The long search for Ghana to add value to waste by turning it into profit making ventures, is yielding good results and the agriculture sector had shown the way by focusing on yam and cassava residue.
Thanks to the Gains from Losses of Root and Tuber Crops (GRATITUDE), the country has instituted measures to ensure that roots and tuber crops like yam and cassava which suffer between 30-60 per cent post-harvest losses are reversed and sustained.
The GRATITUDE project preliminary study has revealed that yam and cassava peels can be used as alternative substrate for cultivating quality mushroom.
The European Union funded project is on the theme: “Reducing Post – Harvest losses for increased security.”
About 50 per cent of cassava produced are utilised fresh while the rest are processed into various cassava related product.
Findings show that over 90 per cent of the peels are either burnt or left unattended to at dumping sites.
In the case of yams, waste is mostly generated at the consumption level through households, chop bars and food vendors.
Since yam processing is very limited, it is done by a few small and medium enterprises.
Yam peels constitute about 14 per cent of the volume of yam consumed and approximately five per cent of volumes of the crop traded to go waste.
The report said peels and other parts mixed generated at the processing centres ranged from 25-32 per cent of total cassava.
A total of 3.6 million tonnes of cassava waste peels and discharged parts during the peeling process are generated annually.
Peels represents around two third of the waste. About 200,000 tonnes of cassava can be saved through more efficient peeling which translates into potential savings of almost $37 million.
Peels are generated during the processing of gari, agbelima, kokonte and high quality cassava flour and consumption of the crop.
Currently, less than 10 per cent of the peels generated at the processing level are utilised for animal feed while other wastes generated from cassava including leaves and stems are fermented among other alternatives.
However, a shift from over dependence on wild mushroom to the consumption of cultivated products presents enormous opportunities for mushroom growers and subsequently cassava and yam farmers.
There is a growing demand for valued added organic products, especially in the hospitality industry like hotels and restaurants as well as the exports sector.
According to Mrs Mary Obodai, a mushroom expert at the Food Research Institute, mushroom cultivation has become very important because of the growing health consciousness of consumers.
It also generates employment opportunities, augments government’s policies on agri-business and facilitates entrepreneurial development.
Mushroom is said to have a high nutritive and medicinal value. It has high source of protein, mineral and vitamins and the capacity to convert nutritional valueless substances into high protein food.
It is recommended that cassava peels should be composited before being used for the cultivation of mushroom.
After the production of mushroom, the spent substrate, which is rich in nutrients, can be used to prepare feed for poultry and small ruminants and bio-fertilizer for crop cultivation.
Opportunities in the cassava industry identified include improved and more convenient versions of traditional processed products, such as of cassava flour (low quality cassava flour) as import substitutes for plywood and paperboard adhesives.
There are also potential markets for cassava products in the production of sweeteners, mosquito coils and the brewing industry.
Other probabilities includes the use of improved technologies such as mechanised flash, rotary and bin dryers, mechanised peeling, improvement in sun-drying and recycling from dewatering in addition to the use of waste and peels for mushroom production and animal feed.
Cassava, yam and other roots and tuber crops are increasingly becoming important in the food systems of many developing countries and food security crops for about 700 million people in Sub-Saharan Africa.
With root and tuber crops production steadily increasing from 688 metric tonnes in 2001 to 740 million tonnes in 2007, and the world’s production of cassava 228 metric tonnes and yam at metric tonnes, the crops could become a viable panacea to poverty alleviation and food security in developing countries.
By Audrey Dekalu