Abstract:
Nisin is a polycyclic antibacterial cheese. It is a bacteriocin effective
eptide which used as a preservative in against many Gram-positive organisms
including lactic acid bacteria. Hence, the present work was undertaken to assess the effect of Nisin on post-processing acidification and the lactic acid
bacteria population of curd. Curd was prepared using freeze dried curd
starter cultures and was divided in to three groups. 0.015% (w/v) of Nisin and 1000 mg/Kg of Potassium Sorbate (E 202) were added to two parts
separately while the remaining part was kept without adding any
preservatives (control). Curd samples were analyzed for lactic acid bacteria population, titratable acidity and pH for 10 days period while storing at 4oC. Incorporation of Nisin in to curd reduced (P<0.05) the lactic acid bacteria
population than the control (curd without any preservative) by 1.27 log
CFU/mL at day 01 of refrigerated storage. Nisin incorporated curd samples showed slightly higher (P>0.05) pH and lower Titratable acidity than the curd without any preservatives (control) at day 1 of refrigerated storage.
Therefore, this study revealed that Nisin can reduce the post-processing
acidification of curd than Potassium Sorbate upon refrigerated storage up to 10 days.
