THE EFFECTS OF DRYING AND SHELLING ON ASPERGILLUS FLAWS INFECTION AND AFLATOXIN PRODUCTION OF MAIZE*

The  effects of drying  and  shelling on  Aspergillus  fla\-us  infection  and  aflatoxin  production  of maize  stored under
laboratory conditions were investigated together with the intactness of grain and change of moisture content during the storage
period.
Fully matured maize var. Arjuna and CPI-2 were harvested at 90 and 97 days after planting, respectively, after which
they were unhusked and divided into 4 pans. The 1st and the 2nd parts were sun dried up to 20^ moisture content (m.c.) and
then shelled and re-dried up to 17 and 14% m.c.. respectively. The 3rd part was sun dried up to 17% m.c. and then shelled but
not re-dned. The 4th pan was sun dried up to 17% m.c. and then shelled and re-dried up to 14% m.c. The maize was sun dried
by spreading either the cobs or the kernels on the paved floor.
The nail-down wood and mechanical sheller were used for shelling the maize. After drying and shelling, maize samples
were stored in the jars which were covered with muslin cloth for 3 months under laboratory conditions.
A. flavus was isolated using dilution method on Aspergillus Flavus and Parasiticus Agar (AFPA). The damaged kernel
analysis was carried out at the beginning of storage to obtain the percentage of damaged kernel caused by shelling. The m.c.
and aflatoxin were determined using oven and High Performance Liquid Chromatography (HPLC) methods, respectively.
The m.c. decreased at 1 month of storage and then it was almost constant at 2 and 3 months of storage.
The percentage  of damaged kernels  of maize var. CPI-2 was  higher  than  those  of  var. Arjuna. The percentage  of
damaged kernels of maize shelled at 20% m.c. was higher than that shelled at 17% m.c. The percentage of damaged kernels
of maize shelled by mechanical sheller was higher than that shelled by nail-down wood.

*Paper presented at the Symposium on Pest Management for Stored Food and Feed, 5 -7 September 1995 Bogor, Indonesia.