Updated version with video published on THE ACTUAL REASON TO BRINE YOUR TURKEY: SCIENCE EXPLAINED.
For most of the American, holiday involves turkey roasting. And a lot of holiday turkey recipes recommend brining your turkey before roasting it.
And according to conventional wisdom and most recipes online, the process of bringing will make your turkey juicer!
I was suspicious about it a while ago when I first attempted to roast a turkey because while those recipe websites did their best try to explain the science behind brining your bird before roasting, most of them are not very convincing.
For example, an article published on Thespruceeats.com said:
“When you place meat in a brine that has more salt than meat, the liquid will flow through the cell walls into the meat, which adds moisture.”
Well…if you did pay attention to your middle school science class, you know the above quote is probably incorrect.
Osmosis in Cell Is Not The Reason Why Poultry-Brining Works
Just a reminder of the concept of tonicity:
Saltwater you use to brine your bird is typically considered hypertonic solution because it has a greater concentration of solutes than the liquid found inside the cells.
When a cell is immersed in a hypertonic solution, osmotic pressure tends to force water to flow out of the cell instead of force water into the cell. It’s completely the opposite of what the article described.
Seeing article like that make me doubt if bringing poultry actually help make it juicier or it’s doing the complete opposite of what I want.
You might say: Why do you care about it so much, just follow the recipe, there is nothing to lose.
Well, The thing is you do have something to lose.because excessive sodium is very bad for your health. So as a person who cares about my kidney, if you want me to put extra salt in my food, I need a reason to justify it.
So then I did some research to see if there is any published research about brining poultry. here’s what I found:
(Notes that most of those researches are conducted with chicken, but I believe the results can be generalized to most of the poultries.)
Brining Actually Make Your Poultry Juicier And More Tender According to Studies
First: Bringing your bird actually does make the meat juicier!
A research conducted by researchers at the University of Florida published in 1978 on Poultry Science applied three different treatments to broiler meat, water chilled, brine-chilled, and no chilled. After cooking, the meat samples were evaluated for flavor, tenderness, and juiciness by a taste panel.
The result? All of them were scored favorably for flavor, tenderness, and juiciness, brine-chilled samples received higher scores than the other two.
Also, according to them, the brine-chilled meat had significantly higher moisture content and lower shear force values (Which is a fancy way to say it’s more tender) than meat from conventionally-chilled or no-chilled meat.
Another research published in 1979 on the same journal also found that Salt brined chicken lost significantly less water during the first 24 hr post-treatment when compared with water-chilled chicken.
Since all of those researches are done on chickens, I also did a simple experiment on turkey the other day and I can confirm it’s a real thing that brine turkey does taste significantly more tender and is juicier. So, well, the extra sodium of brining is justified for the sake of taste.
The Actually Reason Why Poultry-Brining Works According to Researches
A research published on Food Research International in 2005 conducted by a researcher at the University of Kentucky applied brining treatment on chicken and pork and found that brining produced a expansion of the myofibrils(which are is a basic rod-like units of a muscle cell), resulting in substantial swelling of muscle fibers, and enhanced water uptake and immobilization. 
So it’s not because of osmosis in the cell, it’s because, for some reason, the rod-like units inside a muscle cell expanded in the process of brining.
Brining Might Work Better On Breast Compared To Drumsticks
Finally: Brining seems to work better on chicken breast compared to drumsticks.
A research published on Journal of the Science of Food and Agriculture in 2000 conducted by researchers at the University of Kentucky and Kentucky State University found that in some case after brining treatment chicken Pectoralis major( which I believe is a fancy way to say chicken breast) seem has more structural change and is more extractable then chicken Gastrocnemius ( Which I believe it means drumsticks). 
The researchers then implied that this may explain the different water‐imbibing abilities of white and red meat when processed with salt.
Which is great, cuz in my opinion white meat definitely needs more tendering up treatment then red meat. So, how do you think? Do you brine your chicken before cook it? What is the optimal concentration of brine when it comes to brining in your opinion?
- Janky, D. M., Arafa, A. S., Oblinger, J. L., Koburger, J. A., & Fletcher, D. L. (1978). Sensory, physical, and microbiological comparison of brine-chilled, water-chilled, and hot-packaged (no chill) broilers. Poultry Science, 57(2), 417–421.
- Carpenter, M. D., Janky, D. M., Arafa, A. S., Oblinger, J. L., & Koburger, J. A. (1979). The effect of salt brine chilling on driploss of ice-packed broiler carcasses. Poultry science, 58(2), 369–371.Chicago.
- Xiong, Y. L. (2005). Role of myofibrillar proteins in water-binding in brine-enhanced meats. Food Research International, 38(3), 281–287.
- Xiong, Y. L., Lou, X., Harmon, R. J., Wang, C., & Moody, W. G. (2000). Salt‐and pyrophosphate‐induced structural changes in myofibrils from chicken red and white muscles. Journal of the Science of Food and Agriculture, 80(8), 1176–1182.