Colour photographs for estimation of heterocyclic amine intake from fried pork chops of different RN genotypes indicate large variations

A questionnaire complemented with colour photographs was used to obtain information on dietary practices and preferences regarding home-prepared pork chops in a small (n=151) sample of Swedish consumers. The results from the questionnaire were combined with analytical results from meat of different RN genotypes, and showed that fried chops from a pig that was carrying the RN− allele (high glycogen content) had a darker crust and contained lower levels of mutagenic heterocyclic amines (HCAs) than chops from a non-carrier (low glycogen content). In this study population, the intake of fried pork chops only contributed slightly to the total HCA exposure; the total monthly intake of mutagenic HCAs was on average 256 ng, ranging from 0 to 1982 ng/month. However, using lower frying temperatures and meat from pigs carrying the RN− allele can further reduce the intake. From the photographs, most of the respondents chose fried chops from the non-carrier, which would result in an average contribution to the monthly HCA intake of 359 ± 402 ng (mean ± SD) compared to 35 ± 60 ng/month for consumers who preferred the RN−/rn+ chops. More than 20 times the amount of mutagenic HCAs was formed when frying chops of the non-carrier of the RN− allele at an initial pan temperature of 200 °C instead of 160 °C; 4.13 compared to 0.18 ng/g cooked meat.