الفهرس 
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Abstract
I- Quality evaluation of frozen and fresh quail carcases:
A total of 50 frozen as well as 50 freshly processed quail carcases either prepared at poulterer’s shops or at home were collected from Assiut supermarkets and farms and monitored for their quality attributes.
Although all frozen quail carcases showed some deviations in the physical characters as the dark sunken eyes, flesh not give evenly on pressing in addition to the blakish discolourtion in the region of the vent in two carcases only which may be due to the effect of freezing storage, the carcases were accepted. Furthermore, all the examined fresh quail carcases either poulterer or home processed were organoleptically accepted.
The mean pH values of the examined frozen, fresh, poulterer processed and home processed quail carcases were 6.04 0.04, 5.61 0.04, 5.69 0.05 and 5.50 0.05, respectively while mean values of the cooking loss percentages were 41 0.17, 41.44 0.17, 41.3 0.25 and 41.65 0.22, respectively.
A significant difference in the pH values was observed between the different types of the examined quail carcases whereas a non significant difference in the cooking loss percentages was noticed between all types of the examined quail carcases.
Regarding the microbiological status of the examined quail carcases, the mean aerobic plate count (APC) values of the examined frozen, fresh, poulterer processed and home processed carcases were 6.12x103 2.97, 4.82 x 103 2.55, 5.75 x 103 3.16 and 3.44 x 103 1.51 cfu/g, respectively. Only two frozen carcases showed APC greater than 104/g. A significant difference in the acrobic plate count could be detected between frozen and fresh, home processed and each of frozen and poulterer processed quail carcases. On the other hand, the mean psychrotrophic count value of the examined frozen carcases was 2.3 x 103 2.39 cfu/g.
Enterobacteriaceae were existed in variable numbers in the examined quail carcases. The mean counts were 1.49x103 0.62, 1.22 x 103 0.79, 1.32 x 103 1.07 and 1.07 x 103 1.08 cfu/g of the examined frozen, fresh, poulterer processed and home processed quail carcases, respectively. Most of the examined samples had Enterobacteriaceae count within the range 103 to < 104/g.
A significant difference in the Enterobacteriaceae count was noticed between frozen and fresh as well as between frozen and home processed quail carcases.
As for coliforms, 16, 30 and 65% of the examined frozen, poulterer processed and home processed quail carcases had non detectable levels (<3 / g) whereas the remainder of the examined quail carcases were contaminated with such organisms in levels varied from 10 to < 102 /g. The detectable level of faecal coliforms ( 3 -< 10/g) was encountered in 16, 20 and 10% of the aforementioned quail carcases respectively. Only frozen quail carcases proved to harbour E.coli where 16% of such carcases contained the organism in a level of 3 to < 10/g. No significant variations in the coliform count of all the examined quail carcases could be detected.
Concerning Staph aureus count, most of the examined quail carcases (94% frozen, 90% poulterer processed and 100% home processed) showed non detectable levels (<100 / g). Only one sample each from frozen and poulterer processed carcases had Staph sureus count within the range 103-<104/g. Furthermore, Clostridium perfringens could be detected in 4 and 10% of the examined frozen and poulterer processed quail carcases where the levels of contamination were from 102 to < 103 and from 10 to <102/ g, respectively.
A total of 75, 36 and 20 bacterial isolates were recovered from the examined frozen, poulterer processed and home processed quail carcases respectively. The identified microorganisms were Clostridium perfringens, members of Enterobacteriaceae, Listeria monocytogenes, Staph aureus and Yersinia spp.
Members of Enterobacteriaceae recovered from the examined frozen and fresh quail carcases in variant percentages were Citrobacter freundi, Enterobacter aerogenes, E.cloacae, E.intermedius, E.coli, Morganella morganii, Proteus mirabilis, Providencia alcalifaciens, P.rettgeri and P.stuartii.
Neither salmonellae nor campylobacters could be detected in any of the examined quail carcases. However, the public health significance of the isolated microorganisms was discussed and suggestive measures to produce high quality quail carcases and protect the consumer were outlined.
II- Decontamination of quail carcases by organic acids and sorbate:
A total of 45 quail carcases were divided into 9 gropus, each consisted of 5 carcases. In each group, each carcase was split into two halves. Batches of 5 quail carcases halves were used as control while the other halves were dipped for one minute in acetic acid (0.5, 1 and 1.5%), lactic acid (0.5, 1, 1.5) and potassium sorbate (1, 3 and 5%). The microbiological picture for each group was determined.
Low concentrations of acetic acid (0.5%) had no bactericidal effect on the aerobic plate count, Enterobacteriaceae, coliform and faecal coliform count whereas 1 and 1.5% had a marked bactericidal effect.
As for lactic acid, only 1 and 1.5% concentrations resulted in reduction of aerobic plate and Enterobacteriaceae count as compared with the untreated quail carcases.
On the other hand, potassium sorbate 5% was the most effective in decontaminating quail carcases regarding aerobic plate count, Enterobacteriaceae, coliforms and faecal coliforms.
In conclusion low concentrations of acetic acid, lactic acid and potassium sorbate were unreliable in their effect on the bacterial load of the examined quail carcases whereas the highest concentrations used were the most effective decontaminants.