Market Prospects for Groundnut in West Africa COMMON FUND ...

psychophysics. Psychophysics directly concerns the correlation of sensory
experience with physical measures. Two measures of classification of sensory
tests are: i) affective and ii) analytical. Affective tests are used to evaluate
preference and/or acceptance of products. This method, however, cannot
provide a proportional relationship between sensory scores and physical
measures. Analytical tests are used for quantification of sensory
characteristics. Evaluating the textural quality of groundnuts, a sensory
panelist can either bite or chew those groundnut kernels. The physical
property differences between row, blanched and oil roasted groundnuts was
distinguished best by a compression test (Vivar and Brennan 1980). When
groundnuts are exposed to high relative humidity environment they absorb
moisture and become soggy, and consumers do not prefer such products.
Color: The color of raw groundnut kernels is attributed to both the testa and
the oil. Tannins and catechol-type compounds are responsible for imparting
the color to the testa. The color of cotyledons is due primarily to the oil color
present in the cells of the cotyledons. The measure carotenoid pigments
present in oil are β-carotene and lutein. Maximum concentration of these
pigments occurs in the immature kernels ie, 60 μg of β-carotene and 138 μg of
lutein per litre of oil and diminishes as the groundnut advances to maturity.
Consumer preference is for light colored groundnut oil. The characteristic
color of roasted groundnut is due primarily to the sugar-amino acid reactions
with subsequent production of melanins. Caramelization of sugars may
contribute to brown coloration of roasted groundnut. Consumers reject soft or
mushy roasted groundnuts even though they exhibit attractive color and good
flavor (Hodge 1953).
Indian groundnut is very popular in the international market for the table
purpose, due to its characteristic natural flavor, nutty taste and crunchy
texture and also has relatively longer shelf life. Therefore, with the growing
consumer taste the world over for organic food with natural flavor, Indian
groundnut has better export opportunity. Consumption of groundnuts as nuts
and in the manufacture of peanut butter is based on the use of roasted
groundnut kernels. Roasting time has a significant influence on the strength of
the odor and flavor. Raw and roasted groundnuts should be free of foreign
material, unadulterated with toxic or noxious substances such as pesticides
and microorganisms. The Food and Drug Administration (1969) issued
guidelines for food manufacturers who produce wholesome food items
including groundnuts and groundnut products. The “Official Methods of
AOAC” gives methods (36.020 to 36.024) for the determination of
adulterants in food.
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