1.1 Background to the Study
Locust bean, Parkia biglobosa is a tree
of the genus Parkia in the family Fabaceae. In West Africa, its fruits
are fermented to a condiment called 'Soumbala' or dawa dawa (Bonkounhou,
1987). The striking red spherical inflorescences which appear in the
dry season, are often used by children for games (Burkill, 1996). The
yellowish powder inside the seed pods is sweet and can be eaten without
preparation and can also be made into drinks. The pods are boiled to
male a black liquid used for sealing floors (Hall et al., 1996). It is a
perennial deciduous tree with a height ranging from 7 to 20m, although
it can reach 30m under exceptional conditions (Hopkins et al., 1984).
Its seeds are fermented to make dawa dawa, a black strong smelling tasty
food high in protein (Steinkraus, 1996).
In the tropics, especially in Nigeria,
locust bean is processed locally into constable delish and is a part of
traditional dishes in most parts of the country. It is sold in the
Nigerian co sumables markets in two forms, the mashed and the unmashed
locust bean. During the Nigerian processing of locust bean, salt is
usually added to prevent microbial contamination and growth. However,
inspire of procedures engaged, locust bean could still harbour loads of
microorganisms especially while handling. Moisture, ash, fiber, protein
and fat in Parkia biglobosa infer the nutritional value of locust bean.
Previous reports reveal that dawadawa is rich in protein, lipids and
Vitamin B2 (Hopkins,1983) and that fermented beans are rich in lysine
(Hopkins, 1983; Steinkraus,1996). According yo Hong et al., (1996).
Parkia biglobosa seeds are used as coffee substitute and they are
embedded in a mealy pulp sometimes called dozim, that is high in energy
value. They contain up to 29% crude protein and up to 60% saccharose,
rich in Vitamin C and high in oil content. (Ladokun et al., 2013).
The production of condiments is largely
done on a traditional small scale household basis under highly variable
conditions (Odunfa,1985). The fermentation is usually carried out in a
moist solid state, involving contact with appropriate inocula of
assorted microorganisms aided by the temperatures of the tropics. The
desired state of the fermentation of the consents is indicated by the
fermentation of mucilage and overtones of ammonia produced as a result
of the breakdown of amino acids during the fermentation process
(Omafuvbe et al., 2000). The characteristics ammonical odour and flavour
of condiments enhance the taste of food which in which they are used
especially the various soups used as accompaniment to starchy root and
tuber diet (Simmons, 1976).
1.2 Problem Statement
During the Nigerian processing of Iru,
salt is usually added to prevent microbial contamination and growth.
However, inspire of these procedures Iru could still harbour loafs of
microorganisms especially while handling. Hence, there is need to
microbiologically evaluate the Iru in other to be able to ascertain its
safety as a co dent used in food.
1.3 Objectives of the Study
The major objective of the study is the microbiological evelaution of 'Iru' sold in South West Nigeria.
1.4 Research Questions
(1) what is locust bean condiment?
(2) How are they produced?
(3) why the need yo microbiologically evaluate it ?
1.5 Significance of the study
The ultimate aim of eating food is to
derive adequate nutrient and safety of the food. In Nigeria, the
prevalence of food poisoning even though most cases are not reported
demands that particular attention be paid to microbiological evaluation
of food. This study gives a clear insight into the microbiological
evaluation of locust bean condiment (Iru) sold in South West, Nigeria as
it is widely consumed there.
1.6 Scope of the Study
This research focuses on the microbiological evaluation of Iru (locust bean condiment) sold in South West Nigeria.
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