الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
In order to provide an effec ti ve storoge lif’e of’ many weeks, some vegetables need to be frozen and then stored substantially below the freezing point of water. These low temperatures are needed to preserve the flavor, odor, color and texture of the food by retarding chemical changes, by retarding the action of food enzymes, and by eliminating the growth of micro-organisms capable of growth near or below 32°f (0° C). This study was conducting on the existing hygienic , condi tians of’ frozen vegetables of Edfina. Company with the following objectives: 1- To assesS the organoleptio properties. 2- TO evaluate the hygienio conditions during processing. 3- To determine the effect of different processes as well as freezing and storoge on the bacterial load of raw , veget ab lea.’ 4- .:ro assess the presence of fecal streptococci, E!. c.oli and coliforms as an indication of contamination in relation to the hygienic quality of the product. A total of 210 sa.mples of raw, washed, blanched, packaged, fro~en and stored of the following vegetables: Okra, Jew’s Malloy and Beans. They were collected at random from Edfina company 2.nd were examined: 1- Physically to notice any change in color and odor. 2- Microbiologically to determine total bacterial count, coliforms, PL. c,91i, fecal streptococci and psychxophils, The result of this study revealed the following: 1- Physical properties: All frozen and stored samples shov/ed no change in color and odor. 2 - Microbiological examination: : The average bacterial counts were 2.47 x 1012, 4.75 x 1012 and 1.75 x 1010 per gram and the average . 8 8 ’7 ps.yc~J’ophils cOilllts were 2.5 x 10 , 8.25 x 10 and 7.8x 101 J per gram of raw Okra. Jewt G Mnlloy and:B8Jons , reapGcti v61y. Washing the vegetro.bles with tap vmter gave a small reduction in counts. The blanching process caused apprecisble reduction in total bacterial counts to 3.93 x 104, 2.8x 105 and 1.2 x 104 p~r gl~m, and in psychrophils counts to 4.2 x 103, 7.25x 103 and 1.9 x 103 per gram for 0kI.”a,Tew’sIv!al1oy [:..1ld.. Beans, respectively. Following the process the bacterial load in”reased . 6 7 c:, The total counts v/ere 6.9 :z: 10 , 9.8 x 10 and 4.1 x 10’ per gram and psychrophils counts were 6.9 x 105, 5.2x 105 and 9.8 x 104 per gram of paclro.ged Okra, Jaw’s r~’)lloy and Beans, respectively, The freezing process causes 38.3 to 88.1reduction in total bacterial counts. For psychrophils counts 5T:;~, reduction occurred in Okra samples and 7.2 reduction for Beans samples, while in case of Jew.s Malloy aalUples 9.5 increase occurred. 0 Storing the vegetables for 3 manths at -18 C gave 53.2 to 86.8 reduction in total bacterial counts and 40.4 to 80.3 rec~uction in psychrophils counts. Storing the vegetab le s for another two months gave 6.7 to 24.3 reduction in total cow~ts, while the psychrophils counts increased by 1.1 to 26.4. In case of coliforms and fecal streptococci, relatively large numbers were recovered from vegetubles at all stages of processing. These counts are usually parallel to each other, sample having a high total count often yield a relatively large nwnber of coliform and fecal streptococci. The redu.c tion in counts due to freezill8 and s”Gorage was more pronounced in case of colifol1ms than in cese of fecal streptococci. E..!,. coli was found in all raw and washed veGetables. For Okra and Beans, the organism disappeared after blanchinG and was not detected in the frozen product. While in case of J€W’S Malloy the organism was isolated from the samples at most stages of processing. During storage at -180e for 5 months the organism almost disappeared. These results shO’vv the importance of the initial total count of vegetables in governing the subsequent stages of proces;:; ing. Moreover it has been observed that any delaj- in processing is very deteriorus to the quality of the product. The M.P.N. of fecal streptococci was generally highand were present in all saillples during all processes, thus can between as a better indicator for the hygienic quality of the product at any stage. The use of E.- coli as a test organism was not satisfactor:l because this organism died during the storage of the frozen food.