Digital tip sensitive thermometers are as important to a chef as espresso is to m wife and I. While inspecting a fast food restaurant which serves predominantly burgers, I noticed the chef relying solely on color to determine doneness of burgers. As mentioned time and time again on barfblog, color is not a reliable tool to determine doneness of burgers due to premature browning of meat which may result before the burger reaches 160°F, the temperature required to inactivate pathogens such as E. coli 0157 H:7. Studies have demonstrated that burgers cooked to 135°C and allowed to sit for a few minutes looked the same as a burger cooked to 160°C. After explaining this concept to the chef, the response was well I cook the burger on high heat until it pretty much looks charred. Oh “that’s a deal breaker.” I have been dying to use this catch phrase from 30 Rock for sometime now. I went on to explain what happens when meat is cooked at high temperatures to a point of charring. A chemical change can occur in the meat resulting in the formation of heterocyclic amines (HCA’s). To prevent this from occurring, one can lower the temperature used for grilling and flip patties continually. The use of tongs or spatulas should be used to flip meat as a fork will puncture the meat causing juices to run causing flame ups which are responsible for polycyclic aromatic hydrocarbons, a carcinogenic compound2. It is interesting to note that marinades and spices may reduce the amount HCA’s found in the meat. The addition of spices such as rosemary, thyme, sage, and brine, reduced the content of HCA’s below 60% when compared to a control1. It is always a good idea to scrape off any parts of the meat that are charred. Finally, always use a digital tip sensitive thermometer to determine if your burger is done 71°C (160°F).

Sources:

1. Antioxidant spices reduce the formation of heterocyclic amines in fried meat
M. Murkovic, D. Steinberger and W. Pfannhauser
Volume 207, Number 6 / November, 1998

2. Environmental Health Services. Food Council News. Volume 4 Issue 3. May 2001. Capital Health