Effects of baking soda and fructose in reduction of ochratoxin A in rice and oat porridge during retorting process

Abstract

Ochratoxin A (OTA) is a possible human carcinogen found in a wide range of foods and agricultural commodities worldwide. This potent nephrotoxin is of concern because of its thermal stability under most conditions used during food processing and high incidence and concentration in oat-based baby foods. In this study, the effects of added baking soda (0.5% and 1%; w/w), fructose (0.5% and 5%; w/w), or combination of both (baking soda 0.5% + fructose 0.5%; w/w) on the stability of OTA during retorting of porridge type products made of oat flour or rice flour (10% solid content; w/v) were investigated using a laboratory scale horizontal steam retort. The reduction of OTA after retort was 17.2% in oat porridge and 53.8% in rice porridge, while addition of baking soda resulted in greater reduction of OTA. In retorted oat porridge, reduction of OTA was 30.3% and 47.9% with 0.5% and 1.0% of added baking soda, respectively. The reduction of OTA in retorted rice porridge reached 55.5% and 66.4% with 0.5% and 1% baking soda, respectively. Addition of fructose resulted in greater reduction of OTA in oat porridge (35.5–40.8%) but not in rice porridge. The reduction of OTA in retorted rice and oat porridges with combination 0.5% baking soda and 0.5% fructose were 35.8% and 39.8%, respectively. These results suggest that OTA may be reduced significantly by retorting of oat and rice porridge. In addition, added baking soda may contribute to the reduction of OTA in rice and oat porridges while added fructose may facilitate OTA reduction in oat porridge.