Distribution of aflatoxins in product and by-products during glucose production from contaminated corn.
Aflatoxins are known to be hepatotoxic, carcinogenic, and teratogenic. A positive correlation has been established between the consumption of aflatoxin-contaminated foods and the increased incidence of liver cancer worldwide. A survey of Egyptian corn and corn-based products and by-products shows that the majority of the samples had higher limits of aflatoxin. We have conducted experiments to determine the fate and distribution of aflatoxin during wet-milling process fractions and investigate the aflatoxin destruction during starch conversion to glucose syrup. The present results showed that about half of the aflatoxin content (48.1%) in the infected corn grain was found to be lost in steep liquor, depending upon the aflatoxin type, arranged in the order G1 > G2 > B1 > B2. After wet-milling aflatoxins were distributed into starch, gluten, fiber, and germ. Gluten, fiber, and germ were the most highly contaminated fractions. The loss of aflatoxin during process of starches reached 54.4% in steep water and water process. Although the gluten fraction represents only 9.6% of corn, the higher percentage (25.3%) of aflatoxin was found in this fraction, the fiber and germ account for nearly 29% of the milled corn and contain 11.6% of the aflatoxin. On the other hand, 8.7% of the total aflatoxins in start corn was found in starch fraction which accounts 61% of the milled corn. Aflatoxins G1 and G2 were found lost in higher concentrations compared to the aflatoxin B1 and B2. A higher percentage of AfG1 (86.35%) and AfG2 (78.36%) and a lower percentage of AfB1 (16.3%) and AfB2 (14.7%) were found in starch fraction. The conversion percent of contaminated starch was 89.5% compared with control starch. It can be concluded that aflatoxins were destroyed during starch conversion. Consequently, glucose syrup produced from contaminated starch was found aflatoxin-free.
Aly
Soher E
SE
Mycotoxins Lab., National Research Center, Dokki, Cairo, Egypt. soheribrahim@hotmail.com
D016604:Aflatoxin B1 / Q000032:analysis; D000348:Aflatoxins / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D005506:Food Contamination / Q000032:analysis*; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006851:Hydrochloric Acid / Q000378:metabolism; D006868:Hydrolysis; D008113:Liver Neoplasms / Q000139:chemically induced; D013213:Starch / Q000378:metabolism; D003313:Zea mays / Q000737:chemistry* / Q000378:metabolism / Q000382:microbiology
D000348:Aflatoxins; C027955:aflatoxin G1; C029754:aflatoxin G2; C029753:aflatoxin B2; D013213:Starch; D016604:Aflatoxin B1; D005947:Glucose; D006851:Hydrochloric Acid