|HAGLER JR, WINSTON|
Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/16/1999
Publication Date: 1/15/2000
Citation: WHITAKER, T.B., GIESBRECHT, F.G., HAGLER JR, W.M. USE OF LOOSE SHELLED KERNELS TO ESTIMATE AFLATOXIN IN FARMERS' STOCK PEANUT LOTS. PEANUT SCIENCE. 2000. v. 26. p. 39-44.
Interpretive Summary: Aflatoxin is a naturally occurring carcinogenic and toxic compound found in many agricultural commodities. Maximum aflatoxin levels allowable in food products are established by the FDA. The peanut industry has an aflatoxin control program that detects and removes aflatoxin contaminated peanuts from the edible market. The peanut industry wants to improve the current aflatoxin control program by testing peanuts for aflatoxin at the first point of sale or when farmers bring their peanuts to the buying point. Because aflatoxin is more likely to be found in poor quality peanuts, the peanut industry is interested in developing an aflatoxin sampling program for farmer's peanuts by measuring aflatoxin only in one or more of the poor quality peanut components. A method was developed to estimate the aflatoxin in a farmer's lot by measuring aflatoxin only in loose shelled kernels taken from a farmer's lot. Using loose shelled kernel has the advantage of allowing large samples to be collected from the peanut lot so that more accurate estimates of aflatoxin can be made. Results will help regulatory agencies and the peanut industry design cost-effective sampling plans to accurately detect and remove aflatoxin contaminated peanuts from food channels and make the food supply safer for the consumer.
Technical Abstract: Loose shelled kernels (LSK) are a defined grade component of farmers' stock peanuts and represented, on the average, 33.3% of the total aflatoxin mass and 7.7% of the kernel mass among the 120 farmers' stock peanut lots studied. The functional relationship between aflatoxin in LSK taken from 2 kg test samples and the aflatoxin in farmers' stock peanut lots was determined to be linear with zero intercept and a slope of 0.297. The correlation between aflatoxin in LSK and aflatoxin in the lot was 0.844, which was considered to be high enough to suggest that LSK, when taken from large samples, can be used to estimate the aflatoxin concentration in a farmer's lot. Using only LSK allows for much larger samples to be used to estimate the lot concentration since LSK can be easily screened from a large sample. If LSK accounts for 7.7% of the lot kernel mass, a 50-kg sample will yield about 3.9 kg of LSK which can be easily prepared for aflatoxin analysis. Increasing sample size from 2 to 50 kg reduced the coefficient of variation associated with estimating the lot concentration of 100 ng/g from 114 to 23%, respectively. As an example, a farmers' stock aflatoxin sampling plan with dual tolerances (10 and 100 ng/g) that classified lots into three categories was evaluated for two sample sizes (2 and 50 kg). The effect of increasing sample size from 2 to 50 kg on the number of lots classified into each of the three categories was demonstrated when measuring aflatoxin only in LSK.