Talking Turkey

In the spirit of Thanksgiving, and since we've covered proteins for the past 3 weeks, I thought this was perfect timing for our seasonally favorite protein - turkey.

Both the domestic and wild turkey are the same bird, (not that you'd guess that by looking at them), Meleagris gallopavo. For this year (2007) 272,000,000 of them were raised for US consumption { http://www.nass.usda.gov/ }. Back in May those turkeys were just eggs in incubators. About 28 days later those eggs hatched into poults (baby turkeys) and the poults were moved to barns. For the next 4-6 months, yes - that is all the time most Thanksgiving turkeys spend on earth, they are fed corn and soybean meal supplemented with vitamins & minerals. Contrary to popular belief, turkeys are not fed hormones to get those big meaty breasts - that is done with breeding; federal regulations prohibit the use of hormones for poultry. Ranchers are allowed to give the birds antibiotics, but there must be no trace (residue) in the birds at the time of slaughter. The presence of antibiotics is part of the inspection process and if any is found, the turkey is considered adulterated and is rejected for consumption.

The most common designations of turkey available for purchasing are the following (per AMS 70-US Classes, Standards, & Grades for Poultry):

1. Fryer-Roaster - a young, immature turkey (usually younger than 16 weeks) of either sex (label won't say hen or tom) that is tender-meated with soft cartilage and smooth skin.

2. Young Turkey - a young turkey (usually younger than 8 months) of either sex that is tender-meated with less flexible cartilage and smooth skin.

Don't get one of these for Thanksgiving unless you are serving Turkey soup:

1. Yearling Turkey - a fully mature turkey (usually between 8 and 15 months) that is primarily used as breed stock.

2. Mature Turkey - an old hen or tom (usually older than 15 months).

For more information on this topic look here.

Most of what you find in the grocery store is the broad-breasted white (or bronze), which has a double breast so you get a lot more white meat. There are some producers raising heritage breeds - these are single breasted birds which are typically older (don't mature as quickly) and have a stronger flavor. Which to choose is a matter of personal preference, but whatever bird you do choose get a big one. There is roughly twice as much meat on a 15 pound bird as there is on a 10 pound one (assume 5 pounds of each is inedible bones, cartilage, etc.).

So now you have your bird, what's next? Brining. It is very popular, but why should you do it? Well, a brine is a salt solution, but many contain sugar & other flavorful seasonings. {Here is Alton Brown's recipe, but there are others. Typical brine solutions contain 1/2 cup kosher salt (or other non-iodized salt) per 1 gallon of water. If you choose to add sugar, add equal parts to the salt. Now if you remember the last post, or want to jump down now & review it, you'll know that there are salt soluble proteins in that turkey. And if you denature those proteins with the salt in the brine, they will increase their water holding capacity resulting in a juicier bird. Also in the last post you discovered the wonder of the Maillard reaction: sugar + protein = brown, yummy goodness. The sugar also helps balance the salty taste of the brine.

Now for the cooking. 165°F or 180°F? What if it is pink? If you use an old cookbook or follow Grandma's recipe you are probably familiar with the 180°F finished temperature. However, you are probably also familiar with overcooked, dry turkey. Pathogenic bacteria are dead meat (pardon the pun) after 140°F, and the meat of the turkey is perfectly fine for consumption at 165°F. Finished temperatures higher than this are a matter of preference (color & texture), not of safety. What about that pink tint? Well, you can't judge doneness by color, only by temperature. There are a few reasons why a fully cooked turkey may still be a little pink. Myoglobin is the oxygen-carrying pigment of muscle cells (what gives meat its pink/red hue). It can react with heated gases in the oven's atmosphere and maintain the muscle's pink hue even when cooked. Another possibility is nitrates (sometimes found naturally in water) can be converted to nitrites by the bacteria on the raw turkey which will cause the meat to retain a pink hue. If you have a good thermometer and it says 165°F in both the thigh and breast, you'll be fine. If you stuff your bird with dressing (and I don't recommend that you do), remember to check the temperature of that as well - it cooks the slowest and has absorbed all of the raw juices from the bird. It is cross-contamination of raw juices with cooked meat or shared utensils and undercooked dressing(stuffing) that cause the vast majority of food-borne illness at Thanksgiving.

And I can't forget about turkey causing sleepiness. Everyone has heard about tryptophan causing the post-meal nap crisis (heck, there was even an episode of Seinfeld based on this one). Tryptophan is one of the essential amino acids and it is a precursor to seretonin. However, you'd need an empty stomach and straight tryptophan to see any real results, and the levels in your turkey are too low to have any real effect. As a matter of fact, there is the same amount of tryptophan in an equal portion of chicken and more tryptophan in an equal portion of cheddar cheese, but no one complains of needing a nap after eating these. So why do you curl up on the couch after your Thanksgiving meal? You can blame it on all the carbohydrates and alcohol (i.e. sugars). They rev up your insulin and pull blood from your head to your gut to work on digesting all of that food. {more here}

I hope that you've all found this turkey talk informative and that you have a great Thanksgiving! Enjoy the meal, your family & friends and check back for my next post after I've slept off my dinner!