Food Condiments – Minerals in Some Nigerian, African Vegetables
FOOD CONDIMENTS – MINERALS IN SOME NIGERIAN, AFRICAN VEGETABLES
Evaluation of Minerals in some Nigerian food condiments, Ogiri Egusi, Ogiri Ugba, Uda, Uziza, Okpei, Dawadawa and more.
In sub- Saharan Africa, fermented vegetable proteins are use as flavoring agents is soups and sauces. Apart from their strong and pleasing aroma, they also contribute to the protein and essential fatty acid intake.
Fermentation of these vegetable proteins is usually done in the moist solid state by random inoculation brought about by various indigenous species of micro organisms.
In Nigeria, some of the commonly used condiments are (ogiri egusi) form melon seed, (iru) from African locust beans, (ogiri ugba) from African oil bean seeds, ( dawadawa) from soy beans etc..
Although micro organisms that have been implicated in the fermentation processes of the above condiments are diverse and frequently unpredictable, there seems to be a general agreement on the predominance of the spore- forming bacteria species, especially bacillus as the main fermenting agent. The proximate composition indicates that (iru) and ( ogiri egusi) were widely used to give flavor and tastes to food and could contribute to the protein, lipid and mineral daily intake when used liberally as done is several homes, where the expensive animal product is a luxury (odunfa 1981: 1985) (Omafavbe et al, 2000, 2002).
The objective of this study is to evaluate the mineral composition of some Nigeria condiments such as Ogiri egusi, Ogiri ugba, Okpei, Uda, Uziza, Dawadawa.
2.0 INTRODUCTION TO UZIZA
Spices generally are part of various plants cultivated for their aromatic pungent or otherwise desirable substances. Spices consist of rhizomes, bulbs, barks, flower buds, stigmas, fruit, seeds and leaves. They a re categorized into tiny wild fruits, nuts, herbs, spices and leafy vegetables. Some of them were not only used for food, but for medicine in minor ailments by the natives. On dry weight basis the crude protein content ranged from 4.6 to 22.1 percent for spices and herbs, 3.2 to 43. 1 percent for fruits and nuts,15.9 to 35.7 percent fro leafy vegetables.
2.1 HISTORICAL BACKGROUND OF UZIZA
West African pepper, also known as Ashanti pepper, Benin pepper, false cubebs, Guinea cubebs, Uziza pepper or (ambiguously) “Guinea pepper”, called locally kale, kukauzabe, masoro, sasema and sorowisa, is West African spice that corresponds to the dried fruit of piper Guineense.
The plants that provide Ashanti pepper are climbing vines that can grow up to 20m in length in Western African and are Semi-cultivated in countries such as Nigeria where the leaves (known as Uziza) are used as a flavoring for stews. Ashanti peppers contain 5-8% of the chemical significant proportion (10%) of myristicin, elemicin, safrole and dillapoil.
In term of flavor, Ashanti pepper is very similar is cubeb pepper but is much less bitter and has a fresher more herbaceous flavor. Though known in Europe during the middle ages (it was a common spice is Roven and Dieppe in 14th century, France), these days the use is marginalized of west and central African.
2.2 ECONOMIC VALUE OF UZIZA
Healthy living is a lifestyle that requires good planning. Washing the body and mouth is the morning is refreshing.
There are too many leaves that cure and which constitute vegetable we can put into our food while cooking. The first leaves or vegetables to be introduced are Uziza which is the native name. Uziza is called piper guinenses in biological notation. The use of Uziza is very rampant though little is known of its importance in our daily cure and sickness prevention. The vegetable used to coo pepper soup, uziza helps a lot to prevent allergy and running nose. Most doctors do not like the idea of traditional medication because it will not give them the opportunity to make money from insurance companies. The Uziza leaves keeps the body warm and prevent cold.
2.3 CHEMICAL COMPOSITION OF UZIZA
Thiny wild fruits, nuts, herbs, spices and leafy vegetables were characterized and their chemical composition determined. Results on dry weight basis the crude protein content ranged from 4.6 to 22.1 percent for spices and herbs, 3.2 to 43.1 percent for fruit and nuts and 15.9 to 35.7 percent for leafy vegetables. The fat (either extract) ranged from 7.5 to 36.0 percent for spices and herbs, 18 to 72. 6 percent for fruits and nuts and 10.6 to 22.6 percent for leafy vegetables. Total carbon-hydrates content ranged from 34.6 to 71.9 percent for species and herbs, 11.3 to 76.1 percent for fruit and nuts and 24.6 to 51.4 percent for leafy vegetables. The wild fruits, nuts and leafy vegetables are high in ascorbic acid (vitamin c).
Ascorbic acid content ranged from 18mg 1100g dry sample to 113mg/100g sample for fruits and nuts and 23mg/100g 232mg/100g sample for leafy vegetables. The level for peroxide value and free fatty acids (as percent oleic acid) of the spices are generally low indicating good storage stability of these plant materials. The flavor imparting essential oils (as percent oleoresin) content of the spices/ herbs were fairly high and ranged from 0.1 to 5.2 percent.
In Nigeria, many fruits, spices, herbs and leafy vegetables used as food are obtained from the wild where there may be as many as one thousand species. To date, little attempt has been made to domesticate and cultivate those species despite the fact that they constitute a large proportion of the daily diet of the rural dwellers. The implication is that several of these species could become extinct due to deforestation menace and the reluctant of people to venture into the forest and to harvest them. The net result is that some of these crops such as ‘utazi” (Gongronema ratifotia) ‘’uziza” (pipper guinense). This could also be equated to “farming process“.
Indigenous spices and herbs are use generally to prepare pepper soups which are hot and spicy especially during the cold season.
2.4 TRADITIONAL FERMENTED CONDIMENTS (DAWADAW, OGIRI)
Traditional diets in west Africa often lack variety consist of large quantities of the staple food (cassava, yam, maize) with supplements of plantains cocoyam, rice and beans depending on availability and season (Achi 1999). Soups eaten with the staples are an essential component of the diet and may contain a variety of seeds, nuts, pulses, and leaves (amp-bell plan 1980) the staple provides the calories but are poor in “other nutrient“. Soups are the main sources of proteins and mineral and one of the ways to the diet have been to improve the nutrient content of soup.
Seeds and legumes may account for up to 80% of dietary protein and may be the only source of protein for some groups. Their cooked forms are eaten as meals and are commonly used in fermented form as condiments to enhance the flavor of foods (Odunfa 1985c: Aidoo 1986: Achi 1991: Onionflok 1996). With high content of protein, legumes condiments can serve as a tasty compliment to sauces and soups and can substitute for fish or meat.
The food flavoring condiments are prepared by traditional methods of uncontrolled solid substrate fermentation resulting in extensive hydrolysis of the protein and carbohydrate component (Fatugo et al, 1973: Eka 1980). A part from increasing the shelf life and a reduction in the anti- nutritional factors (Odunfa 1985b: Reddy & Pierson, 1999: Barimalaa et al, 1989: Achi & Okereka, 1999). Fermentation markedly improves the digestibility, nutritive value and flavors of the raw seed.
Although fermented food condiments have constituted a significant proportion of the diet of many people Nigerians have exhibited an ambivalent attitude in terms of consumer tastes and preference for such foods (Achi 2005). The introduction of foreign high “technology products” especially processed ones because of globalization and liberalization of the economy radically changes the Nigerian food culture into a mixed grill of both foreign and local dishes (Ojo, 1991). Many developing countries are still preparing traditional fermentation products for human consumption (Campbell platt 1987.)
Fermented products remain of interest since they do not require refrigeration during distribution and storage. The traditional condiments have not attained commercial status due to the very short shelf life, objectionable packaging materials, stickiness and the characteristic putrid odour (Arogba et al, 1995). Fermented condiments often have a stigma attached to them; they are often considered as food for the poor.
The production of fermented vegetable proteins for use as food condiments is craft based. Remarkably, in many areas of Nigerian today they are still made in traditional ways, with success depending upon observance of good manufacturing practices and control of environmental conditions during the manufacturing phase. Starter cultures are not normally used and therefore variations in the quality and stability of the products are often observed.
NAMES AND SUBSTRATES OF FERMENTED CONDIMENT
Throughout Nigeria, many names are applied to the multitude of fermented food condiments. Table 1 show the variety of name by which the product are known in different parts of the country. The exact origin of such name could be attributed to
a. The region or area of manufacture
b. The type of legume or oil seed used and
c. The spelling according to region or area.
The Yoruba’s of the southwestern Nigeria locally call fermented condiments ‘Iru’ while Hausas who inhabit most of the northern part of Nigeria call it dawadwa. Ogiri is the name used by the Igbo’s of the southeastern Nigeria. Similarly, Okpiye is popular name among the Igala and Idoma people of the middle belt region.
The conventional substrates for condiment production are diverse and each can be produced from more than one material. Almost any edible plant material can be subjected to fermentation. Judging by the available literature over nine different fermented products are condiments.
2.5 IMPORTANT MICROORGANISMS FOUND IN FERMENTED CONDIMENTS AFTER DIFFERENT PERIOD OF FERMENTATION.
BASICS OF MANUFACTURING PROGRESSES
The methods employed in the manufacture of fermented condiment differ from one region to another because these progresses are based on traditional system, some of which are summarized in table 2. A basic scheme of vegetable fermentation for production o condiments is depicted in figure 1. According to local custom, climate, condition and the type of substances used, specific process variation occur. In general, fermentation takes place under appropriate growth and activity of the microorganisms.
Traditionally, raw beans are cooked for upward of 12hrs in excess water until they are very soft to allow for hand de-hulling. The length of time of cooking depends on the strength of the taster on the de-hulling efficiency of the seeds (Parkia bigobos) can be cooked for 8-12hours ( Oyewole and Odunfa, 1990), though prosopis Africana can be cooked for 5-6hours (Achi, 1992). Boiling in 0.1m Na2Co3 reduces the cooking time to 4hrs and increases the de-hulling efficiency to 89% (Achi and Okereka, 1999). While Telfair seeds require minor cooking for 30 to 60mins, citurllus vulgaris and castor seeds are de-shelled before cooking.
At present, most de-hulling processes rely on the tedious method of hand separation. Abrasive de-hulling of dry beans of Parkia or Prosopis is not possible because of the strong adherence of hulls to the seeds. Nevertheless as a techniques for effecting reduction in cooking time (Yabo et al., 2000). Boiling in excess water serves not only the purpose of partial cooking, but facilitates microbial penetration and human digestion. The butter and beany taste of soybean disappears in less than 15mins at 90oc (Nout et al., 1985). After cooking and de-hulling processes have been completed, the cotyledons are prepared for fermentation. For some seeds, such as African oil bean (pentaclethra macrophylla), the cotyledons may be boiled again from 1-2hrs. A soften agent ‘kauri’ (potassium carbonate) may be added to aid-softening of the cotyledons (Odunfa, 1985c; Ikenebomeh, et al, 1986).
NUTRITIONAL QUALITY OF FERMENTED CONDIMENTS
Classical techniques for assessment of bioavailability of nutrients generally involve in vitro tests with animals. Protein utilization measured as protein efficiency ratio (PER) and the digestibility of soybean and some legume are hardly improved by fermented soybean any better than from the cooked substrate. Nevertheless, some reports indicate otherwise. Achinewhu (1983) reported that fermentation and heat treatment improved apparent digestibility, feed conversion efficiency and protein efficiency ration when rats were fed on diets of African oil bean seeds rations.
Eka (1980) studied the effect of fermentation on the nutrient content or locust beans and reported that protein and fat increased when fermented whereas the quantity of carbohydrates decreased. Increased levels of the amino acids were also reported except for arginine, leucine and phenylaarire. Similar results were reported for other seeds legumes (Odunfa, 1985b; Achinewhu, 1988; Sakar et al., 1988). Soluble product increase during fermented product. Alanine, lysine and glutamic acid were the predominant amino acids with arginine and proline occurring in small amounts (Odunfa, 1983a; Aidoo, 1986). The improved nutritive values were attributed to the increase in amino acid profiles due to fermentation.
Food condiments made from vegetable protein may be a good source of certain B vitamins, but are deficient in ascorbate and some fat-soluble vitamins, which are lost during fermentation. Achinewhu and Ryley (1986) have shown that fermentation significantly increased the content of thiamine, riboflavin and niacin in African oil bean. Similar changes were observed during the fermentation of melon seed (Achineqhu, 1986a, b). Ogbonna et.al (2001) Observed increase in calcuim, phosphorus and potassium when African yam bean was fermented for condiment production.
The Nigeria food condiments are known to supply the needed minerals which are very important for human health and they are the most affordable source f minerals to Africans (Akwaowo et al 2002)
Form the table, it was observed that the iron content of some condiments were found to be within the range of (0.6mg/l-0.04mg/l) which is significantly different (P>0.05).
According to (P.M Gaman and K.B Sherrington), the content of Iron in human body is 4.0g, Iron serves as a carrier of oxygen to the tissues from the lungs by red blood cell haemoglobin as a transport medium for electrons within cells, and as integrated part of important enzyme systems in various tissues. The average iron content intake per day in human body system for male 18years and above is (1.05-1.37mg/day) (world health organization and food and agriculture of the United Nations 2004)
It was observed from the date that the highest concentration sodium is 0.032mg/l in ogiri ugba and lowest in dawadawa 0.008mg/l and the concentration differ significantly (p>0.05). The average sodium intake in the human body is 5-20g.
From the table it was observed that the iodine content of some condiments were within the range of (0.950|mg|L-2.53mg|L) which is significantly different (p>0.05). Iodine in the human body is by the action of thyroid hormones in the thyroid gland. The iodine content of food depends on the iodine content of the soil in which it is grown. Comparing the result of the iodine with other minerals analyzed, iodine has the highest range which is (0.95mg/L -2.5399mg|L), zinc (0.049mg|L- 0.016mg|L), potassium (0.032mg|L -0.007mg|L) sodium (0.032mg|L -0.008mg|) while iron has the range of (0.6mg|L- 0.04mg|L).The average iodine content of food (fresh and dry basis) as reported by (koutras et al), fresh basis (mean 30) (range 23-36mg/l), dry basis (mean 234) (range223-245mg/l). The daily intake of iodine recommended by the (food and Nutrition Board of United States “National Development” Academy of Science 1989) for adults are 2ug/kg/day.
These amounts are proposed to allow normal thyroxine (T4) production without stressing the thyroid iodated trapping mechanisms or raising thyroid stimulating hormone (TSH) levels.
Form the table it was observed that the zinc content of some condiments were range from the value of (0.049mg/l-0.016mg/L), according to the result of the analysis, the condiments have the second highest value after iodine which signifies that some of these condiments contains zinc more than the other minerals.
According the (world health organization and food and agriculture organization of the united nation 2004), the total zinc content of the body has been estimated to 30mmol (2g).
From the table it was observed that potassium content of the condiments ranges from (0.032mg/l-0.007mg/l) which differ significantly (P>0.05). It is thought that taking fairly high intake of potassium may counteract the effect of high sodium (salt) intake and reduce the likelihood of developing high blood pressure. Current guidelines, therefore recommend increase potassium intake in adults from an average of 3g to 3.5g per day. (P.M Gaman and K.B Sherrington).
Conclusively, the result from the work revealed that iodine content of some condiments was found to have the highest value, Uziza 2.5399mg/l, Dawadawa 1.2625mg/l ogiri ugba 1.1642mg/l, ogiri egusi 1.058mg/l Okpie and uda has the same value of 0.9501mg/l, while some condiments in Iron has the lowest value, Uziza 0.06mg/l uda, 0.6mg/l, okpei 0.5mg/l, ogiri egusi 0.07mg/l, dawadawa 0.066mg/l, ogiri ugba 0.04mg/l.
Some of these Nigeria food condiment are good to the body because they contains mineral which are very essential in the body system.
FOOD CONDIMENTS – MINERALS IN SOME NIGERIAN, AFRICAN VEGETABLES