Characteristics of Domiatti Cheese Made from Milk Containing Formalin

Abstract

Although formalin is hazardous to human health, several cheese makers in Egypt illegally add a small amount of the chemical to cheese milk to improve the body, texture and yield of cheese. Cheese was made from milk containing from 0.0 to 0.1% formalin to study its effect on the chemical and bacteriological characteristics during ripening. The pH value and moisture content of cheese made from milk containing formalin were slightly increased, whereas the acidity and amino nitrogen content were slightly decreased when compared to control cheese. The effects were proportional to the amount of formalin added. Formalin could not be detected easily after 2 to 4 days in cheese made from milk containing 0.002 or 0.008% of the chemical, whereas when cheese was made from milk with 0.02 to 0.1% formalin, the chemical was detectable for up to 8 weeks. Formalin at a concentration of 0.001 to 0.002%, when in milk used to manufacture Domiatti cheese, failed to inhibit growth of microorganisms and to prevent subsequent ripening of cheese. However, formalin at concentrations of 0.02 to 0.1% caused a marked reduction in the total count, which was proportional to the concentration of formalin; no selective action on the different groups of bacteria in cheese was observed. Formalin caused an increase in cheese yield proportional to the amount of formalin added and also improved texture of cheese.