Heterocyclic Amines of Cooked Meats and their Associated Cancer Risks in Pakistan

Abstract

HCAs are mutagenic and/or carcinogenic compounds detected at varying levels in the cooked meat products. Since their discovery, more than twenty, Heterocyclic Amines have been identified and quantified from high thermally cooked muscle foods. HCAs are divided in two major groups; thermic HCAs (< 100oC to > 300oC) or amino imidaz-azrenes and Pyrolytic HCAs or amino-carbolines. Muscle food originally contains three vital precursors of HCAs (IQ-compounds) i.e. amino acids, creatinine and hexoses. Dietary consumption of HCAs even at the ng/kg levels in the meat has become a vital causative factor for the development of mutagenicity and carcinogenicity in humans. Potential presence of HCAs in high temperature cooked food specifically in meats is a point of great concern for the health risk factor of Pakistani community. Pan-frying, grilling, deep frying, barbecuing, broiling etc. are common methods of cooking both at domestic as well as at restaurant levels in Pakistan. These all high thermal cooking procedures prevalent in Pakistan along with some other factors like cooking time, duration of cooking, high thermal cooking procedures, types of meat, types of cooking utensils used etc. are some of the common factors for the emergence of high concentrations of the carcinogenic/mutagenic HCAs in the foods. Research conducted on the commercially available RTE/RTC meat products from the Southeast Asian countries suggested an association between the production of potent carcinogenic heterocyclic amines and high thermal cooking of meats in country. Hence, the present study was intended to verify the presence and quantification of heterocyclic amines in differently processed chicken, mutton and beef cooked by high thermal procedures. ii During the course of this study simultaneous detection and quantification of HCAs in differently processed (microwave, pan-fried and deep-fried) ready-to-eat (RTE) chicken Kabab was determined. RTE kabab samples of four commercially available brands were analysed for simultaneous determination of HCAs using HPLCUV detector. Results revealed that highest total HCAs contents were produced by microwave cooking (0.7-35 µg/g) followed by deep-frying (1.6-22.3 µg/g) and panfrying (1.11-8.6 µg/g). Microwave cooking was found to produce highest level of IQ (nd-35µg/g) followed by deep-frying (nd-22.3µg/g) and pan-frying (0.2-7.5µg/g). Deep frying produced highest content of both PhIP and MeIQx up to 10 µg/g and 9 µg/g respectively. It can be easily speculated from these results that dietary consumption of 40g RTE chicken kabab /day indicated a relatively very high consumption of HCAs/day (up to 1.4 mg/d). To the best knowledge of the author, it is the highest known dietary consumption value of HCAs worldwide. Hence, our study presents a plausible affirmative association between the dietary consumption of HCAs and enhanced number of cancer cases. When control samples (unaided) of chicken, mutton and beef were barbecued it was found that total HCAs contents were quantified as 2707ng/g, 342.48ng/g, 575. 71ng/g respectively. Chicken was found to contain high level of PhIP contents (1987ng/g) followed by beef (526.37ng/g) and mutton (211.88ng/g). Marination of chicken, mutton and beef with turmeric (85.30%-96.97%), garlic paste (24.34%- 96.30%) and powdered red chili (36.21%-93.73%) reduced the total HCAs contents. Marination of chicken (24 h) with 2% (20g/100g) red chili (powder), 2 % kalonji, 2 % turmeric and 10% ginger paste completely inhibited the formation of PhIP. Marination of mutton for 24 h with 2% red chili (powder), 2% black pepper, 2% turmeric, 1 iii 0% ginger paste and 10% garlic paste prevented the formation of HCAs. Marination of beef (24 h) with 2% red chili (crushed), 2% red chili (powder), 2% black pepper, 2% kalonji, 2 % turmeric and 10% garlic paste reduced the formation of PhIP up to 93.32%, 100%, 100%, 87.78%, 93.78% and 68.52% respectively. These carcinogenic compounds have raised serious health concerns and made it pertinent to explore various ways to reduce, mitigate, inhibit or prevent the HCAs formation in cooked meats. Impact of various marinades, cooking duration and modes of cooking on the HCAs formation in meats at high temperatures was reviewed. The current study aimed to designate processing methodology with suitable marinade/s that may help in reducing or preventing the formation of HCAs. It was assessed through food frequency questionnaire that consumption of meat in general population and cancer patients was quite high. Cancer respondents showed high consumption tendency for chicken (81%) followed by mutton (70.56%) and beef (26.01%). Whereas findings indicated eight times high concentration of HCAs in chicken (2707 µg/g) than mutton (342.58 µg/g). Nearly half of respondents from general population indicated once a day consumption of meat (44%). Others responded for twice a day (10.4%) and thrice a day (5.40%) consumption of meat. At the same time it has also revealed the high trend of using restaurant based fast food (82.6%) and convenience based commercially available RTE/RTC meat products (58.4%) among Pakistan. The findings suffice to warn the public for HCAs presence in high thermal cooked meat products and their associated cancer risks in Pakistan and at the same time demand to shift from taste based selection of food toward health promoting feeding behaviors.