Effects of explosive puffing process on the reduction of ochratoxin A in rice and oats

Ochratoxin A (OTA) represents one of the most widespread mycotoxins in agricultural commodities in the world and is considered as a possible human carcinogen with its potent nephrotoxicity. Since OTA is stable under most food processing conditions, it has been detected in a variety of cereal grains and their processed products. We investigated the effect of explosive puffing process on the reduction of OTA in rice and oats. Moisture content of rice and oat grains were adjusted to 15% (wet weight basis, wb) and OTA was spiked at 100 μg/kg. Then the grains were processed by explosive puffing at 0.5, 0.7, and 0.9 MPa. The moisture content of puffed rice and oat snacks were in the ranges of 5-8% wb and 6-10% wb, respectively, and the moisture content in the puffed products were decreased with increasing pressure. In addition, decreased bulk density and increased degree of redness (a) were observed with increased explosive puffing pressure. The reduction of OTA concentration in puffed rice and oats were decreased with increasing explosive puffing pressures in the ranges of 15-28% and 38-52%, respectively. These results suggest that OTA in rice and oat may be reduced significantly by explosive puffing process, which can be applied to commercial production of cereal-based snack foods.