Mısır ve mısır ürünlerinde Aflatoksin ile Okratoksin-A`nın detoksifikasyonları üzerine araştırmalar

Abstract

7. SUMMARY Mycotoxins are known as toxic metabolites of toxigenic moulds and posess healt hazards, particularly aflatoxins are the most po tent carcinogenic substances known causing liver cancer in ani mals. Ochratoxin A has nephrotoxic property. Corn, one of the major agricultural product in Turkey, i s con sidered -.to be a risky crop for aflatoxins and ochratoxin produc tion. The best and most economical principle for prevention of my cotoxins is to avoid its occurance at the begining.But mycotoxin contamination is sometimes unavoidable and techniques for detoxi fication ( inaoti vation or removel) of mycotoxins are being alter native.. Many approaches have been investigated for detoxification of contaminated agricultural products. In this study, some selected detoxification procedures were applied to corn containing afla toxins and ochratoxin A and their effectiveness were determined. During storage of the corn at different conditions, %97 RH, 29°C was found to be optimum and %76 RH,15°C was found to be safe for mycotoxins formation. To know to what extent mycotoxins persist during home techno logies, some trials were carried out. During the making of bread from corn flour, up to 31-39 % aflatoxins were destroyed. Where as ochratoxin was stable (1-8 % reduced). The effect was enhanced by increasing times of baking and by increasing temperature. When corn kernels contaminated with toxins were boiled by atmospheric and pressure cooking with or without salt, 42-79 % of the afla- 125toxins and 45-46 % of the ochratoxin contents : were reduced. Pressure cooking was found to be more effective to aflatoxins and destruction of ochratoxin was high after atmospheric boiling. During autoclaving of the corn for 15 min. at 121 °C, 39.5-48 % of aflatoxins and 42 % ochratoxin were inactivated. The making of pop corn was realized with/without salt and oil additives.The average decomposition were found to be 41-51 % for aflatoxins and 53-71 % for ochratoxin. Addition of oil was reduced the effect of prosess. The possibility of destroying myco toxins by UV and sunlight is a subject of frequent speculation and according to our results no apparent chance found after irradiation. Detoxification trials using the combination of calcium hyd roxide: formalin mixtures and ammonia in the form of aqua and gas resulted in considerable reduction in toxins. Treatment of the corn with calcium hydroxide was reduced 95-97 % of the aflatoxin content. After ammoniation of the corn up to 97-100 % of aflatox ins and 96 % of ochratoxin content were reduced. As the result »aflatoxins and ochratoxin were moderately stab le during home technologies, these operations do not eliminate my- cotoxin risk in the foods. The techniques applied to feed-grade corn, particularly ammoniation seems to be. most promising techni que. Arnmoniaton, known to be practical and economic for large sca le operations resulted in corn with only moderate damaged prote in quality. 126

7. SUMMARY Mycotoxins are known as toxic metabolites of toxigenic moulds and posess healt hazards, particularly aflatoxins are the most po tent carcinogenic substances known causing liver cancer in ani mals. Ochratoxin A has nephrotoxic property. Corn, one of the major agricultural product in Turkey, i s con sidered -.to be a risky crop for aflatoxins and ochratoxin produc tion. The best and most economical principle for prevention of my cotoxins is to avoid its occurance at the begining.But mycotoxin contamination is sometimes unavoidable and techniques for detoxi fication ( inaoti vation or removel) of mycotoxins are being alter native.. Many approaches have been investigated for detoxification of contaminated agricultural products. In this study, some selected detoxification procedures were applied to corn containing afla toxins and ochratoxin A and their effectiveness were determined. During storage of the corn at different conditions, %97 RH, 29°C was found to be optimum and %76 RH,15°C was found to be safe for mycotoxins formation. To know to what extent mycotoxins persist during home techno logies, some trials were carried out. During the making of bread from corn flour, up to 31-39 % aflatoxins were destroyed. Where as ochratoxin was stable (1-8 % reduced). The effect was enhanced by increasing times of baking and by increasing temperature. When corn kernels contaminated with toxins were boiled by atmospheric and pressure cooking with or without salt, 42-79 % of the afla- 125toxins and 45-46 % of the ochratoxin contents : were reduced. Pressure cooking was found to be more effective to aflatoxins and destruction of ochratoxin was high after atmospheric boiling. During autoclaving of the corn for 15 min. at 121 °C, 39.5-48 % of aflatoxins and 42 % ochratoxin were inactivated. The making of pop corn was realized with/without salt and oil additives.The average decomposition were found to be 41-51 % for aflatoxins and 53-71 % for ochratoxin. Addition of oil was reduced the effect of prosess. The possibility of destroying myco toxins by UV and sunlight is a subject of frequent speculation and according to our results no apparent chance found after irradiation. Detoxification trials using the combination of calcium hyd roxide: formalin mixtures and ammonia in the form of aqua and gas resulted in considerable reduction in toxins. Treatment of the corn with calcium hydroxide was reduced 95-97 % of the aflatoxin content. After ammoniation of the corn up to 97-100 % of aflatox ins and 96 % of ochratoxin content were reduced. As the result »aflatoxins and ochratoxin were moderately stab le during home technologies, these operations do not eliminate my- cotoxin risk in the foods. The techniques applied to feed-grade corn, particularly ammoniation seems to be. most promising techni que. Arnmoniaton, known to be practical and economic for large sca le operations resulted in corn with only moderate damaged prote in quality. 126