Effect of nisin on shelf life of low salt Tallaga cheese

Ibrahim, Ekbal M. A.; Sobeih, Azza M. K.

doi:10.21608/jvmr.2005.77937

Effect of nisin on shelf life of low salt Tallaga cheese

Document Type : Original Article

Authors

¹ Department of Food Control, Faculty of Veterinary Medicine, Moshtohor, Benha University, Moshtohor,Egypt

² Department of Food Hygiene, Faculty of Veterinary Medicine, Kafr- El-Sheikh, Tanta University, Kafr- El-Sheikh, Egypt

10.21608/jvmr.2005.77937

Abstract

Tallaga cheese was made from reconstituted partially skim milk powder (2% fat) with two salt concentrations (1% and 3%) and then (50, 100, 200 IU/ml) nisin were added. Control groups of both salted Tallaga cheeses were manufactured without addition of nisin. Furthermore, the two types of Tallaga cheese samples were kept in their whey at refrigerator temperature (2-4oC) till signs of spoilage were observed. Periodically, the control and preserved samples were examined chemically (pH and titratable acidity) and bacteriologially (aerobic plate, psychrotrophic, coliform and aerobic sporeformer counts) to determine the influence of nisin on prolongation of their shelf life. Nisin extended the shelf- life of low- salt cheese (1% salt) up to 8 days at concentration 100 IU/ml and up to 10 days for 200 IU/mL, while; nisin-free cheese samples were spoiled after the 4th day of refrigeration storage. On the other hand, the shelf life of 3% salt cheese was extended up to 20 days of cold storage by addition of nisin at conc. 100 and 200 IU/ml. In contrast, the cheese samples of control group were deteriorated after the 8th day of refrigerated storage. There were significant differences (p < 0.05) between the chemical and bacteriological profiles of low salt soft cheese as a result of storage time. Actually, the nisin had a significant destructive action on contaminating coliforms and aerobic spore forming bacteria of Tallaga cheese and lead to increase its validity period.

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