EFFECT OF TREATING WITH PROPIONIC-ACID, SODIUM BISULFITE AND SODIUM-HYDROXIDE ON THE BIOSYNTHESIS OF AFLATOXIN ON GROUNDNUT CAKE

Aflatoxin free groundnut cake (GNC) pretreated with 0.25, 0.50, 0.75 a nd 1.00% each of propionic acid, sodium bisulfite or sodium hydroxide al three moisture levels of 10, 15 and 20% was charged with Aspergillu s flavus (10(7)-10(8) spore) and kept in sealed polythene bags or in p etri dishes. The propionic acid and sodium bisulfite treated samples w ere kept for a period of 15 days at room temperature (which varied fro m 18 to 35 degrees C) in sealed polythene bags. In an another set sodi um bisulfite and sodium hydroxide treated samples were kept at 25 degr ees C for 25 days in petri dishes. The results showed that at 0.5% tre atment level of propionic acid or 1.0% sodium bisulfite at 10% moistur e, there was a complete inhibition of mold growth as well as aflatoxin biosynthesis when kept at room temperature. At 25 degrees C the aflat oxin biosynthesis was fully checked with 0.75% sodium hydroxide at 10% moisture and with 1.0% sodium bisulfite at 15% moisture, Out of the t hree chemicals tested as mold inhibitors, the propionic acid was found to be most effective followed by sodium bisulfite and sodium hydroxid e.