Spaghetti sauce will separate if there is too much liquid and if the fat and water separates. Cooking the sauce slowly for a long time, adding liquid from the cooked pasta, and draining the liquid off the meat are all easy ways to stop the sauce from separating.
Bringing the fat and water together in your dish or ’emulsifying’ the ingredients will give you a smooth and thick sauce.
This article will explore the to reasons why spaghetti sauce separates and some easy ways to prevent and solve each one.
Why spaghetti sauce separates and how to fix it
Check out the top reasons why spaghetti sauce separates and what you can do to fix each one.
1. Too much liquid in the canned tomato
Adding too much liquid from canned tomatoes can cause your spaghetti sauce to become too liquid and it can seperate as it cooks.
I you are using whole canned tomatoes, drain off the extra liquid. You can also take the time to cook the tomatoes for longer which will evaporate the extra water.
Another option is to use jarred tomato puree instead. These are whole tomatoes that have already been purred which brings together the solids and liquid. Cook this slowly together with your meat and vegetables and you will have a thick and delicious spaghetti sauce.
2. Not cooking down the onions and carrot enough
The first step to creating a delicious home made spaghetti sauce is to cook down chopped carrot, onion and celery known in french as a ‘mirepoix’. These vegetables release a load of water and if it is not cooked down enough the water will stay in the sauce and cause it to separate.
Take the time to gently cook the vegetables until they have reduced in size by at least half. This will evaporate a lot of the water and help to stop the liquid and solid parts of the spaghetti sauce from separating.
3. Mixing in too much water
Adding loads of water to your spaghetti sauce can cause it to separate. Washing out the jars or cans of tomatoes with too much water will make your sauce thin and watery.
If you want to thicken the sauce, add 1-2 spoons of water from the cooked pasta. This will add starch which will help to emulsify and thicken the sauce.
4. Adding too much oil
Adding too much oil to your pan when cooking out the vegetables or meat can cause the spaghetti sauce to separate as it cooks down. Oil and water do not naturally mix so adding too much can cause an oil slick to form on the top of your sauce.
When cooking your vegetables, add 1 tablespoon of oil. You can add another teaspoon of oil when adding the meat if it needs it but don’t get carried away. Too much fat will cause the spaghetti sauce to become oil and water rather than a delicious mix.
For an easy spaghetti sauce recipe that does not separate, check out this video.
5. Cooking the sauce at too high heat
Cooking your spaghetti sauce at a temperature too high can cause the emulsion which is the mix between the fat and liquid of your sauce to break. This will make the sauce separate giving you a fat streak on the top and liquid base.
Avoid turning the sauce up above a medium heat. Take the time to cook the vegetables down until they are soft and reduced to half their volume. Gently brown the meat and slowly simmer the sauce until it thickens to your liking.
6. Not reducing the sauce enough
Not taking the time to reduce the sauce can stop the water and fat from coming together and emulsifying.
Take the time to simmer the sauce. Aim for at least 30 minutes but more time is better. It is tricky to overcook the sauce. You can even pop the sauce in a slow cooker and let it simmer on low all day. This will give you a thick and rich sauce.
7. Not draining the liquid off the meat
Using very fatty meat in your spaghetti sauce can cause the fat and water to separate. I like to use mince that is 80% protein and 20% fat. This allows a good amount of fat to make it taste delicious but not so much that it doesn’t mix through.
If you are using meat that is more than 20% fat, you can drain off the extra liquid and fat to help the sauce to thicken.
3 Ways to fix separated spaghetti sauce
Check out my top ways to fix separated spaghetti sauce.
1. Add pasta water and cook it down
Add a spoonful of pasta water to your sauce. Cook it slowly and let the sauce thicken. The start will help the fat and the liquid to stick together and to come together well.
2. Keep stirring
Another option is to slowly heat your sauce and stir it regularly. Use a wooden or heat resistant plastic spoon to bring the sauce together. Sometimes all it takes is a bit more heat and some gentle stirring to bring it together.
3. Add a dob of butter
Another easy way to help a separated sauce come together is to add some extra butter. Add 1 teaspoon of unsalted butter to your sauce and gently stir it through.
Once you have added the butter, turn the heat off. The butter will bring the sauce together and give it a rich flavor.
Reasons spaghetti sauce separates | Summary
Spaghetti sauce takes time to make from scratch. Cooking the vegetables and meat down to remove the extra moisture, slowly simmer the sauce and add some butter and pasta water to help the sauce come together.
I am an accredited practicing dietitian, experienced gardener and a dedicated cook. I love writing and sharing my experience so you can learn from my successes and mistakes.