الفهرس 
Meat in EgyptOnly 14 pages are availabe for public view
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Abstract
Egypt is one of the most countries which the animal’s meat and their fats are highly consumed especially pork (for non-Muslim people), beef, chicken, sheep and their blends.
The main objective of the present study is to apply a specific method for detection the adulteration with pork derivatives in some meat products commonly produced or imported and consumed in Egypt.
To fulfill this objective, four pure edible animal meats and their fats were purchased from butchers who were known to sell only one type of meat (Pork, beef, chicken and sheep) and thirty one samples of the commercial processed meat products were collected from several markets with different trade names and production dates.
•Fats were extracted from each type of meat and from their adipose tissues, and then refined.
•Refined fats from adipose tissues were mixed to form blends of two types of refined fats (24), blends of three types of refined fats (9), and Blends of four types of refined fats (3) with different weight proportion.
•The four types of meats were mixed to form 6 blends with different weight proportions.
•Protein was extracted from different types of meats and mixed to form 6 blends with different weight proportions.
•Protein was extracted from different types of raw adipose tissues and mixed to form 3 blends with different weight proportions.
•Proteins was extracted from different types of refined fats of adipose tissues and mixed to form 3 blends with different weight proportions.
•The fat and protein were extracted from processed meat samples.
•The fats extracted from pure animal meats, adipose tissues, processed meat samples and the different fats blends were analyzed by chromatographic (GC), spectrophotometeric (FT-IR) and microscopic methods.
•The proteins extracted from pure animal meats, their formulated protein blends, and the proteins extracted from collected processed meat samples were analyzed by immunoassay-based detection kits (ELISA).
The results of the present study revealed the following:
•The fatty acids composition of the fat extracted from chicken meats showed nearly the same percentage ranges of fatty acids composition of the fat extracted from pork meats.
•The fatty acids composition of the fat extracted from sheep meats showed nearly the same percentage ranges of fatty acids composition of the fat extracted from beef meats; this depends on the animal location from which the fat was extracted and the diet used.
• The fat extracted from beef meats showed the highest percent of saturated fatty acids (56.805%), followed by fat extracted from sheep meat (50.628%), then pork (37.051%). Chicken fat should the lowest (34.921%).
•The fat extracted from pork meats showed the highest percent of monounsaturated fatty acids (52.341%), followed by fat extracted from chicken meat (51.840%), then sheep (47.344%) ،Beef fat should the lowest (40.521%).
• The fat extracted from chicken meat showed the highest percent of polyunsaturated fatty acids (13.085%), followed by fat extracted from pork meat (10.609%), then beef and sheep (2.674% and 1.66%).
• The fat extracted from chicken and pork meats were characterized by high percentages of linoleic acid C18:2 (12.536% and 10.072%) compared to beef and sheep fats (2.674% and 1.212%). This fatty acid nearly equals strearic acid C18:0 (10.105%), (9.536%).
• The fat extracted from pork meat and chicken meat showed the absence of eicosadienoic (C20:2) which is used as preliminary screening for pork fat this was due to the low fat extracted besides the location from which the fat was extracted.
• All fats extracted from the examined animals meats showed the presence of minor peaks in the chromatogram represented by the following fatty acids: myristoleic C14:1, pentadecanoic C15:0, pentadecenoic C15:1, palmitoleic C16:1, heptadecanoic C17:0,and heptadecenoic C17:1, indicating that the fats were from animal source.
• The fat extracted from adipose tissues of beef and pork showed higher percentage of saturated fat (62.713% and 43.299%) than fat extracted from their corresponding meats. While, the fat extracted from adipose tissues of chicken and sheep showed lower percentage of saturated fat (28.171% and 39.166%) than fat extracted from their corresponding meats.
• All fats extracted from the examined animals adipose tissues had minor peaks represented by the following fatty acids with different relative percentages: myristoleic C14:1, pentadecanoic C15:0, pentadecenoic C15:1, palmitoleic C16:1, margaric C17:0. margaroleic C17:1 and these fatty acids indicates that the fat originated from animal source. Lauric C12:0 was found in fats extracted from adipose tissues of pork, sheep and beef (0.753% to 0.060%), while not found in chicken fat.
• The fat extracted from adipose tissues of the four animals showed the presence of ecosanoic acid C20:0 at different levels ranging from 0.090% to 0.724%. This fatty acid was absent in all fats extracted from animals meats.
• The fat extracted from the adipose tissues of the four animals showed the presence of eicosadienoic acid C20:2 in only pork and chicken fats at different levels (0.301%, 0.049%) respectively. This fatty acid was absent in all fats extracted from animals meats.
• There was certain fatty acids which was characteristic for pure animal fats (e.g linoleic acid C18:2 and eicosadienoic C20:2 (a preliminary marker for detection of pork fat), provided that no vegetable oils/fats added and no feeding with diet containing high percentage of both C18:2 and (C20:2) which influence their original percentages.
• Pork fat extracted adipose tissues were characterized by high percentage of linoleic acid C18:2 (13.580%) which nearly equals to strearic acid C18:0 (12.797%) and both were higher than in fat extracted from meat (10.072% and 9.536%). Also, the presence eicosadienoic C20:2 (0.301%) which used as preliminary screening for pork fat.
• Beef fat extracted from adipose tissues was characterized by low percentage of linoleic acid C18:2 (1.890%), it was slightly higher in fat extracted from meat (2.674%). Eicosadienoic C20:2 was absence in both of them.
• Strearic acid C18:0 was found at higher level (34.167%) in fat extracted from cow adipose tissues than that extracted from meat (24.967%).
• Chicken fat extracted from chicken meat was characterized by the highest percentage of linoleic acid C18:2 (12.536%) which was higher than strearic acid C18:0 (10.105%) and the absence of eicosadienoic C20:2.
• Chicken fat extracted from chicken adipose tissues was characterized by the highest percentage of linoleic acid C18:2 (18.198%) and the relatively low percentage of strearic C18:0 (6.074%) and the presence of eicosadienoic with low percentage C20:2 (0.049%).
• Sheep fat extracted from sheep meat was characterized by the lowest percentage of linoleic acid C18:2 (1.212%) and the absence of eicosadienoic C20:2.
• Sheep tallow extracted from sheep adipose tissues was characterized by the low percentage of linoleic acid C18:2 (1.462%) and the absence of eicosadienoic C20:2.
• The fatty acid profile of palm olien, cottonseeds, soyabean and sunflower oils showed the absence of C14:1, C15:0, C15:1, C17:0, C17:1,C20:0, C20:1 and C20:2. C12:0 was present in only palm olein and C14:0 was present in only palm olein and cottonseeds oil.
• The blending of pork fat with beef, chicken and sheep fats showed the presence of C20:2 at higher levels than that resulted from the blending of chicken fat with beef and sheep fats.
• The FT-IR spectra of pork fat and the other pure animal fats appeared to the naked eye fairly similar.
• Chicken fat had the highest wavenumbers (ύ cm-1) values for the bands e,f,t and z and the lowest values for the bands r and s , this was because chicken fat had the lowest total saturated fatty acids.
• Beef fat had the lowest wavenumbers (ύ cm-1) values for the bands e,f,t and z and the highest values for the bands r and s , this was because beef fat had the highest total saturated fatty acids.
• Beef fat had the highest wavenumbers (ύ cm-1) values for the bands c and u while sheep fat had the lowest wavenumbers (ύ cm-1) values for the bands c and u, this was because beef fat had the lowest monounsaturated fatty acids while sheep fat had the highest monounsaturated fatty acids.
• Pork fat had values of wavenumbers (ύ cm-1) for the bands e,f,t,z,r,s,c and u among that for beef, chicken and sheep fats.
• Practically there were no specific spectra or characteristic wavenumbers (ύ cm-1) for pork fat (lard) in fat blends because any addition of any kind of fat will change the values of their wavenumbers (ύ cm-1).
• All blends of fats extracted from standard animal adipose tissues containing pork fat showed characterized crystals of pork fat and the number of these crystals increased with increasing the concentration of pork fats in the blend.
• All fats extracted from the standard animal meats including pork meat do not show the characterized crystals of pork fat, this is because of the low fat extracted and the heat used in extraction the of fat from the meat by organic solvent break these crystals.
• The fats extracted from the collected meat samples don not show the characterized crystals of pork fat.
• All blends of standard animal meats containing pork meat showed positive results (green color) for the detection of pork using Enzyme-linkage immunosorbent assay technique (ELISA).
• All blends of standard raw adipose tissues containing containing pork fat with 10% or more showed positive results (green color) for the detection of pork using Enzyme-linkage immunosorbent assay technique (ELISA).
• All processed meat samples collected from the market showed negative results for pork detection using Enzyme-linkage immunosorbent assay technique (ELISA).
Recommendations
1. It is recommended to use the immunoassay method for the detection of pork in raw or processed meats products. The fat-based method could be used.
2. If the sample contains only fat, then we recommend the C20:2 method for preliminary screening followed by microscopic analysis of fat crystals unless the fat crystals were damaged during processing.
3. It is not suitable, the use of spectroscopic analysis by FTIR for detection of pork fat although it requires less sample preparation and short time where it is not accurate. This method may be possible for only known pure fats.