Extension Shelf Life of Domiati Cheese Made by Using Some of Nat-ural Preservatives

Abstract

There is growing interest in natural ingredients that can be used as preservatives in the food industry. Significant attention is dedicated to propolis and essential oils as they often exhibit antioxidant and antimicrobial properties. Domiati cheese fortified with propolis, ginger and thyme were evaluated. The cheeses were analyzed fresh and during ripening for their chemical composition, microbiological and organoleptic properties. The addition of 5% & 10% propolis, 0.5% ginger and 0.5% thyme caused decreased in pH value but less than the control. Thyme and ginger fortified cheese caused increase in the WSN, NPN and (T.V.F.A) contents in all cheeses. The addition of 5%, 10% propolis, 0.5% ginger and 0.5% thyme respectively, had the highest effect on total bacterial count. Which indicate its antimicrobial effect on cheese microflora. Moulds, yeasts and Escherichia coli (E. coli), were not detected in treated cheese through ripening. All cheese samples made with propolis, ginger and thyme had acceptable appearance and body & texture during ripening. Propolis and essential oils can be used to improve the quality of Domiati cheese and can be used as natural preservatives to increase its shelf life up to 60 days of ripening at room temperature or at 4 C±2.