الفهرس 
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Abstract
Six groups of Alexandria semidry sausages were produced using different types of probiotics, (B. lactis, L. casei, L. acidophilus, L. lactis, mixture of B. lactis and L. acidophilus as well as a mixture of L. casei and L. acidophilus). The product was examined during both fermentation and storage period. Sensory examination revealed that different probiotics did not significantly affect appearance and texture attributes, while refrigerated storage resulted in a significant increase in color non-uniformity, decrease in cohesiveness, chewiness, juiciness, odor and flavor. Chemical examination showed that moisture content reduced with a concomitant increase in protein, fat and ash content during both fermentation and storage periods. Mixture of L. casei and L. acidophilus and L. lactis resulted in the highest moisture loss at the end of fermentation period. There was a significant decrease in nitrite content and significant increase in salt content regardless type of probiotics used. Using L. casei and L. lactis significantly increased total soluble proteins in the beginning of fermentation period, while refrigerated storage resulted in significant decrease in total soluble and sarcoplasmic proteins content regardless the type of starter culture. Different types of starter cultures resulted in a gradual increase in acidity and a decrease in pH during fermentation period followed by decrease in acidity and increase in pH during storage period. L. casei and a mixture of B. lactis and L. casei produced the highest acidity at the beginning of fermentation period. TVBN and TBARS significantly increased during both fermentation and storage period. L. casei resulted in a significant increase in TVBN while incorporation of B. lactis resulted in the highest TBARS at the end of storage period. Refrigerated storage resulted in a significant increase in firmness of the product in the late stage of storage. A mixture of L. casei and L. acidophilus had the highest shear force value. Sausages treated with a mixture of L. casei and L. acidophilus were significantly lighter than other treatments. Refrigerated storage resulted in negative impact on lightness with increased redness and yellowness. Using mixture L. casei and L. acidophilus decreased the level of 2-phenylethylamine, putrescine, cadaverine, histamine and tyramine while all types of probiotics resulted in slight increase in tryptamine and spermidine level. Microbiological examinations revealed significant increase in lactic acid bacteria and decrease in total yeast and mold count throughout fermentation phase followed by a decrease in lactic acid bacteria below the detectable limit and increase in total yeast and mold count through the storage period. Moreover, different types of probiotics resulted in a significant reduction in lipolytic and proteolytic bacteria as well as Staphylococcus aureus and Enterbacteracae below the delectable limit.