A survey was carried out of the micotoxicological and microscopic characteristics of rice comercialized in Pelotas and Rio Grande, RS, Brazil. Samples of whole [16], parboilized [16] and polished white rice [24] were collected in supermarkets, from may until september 2000.The occurrence of aflatoxin B1, B2, G1, G2, ochratoxin A, zearelenone, desoxynivalenol and T2 toxin was evaluated using thin layer chromatographic technique (TLC). The last two toxins were also evaluated by gas chromatography (CG). Mycoflora was determined using a surface Potato Dextrose Acid Agar, incubated for 5 days at 25ºC. The most frequent colonies were identified using the microcultive technique. The occurrence of microscopic dirt was realized in accordance with AOAC. Among the samples analyzed, 2 presented contamination by ochratoxin A (104 and 128mug.Kg-1) and three with zearalenone (559, 1117 and 1955mug.Kg-1), one of wich was cause by co-contamination with the first. One sample was contamined with desoxynivalenol (266 e 300mug.Kg-1), determined by TLC and GC. The results showed that 3.6% of the samples have levels above and 11% near 10(4)CFU/g. A brown rice sample was contaminated by microscopic dirt the above legal legislation (0.25%).
rice; micotoxin; mycoflora
