ABSTRACT
The
effect of Okara and Detarium microcarpum
seed flours on the quality of talia noddles produced from wheat and sorghum
flour composites was investigated. Composites of wheat semolina/sorghum flour
blended in ratio of 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50 were prepared
and evaluated for water absorption capacity, soluble solids and swelling
capacity. Cold extruded talia produced from each flour composites dough was
evaluated for cooking time, cooking losses and total organic matter. The 100:0,
90:10, 80:20 and 70:30 wheat semolina/sorghum flour composites were selectedand blended with different levels
(0-20) % of Okara and Detarium
microcarpum flours, evaluated for physico-chemical properties and talia
produced from the flour blends were evaluated for cooking test and sensory
qualities. Four best talia products were selected, stored for six months (30 ±
2oC, 85±5% RH) and evaluated for pH, moisture content, TBA number
and mould count. Presence of sorghum in the composite flour increased the water
absorption capacity from 7.33% to 12.33%, decreased swelling capacity from
52.0% to 45.4%, while talia made from the composites showed increased cooking
loss (0.14% to 0.82%), total organic matter (1.26 to 2.84) and reduced radial expansion
(3.0 to 2.0) relative to the control. Sorghum addition at 30% level was
acceptable for talia production based on low water absorption capacity and high
swelling capacity. Okara addition increased the protein content (from 10.21% to
13.63%) of the composites and talia. Blends with 10% okara showed low water
absorption capacity (12.75%), low cooking losses (0.73%) and high scores in all
the sensory attributes except in appearance but differed significantly (p <
0.05) from the control (100% wheat). Detarium
microcarpum addition increased the crude fibre (from 1.69% to 3.76%)
content of the talia. There was no significant (p > 0.05) difference among
samples at 5% levels of Deterium
microcaprum incorporation relative
to the control in all the sensory attributes except in appearance. Low water
absorption capacity, cooking loss, and optimal total organic matter (2.01) were
observed in the samples at 5% level of Detarium
microcarpum incorporation. Okara and Detarium
microcarpum addition into talia increased the total dietary fibre contents
(from 8.61±0.02% to 9.97±0.01%). The total dietary fibre and mineral contents
of samples differed significantly (p < 0.05) with the control. Moisture
contents and TBA number did not differ (p>0.05) among stored samples but pH
and mould count differed (p < 0.05) relative to the control. Low values of
TBA (0.6 to 3.17 mg malonaldehyde/kg sample), mould count (0 to 1.4 x 102
cfu/100g) and moisture contents (10.5% to 14.5%) were recorded during storage.
CHAPTER ONE
INTRODUCITON
1.1 Background
‘Talia’ is a Hausa name for pasta (noodles). It consists of thin ribbons or strips of dough locally made from durum wheat semolina and other cereals using manual cold extrusion and drying. ‘Talia’ was probably introduced into Kano many centuries through Trans Saharan Mediterranean trade (Anon, 2012c). The word ‘talia’ was derived from the Italian Pasta called tagliatelle, a type of pasta from Emilia-Romagna and Marches, region of Italy. Individual pieces of tagliatelle are long flat ribbons that are similar in shape to fettuccine and are typically about 0.6cm to 1cm diameter (Italian trade commission, 2009). According to Italian trade commission (2009), tagliatelle was created by a talented court chef, who was inspired by Lucrezia of Este’s hairdo on the occasion of her marriage to Annibale II Bentivoglio in 1487. The recipe was called tagliolini di pasta esugo, alla maniera di zafiran (meaning tagliolini of pasta and sauce in the manner of Zafiran) and tagliatelle has since then become a more common food. ‘Talia’ is a common staple consumed by a large section of the rural poor in northern Nigeria. It can be prepared with other ingredients like tomatoes, oil, and meat/fish, in the form of ‘Jollof’ or white cooked with groundnut oil and spices. The later is the most commonly served due to economic reasons. Apart from being prepared and eaten in the homes, ‘talia’ is also hawked around schools and market places as street or fast foods. Recent advances in the manufacturing and processing of pasta (noodles) did not have much effect on the consumption rate of ‘talia’ among the Northern natives, probably because ‘talia’ is generally affordable (Anon, 2012c). ‘Talia’ being a cereal based product, has high carbohydrate content (65%) and low protein content (9%) (USDA, 1974).
According to Giese (1992), the nutritional content of pasta is widely based on the ingredients used in its preparation and added sauces. Limiting nutrients in pasta can be augmented by adding foods rich in such nutrients to the base ingredients (wheat semolina) otherwise known as food to food fortification. Wu et al. (2001) reported increase in protein content of spaghetti fortified with corn gluten meal. There was an increase in protein content of macaroni (12.1%-14.2%) when substituted with cellulose-protein complexes (Oifat et al., 1993). Stefania et al. (2010) recorded increase in protein content of semolina spaghetti with legume flour. Most staple foods of the Northern rural poor are cereal based. These include ‘talia’ ‘tuwo’ ‘masa’, ‘sinasir’, ndaleyi’, ‘madidi’, ‘capa’among others. Talia a cereal based food is limiting in protein and dietary fibre. To improve the protein and dietary fibre contents of talia therefore, there is need to incorporate foods rich in these nutrients into talia. Okara, a by-product of the soymilk industries, but rich in protein (24%) according to Rinaldi et al.(2000), Glutamic acid (0.57g), Aspartic acid (0.36g) and Lysine (0.212g) as recorded by Anon (2015) and Detarium microcarpum an indigenous legume and a good source of soluble dietary fibre (50g per 100g dry matter)(Ene-Obong and Carnovoule,1982), can be added to the base ingredients to produce enriched ‘talia’ thus addressing these nutrients’ deficiencies.
Composite flour technologies initially refer to the process of mixing wheat flour with other cereals and legume flours for making bread and biscuit. However, the term can also be used in regard to mixing of non-wheat flours, roots and tubers, legumes or other raw materials (Dendy, 1992). Blending wheat flour with locally available cereal and root crops would be desirable to encourage the agricultural sector and reduce wheat importation in many developing countries. In Africa, there has been an ever-increasing demand for wheat products such as bread and pasta. Africa is not a major wheat-growing region, but produces large quantities of other cereals such as sorghum and millets. It has been reported that replacing wheat with 20% or 30% non wheat flour for bakery products would result in an annual estimated savings in foreign currency of US $320 million and US $480 million respectively (FAO, 1982). In addition, nutritional enhancement is another goal that is frequently addressed in the development of flour blends.
Thus, composite flour technology holds excellent promise for developing countries. Although, actual consumer trials have been rare, products made with composite flour have been well accepted in Nigeria, Kenya, Colombia, Senegal, Sri Lanka and Sudan (Dendy, 1992). Sorghum is one of the lesser used cereal in Nigeria. Sorghum is gluten free and the starch contains 100% amylopectin. These make sorghum a good substitute for wheat flour (Miche et al., 1977). Therefore, this work seeks to determine the optimal level of wheat substitution with sorghum, okara, and Detarium microcarpum flours in formulating acceptable ‘talia’ pasta.
1.2 Statement of the Problem
Northern Nigeria has the highest prevalence of malnutrition in the country. More than half a million children in Northern Nigeria faced severe malnutrition in 2013(Anon, 2013). Malnutrition remains an underlying factor in about one third of Nigerian child deaths and communities in the northern parts are among the worst affected (Anon, 2011). ‘Talia’, which is deficient in protein and dietary fibre, is majorly consumed by the rural poor. These people cannot afford the high cost of animal protein and are consequently vulnerable to malnutrition. There is therefore a need to increase the protein content of ‘talia’ which is a staple for these rural communities using affordable plant sources. It is also interesting to note that these rural communities produce soymilk and discard the ‘Okara’ (‘Dutsan-soya’ in Hausa)or use it as animal feed. Incorporating this protein rich waste into talia will address this protein deficiency associated with Talia.
Secondly, the high moisture content (80%) of ‘okara’, makes it difficult to handle and too expensive to dry by traditional or conventional means. Many people therefore dispose it on land (land fill). Discarding ‘okara’ as waste on land constitutes an environmental problem (pollution), because ‘okara’ is highly susceptible to putrefaction and produces bad odour (Rinaldi et al., 2000). Incorporating ‘okara’ into ‘talia’ could help to eliminate a possible source of pollution while at the same time adding economic value to this waste product.
High cholesterol in foods has led to several health conditions such as coronary heart disease, cancer, high blood pressure and obesity among other health conditions. Fibre in diet plays very significant roles as certain physiological responses have been associated with the consumption of dietary fibre. Such roles include increase in faecal bulk and lowering of plasma cholesterol (Ene-Obong and Carnovoule, 1982). Pederson et al. (1980) observed that the supplementation of the diets of diabetic patients or those with impaired glucose tolerance with dietary fibre resulted in an improvement in blood glucose profiles and reduction in urinary glucose. Lack of dietary fibre is one of the problems of food products like ‘talia. Incorporating Detarium microcarpum, a good source of dietary fibre into ‘talia’ could address dietary fibre deficiency in talia.
Nigeria is not a wheat-growing region, but it produces large quantities of other cereals such as sorghum and millets. Blending sorghum flour and wheat semolina for ‘talia’ production could encourage the agricultural sector, reduce wheat importation and promote the use of indigenous crops within and outside the country.
1.3 Justification of Study
The high prevalence of malnutrition among the rural communities in northern Nigeria is a major concern. The idea of re-channeling the waste protein in ‘okara’ to the food chain for human consumption could address malnutrition, reduce a possible source of environmental pollution, add economic value to the waste product, and create job opportunities leading to better socio-economic development in the country.
Increasing dietary fibre in diets can help increase faecal bulk and lower plasma cholesterol (Ene-Obong and Carnovoule, 1982). Incorporating Detarium microcarpum in talia could improve its dietary fibre content and hence reduce the risk of chronic diseases.
1.4 General Objective
The broad objective of the study was to evaluate the quality of ‘Talia’ supplemented with sorghum, okara and Detarium microcarpum.
1.5 Specific Objectives
The specific objectives of the study were:
- To produce wheat- sorghum flour blends and determine the proximate and functional properties,
- To incorporate okara and Detarium microcarpum into wheat / sorghum flour blends and determine physico-chemical properties,
- To produce talia with the flour blends,
- To determine the storage stability, chemical and microbiological qualities of talia.
