Effect of hydrogen peroxide (H2O2) on shelf life and bacterial population of raw milk

Abstract

The present study was conducted to assess the feasibility of hydrogen peroxide (H₂O₂) for milk preservation and also to investigate the effects of H₂O₂ on growth of bacteria population in milk. Milk samples were collected from Bangladesh Agricultural University dairy farm and preserved with 0.12% H₂O₂ of 10% concentration on the basis of volume of milk and milk without H₂O₂ addition treated as control sample. Parameters used to monitor the shelf life of milk were organoleptic and chemical tests. All milk samples were kept in glass container at room temperature (28-31°C) in the laboratory. Organoleptic parameters (color, flavor, texture, taste) and chemical tests (acidity %, COB test and pH) were done every one hour interval until spoilage. Standard Plate Count (SPC) of the samples was done two times, initially and after spoilage of milk. Acidity% increased gradually in all sample but this increase was rapid in control sample than H₂O₂ treated sample. From COB test it was found that raw milk sample gave positive result at 10th hour but 0.12% H₂O₂ treated sample (after 20 min of milking ) and 0.12% H₂O₂ treated sample (after 3 hrs. of milking ) gave positive result 14 and 15th hour respectively. From the result it was observed that shelf life of milk with H₂O₂ increased. From the SPC result it was found that the bacterial growth rate is very high in control milk sample compare to H₂O₂ treated milk sample. Significant difference (p<0.01 was found in case of bacterial growth rate of the milk samples. The results of this experiment indicated that H₂O₂ be used as an effective preservative for prolonging milk preservation. So H₂O₂ can be used as an effective milk preservative for prolonging milk storage in environmental condition.

Asian Australas. J. Biosci. Biotechnol. 2021, 6 (1), 19-25