Dead Chicken

[Shel_B]

What's the ideal amount of time between slaughtering a bird and cooking it? I have a vague recollection that a truly fresh-killed bird is not the best choice, and that one that's been dead a day or two gives superior results. Does it depend on how the bird is prepared? Or how the bird lived and was slaughtered? Maybe the timing has something to do with rigor mortis ...

Edited September 18, 2013 by Shel_B (log)

[liuzhou]

I think it's a personal / cultural choice. Most home and pro cooks here in China only buy live chickens, wring their necks, pluck, chop and cook immediately. To have them hanging around dead for a day or two would be anathema.

On the other hand there are those who prefer a gamier taste, although you aren't going to get much of that from most chickens today..

[Shel_B]

Speaking of dead chicken, I've known about Mike for decades, having read about him in an old issue of Life magazine when I was a kid. Perhaps you'll enjoy Mike's story ... sorry for the digression, but it's a cool story.

http://www.miketheheadlesschicken.org/history

[Martin Fisher]

There are many ways to do it.

Minimizing pre-dispatch stress and not cooling the carcass too quickly gives the best results.

Rapid cooling of the carcass leads to cold shortening which will toughen the bird.

~Martin

[Keith_W]

With any meat, you want to cook it either before, or after rigor mortis.

A quick physiology lesson - muscle contraction is caused by the release of intracellular calcium, which is kept in the sarcoplasmic reticulum by means of an energy consuming Calcium pump. When circulation stops, the Calcium gradient can no longer be maintained so it floods out and causes generalized muscle contraction. In addition, the actin and myosin molecules (the components of muscle fibre) fuse together to form an actomyosin complex - this is rigor mortis. A number of factors can affect how early and how long rigor stays for - for example, if the animal is stressed prior to death, its energy reserves are depleted, lactic acid builds up, and rigor mortis occurs earlier and more violently.

Over time, release of natural enzymes hydrolize the actomyosin complex, causing the muscle to relax. How soon this happens depends on a number of factors, including ambient temperature, size of animal, etc. Usually around 36 hours or so.

If you attempt to cook a chicken in rigor mortis, the muscles will be hard and will expel juices the moment you cut into it. There is therefore a window in which you should not cook a slaughtered bird. Either cook it early, prior to rigor, or late, after rigor has passed.

If you leave the bird for even longer, and provided the meat is not degraded by bacterial action or fermentation, the enzymes that break down muscle will continue to work. Breaking down a long chain protein into shorter chains produces new flavour molecules. Whether or not you find this flavour desirable depends on you. Traditionally, pheasants were hung for a few weeks to develop gamey flavour. Beef is dry aged for a few months to promote beefiness. I have never tasted an aged chicken, and I am not sure I would want to.

[Smithy]

Keith, that was an outstanding explanation. Thank you.

[scubadoo97]

With any meat, you want to cook it either before, or after rigor mortis.

A quick physiology lesson - muscle contraction is caused by the release of intracellular calcium, which is kept in the sarcoplasmic reticulum by means of an energy consuming Calcium pump. When circulation stops, the Calcium gradient can no longer be maintained so it floods out and causes generalized muscle contraction. In addition, the actin and myosin molecules (the components of muscle fibre) fuse together to form an actomyosin complex - this is rigor mortis. A number of factors can affect how early and how long rigor stays for - for example, if the animal is stressed prior to death, its energy reserves are depleted, lactic acid builds up, and rigor mortis occurs earlier and more violently.

Over time, release of natural enzymes hydrolize the actomyosin complex, causing the muscle to relax. How soon this happens depends on a number of factors, including ambient temperature, size of animal, etc. Usually around 36 hours or so.

If you attempt to cook a chicken in rigor mortis, the muscles will be hard and will expel juices the moment you cut into it. There is therefore a window in which you should not cook a slaughtered bird. Either cook it early, prior to rigor, or late, after rigor has passed.

If you leave the bird for even longer, and provided the meat is not degraded by bacterial action or fermentation, the enzymes that break down muscle will continue to work. Breaking down a long chain protein into shorter chains produces new flavour molecules. Whether or not you find this flavour desirable depends on you. Traditionally, pheasants were hung for a few weeks to develop gamey flavour. Beef is dry aged for a few months to promote beefiness. I have never tasted an aged chicken, and I am not sure I would want to.

Does that include fish?

[annabelle]

Yes.

[lesliec]

Haven't we moved on from hanging peasants?

Oh, pHeasants ... sorry, eyes are tired again.

[Smithy]

Haven't we moved on from hanging peasants?

Oh, pHeasants ... sorry, eyes are tired again.

[Keith_W]

Does that include fish?

As Annabelle said, the answer is yes. But for fish, the story is slightly different.

Land animals hang muscles off their bones against gravity. The muscles reinforced by, and tethered to the bone with strong connective tissue. Fish have their muscles and bones supported by the sea. They are neutrally buoyant (well most of them are), so they have comparatively little connective tissue. This is why fish is naturally tender.

Unfortunately, when fish go into rigor mortis, the weak tethering of muscle to bone, along with the generally poorer reinforcement of muscle, means that the muscle is more likely to tear itself off the bone or damage itself.

This is why Japanese practice ike-jime, or the rapid killing of fish. First the fish is spiked through the brain, then incisions are made behind the head and the tail. This severs the main artery, promoting rapid bleeding. It also exposes the spinal cord. A metal spike is passed down the spinal cord, destroying it. The fish is then bled out in an ice slurry and rapidly cooled. This delays the onset of rigor mortis.

The result, or so I am told, is fish with a superior texture. I have never done a back to back test of fish killed by ike-jime or fish that has been left to asphyxiate or dispatched by chopping the head off, so I don't know

[pastrygirl]

Does that include fish?

In the movie Jiro Dreams of Sushi, they talk about aging certain fish before it is ready to be served. I was so surprised, I thought sushi was all about extreme freshness.

[scubadoo97]

A fishmonger friend in California who is also an avid fisherman recommended fish achieve rigor mortis before being cut for better texture. At the table. I have heard this from multiple sources as well.

[huiray]

(I'm sure anti-fans of MY will find this to be ammunition for their viewpoint. :-) )