CHAPTER ONE
1.0 INTRODUCTION
1.1 BACKGROUND
Kunun-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).
The
quest for natural products has led to the introduction of ‘nutra ceuticals’
which is a term used for food or part of a food that allegedly provides
medicinal or health benefits including the prevention and treatment of
diseases. Stephen De Felice coined the term from ‘Nutrition’ and
‘Pharmaceuticals’ in 1989. The result is a word that refers to dietary or
nutritional ingredients that promote optional health (Kalna, 2003). Quite a
number of works has been done at maximizing the utilization of some natural
additives, since they have been discovered to function quite well. The
antimicrobial, antioxidative and preservative effect of a number of natural
additives has been explored. Fruits, vegetable, spices, nuts, seeds, leaves,
roots and bark have been exploited as natural sources of preservatives (Kalra,
2003).
Spices
are the dried, aromatic vegetable products used in food seasonings, they
are usually of tropical or semi-tropical origin and include: barks (cinnamon),
roots or rhizomes (ginger), flowers, buds (clove), fruits and seeds (pepper,
cardamom). In most cases, spices are very aromatic and may contain large
percentages of essential oil from which they derive their main flavorings
character (Mau et al, 2001). The
potent sources of natural antioxidants are spices and herbs. Spices have been
known to impact flavor but it is now recognized that they fulfill more than
this one function in food systems, certain spices prolong the shelf life of
foods by their bacteriostatic activity, spices such as red chili, cinnamon
leaf, clove, rosemary, sage, have been reported to have antioxidant properties.
According to Pokorny (1991), when natural antioxidants are compared with
synthetic ones, natural antioxidants were found to be readily acceptable by
consumers as they are considered to be safer. Because they are from natural or
biological sources, no safety tests are required by legislation for they belong
to a component of food that is generally regarded as safe (Adegoke and Sagua,
1993). Compounds having wide spectra of anti-microbial effectiveness have been
found in thymol from thyme and iregano, allicin in garlic, engenol from cloves.
Adegoke and Sagua (1993), reported, the inhibition of microbial growth in
tomato ketchup using spices like Eeru (Xylopia
aethiopica), Ariwo (Monodora
myristica) and Atare (Aframomum
meleguata). The mixed extract from Chinese chive, and cinnamon were
reported to exhibit better inhibition on growth of Escherichia coli than potassium sorbate at 2% mg/ml. Mau et al, (2001), reported the inhibitory effect
of selected Turkish spices and oregano component on some food borne fungi.
Ginger and Aframomum danielli were also found to inhibit some food
spoilage yeast (Candida tropicalis,
Torulopsis candida and Hansenula anomala).(Adegoke and skura,1994).
1.2 Justification
Spices have been used from
pre-historic times not only as flavorant but also for medicinal purposes.
According to the International Standard Organization (ISO), there are over
Seventy (70) spices and herbs officially recognized, but more than 350 to 400
Spices are used in different Countries by people with different religion and
Climate. They are mostly of no food value; they are only added to food as
stimulant for the appetite and to aid digestion. The selection of a particular
spice for food stabilization should be based on the type of quality desired in
the food. The quantity of spice incorporated into the food must be
minimized because excess concentration
might be ineffective and not serve the exact purpose for which it is applied.
Aframomum danielli had been used to preserve
Kunun-Zaki and is at its best at 2% concentration, (Adegoke and skura, 1994).
However, the synergistic tendency of additives as found in synthetic chemical
additives can also be explored in natural additive too hence, there is need to
investigate the other spices synergetic effects on the quality of Kunun-Zaki.
The result will provide appropriate data for food processors as well as
investors in the beverage industry.
1.3 Aim and
Objectives
The
aim of this work is to study the effects of selected spices (Alligator pepper (Aframomum Danielli), Cloves (Syzygium aromaticum), and Ginger (Zingiber officinale) on the quality
attributes of kunun-zaki, a non-alcoholic beverage with the following
objectives
1.
to carry out the chemical, nutritional and
microbiological analysis on the produced kunun-zaki samples
2.
to perform sensory evaluation on the produced
kunun-zaki samples.
3.
to establish the best concentration of the spices that
can give the best quality.