Penicilliosis in cheese

Abstract

The AA. revise the outstanding factors that condition growth of fungi in products, after commenting upon mycotic contamination of food, especially milk derivatives. Upon investigating the responsibility of alterations presented by cheese from the "Fábrica Escola de Laticínios Cândido Tostes” in Juiz de Fora, they were able to isolate a fungos of the Penicillium genus, its species having not been determined. The AA. were able to reproduce alterations experimentally with the sample isolated. The AA. proceed to discuss the various ways that practice employs in order to avoid food’s contamination by fungi. In this case no results were obtained through hygienization of the establishement and its departaments by means at hand. The AA. then made up their minds to study, experimentally, the prophylaxy of the alteration acting upon the products. No use was made of propionic acid or its sodium and calcium salts, because, as been observed by various experimenters, these compounds have to be employed in concentrations such as to determine changes upon the organoleptic characters of cheese. Besides, the genus Penicillium has a markeddly higher resistance to the fungistatic properties of propionates. The work of Turner and others reminded the AA. the use of "Merthiolate” (ethyl-mercuri-thiosalicilate) in preventing penicilliosis in cheese. Preliminary experiments "in vitro” have shown this compound to have a marked hindering action (when diluted 1:50.000) upon growth of Penicillium isolated from cheese. The action of "Merthiolate” was observed upon 16 samples of various fungi, among which the Penicillium isolated from cheese; the AA. were able to ascertain that, as a rule, molds suffer the fungistatic effects of this compound more intensely than yeasts do. Upon essaying in laboratory, with experimental purposes, the action of "Merthiolate” upon cheese, the AA. prove that immersion in a solution of this compound is by far the most efficient prophylactic method bearing reference to penicilliosis. Experiments made afterwards show that have to be treated by "Merthiolate” in concentrations of 1:25.000 before receiving paraffin; the dilution may be weakened even to 1:50.000. The inhibitory effect of this weakened solution is the stronger in direct rate to the time in which it is kept in contact with the cheese. Practical use of sodium ethyl-mercuri-thiosalicilate (Merthiolate)in prophylaxy of cheese molding in creameris will be the subject of another work.