[Manufacturing Processed Cheese, supplemented with Probiotic Bacteria by Using Local Cheese (White, Karesh, Kashkaval) as raw materials.]
2011
Al-khalaileh,N
During this study many pathogenic bacteria were detect in local cheese (white cheese, karesh, kashkaval) as well as assessment of total bacterial count and analysis of chemical composition. The results of microbial analysis showed that the arithmetic mean of the total bacterial count was 3.9´107cells / g for white cheese and 1´104 cells / g for kashkaval cheese and 2.7´107 cells / g for karesh cheese. Also the results showed that 80% of white cheese samples and 28% of karesh cheese samples, and 12% of kashkaval cheese samples contained Coliform bacteria while 56% of white cheese samples and 20% of karesh cheese samples and 12% of kashkaval cheese samples contained Escherichia coli bacteria. These results also indicate that 32% of white cheese samples and 12% of karesh cheese samples and 12%of kashkaval cheese contained Staphylococcus aureus bacteria. As well as the percentage of white cheese samples containing salmonella bacteria was 4% and all samples of karesh cheese and kashkaval cheese were salmonella free. The results of chemical analysis showed that 100% of white cheese samples and 85% of kashkaval cheese samples were contrary to the standard specification with regard to their proportion of dry matter. In more details the proportion of fat in dry matter was 64% for white cheese and 42.4% for kashkaval cheese. As a result of many experimental trails and sensory evaluation the best mixture from local cheese (white cheese, kashkaval, karesh) that could be used for the production of processed cheese spread and with good sensory and chemical properties were 37.0 %, 9.0 % and 9.0 % consequently. The percentage of total dry material in produced processed cheese was 38.6%, fat percentage was 53% and total count bacteria after manufacturing and after storage for 8 weeks in temperature between 5-7c° was 5×101 cell/g .While samples which stored in temperature between 20-25° showed an increasing in total count bacteria from 5×101cell/g directly after manufacturing to 1.2×102 after 4 weeks and 2.0×102 cell/g after 8 weeks of storage without any changes in sensory characteristics. In concern to sensory evaluation the assessment of their results were processed cheese had got acceptance from consumers & panelist, And this result shows the possibility of production of processed cheese spread by using local cheeses as raw materials. We have made several mixtures from processed cheese spread supported with different probiotic strains. The first mixture, supplemented with Lactobacillus acidophilus LA-5, Lactobacillus casei 431, and Bifidobacterium, animalis subsp lactis (Bb12). The second mixture supplemented with Lactobacillus acidophilus LA-5, Lactobacillus casei 431. The third mixture supplemented with Lactobacillus acidophilus LA-5 and Bifidobacterium, animalis subsp lactis (Bb12). Mixture number four supplemented with Bifidobacterium, animalis subsp lactis (Bb12) and Lactobacillus casei 431. The total probiotic strains count number was estimated directly after the process manufacturing and after 2,4,6,8 weeks from storage in refrigerator,The results of microbial analysis showed that the number of probiotic strains in each mixture was more than 106 cells/g at the end of storage time. Also the results of total bacterial count directly after the manufacturing was for the first mixture 9.0 x102 cells/g, 1.4 x103 cells/g for the second mixture, 2.0x103 cells/g for the third mixture and 3.0x103 cells/g for the last mixture. While at the end of storage time there was a decrease in the total bacterial count as following: for the first mixture reached to 1.0 x102 cells/g, 2.2 x102 cells/g for the second mixture, 5.0x102 cells/g for the third mixture and 3.0 x102 cells/g for the last mixture. Also each mixture was yeast and mold, Coliform, staphylococcus and salmonella free. . The results of sensory evaluation by panelist and consumers showed no significant differences at P0.05 in sensory characteristics between processed cheese that supported by probiotic bacteria and unsupported processed cheese , Both kinds of processed cheese had got acceptance from consumers & panelist. The results of this study showed that the processed cheese spread was a suitable environment for probiotic bacteria growth and viability that used in the preparation higher account than those recommended when stored under refrigeration. As well as blends of processed cheese spread supported with strains of Probiotic stored at room temperature for eight weeks. A rising in the number of Probiotic observed at the beginning of storage and then got reduced to these numbers by the end of a period of storage, and accompanied the rise in the number of Probiotic a drop in the value of pH and after two weeks storage the pH reached between 5.15-5.27. And then got to the cheese curd and the separation of water and continued to decrease in the PH to reach at the end of storage to 4.08 to 4.1. This finding suggests that the storage of this type of cheese at room temperature is not appropriate.
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