Food Science and Technology Project Topics

Effect of Fermenting Containers on the Physicochemical and Sensory Qualities of Garri

Effect of Fermenting Containers on the Physicochemical and Sensory Qualities of Garri

Effect of Fermenting Containers on the Physicochemical and Sensory Qualities of Garri

Chapter One

The Objective of the Study

The objective of this study is to evaluate the effect of fermenting containers on the physicochemical and sensory properties of garri.



  Cassava (Manihot esculenta Crantz)

Cassava (Manihot esculenta Crantz) is the most perishable of roots and tubers and can deteriorate within two or three days after harvesting. It is one of the most important staple food crops grown in the tropical Africa, and plays a major role in effort to alleviate African food crisis because of its efficient production of food energy, year-round availability, tolerance to extreme stress conditions, and suitability to present farming and food system in Africa (Cardoso et al., 2005).

 Taxonomy and Classification of Cassava

There is a wide range of cassava varieties which constitute the sweet and bitter cassava varieties. The designation of bitter and sweet varieties depends on taste that is associated with the levels of cyanogenic glucosides mainly linamarin.  The bitter cassava (Manihot utilissima) has high level of hydrogen cyanide, evenly distributed through the root, which can amount up to 250mg/kg fresh root. It is easily recognized first by its green leaf-stalk and the whitish outer cortical layer of the root (Sirtunga et al., 2004). It also has a vegetation period of 12-18 months.

The sweet cassava (Manihot palmata) is known by a red leaf stalk and purplish outer cortical layer. In the sweet cassava, the hydrocyanic acid is confined to the skin and outerlayer of the root. It’s vegetation period is relatively short usually between 6-9 months (Dulcer et al., 2008).

History and Economic Impact of Cassava

Cassava (Manihot esculenta Crantz) originated in the Northeast Brazil and Paraguay, and was later assimilated by the West Indians (Cardoso et al., 2004). Having begun with these regions, cassava is now cultivated in all tropical regions of the world among which Nigeria is one of them.

Nigeria’s cassava production is by far the largest in the world, three times more than the production in Brazil and almost double the production in Indonesia and Thailand (FAO, 2006). In 2002, the Food and Agricultural Organization of the United Nation in Rome estimated cassava production in Nigeria to be approximately 34million tonnes which on comparison with other crops ranks first, followed by yam production  27million tonnes, sorghum  7million tonnes, millet  6million tonnes and rice  5million tonnes (FAO, 2006).

In Nigeria, cassava appears to be the major staple food that matches the population growth. It is a major source of dietary energy for low-income consumers. It also plays a role in providing a stable food base in areas prone to drought and famine. Cassava is predominantly used as food with small amount in agro-allied industrial livestock feed and starch production (Sanni, 2005).

Many traditional foods are processed from cassava roots among which are; flour, dried chips, garri, fufu, farinha, etc. Cassava starch is extensively utilized by most of the food industries to produce; baked products, confectioneries, canned fruits, jam, preserves, monosodium glutamate (MSG), production of commercial caramel, glucose, dextrose, dried yeast, etc. Non-food uses of cassava starch include; corrugated cardboard, remoistening gum, wall paper industry, textile industry and wood furniture (Moorthy, 2005). Harvesting and transporting of roots from farm to homestead and subsequent processing are mainly done by women. Most of the steps in processing are carried out manually using simple and inexpensive tools and equipment that are available to small farmers. Cassava processing is labour intensive and productivity is usually very low. Transport of products to markets is made difficult by the poor condition of rural roads. The drudgery associated with traditional processing is enormous and the products from traditional processing methods are often contaminated with undesirable extraneous matter. Some of the products are therefore not hygienic and so are of poor market value.  Better processing methods can improve the life-styles and health of rural people through higher processing efficiency, labour saving and reduced drudgery, all of which improve the quality of products.




 Materials Source

Freshly harvested cassava roots were obtained from a staff farm at Rufus Giwa Polytechnic, Owo, Ondo State.

 Preparation of Garri

Preparation of garri from cassava roots

Fresh cassava roots were peeled, washed and cut into smaller pieces for grating. The cassava was then grated using cassava grating machine into cassava mash. The grated cassava was then divided into three parts, the first part was packed inside an iron bucket, it was covered for two days for fermentation while the second cassava mash was packed inside a rubber bucket for fermentation for two days. After fermentation both fermented cassava mash was bagged and pressed. The pulp was then sieved and roasted with a garri roasting pan until desire taste was reached; this was also done to reduce the moisture content down to 1.5% as shown in figure 1 and 2 respectively.




Table 4.1: Proximate composition and energy value of Garri fermented inside three types of containers





The results obtained showed that there were slight increase in protein, ash and fat content in the garri samples fermented using plastic and iron bucket compared to the garri fermented in hessian sack. The fermentation of cassava mash in these containers showed slight difference in their functional and sensory characteristics, therby, the fermenting containers improved the characteristics of the garri slightly. the lack of quality control in these processes will to a large extent affect the final product that the type of fermenting containers used during fermentation.


The fermenting containers for Garri production have the slight effect on the physiochemical and sensory characteristics of Garri but adequate hygienic practice in the production and packaging is essential to produce high quality Garri for consumers. It is recommended that Garri production should fully mechanized and controlled to ensure hygienic production.


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