Pests and Disease

Pests and Disease

Groundnuts are attacked by; the Bean leaf roller (Lamprosema indicata), Leafminern (Stornopteryx subsecivella), Long-horned grasshopper (Phaneroptera furcifera), Cotton leafhopper (Empoasca biguttula), Slant-fac grasshopper (Atractomorpha psittacina), June beetles (Leucopholis irrorala), and Tiger moth caterpillar (Dasychira mendosa) amongst others.

Mould (Aspergillus flavous) can attack groundnut, leading to aflatoxin contamination, if the nuts are not dried sufficiently. Aflatoxin in peanuts is a serious problem. The peanuts can become infected either before or after harvest. Once they are infected, there is no way that the aflatoxin can be removed and the peanut becomes dangerous for consumption. If the peanut is free from the disease at harvest, correct drying can prevent later infection. Some aflatoxin infection can be visible to the eye as mould, but in other cases it cannot be seen. Laboratory tests need to be carried out to confirm the presence of aflatoxin. The recommended moisture level should be less than 10 percent.

Blanching is a process that destroys enzymes (biological compounds that are responsible for deterioration and off-flavours in foods after harvest), while retaining the colour and most of the nutritional value. It is a very simple process and basically involves the immersion of the foodstuff in boiling water or steam for a very short time, followed by rapid cooling by plunging in very cold water. To carry out this process at the small scale all that is required is a large tank in which water can be boiled. At a slightly higher level, there is specific blanching equipment available- both water and steam blanchers.