Grade Level: 6th Type: Food Science & Biochemistry
Students will discover the effect of heat on animal cells.
- What happens when an animal cell is exposed to extremely high heat?
- What happens during dehydration?
Many cooks and chefs, even some of the most renowned in the world, have mentioned that searing meats will help it keep its moisture throughout the cooking process. So the animal cells in these meats will supposedly keep more of its flavorful and natural juices if you sear it over a skillet prior to oven-baking. Yet it is also a fact that when animal cells are exposed to high heat, the protein in the cells will denature and become useless; thus disabling all functional activities within the cell and dehydrating. But which is true since they contradict each other?
Ingredients (found in supermarket/grocery store)
- Two raw, boneless steaks of similar weights and sizes
- Vegetable Oil
Equipment (found in most supermarkets/grocery stores and kitchen gadgetry stores)
- Two cooking/ meat thermometers with probes
- Two kitchen scales
- Cast iron skillet big enough to hold 1 of the steaks
- Pair of tongs
- Stove and oven
- Oven mitts and/or a potholder
- Preheat the oven to 350 degrees.
- Take your two similar cuts of steaks and take their “before” weight on two kitchen scales and jot it down. This is important.
- Coat the two steaks with just a tiny bit of oil so that it will take heat in faster.
- Have an adult help you with these next steps or supervise you: Set the cast iron skillet on the stove and turn up the heat to medium-high.
- Using tongs, place one of the steaks on the skillet and give both sides a very quick one-minute sear. You are not cooking the meat, just searing it on the surface.
- Remove from heat and place on a baking tray next to the raw, uncooked meat. Do not let them touch. Stick the probe of the thermometer in both of them.
- Slide the tray into the oven, close it up and set the stopwatch/timer and watch until the meat reaches 140ºF.
- Remove the meat that reaches 140ºF first from the oven, set it aside, and let it “rest.”
- Remove the second steak when it reaches 140ºF and note how much longer it takes for this take to reach 140ºF as opposed to the other steak. Let this “rest”, just as you did with the other steak.
- When both is done “resting”, weigh both on the scale post-cooking and record their present weights. Calculate percent-loss with this formula for both steaks: ((Pre-cooked weight - Cooked weight)/Pre-cooked weight) * 100 = weight loss percentage
- Record which one lost more weight/moisture. If they are similar percentages, it means it is insignificant. There we have our answer as to whether searing seals in moisture.
Meat #1 Sear
Meat #2 No Sear
Percent Loss (%)
Time Took to Reach 140ºF
Terms/Concepts: high heat/ temperature; moisture loss/ dehydration; animal cells; proteins
- McGee, Harold (2004). On Food and Cooking (Revised Edition), page 161, "The Searing Question."