الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
Poultry meat is highly nutritious , relatively of low cost, but extremely perishable food Freezing and freeze storage is the mean by which fresh chicken meat can be maintained . Many consumers buy fresh chicken meat and freeze them at home in the household freezer (at -10°C) for la ter use Most impor tan t is the thawing prac tices emp loyed in the house, whether they invo 1 ved ; thawing in refrigerator at (5°C) or at room temperature or soaking the bird in water. Thawing of birds may occur for one time, or may repeated after refreezing Therfore, the effec t of home freezing and thawing prac tices on the nutritional and microbiological conditions of poultry meat, is the objective of this study. Fifty one broilers, chilled, packed in unevacuated pdlyethylene ~gs, and weighing 950 - 1000 gm each, were purchased from a production of one local commercial plant. 2 chickens were subjec ted to the ana 1 ysis as fresh samp les, 48 chic kens were frozen stored at (-10°C) for determinant intervals of the storage time (2, 4, 6, 8, 12, 16,20 and 24 weeks), where 6 chic kens from wh ic h were ta ken ~as samples ) for thawing by each of the three prev ious 1 y men tioned me thods , (3 chickens) for the .’ firs t time and (another 3 chickens) for second time after wevious thaw-refreezing, then all the samples were subjected for analysis. one chic ken was used for ta king an inc ipien t spoi led samp le started to be unacceptable) and also a spoiled le (after occurance of off-odour and slime formation), to be a comparative samples included with those samples subjected the isoe lee tr ic-focusing separa tion of sarcop lasmic protein e resu 1 ts of the presen t study revea led the fo llowing !) Fresh chicken meat smples have the maximum score (9) for the organo leptic charac ter is tics; co lour , odour and texture. The mean values of the examined parameters of fresh samples were; pH 6.11, moisture 74.04 , protein, fat and ash (on dry basis) were 78.77, 17.74 and 3.24 respectively, free amino acids 3.766 mg/gm, proline 0.425 mg/gm, total volatile nitrogen 17.5 mg/100gm , free fatty acids 0.316 , thiobarbituric acid 0.045 mg/kgm , and microbiological examina tions; tota I co lony coun t and tota 1 co 1 i form coun t were log 5.59 and log 2.78 respectively. 12) Frozen stored chicken meat samples showed that there is a gradual decrease in colour, odour and texture scores as the frozen time increase. However, the pane 1 scores were accepted at all intervals of the storage time until the 20th week, where the odour star tEfd to be unaccep tab le. A t the 24th week the colour started to deteriorate, while the ~xture score remained acceptable. On the u theor- ~Iand , me thud and frequency uf thawing had a little but significant effect on colour and odour but had a non significant effect on the texture. (3) Overa 11 mean va lues of the pH of fro zen stored samp les was slightly decreased (from 6.16 to 6.00) at the 8th week, then slightly increased up to the 20th and 24th week of the frozen storage time. (6.2 and 6.19) Regard less the storage time, method and frequency of thawing had non significant effect on the frozen chicken meat. I (4) Proximate composition of frozen stored chicken meat samples showed that as the storage time increased moisture, protein and ash decreased , while fat content increased for either first or second thawing, moreover the obtained mean values of the second thawing were less than those of the first thawing for moisture,protein and ash, whereas the value was more than first thawing for the fat content. Furthermore, moisture and ash content were not affected by method and frequency of thawing , but the fat was affected by only frequency of thawing (increased), while protein was 0 . affected by both frequency of thawing (decreased) and method of thawing , where the highest mean value was for the samples tnawed in water, while the lowest mean value was for the samp les thawed a t room tempera ture .