REDUCTION OF AFLATOXIN CONTAMINATION IN NUTMEG COATED WITH CLOVE OIL, PROPYLPARABEN, AND POTASSIUM SORBATE FORMULA

Abstract

Aflatoxin contamination caused by Aspergillus flavus in nutmeg has become a severe export obstacle. The study aimed to evaluate the effectiveness of coating formula to reduce A. flavus contamination in nutmeg seeds. Cleaned and dried nutmeg seeds were coated with a coating formula containing propylparaben, potassium sorbate, and clove oil, then challenged by spraying with A. flavus conidia suspension.  The treated seeds were incubated in humid plastic boxes. The colonization of A. flavus on the seeds was visually assessed after treatment. Aflatoxin contamination, the residue of propylparaben, and potassium sorbate were analyzed using High-Performance Liquid Chromatography (HPLC). The results showed that total aflatoxin in the shelled nutmeg seeds without coating was 471.69 µg kg-1, which is much higher than that in the coated seeds with formula (4.22 µg kg-1). Also, aflatoxin B1 was 462.10 µg kg-1 in the uncoated shelled seeds compared with that in the coated seeds (3.71 µg kg-1).  In the unshelled nutmeg seeds without coating, total aflatoxin and aflatoxin B1 contaminations were higher (376.06 µg kg-1 and 342.84 µg kg-1, respectively) than that in the coated seeds (3.00 µg kg-1 and 2.74 µg kg-1). Propylparaben residue in the coated nutmeg seeds was undetected, while, the potassium sorbate residue was detected as much as 30.86 mg kg-1 in shelled and coated nutmeg seeds.  The study showed that the coating formula was effective in reducing aflatoxin contamination in shelled and unshelled nutmeg seeds.