You and your food

Antioxidants

Antioxidants are added to muscle foods to protect lipids from undesirable reactions. Next time you buy ground poultry, check the ingredients statement, you may find rosemary extract. For years phytochemicals from rosemary have been extracted and applied to meat products to protect their color and flavour. Rosemary based ingredients were meant to replace synthetic antioxidants such as butylated hydroxytoluene or BHT. Without these compounds our favourite meat products would have painty odors/flavours and dull colours during prolonged storage. See the science HERE. 

Rancidity in Fish

Ever thought….why does my fish produce painty, oxidized odours so much more than beef or pork? Well, first lets talk about exsanguination. Exsanguination is the process of removing blood from an animal carcass during the harvesting process. Most of the blood gets removed but it is impossible to remove all the blood from the capillaries surrounding all muscle cells. Residual blood, means lots of hemoglobin. Now we can go back to our initial question, the leftover hemoglobin in fish is very very unstable compared to its mammalian counterparts. Importantly, fish hemoglobin has a greater ability to release its heme (the part that gives hemoglobin color), which then finds lipids and breaks them down producing the odor compounds we are oh so familiar with. See the science HERE.

Brown Meat

So…you left some ground beef in the fridge for one day too long, and it has gone from cherry red to brown. Assuming bacteria isnt an issue, this was caused by pigment (mostly myoglobin) oxidation. When muscle tissue is fresh, myoglobin is in its cherry red state (oxymyoglobin) but as you store the muscle tissues that same myoglobin undergoes oxidation (metmyoglobin) and turns brownish hue. Although we store our muscle foods at refrigeration, the low pH (~5.6 for beef) of muscle foods causes pigment oxidation to happen at a faster rate. This change in color will also impact lipids and cause oxidation. Another fun fact for your next dinner party – the purple-ish hue of vacuum packaged beef is caused by deoxymyoglobin. This form of myoglobin is produced when the the partial pressure of oxygen is low (i.e. vacuum packaged beef steak). See the science HERE.