CHAPTER ONE
INTRODUCTION
“Ogiri” is a local condiment inform of oily paste with strong putrial and ammonial odour made from some fermentation vegetable proteins (oil seeds).
It is a popular soup condiment in many parts of Nigeria particularly in Enugu Anambra, Imo,Ondo River states, Benue-plateau states.
“Ogiri” can be in various form such as solid, semi solid (paste) depending on the type of raw material (legeime seed) used in the production of it.
Hwever, when it is in solid form, it can be put into shapes like circlus (flat) triangular and quadrilaterals.
Types of Ogiri are dawadawa “Iru,” “Ogiri, nwan,” “Igba – Apara,” “Ukpaka (ugba)”, “Ogiri – sara” onwuka (2003).
However, “dawadawa” and “Ogiri” are used as condiments in soup, sauce and porridge and ogiri act as soup “dawadawa” and ogiri act as soup condiments as well as food flavour. “Ugba” (ukpaka) is commonly used to suppliment a variety of food in the eastern (especially Anambra and Imo)
States of Nigeria, it is frequently mixed with yam or with tapiocal (Abacha) and also with stock – fish and serve during important ceremonies. Some people even it those flawaring agents raw as they are.
In Nigeria and in some African countries, people who use ogiri as flavouring agent are only concerned in the nutritive value of the ogiri not minding their microbial load. Although a food will not be selected volubility and consumed less it appeals to the consumer in terms of appearance mouth feel and flavour (ogbo V.N (1999). Though ogiri has an un welcoming flavour and an unattractive presentation (ogbou V.M), yet its addition to food as spaces makes the food very palatable.
Most of these condoment used as flavouring agent content vegetable proteins which are usually rich in glutamine and asparagine and these can either be engymatically or chemically hydralysed to glutamic asid and asportic acid by micro – organisms other products of the hydrolysis are Alain Agirine and proline (Obi E.I.2003). The delaminated proteid has a lower iso-electirc point and therefore are are easily soluble in foods systems ogbogu (1999), it has also been reported that levels of deamination as low as 2-6% could enhance the fuctional properties of these ammonacids.
Ihekoronye and Ngoddy (1985) stated that the functional properties of these aminoacids as giving nice flavour to food.
The processing of the oil seeds is still at the traditional level. The procedure differs slightly in different locations.
Most of the leytable protein seeds used in preparational of this traditional condiment logired are castor bean (Ricinus communis), oil bean (pentaclethera macrophylla), sesame seed (sesamum indicum), saya bean (Glycine max) etc.
Some of them which contain toxic substances example Ricin in castor oil beansee trysinhbitor from soya bean are detoxified during processing to avoid an unpleasant effects they cause.
However, castor bean seed cause irritation in the mouth, throat and stomach also vomiting.
Soya bean has a bitter taste and similar processing method such as fermentation, heating and boiling are required prepare them for food use.
Wherever fermentation is involved in processing food, microorganisms are present. The term fermentation is an energy yielding metabolic process that involves the decomposition of carbohydrate in the absences of oxygen.
Loius pastent stated that physiological process permitting certain organism to live and grow in the absence of air is referred to as anaerobic fermentation which in the preserve of oxygen it is called aerobic fermentation. Nweke A.E (1999) reported that fermented foods are those in which their production depend on the activities of microorganism.
Micro-organisms play an important role in modifying the substrates physically, sensory and nutritionally (Aweke 1999).
Members of fermenting organisms are important; for instance, Bacillus and coagulates negotiable the fermented (utrullu vulgarist and)(Ricinus communis) seed in ogiri preparation; Ogbogu (1999) and African oil bean seed in ugba preparation, presopis African for the preparation of okpehi a seasoning agent temper an Indonesian fermented vegetable protein food prepared from soyabean in which Bacilus spp have been found to be responsible for the fermentation.
These organisms have some properties that enable them to ferment these substrate some of these properties are made available by the organisms themselves as metabolic product in the living organisms or as a component of the endotoxin released when the organism is already dead.
Some of them can be protoelytic their action while some lipolytic, others athylolytic ogbogy, V.N. However, they confermed the work of Barber let al the (1987) as he classified Bacillus subtilis which he found in (dawadawa) as being amylolytic in its action.
Thus, the aim of this work is to identify and isolate micro-organisms involved in the fermentation of castor seed bean “ogiri” and the of use the pure isolate in fermentation soyapaste as well as seeing how best the product resemble the already existing ogiri.