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العنوان
EFFECT OF SOME SEED SPROUTING USING
SALINE WATER ON SPROUT QUALITY
DURING STORABILITY AFTER
TREATED BY RADIATION /
المؤلف
HEGAB, EMAD ASHOUR TOUKHY.
هيئة الاعداد
باحث / عماد عاشور طوخي حجاب
مشرف / ممدوح محمد فوزى عبدالله
مناقش / سمير كامل الصيفي
مناقش / أحمد عبدالوهاب عبدالحافظ
تاريخ النشر
2021.
عدد الصفحات
177 P. :
اللغة
الإنجليزية
الدرجة
ماجستير
التخصص
الهندسة الزراعية وعلوم المحاصيل
تاريخ الإجازة
1/1/2021
مكان الإجازة
جامعة عين شمس - كلية التمريض - قسم معهد الدراسات العليا والبحوث للزراعة في المناطق القاحلة
الفهرس
Only 14 pages are availabe for public view

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Abstract

Buds are most often consumed raw; Thus cooking is not used to prevent contamination from pathogens. Large numbers of microbes on the seeds and their sprouts are the primary factor for a short shelf life of products and the pathogens present may cause outbreaks of human diseases. Sprouts are known to have poor storage life (2-3 days) even at low temperature (4 to 8 ° C) storage.Clover (Medicago satira):
In this study, clover seeds were germinated with four treatments. T1 (ST) (Dipping in 20g/L Calcium hypochlorite for 20 min. +Washing with NaCL then, soaking in 2000 ppm NaCl, 12 hr. / 3 days), T2 (ST) (Dipping in Calcium hypochlorite for 20 min. then, washing tap water, 12 hr. / 3 days), T3 (NST) (Dipping in tap water + Washing by NaCL, 12 hr. / 3 days) and T4 (NST) (Dipping in tap water + washing by tap water, 12 hr. / 3 days).
Trail 2, treated clover seeds in T1 and T4 were low and highly contaminated with microbial load. Clover sprouts were exposed to irradiation doses at 1, 2 and 3 kGy, to study the effect of gamma radiation on quality. Main trail, T4 was modified to dipping seeds in sterilized tap water and washing by sterilized tap water, for 12 hr. /3 days. Sprouts were exposed to irradiation doses and stored at 9°C and quality parameters were evaluated during storage.
Clover sprouts can be treated with gamma radiation, a no thermal food process, to reduce microbial load and forborne pathogens and to increase shelf life. After irradiation at dose of 2 kGy, the total bacterial count decreased from 5.0x107 to 6.0x103 cfu/g, and the total coliform counts decreased from 1100 to 3 cfu/g E. coli count from 2.9x102 to  3 and Staphylococcus aureus count went down from 4.5x104 to 100 cfu/g.
These results showed clover seeds germinated in sterilized tap water and irradiated at 2 kGy improved microbial safety of clover sprouts without affecting germination, chemical and quality during storage was extended to 15 day. Irradiated buds have a similar general acceptance quality to non-irradiated ones. .
Fenugreek (Trigonella foenum –graecum):
Sprouts are consumed all over the world as a highly nutritious food. However, the germination process is completely supportive of microbial and pathogen growth.
This makes the sprouts such as fenugreek, potential sources of foodborne infections and intoxications. Microbiological analyses in all treatments (sterilized and non sterilized) showed substantial microbial loads of log total bacterial counts ranged from 5.26-7.81 cfu/g, log total mold and yeast count 2.64-5.51 cfu/g. Total coliforms around 1.44-2.32 MPN/g. E. coli ranged from 1.04-1.96 MPN/g. Staphylococcus aureus was detected in all treatments sterilizes and non-sterilized it was present in relatively high density. Staphylococcus species showed positive coagulopathy and lactase reactions indicating S. aureus contamination. The fenugreek sprouts were negative for Salmonella sp. in all treatments.
To address these concerns, a combination treatment has been developed including sterilization (Hypo + NaCl, Hypo + H2O) and non-sterile (NaCl, H2O) and gamma irradiation (post germination and packing for storage) that ensures the microbial integrity of the sprouts and extends the shelf life of up to 12 days for fenugreek buds. At 9 ± 1°C. The irradiated fenugreek buds at 2 and 3 kg were staphylococcus-free. aureus throughout 12 days of storage.
However, during post-irradiation storage at 9 ±1°C, we can concluded that radiation treatment fenugreek sprouts with 3 kGy caused reduction of TBC counts , mold and yeast counts by 6.79 and 1.57 log cfu/g, respectively. Total coliform and E. coli, log counts were  0.48 MPN/g during the storage period for all treatments at dose 3 kGy. Staphylococci sp. was stay negative in all treatments.
The physical, chemical, nutritional and sensory properties have been found to be well preserved during storage. It is clear that the values of vitamin C ranged from 1.95 to 2.44 mg/100g in control samples. After 12 days, vitamin C ranged from 1.15-1.74 mg/100g in four treatments. During storage of fenugreek sprouts at dose 2, 3 kGy in sterilized treatment 2 the total phenolic (Anti-nutritional factors) significantly decreased to 8.05, 8.69 g/100g, respectively.
A qualified test panel member was unable to differentiate the irradiated samples. A dose of 2, 3 kg did not alter sensory properties and was sensually acceptable. The combination treatment developed can be an effective commercial strategy to ensure safety and thus enhance greater marketability.
Faba bean (Vicia faba)
Total aerobic plate log counts of faba bean sprouts were about 6.65-6.87 cfu/g already at the beginning of the shelf-life in all treatments. Mold and yeast also present on all type of treatments sprouts were ranged from 4.32 to 5.74 cfu/g. While total coliform and E. coli were found in wider range (3.04-2.17 MPN/g).
During 14 days of storage at 9 ±1°C, there was a gradual increase in total platelet count (TBC) with increasing storage period in all types of aseptic and non-sterile treatments. TBC numbers from bean sprouts can grow up to 6.96 logarithms / g in aseptic treatment 1.
Irradiation with 1 kGy reduced the number of total coliform by 1.08 log-cycles in sterilized treatment 2 (hypo+ H2O). E. coli were relatively low resistant to irradiation, 2 kGy dose reduced their number with max. 2.54 log-cycle in sterilizes treatment 1 (hypo+ NaCl).
Percentage of Yield ratio in faba bean sprouts ranged from 2.44 - 2.65% in various treatments sterilized and non-sterilized. After irradiation, there was a progressive decrease in the sprout length with increasing irradiation dose up to 3 kGy in treatment 2 (Hypo + H2O). Bud length under different treatments ranged from 11.75 - 24.21 mm in control bud samples. There was a significant difference in the decrease of bud length under different treatments, with the exception of treatment 4 (non-sterile, H2O) where increased growth was observed during increased irradiation doses.
The content of ascorbic acid decreased in the irradiated bean sprouts with an increase in the radiation dose compared to the non-irradiated ones. Moreover, the loss of ascorbic acid was higher in shoots grown from 3 kg than those grown from 1 kg. The loss in vitamin C content was 20.59-24.48 mg/100 g in irradiated samples at 3 kg in treatments.
The total phenolic content increased to 3.42-5.21 mg/g in the sample irradiated with 3 kGy, representing a 16.67 and 39.88% increase over non-irradiation sample, respectively.
Antioxidant activity (DPPH free radical scavenging activity) in faba bean sprouts were found to be ranged from 9.45-11.55 % in control combination treatments samples.
The panelists were not able to distinguish between non irradiated faba bean sprout and those that had received up to 3 kGy at zero time.
At day 12 of storage, the overall appearance scores of unirradiated faba bean sprout decreased from 9.0 at zero time to (range 2-4.5) in all treatments indicating that these samples were sensorially rejected.
The shelf- life of the faba bean sprouts irradiated to 2 kGy was extended. The overall acceptability scores decreased from 9.0 to 8.1 and 7.8, in treatment 1,3 (Hypo +NaCl and NaCl ), respectively. At day 12 indicating that sterilized samples were sensorially accepted.
The results of the present study showed that washing the seeds of the combined treatments with tap water during germination treatment provides adequate nutrients for the growth of buds and microorganisms. Moreover, this study showed that sprouts contain a large number of microorganisms that are difficult to reduce using washing treatments.
The irradiation of seeds used for germination has limited value due to its negative effect on germination and yield. Supporting the use of gamma irradiation with 2 kg may be the solution to reduce final numbers of encapsulation buds to levels below 3 logarithms cfu/g in Staphylococcus sp., total coliforms, E. cloi in alfalfa sprouts, fenugreek and beans during cold storage.
The synthesis process that extended the shelf life of cloves was improved by 21 days, 12 days for fenugreek and 14 days for bean sprouts at storage of 9 ± 1 °C without affecting efficacy. The collection process ensured microbiological safety. However, bud irradiation is promising. The irradiation process will not only reduce human pathogens on the buds, but also increase the keeping quality.