Propionic Acid, Sodium Propionate and Calcium Propionate as Inhibitors of Mold Growth. I. Observations on the Use of Pro-Pionate-Treated Parchment in Inhibiting Mold Growth on the Surface of Butter

Abstract

Summary 1.Parchment paper treated in five per cent calcium propionate solution acidified to pH 5.5 with lactic acid was fully as effective in inhibiting mold growth on unsalted butter as parchments treated in ten per cent unacidified solution. Further, butter wrapped in parchments treated in the five per cent acidified solution showed marked superiority in keeping quality, as judged by surface flavor over controls or other prints wrapped in parchments treated in unacidified solutions of higher concentration. 2.No advantage was obtained by using a solution consisting of a mixture of either propionate with sodium chloride for the treatment of wrappers. Solutions of either propionate were superior to a saturated solution of sodium chloride for the inhibition of surface mold growth. 3.Below 0° F. pre-storage of butter, wrapped in propionate-treated parchment, did not prevent subsequent protection against mold growth on storage at higher temperatures. 4.Calcium-propionate-impregnated parchments were found to be effective only when used in dry wrapping. Immersing such paper in water before wrapping resulted in leaching the propionate from the paper and consequently a loss of effectiveness. 5.Heating acidified or unacidified propionate solutions did not impair their effectiveness. 6.The species of Penicillium used was markedly more resistant to the inhibiting effect of the propionates than species of other genera studied.