American Journal of Biochemistry 2014, 4(1): 1-5 DOI: 10.5923/j.ajb.20140401.01 Determination of Inhibitory and Flavour Compounds in Fermented Camels Milk (Gariss) Abdallah A. Alyan 1 , Abdel Moneim E. Sulieman 2,* , Abdelrahim A. Ali 3 , Abdlulaziz S. Bahobail 4 1 Department of Biotechnology, Faculty of Science, Taif University, Kingdom of Saudi Arabia 2 Department of Biology, faculty of Science, University of Hail, Kingdom of Saudi Arabia 3 Department of Chemistry, Faculty of Science, Taif University, Kingdom of Saudi Arabia 4 Department of Miccrobiology, Faculty of Science, Taif University, Kingdom of Saudi Arabia Abstract In the present study, some of the inhibitory compounds such as lactic acid, acetic acid and citric acid were determined in Gariss samples obtained from two sources, Kordofan (Western Sudan) and Botana (Central Sudan). The mean values of these acids contents were 0.99, 0.070 and 0.30 (mg/100g) in Kordofan Gariss, and 0.86, 0.064 and 0.308 (mg/100g) in Botana Gariss respectively. The flavour compounds such as acetaldehyde and volatile fatty acids found in Gariss were also determined, however, the mean values of the acetaldehyde contents at 0, 10 th , 20 th and 30 th day of storage were 22.60, 40.50, 39.40 and 30.70 (µmol/ml) in Kordofan Gariss, and 22.50, 40.22, 32.50, 30(µmol/ml) in Botana Gariss, respectively. However, the mean values of total volatile fatty acid contents at 0, 10 th , 20 th and 30 th day of storage were 4.0,4.0,6.0,6.0, of 0.1 ml NaOH/10ml in Kordofan Gariss 4.4,4.0,6.0,6.0 and in Butana Gariss s, respectively. Keywords Acetaldehyde, Lactic acid, Citric acid, Volatile fatty acids 1. Introduction Fermentations transform the original food by producing acids, alcohols and volatile Compounds that add flavor and aroma. Some of these chemicals are antimicrobials. They inhibit the growth of undesirable pathogens and Spoilage microbes. Thus fermentation preserves food. Generally, fermentation is a self-limiting process. The accumulating acids and alcohols eventually Kill even The fermenting microorganisms themselves. Microorganisms of lactic acid starter cultures used for the conversion and preservation of milk by-products are unique bio-converters of energy. When they are used appropriately, these cultures elaborate specific metabolites during fermentation these metabolites, in conjunction with partial hydrolysis of milk constituents (proteins, fat and lactose) contribute to better digestibility of the fermented food and their nutritional and therapeutic qualities also are enhanced. The camel population in Sudan was estimated at 3.724 million head according to the Ministry of Animal Resource and Fisheries[1]. In Sudan, camel’s milk and the fermented camel’s milk (Gariss) are widely consumed by the rural people and pastoralist communities inhabiting the arid and semi-arid regions of the country. * Corresponding author: abuelhadi@hotmail.com (Abdel Moneim E. Sulieman) Published online at http://journal.sapub.org/ajb Copyright © 2014 Scientific & Academic Publishing. All Rights Reserved Flavour is a crucial characteristic of foods as the sensory characteristics play an important role in product acceptance by consumers. In fermented dairy products, flavor perception is strongly based on the volatile components[2]. The most prominent ones are mainly lactic acid which imparts an acidic and refreshing taste, and a mixture of various carbonyl compounds like acetaldehyde, ethanol, acetone, diacetyl and 2-butanone. However, among them, acetaldehyde is considered as the major flavor compound for the typical yogurt aroma reported by several researchers [3][4]. Gariss which is prepared from camel’s milk, is prepared made by semi-continuous or fed-batch fermentation process in large skin bags or siin, which contains a large quantity of previously soured product[5]. The objective of the present study was to determine the contents of the inhibitory compounds as well as flavour components of fermented camels milk product (Gariss). 2. Materials and Methods Traditional Gariss samples were obtained different locations in Kordofan “Western Sudan” and Butana “Eastern Sudan”. Each sample was transferred to 250 ml autoclavable plastic container. The samples were Kept at 4°C and transported to the Food Technology Research institute-Egypt. Analyses were carried out at 0, 10 th , 20 th , and 30 th day of storage at 4°C.