CHAPTER ONE INTRODUCTION1.1 BACKGROUND OF THE STUDYKunun-zaki is a traditionally fermented non-alcoholic beverage that originates from the Northern part of Nigeria which can be produced either from millet, sorghum or maize. Kunun-zaki is a Hausa word meaning “sweet beverage,” It is now widely consumed in several parts of Nigeria owning to its refreshing qualities (Osuntogun and Aboaba, 2004). The beauty of the acceptability of kunun-zaki is the fact that it is acceptable by the two dominants religious groups (Christians and Muslims). This is because it is used as substitute for alcoholic drinks. This beverage has been found to be highly nutritious and medicinal (Goffa and Ayo, 2002). Kunun-zaki can be consumed at anytime of the day by both the adult and children. It can be taken as breakfast drinks or food complement.
It is also a refreshing drink that can be used to entertain visitors and serve as appetizer in social gatherings (Amusa and Ashaye, 2009). Kunun-zaki has poor keeping qualities which may be due to faulty processing and storage, since product is essentially a home based industry and at present, there is no large-scale factory production. This results to its proneness to microbial contamination by Lactobacillus fermentum and L. leichmannii which dominates its fermentation (Efiuvwevwere and Akoma, 1995). Food additives are used for various technological functions like improving the nutritional qualities, organoleptic properties and general acceptability of food. They also perform a variety of useful functions in food that are often taken for granted. For example, it helps keep food wholesome and appealing en-route to market.
Which can be some thousand of miles away from where it is produced or manufactured (US FDA, 1992)? Chemical or synthetic additives have been the major means of preserving foods for a long time. They are however limited in their ability to preserve foods without altering its quality parameters such as flavours, aroma and in many cases the chemical compositions. Complaints resulting from the use of synthetic additives ranges from mild one such as nausea, diarrhea and shortness of breath or even total shock after consuming such foods to life threatening disease such as cancer (US FDA, 1992). As a result, the safety of some of these additives has become the public concern and the requirement for pre-market approval and monitoring of these substances has continued to make them issue of significance (Roller, 2003).
There is a global concern about chemical residues in foods especially during storage. Consumers demand for food products with fewer synthetic additives and at the same time increased safety, quality and shelf life (Roller, 2003). Unlike in the past, consumers are more concerned about what they consume and the world is going more natural than it used to be. Many edible plants that contain complex compounds have been found to be having fungicidal and bactericidal properties, which can be extracted for use. Some have been identified and tests were conducted to establish their efficacy and suitability. There are high demands for minimally processed, fresh-like food products with high sensory and nutritional qualities. There is a growing interest in non thermal processes e.g. pulse field, dense gasses, high pressure technology for food processing and preservation (Ade-Omowaye, 2002).