When your meat remains tough after pressure cooking, it's mainly due to undercooking the meat in the pressure cooker.
When you undercook the meat in the pressure cooker, it doesn't allow the collagen the meat to break down like it should.
Or you could also have overcooked the meat in the pressure cooker as overcooking the meat in the pressure cooker also causes the muscle fibers in the meat to be squeezed dry.
Some other common causes of meat remaining tough after pressure cooking are using too little liquid, choose a lean cut that s the connective tissue that is needed to break down into gelatin.
Tough cuts of meat like chuck roast and brisket also require enough time for the collagen to break down into gelatin, which is often 15 to 20 minutes of pressure cooking per lb or longer.
And if the meat is cooked too long in the pressure cooker, the collagen disappears and the muscle fibers also contribute to contract and turn the meat dry, stringy and tough.
And using the quick release method on the pressure cooker, instead of the natural release causes the meat fibers to seize up, and dehydrates the meat.
Also lean meats such as pork loin or chicken breast don't have enough connective tissue to benefit from long pressure cooking and will become tough, wheras fatty cuts of meat like chuck and shoulder become succulent.
And it's also important to use enough liquid, but not too much.
When pressure cooking meat, a minimum of 1 cup to 1.5 cups of liquid are required to produce enough steam to tenderize meat without burning or drying it out.
If the meat is undercooked you can add more broth or water and seal the pressure cooker and cook for another 5 to 10 minutes and if overcooked, you can often shred the meat and simmer it in sauce to add moisture back.
And always use the natural release and let the pressure come down on it's own for at least 15 minutes to 20 minutes after the timer goes up and use the trivet and place the meat on the rack to avoid boiling the meat in the pressure cooker, which can make the meat tough.
Meat does not need to be fully covered or submerged in liquid in a pressure cooker, although when pressure cooking meat the meat does require a minimum amount of water or broth, which is usually between 1/2 cup to 1.5 cups of water or broth to create the needed steam for pressurization.
The meat in the pressure cooker can rest on a trivet above the liquid or water in the pressure cooker and allow it to steam instead of boil.
When cooking meat in your pressure cooker, you should always add at least 1/2 cup to 1 cup of thin liquid like water, broth or even wine if you want, to prevent burning and burn errors.
Meat does not have to be submerged or covered in the water or liquid and instead the meat can be placed on a trivet or rack in the pressure cooker, which also ideal for avoiding a boiling texture.
And large cuts of meat such as chicken, release their own juices, although you should still add a base layer of liquid when pressure cooking these meats.
And to get better texture of your pressure cooked meat, you should use a natural pressure release, which is letting the pressure drop on it's own, instead of a quick release, especially if your meat is not fully submerged.
Foods that should not be pressure cooked are delicate foods which turn into mush like leafy greens and fish, dairy foods and dairy products like cream, milk, cheese which can curdle and foods that are prone to clogging valves or foaming like applesauce, pasta and oats.
And even thick sauces, fried foods, breaded meats and rapid cooking vegetables should not be pressure cooked due to the safety risks and or poor texture.
Dairy products like, cream, milk and yogurt and cheese should not be pressure cooked or cooked under pressure because they will curdle, separate or even burn.
Delicate seafood should also not be pressure cooked as the delicate seafood like shellfish, shrimp and fish are just too fragile for high pressure cooking and will turn into rubbery, mushy or stringy bits.
Fried foods are unsafe to cook in a pressure cooker because the high pressure and steam of the pressure cooker will cause the oil to splatter.
And any breaded meats that are cooked in a pressure cooker will become soggy instead of crispy and thick liquids or sauces like gravy, should not be pressure cooked as they can prevent proper steam generation and result in burning on the bottom.
Foaming foods like cranberries, oatmeal, applesauce, split peas and pearl barely can also foam up and block the pressure release valve on the pressure cooker which is dangerous as the steam cannot escape the pressure cooker like it should.
Pasta and noodles should not be pressure cooked as pasta and noodles will cook too fast and often result in a gummy and overcooked texture.
And quick cooking vegetables like leafy greens such as kale, spinach, broccoli, and asparagus should not be pressure cooked as they will become instantly overcooked and turn into mush.
Cooking food in a pressure cooker can lead to overcooking and a mushy texture, loss of nutrients, flavor limitation, safety hazards, inappropriate for frying and can be difficult with timing.
When cooking foods in a pressure cooker, it's impossible for you to add ingredients during the pressure cooking process, and the time that is required to pressure cook and for pressure to build and release can also be inconvenient for foods that you need quick cooking times for.
If the pressure cooker sealing gasket is old or the vent on the pressure cooker is blocked, it can lead to the pressure cooker malfunctioning and can lead to hot food splashing out, which can be dangerous.
Pressure cookers are also not good for frying foods in such as French Fries, chicken etc with oil as the high pressure and steam will cause the hot oil to splatter.
And because the pressure cooker pot is sealed, it does not allow for evaporation, which can result in blander flavors and prevent sauces from thickening up.
And although pressure cookers are efficient, the high temperatures of the pressure cookers can destroy heat sensitive nutrients like folate and Vitamin C, which can make the foods less nutritious.
And cooking delicate foods like leafy greens, soft vegetables and pasta in the pressure cooker can result in the delicate foods easily turning into mush.
And cooking foods like eggs in the pressure cookers can result in the eggs cracking and create a mess.
Pressure cookers are great for some foods, like soups, stews and tough cuts of meats as long as the pressure cooker is operated properly and safely.
But pressure cookers are not good for all kinds of foods.
Even many top chefs don't use pressure cookers for reasons which include.
They are just hard to control and adjust, as compared to techniques chefs like.
Chefs are very used to constantly tasting and making small adjustments.
The braising liquid doesn't reduce in a pressure cooker, so you need a lot of time after to a usable sauce out of it.