Abstract:
Use of hygienic packaging materials is very important to avoid microbial
contaminations that lead to poor shelf life of curd. Microbial and dust
contaminations in clay pots are found to be a major problems in using them
for curd packaging and therefore proper cleaning and sterilization of clay
pots is essential. The present method of washing, potassium sobate
treatment and re-firing is not satisfactory due to poor shelf life of curd and
high cost of production. Therefore, the main objective of this experiment
was to evaluate the effectiveness of steam injection for cleaning dust and
sterilization at once of the clay pots used for curd packaging. Five
treatments; steaming inside, steaming both sides, steaming and 1%
potassium sobate application inside, steaming and potassium sobate
application on both sides and control with four replicates were used for the
experiment. A simple com type steam injection nozzle was directly
connected to a high pressure steam hose. Pots were treated according to the
treatments and total colony counts were determined in pots using Ringer
solution and cotton swabs for rubbing the surface and milk agar as the
culture media. In addition, the Coliform test was also conducted. Mould
growth on the packed curd was observed visually and pH of curd was also
measured during storage. The cost analysis was also done to evaluate the
feasibility of the new technique and compare with the present method.
According to the results, steam blast sterilization significantly reduced
(P>0.05) the microbial counts compared to the current method. Further, the
combination of steam blasting and application of 1% potassium sobate on
the inner surface was found to be the best treatment. The shelf life of curd
could be extended by four days up to 11 days while reducing the cost to a
half.
