Physicochemical and Organoleptic Properties of Wheat-tiger Nut Shaft Cookies
Objective of the Study
The objective of this project is to examine the physicochemical properties of wheat-tigernut cookies.
Wheat (Triticum aestivum)
Wheat is counted among the ‘big three’ cereal crops, with over 600 million tonnes being harvested annually. For example, in 2007, the total world harvest was about 607 m tonnes compared with 652 m tonnes of rice and 785 m tonnes of maize. However, wheat is unrivalled in its range of cultivation, from 67 N in Scandinavia and Russia to 45 S in Argentina, including elevated regions in the tropics and sub-tropics (Feldman, 1995). It is also unrivalled in its range of diversity and the extent to which it has become embedded in the culture and even the religion of diverse societies. Most readers will be aware of the significance of bread in the Judaeo-Christian tradition including the use of matzo (hard flat bread) at the Jewish Passover and of bread to represent the ‘host’ at the Christian Eucharist (Holy Communion). The latter may be a thin unleavened wafer, similar to the Jewish matzo, in the Roman Catholic Church and some
Protestant denominations, or leavened in other Protestant denominations and the Eastern Orthodox Church. But how many readers are aware that bread is treated as sacred in everyday life in the largely Muslim communities of Central Asia, such as Uzbekistan and Kyrgyzstan? In this culture, the leavened round breads (nan) are stamped before baking and must be treated with respect, including being kept upright and never left on the ground or thrown away in public. These customs almost certainly originate from earlier indigenous religions in the Middle East in which wheat played a similar role and was sometimes equated with the sun and its god. Although such cultural and religious traditions are fascinating and will certainly reward further study, they are essentially outside the scope of this article which will examine why wheat has developed and continues to be so successful as a crop and food source.
Origin and Evolution of Wheat
The first cultivation of wheat occurred about 10 000 years ago, as part of the ‘Neolithic Revolution’, which saw a transition from hunting and gathering of food to settled agriculture. These earliest cultivated forms were diploid (genome AA) (einkorn) and tetraploid (genome AABB) (emmer) wheats and their genetic relationships indicate that they originated from the south-eastern part of Turkey (Dubcovsky and Dvorak, 2007). Cultivation spread to the Near East by about 9000 years ago when hexaploid bread wheat made its first appearance (Feldman, 2001). The earliest cultivated forms of wheat were essentially landraces selected by farmers from wild populations, presumably because of their superior yield and other characteristics, an early and clearly non-scientific form of plant breeding! However, domestication was also associated with the selection of genetic traits that separated them from their wild relatives. This domestication syndrome has been discussed in detail by others, but two traits are of sufficient importance to mention here. The first is the loss of shattering of the spike at maturity, which results in seed loss at harvesting. This is clearly an important trait for ensuring seed dispersal in natural populations and the nonshattering trait is determined by mutations at the Br (brittle rachis) locus (Nalam et al., 2006).
The second important trait is the change from hulled forms, in which the glumes adhere tightly to the grain, to free-threshing naked forms. The free forms arose by a dominant mutant at the Q locus which modified the effects of recessive mutations at the Tg (tenacious glume) locus (Jantasuriyarat et al., 2004; Simons et al., 2006; Dubkovsky and Dvorak, 2007). Cultivated forms of diploid, tetraploid, and hexaploid wheat all have a tough rachis apart from the spelt form of bread wheat. Similarly, the early domesticated forms of einkorn, emmer, and spelt are all hulled, whereas modern forms of tetraploid and hexaploid wheat are free-threshing. Whereas einkorn and emmer clearly developed from the domestication of natural populations, bread wheat has only existed in cultivation, having arisen by hybridization of cultivated emmer with the unrelated wild grass Triticum tauschii (also called Aegilops tauschii and Ae. squarosa). This hybridization probably occurred several times independently with the novel hexaploid (genome AABBDD) being selected by farmers for its superior properties. The evolution of modern wheats is illustrated in Fig. 1 which also shows examples of spikes and grain.
MATERIALS AND METHODS
Source of Raw Materials
Wheat and Tigernut were bought from a local market in Owo, Ondo State Nigeria, and other ingredients used for this study were purchased at the same local market Owo. This research work was carried out in Department of Food Science and Technology, Rufus Giwa Polytechnic Owo, Ondo State, Nigeria.
Methods of Preparation
Preparation of wheat flour
For the production of wheat flour, 2kg of wheat was measured after which foreign materials such as dirt’s, stone, cobs, damaged and colored seeds were removed manually by hand picking. The sorted wheat was milled using laboratory attrition mill to produce wheat flour (WF) and was stored in an air tight polythene bag until needed further analysis as shown in figure I.
RESULTS AND DISCUSSION
Table 4.1: Proximate Analysis of biscuit produced from whole wheat-tigernut flour (%).
CONCLUSION AND RECOMMENDATIONS
In terms of overall acceptability, sample A has the highest sensory score, but it does not have any significant different with sample B and C. Inclusion of tigernut flour in wheat flour at levels of 10 to 50% resulted in notable increase in fat contents while ash and fibre content decreased, the protein content also increased thanks to the inclusion of tigernut, which can be used to combat protein malnutrition among children since they love eating biscuits. The carbohydrate content also revealed that all samples are rich in carbohydrate. Evaluation of the nutritional properties of dough from the composite flour and sensory properties of biscuit revealed that a 90% wheat flour substitution with tigernut flour yielded biscuit product that was similarly rated with that produced from pure wheat flour.
This product, most especially at 10% tigernut flour level of substitution is recommended for human consumption. Further studies in these areas include selection of improvise varieties of tigernut and protein supplements such as tigernut as well as optimization of processing conditions for the production of tigernut biscuits and microbiological quality acceptability of the blends could be carried out.
Also, Nigerians should be encouraged to cultivate tigernut based diet to meet their daily nutritional requirements.
- Abano, E.E. and Amoah, K.K. (2011). Effect of moisture content on the physical properties of tigernut (Cyperus esculentus). Asian J. Agric. Res. 5(1):56-66
- Abdel-Aal, E.S.M., Sosulski, F.W. and Hucl, P. (1998): Origins, characteristics and potentials of ancient wheats. Cereal Foods World 43, 708–715.
- Achoribo, E.S. and Ong, M.T. (2017). Tiger nut (Cyperus esculentus): Source of natural anticancer drug? Brief review of existing literature. EuroMediterranean Biomedical Journal, 12(19), 91–94.
- Achoribo, E.S. and Ong, M.T. (2019). Antioxidant screening and cytotoxicity effect of tigernut (Cyperus esculentus) extracts on some selected cancer-origin cell lines. Euromediterranean Biomedical Journal, 14(1), 1–6.
- Adama, K.K.., Afolayan, M.O., Oberafo, A.A. and Thomas, S. (2014). Isolation and physicochemical characterization of tigernut (Cyperus esculentus) starch as a potential industrial biomaterial. Int. J. Mat. Sci. Appli. 3(2):37-41
- Adams, M.L., Lombi, E., Zhao, F.J. and McGrath, S.P. (2002). Evidence of low selenium concentrations in UK bread-making wheat grain. Journal of the Science of Food and Agriculture 82, 1160–1165.
- Adebayo, S.F. and Arinola, S.O. (2017). Effect of Germination on the Nutrient and Antioxidant Properties of Tigernut (Cyperus esculentus). Journal of Biology, Agriculture and Healthcare, 7(18), 88–94.