associated with time progression of storage in untreated potato tubers at both storage temperatures. However, rosemary and /or coriander treated tubers exhibited lesser activities of such enzymes by ending of storage period, particularly for those stored at 20°C.
Finally, it is worthy to conclude that, rosemary was better antispouting agent than coriander at 20°C for storing potatoes due to minimal sprouting, lesser accumulation of sugars and lower level of lipid peroxidation resulting in better quality tubers after prolonged storage for 12 weeks postharvest.
Secondly: applying edible coating technique
1- The appearance of good grapes decreased with the prolongation of storage time. However, GA-coated grapes were darker, shinier and shrink less than untreated ones.
2- The increments in weight loss throughout the cold storage period were significantly higher in control fruits. WhereasGA- coated fruit exhibited a comparatively lower rate of weight loss throughout the storage period.
3- Increased TSS along with decreased TA of untreated grapes fruits with the progression of storage period. However, GA treatments significantly retarded the increments of TSS as well as retained higher TA corresponding with the reduced pH values of coated- grapes particularly at 5%.
4- Gradual decline was observed in either AsA or TPC contents along with reduction in DPPH levels of untreated grapes throughout the cold storage period. However, 5% GA-coated grapes maintained antioxidant capacity during storage, concomitant with their retention to AsA and TPC contents.
5- All the individual tested phenolic acids decreased sharply at the 20th day of storage period as compared to zero day. Nevertheless, 5% GA-treated grapes displayed higher phenolic acids content in comparison to other concentrations.
6- Progressive time of storage induced gradual increase in anthocyanin content and the activities of POD and CAT of untreated grapes, whereas GA treatment induced further increase in such parameters for coated ones, particularly at 5% during the cold storage.
In brief, GA, particularly at the 5% is a good commercial postharvest edible coating to preserve both nutritional and antioxidant values of ‘Flame Seedless’ grapevine fruit up to 30 days of cold storage at 4 ± 1°C with 90 ± 2% RH.