Cooking butter samples treated with pot. sorbate (0, 0.1 and 0.3%) were analyzed weekly for microbiological quality after storage at 22, 5 and - 180C,
Less growth of microorganisms was observed in butter as the sorbate was increased from 0.1 to 0.3%, irrespective of storage temp.
Addition of 0.3% sorbate reduced aerobic plate and psychrotrophic counts, while coliforms declined to undetectable levels in all samples. No viable cells of yeast and mold were recovered after 6, 6 and 4 weeks storage at 22, 5 and -18°C, respectively. The 0.1% concentration did not prev ent growth of some microorganisms even at refrigeration temperatures.