Yam is a plant cultivated for the consumption of its edible starchy tubers. Yam is a very popular meal in Nigeria. In modern times, high technology now exists that can be used to control the level of humidity and other climatic conditions. However, many farmers in these parts cannot afford such high technology storage systems. Hence, storage and preservation rates are very low. Infestation from insects and pests account for the major losses of yams recorded by farmers in Nigeria. This article teaches how to preserve yam, both at home and for the farmer, after harvest.
How to Preserve Yam in Nigeria
In Nigeria, yams are typically harvested by hand method, using sticks, spades or diggers. At this stage, the farmer must be extra careful so as to avoid damaging the tuber. Once a yam tuber is damaged, it will not store well and its decay will be rapid. If we had a more mechanized form of farming in Nigeria, this would make some of the hurdles faced by small scale rural farmers easier to avoid. Yields will improve as fewer tubers will be damaged. Roots and tubers such as yam are similar to living organisms. After storage, they continue to go through a respiration process. Hence, the dry matter of the tuber continues to be reduced. This is because the starch contained in the cells of the tuber starts to convert into water, carbon dioxide and heat energy. Yam farmers understand this, therefore only sound, healthy tubers are stored.
This is why harvesting of yams have to be done with great care. However, because of the varying sizes and shapes of yam tubers, some damage inevitably occurs. This is also the reason farmers reject unhealthy or damaged tubers or make sure they are consumed or processed immediately.
When yam is damaged or bruised, there is a more likely chance to have decay when in storage. It is best to cut away any bruised or decayed flesh or rub it with alkaline material such as lime or wood ash to discourage infection.
Preserving yam tubers at home
Even though yam is regarded as the least perishable of all tubers, many complain of how quickly yam spoils. Successful preservation of yams requires the following processes:
- An initial selection of sound and healthy yams
You must make sure you buy yams that are healthy in the first place
- Yams must be properly treated. This process is known as curing.
- Proper ventilation to allow for air and escape of the heat generated by respiration and close contact of the tubers
- Regular inspection during storage
- Remove yams that are decaying so they do not contaminate the other healthy ones
- Protection from direct sunlight and rain.
Storing yam at low temperatures that is cool regions help to reduce the respiration rates. It also helps to preserve the yam longer. However, when the temperature is too low, it could cause damage to the yam. The excess cold could cause a breakdown of internal tissues of the yam and then increase loss of water. This would then speed up the yam’s susceptibility to decay. When yams are stored in cold places, the symptoms are not immediately obvious until you move them to warmer temperatures.
After purchasing the product, that is yam in the market. People still complain of not being able to preserve it for too long. A sure method to keep yam safe is the freezing method with this cheap Used Stainless Steel Three Door Commercial Freezer online store. With this method, you must always have a steady electricity/power supply at home. If power cuts off, even for a short while, the yam would start to defrost and ruin its texture.
How to preserve yam using the freezing method
Cut and slice the yam into pieces
Wash and pack your yam pieces into freezer bags.
Put in one bag only the exact number of pieces of yam that you want to cook at a time.
Once your pieces of yam are frozen, it can be hard to remove. So put a greaseproof paper on a flat tray then put the yams on it before putting it into the freezer.
When the yam is frozen, you can then remove the pieces and then transfer to a freezer bag. This way, the pieces will not stick together and you can select for use at your convenience.
When it is time to cook, do no thaw the yam. Cook from its frozen state. That is, from the freezer straight to boiling water.
Some people say they can freeze a whole yam. However, it would be difficult when you want to cook it as you cannot cut a whole yam that is frozen. You will have to leave it to thaw and thus, spoil the texture and outcome.
Ways in which farmers effectively store yam
· Leaving the yam tubers in the ridges after maturity
When the yam tubers are ripe for harvesting, some farmers leave the tubers in ridges so as to avoid any great loss. Then they harvest afterward. Through this method, the farmer can store the tubers for a period of one to four months. The advantage of this method is that there is almost no cost incurred. This is because the farmer does not have to build a yam barn.
Disadvantages of this method include:
It does not protect from pests.
The farmer cannot use the farmland because the yam tubers are in the ground.
One cannot properly check on the condition of the tubers while in the ridges.
During the dry season, the ground dries out and becomes harder, harvesting becomes almost impossible.
Storing the yam tubers in trench silos
Silos are agricultural storage facilities that can be made from materials such as wood.
A typical silo is the trench silo which is made in the field. A pit is dug and then lined with layers of straw. The tubers of yam are then arranged on the layers of straw either horizontally or vertically. This method does not allow for ventilation. The close contact between the tubers of yam also allows for decay to spread easily.
The use of yam barn
The yam barn is erected in the open air and under a shade. The yam barn consists of sticks to provide shade to the tied yams, bamboos where the yams are horizontally placed and ropes for binding the life sticks and bamboos together.