# Protein in cooked vs. raw chicken breast filet

I'm a bit confused by the label on an uncooked versus a cooked chicken breast. Both mention 23g of protein per 100 g of product:

If I cook the raw chicken myself, it loses a lot of water, so after cooking it only weighs 80% of what it used to weigh, and as none of the protein evaporated, my cooked chicken now contains 23g of protein per 80g, (28.75g / 100g) whereas the store-bought cooked chicken has 23g of protein per 100g

Where does this discrepancy come from?

• A quick Google search yields a variety of answers, but 20 to 22.8g per 100g of raw and 31g per 100g cooked are a couple of answers. I'm confident there are others on different sites. The problem with the correct answer for cooked is that there is no standard for what constitutes 'cooked'. How much moisture remains after it has been cooked? I cook it to an internal temp of 165F(74C) My spouse prefers it much dryer, I never measured its internal temp though Aug 23, 2018 at 11:17
• @Cynetta then, the data on the ready-cooked package must be wrong. Aug 23, 2018 at 11:46
• I think the confusion is in interpretation of the label. If you cook a 100 g piece of chicken with 23 g of protein, you will end up with a piece of chicken with 23 g of protein. It will now be less than 100 g due to moisture loss. As Cynetta points out, the amount of moisture lost will depend on how much it is cooked. It stands to reason that if you have 100 g after cooking, the protein content will be higher, but how much is based on the starting amount. Aug 23, 2018 at 12:05
• Just to be absolutely sure: You just boiled the chicken on high heat? Aug 24, 2018 at 10:52
• @Fabby more like stewed, so it would be frying but I added small portions of water-chili-vinegar marinade all the time to provide enough moisture Aug 24, 2018 at 11:37

Proteins are complex chemical forms so it depends. Let me elaborate by giving 2 extreme examples:

• If you boil an egg, the proteins unfold, hook into one another and therefore a liquid becomes a solid that doesn't melt again when you cool it down and there is no protein loss whatsoever.
• if you burn a piece of chicken breast fillet to a crisp on a barbecue overnight, a lot of protein mass will be lost.

In your particular case, I see the following possibilities:

1. there is an error in the label of one of the products and they probably did not send off their product for actual testing, but took their ingredient list from a database.
2. the cooked chicken is encased in a batter and the end product just happens to have the same protein content as the uncooked chicken.

You should contact a local consumer protection program and have them send off both products for actual testing as these kinds of tests are quite expensive.