Quality of groundnut is largely determined by volume weight of pods, shelling percentage, 100 kennel weight, oil content, free fatty acid content, colour of pods and testa colour. Here are some of the factors that are affecting the quality of groundnut: 1. Volume Weight of Pods 2. Shelling Percentage 3. Hundred-Kennel Weight 4. Oil Content.
1. Volume Weight of Pods:
It is the weight per unit volume of pods, which indicates maturity and development of kernels when the pods arc disposed by volume. Varieties with small pods have higher volume weight than those with bigger pods.
Volume weight is influenced by rainfall distribution at pod development and availability of calcium and sulphur in pod zone. The average 100 pod weight varies from 73 g for TMV 2 (Spanish bunch) to 107 g for M 13 (Virginia runner).
2. Shelling Percentage:
It is the percentage of kernels to pods by weight. It depends on thickness of the shell, development of kernel and flowering pattern during the crop period. It is influenced by genotype, rainfall distribution and calcium in pod zone. Irrigated crop, generally, has lower shelling percentage than that from rainfed crop. Average shelling percentage ranges from 76 in the case of TMV 2 to 68 in M 13.
3. Hundred-Kennel Weight:
It is an indication of proper kernel development. In general, it is a varietal character with marginal influence of rainfall distribution and nutrient management. Average 100 kernel weight ranges from 30 g in TMV 2 to around 78 g in M 13.
4. Oil Content:
Oil content depends on temperature during first three weeks of pod development, maturity of kernels, which is influenced by rainfall during development stage and sulphur content in soil root zone. Usually, Virginia runners have higher oil content than Spanish bunch types. Oil content, generally, ranges from 48 to 51 per cent.
Light golden yellow colour of pods and testa of kennels is important when sold for edible purpose. Pod colour is influenced by nature of soil and soil moisture content at harvest.