The loss of water and volatile plasticizers.syfry said:What causes overcooked food to harden at the molecular level?
I don’t know about every food, but proteins (like egg whites) will unfold and start cross linking.syfry said:TL;DR Summary: What causes overcooked food to harden at the molecular level?
That, and why does the overcooked / hardened food become bonded or firmly stuck to the cookware?
This is true but there seems to be a bit pradoxical. Most seafood is best cooked with very short times and the same applies to offal but slow cooking at low temperature will render most meat very tender. Biology is a complicated business.Nik_2213 said:A casserole, covered with lid or foil to mitigate water-loss, generally improves given some extra time as the fibres and starch progressively break down to more digestible format.
Per VeratasiumCollagen, a connective tissue, helps hold the muscle fibers in meat together. When cooked in the presence of moisture, collagen dissolves into gelatin, which allows the meat fibers to separate more easily. This is the essence of tenderizing tough cuts of meat.
Interesting, so pectin probably makes a raw carrot hard, cooking softens the carrot, then burning the carrot will harden it again (but I'm still unclear as to how, molecularly).jim mcnamara said:This needs a dose of biochemistry (and basic chemistry) of pectin. Pectin holds plant cells together --middle lamella -- , so it is primarily responsible for the toughness level of unripened or uncooked fruit or stems or roots. See:
https://en.wikipedia.org/wiki/Pectin
Plant biochemistry texts often spends many pages on the synthesis and degradation (ripening or cooking mostly) of the many isomers. Water is required for controlled degradation.
Moist heat tenderizes meat:
Per Veratasium
Ok. So when all the moisture evaporates during cooking Meat proteins oxidize and turn black, other less damaged proteins make wonderful glue (example hide glue for animal hides). In general liquids derived from overcooked collagen, when dried, are hard to remove with water and detergent.
Plant cells have small amounts of proteins, which when degraded by high temp as a result of water loss, make "glue" mixed into the oxidized charcoal-like ash.
Burned fats make some really interesting toxins, like aldehydes, not glue necessarily....
Ah, the parts that had seemed like ruining of proteins were about how in meat, the proteins oxidize and turn black, while the other less damaged proteins make glue, and how heat degrades the plant proteins, but now after you've clarified how cooking is more like an early start to digestion, I'm seeing that ruined is probably the wrong wording for that.jim mcnamara said:Think of cooking as pre-digestion.
For our size, humans have relatively tiny teeth, and a small digestive tract.
Humans who cooked had a huge advantage over other primates in terms of killing food pathogens and parasites like tapeworms. Cooking kills of most bacteria, for example.
Mother's milk is an example. It contains the protein casein - a long AA chain. 212 AA's strung together.
Infants suckle. In less than five minutes all of the casein in the milk is broken down into short AA chains - polypeptides. In another few minutes most of the polypeptides are now single AA's. Anabolic (tissue building) processes "decide" to build new replacement tissues - skin collagens, muscle fibers, connective tissue. This anabolic switch gets turned on ONLY when the body senses a large enough dose of AA's:
a special group of branch chain AA's -isoleucine or leucine for example. These are in the list essential AA's
So the milk proteins are torn down to basic protein building blocks - AA's - then put back together into all-new proteins. If humans do not get those essential AA's over a period of time, the unused AA's can undergo gluconeogenesis - turning AA's into glucose. Or get flushed down the toilet in urine.
This is as close to 'ruined' proteins as I can get.
The amino acid - Lego analogy.syfry said:Had no idea the body is breaking all the proteins down into their individual components for reuse. That now makes more sense since parts are more useful in a wider range of places than their whole or completed bondings.
Let's hear it for the Crackling on a roast pork joint. Naughty but nice.Baluncore said:Damage to some blocks (overcooking) during the deconstruction, wastes resources,
Overcooking food usually hardens it because the heat breaks down the proteins in the food, causing them to become tightly packed together and lose moisture. This results in a tougher texture and less juiciness in the food.
Overcooking affects the texture of food by causing the proteins to denature and coagulate, leading to a loss of moisture and a firmer texture. This can result in a chewy or rubbery consistency in the food.
Overcooking can affect the nutritional value of food by breaking down vitamins and minerals, reducing their content in the food. Additionally, overcooking can lead to the formation of harmful compounds, such as acrylamide, which can have negative health effects.
Unfortunately, overcooking cannot be reversed to soften the food. Once the proteins in the food have been denatured and the moisture has been lost, the changes are irreversible. However, adding moisture or sauce to the food may help to improve the texture slightly.
To prevent overcooking food, it is important to monitor the cooking time and temperature closely, and to use cooking methods that are less likely to cause the food to become overcooked, such as steaming or braising. Using a meat thermometer can also help ensure that meat is cooked to the desired level of doneness without overcooking.