J. Agric. Res. Kafrelsheikh University, 33, 348-359. 348 Prevention of fungal growth on Ras cheese surface using some plant extracts under different hygienic conditions Mohsen A. Zommara, Eman M. Ibrahim and Mostafa A. Rashed 1 Department of Dairy Science, Kafr El-Sheikh University, Kafr El-Sheikh 33516, Egypt. Abstract Ras cheese was subjected to surface treatment with ethanolic (EE) or water extracts (WE) of cinnamon, cumin, ambrosia and wheat or their mixture with or without 5% of sodium bicarbonate or calcium carbonate. The cheeses were stored for two months for ripening under bad or good hygienic conditions and the fungal growth rate on cheese surface was visually evaluated during storage period. The results showed that the EE and its mixture had significant antifungal effect than that of the WE. Among all plant extracts cinnamon extract was the most effective one. The mixture of EE with 5% of sodium bicarbonate appeared ability to prevent the fungal growth on cheese surface stored under uncontrolled hygienic conditions. On the other hand, the controlled hygienic conditions resulted in less fungal growth on cheese surface which inhibited by the mixture of EE or WE with sodium bicarbonate. The in vitro inhibitory effect of acetonic extract (AE) of different plants on growth of some predominant fungal strains (isolated from Ras cheese surface) was also examined. The AE of cinnamon and cumin were more effective in inhibition of fungal growth followed by galangal and sage. Furthermore, The AE of ambrosia, cinnamon, cina, and cumin completely inhibited the growth of Saccharomyces cervisiae. Finally the commercial oils of anise, cina, cinnamon, cumin, nigella and sage showed no in vitro antimycotic activities. Key words: Ras cheese, herbs, spices, fungicides Introduction Ras or so called Romi or Turkey cheese is the best-known national hard cheese in Egypt. It is widely manufactured either in simple dairy pilots or in 1 Correspondence author.