الفهرس 
MATERIALS AND METHODSOnly 14 pages are availabe for public view
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Abstract
Poultry is composed of naturally occurring water, muscle, connective tissue, bone and fat. The present work aimed to examine the marketed chicken meat products sold in Alexandria, for its content of aflatoxin and safety for human consumption through assessment for bacteriological quality with special reference to food poisoning microorganisms. In addition, the chemical composition will be analyzed to assure quality in the aspects of consumer acceptability.
Aflatoxins are still recognized as the most important mycotoxins. They are synthesized by only a few Aspergillus species of which A. flavus and A. parasiticus are the most problematic. The expression of aflatoxin-related diseases is influenced by factors such as species, age, nutrition, sex, and the possibility of concurrent exposure to other toxins. The main target organ in mammals is the liver, so aflatoxicosis is primarily a hepatic disease. Conditions increasing the likelihood of aflatoxicosis in humans include limited availability of food, environmental conditions that favour mould growth on foodstuffs, and lack of regulatory systems for aflatoxin monitoring and control.
Occurrence of aflatoxin in poultry and animal feedstuffs is quite common in many countries, and causes great economic losses (Charmley et al., 1995).(81). Accordingly protection of food and feed from the toxin is an urgent requirement. A variety of physical, chemical and biological approaches have been employed to counteract aflatoxin-related problems (Samarajeewa et al., 1990, Beaver, 1991, Piva et al., 1995, Bata and Lasztity, 1999 and Haskard et al., 2001)(203,204,205,206,207), however, most of these methods are impractical or potentially unsafe because of the formation of toxic residues or alteration of nutrient content, flavor, odor of the product.
Aspergillus flavus and Aspergillus parasiticus are weedy molds that grow on a large number of substrates, in particular under high moisture conditions. Aflatoxins have been isolated from all major cereal crops, and from sources as diverse as peanut butter and marijuana. The staple commodities regularly contaminated with Aflatoxins include cassava, chillies, corn, cotton seed, millet, peanuts, rice, sorghum, sunflower seeds, tree nuts, wheat, and a variety of spices intended for human or animal consumption. When processed, aflatoxins get into the general food supply where they have been found in both pet and human foods, as well as in feed stocks for agricultural animals. Aflatoxin transformation products are sometimes found in eggs, milk products and meat when animals are fed contaminated grains.
At least 16 different types of aflatoxin are produced in nature. Aflatoxin B1 is considered the most toxic and is produced by both Aspergillus flavus and Aspergillus parasiticus. Aflatoxin G1 and G2 are produced exclusively by A. parasiticus. While the presence of Aspergillus in food products does not always indicate harmful levels of aflatoxin are also present, it does imply a significant risk in consumption.
Aflatoxins M1, M2 were originally discovered in the milk of cows that fed on moldy grain. These compounds are products of a conversion process in the animal’s liver. However, aflatoxin M1 is present in the fermentation broth of Aspergillus parasiticus..
High-level aflatoxin exposure produces an acute hepatic necrosis, resulting later in cirrhosis, and/or carcinoma of the liver. Acute hepatic failure is made manifest by hemorrhage, edema, alteration in digestion, changes to the absorption and/or metabolism of nutrients, and mental changes and/or coma.
No animal species is immune to the acute toxic effects of aflatoxins including humans; however, humans have an extraordinarily high tolerance for aflatoxin exposure and rarely succumb to acute aflatoxicosis.
Chronic, subclinical exposure does not lead to symptoms as dramatic as acute aflatoxicosis. Children, however, are particularly affected by aflatoxin exposure, which leads to stunted growth and delayed development. chronic exposure also leads to a high risk of developing liver cancer,
The present work aimed: to assess
1-Chemical composition of raw and processed poultry meat.
2-Microbiological examination including Total aerobic bacterial count, Salmonella and E.coli.
3-Aflatoxin examination of raw and processed samples.
This assessment attempts to bring together available scientific and technical information on food safety hazards associated with poultry meat and poultry meat products in Alexandrea and describes stages of production and processing that have impacts on these hazards.By collecting 75 of poultry samples from Alexandria markets . 25 of them were raw samples randomly from the 6 districts areas in Alexandria (West, East, Gomrouk, Montazah, America and Middle) and 50 were processed samples from products of three local factories randomly also the samples were Nuggets, Hot crispy chicken pan, Chicken Fillet.
Determination of chemical composition of examined raw and processed samples of the three factories.
Determination of protein content
Determination of crude fat content
Determination of ash content
Determination of moisture content & total solids.
By analysis of the chemical components of the raw samples the results were within the normal levels of proteins ,fat,moisture, charbohydraye and ash .
But the chemical components of the processed samples the results were low in proteins and high in fat and so the carbohydrate were higher in processed than in raw samples.
Evaluation of poultry samples by microbiological examination of raw samples and processed samples of (A, B, C), the three common factory brands
Microbiological examination:
Bacteriological examination
Determination of Total Aerobic bacterial count:
The total bacterial count of processed poultry samples The minimum number was 6 ×(10)4 (CFU/ g ) and the maximum number was 112×(10)4(CFU/ g) with a mean of 60×(10)4 while in raw poultry samples total bacterial count ranged from the minimum number was 23×(10)4(CFU/g) while the maximum number was 81×(10)4(CFU/g). with a mean of 51×(10)4(CFU/g).
Determination of salmonella and E.coli:
The incidence of salmonella in the examined raw samples were 56.0%,while salmonella was isolated from examined processed samples, at 68.0% and the free samples from salmonella microorganism were 32%. from this result it is found that the incidence of salmonella species in processed samples were higher than in raw samples .
The incidence of E. coli in raw samples was 36%, while the incidence of E.coli species in processed samples was 64.0% there for the incidence in processed samples was higher than the incidence of E.coli in raw samples . The microbiological examination also show heavy infestation with salmonella and E,coli in both raw and processed samples
Identification of Salmonella and E.coli
The organisms that have generated the most interest in relation to the public health and safety of poultry meat, both domestically and internationally are Salmonella species and E.coli species. The microbiological examination for both the raw and the processed poultry samples reveals that all processed samples exist the presence of large numbers of total aerobic bacterial count and the raw samples show less numbers .
Mycological Examination
Total mold and yeast isolation and identification
The mycological examination show that raw samples were free of fungi but there was various kinds of fungi in processed samples, it was observed that the highest percentage was Aspergillus niger was 68% , followed by Candida albicans was 44%, Penicillin species was 44% then Rhizopus in samples was 28% , Dematiaceous fungi (Alternaria) was 24% , while the lowest percentage was Aspergillus flavus, and Fusaruim species in samples was 4%.
Extraction and determination of Aflatoxins
Raw samples were free of aflatoxins . and in processed samples have aflatoxins B1, while the aflatoxins B2, G1, G2, were not detected by analysis with the HPLC .
Conclusion :
from our results, we can conclude that :
1-The addition of spices and processing bread crumbs led to an increase in Aflatoxin B1 which means attention should be focused on the additives and the overall increase in Aflatoxin content of processed chicken.
2-Protein content was higher in raw samples than that of processed samples which means that the processed ones were having some additives with low protein value or may be exposed to bad storage conditions led to protein degeneration .
3-Processed poultry samples were higher in fat which is dangerous for heart, obesity hyper cholesterolaemia, and may cause risk of obesity to children .
4- Both raw and processed samples were high in salmonella species , E.coli
5-The raw samples were free from moulds, and yeast contamination, while the processed samples contained large verities of fungi species.
6-There was significant Aflatoxin contamination of processed poultry samples , while the raw samples were free of the Aflatoxins .
7- This work established a pioneering concept that Aflatoxin B1 may be considered as an etiological factor for a novel food borne zoonosis identified as Aflatoxicosis B1.
Recommendations :
It is recommendded that :
1- For poultry producers :
Its recommended that all poultry producers follow the hygienic measures .
For the live birds they must follow the system of medication and vaccination to produce birds free of microorganisms as possible .
2- For poultry manufacturers :
For the manufacturers they must follow the sanitation in production and hygienic measures in handling , transportation ,storage and marketing . selection of components and their compatibility.
3- For poultry consumers :
For the consuming persons they must make proper handling in their preparation method ,they must check the expiry date and ingredients on the label, using famous good brands with high quality, checking the packages (containers) of the products before use.
Medical researches indicates that a regular diet including vegetables such as carrots, parsnips, celery and parsley, reduces the carcinogenic effects of Aflatoxin.
4- For authority or responsible peoples:
Strict supervision should put in concentration for the health authority in processed poultry meat that used by consumers, to adjust the hygienic conditions of processing and the total ingredients specifically protein ,fat percentage and the additives to the final product . Increase control on market processed and raw poultry distribution . Much more stringent inspection of processed poultry markets are needed to detect and remove adulterated samples.
5- A large number of food samples will be needed to completely assess the situation.
6- It is important to evaluate which one of the additives carry the Aflatoxins
because the raw samples were free of Aflatoxins .