1. Prepare some fresh tomatoes. The surface of the prepared tomatoes must be complete, without bumps and scars. If there are any, don't use them, which will accelerate the deterioration.

2. Put a cross knife on the surface of each tomato and scald it with boiling water. Remember that it must be boiled water, not hot water, and it must reach 100 degrees. After boiling, the water actually has the function of sterilization and disinfection. Use it to scald off the skin. Then cut the tomatoes into pieces, and the knives and chopping boards we use when cutting must also be disinfected in advance to ensure cleanliness, hygiene, no water and no oil.

3. Then put it into a sterilized cooking machine and beat it into juice. After that, you can boil the ketchup in the pot. Remember that you can't use the iron pot. The ketchup made by many people can't be preserved for too long, which is caused by using the iron pot. The prepared pot must also be water-free and oil-free, plus tomato juice, and then add the right amount of rock sugar or white sugar. When the fire boils, it turns to medium heat. When cooking, you must keep stirring to avoid burning the pot.

4. When the tomato juice in the pot has become very sticky, add a small amount of salt and drop a few drops of lemon juice to improve the taste. Stir-fry until it is rustled and very sticky. After turning off the fire and letting it cool completely, put it in a water-free and oil-free bottle, tighten the lid and put it in the refrigerator. When eating, scoop a spoonful with a water-free and oil-free spoon, so it is completely no problem to eat for a month.

How to keep tomato sauce from mildew;

1, after the ketchup is opened, put it in the pot and steam it first, so that the ketchup can be preserved for a longer time even if it is not finished.

2. Put a layer of plastic wrap on the opening of the tomato sauce can, and then put it in the freezer.

3. Put some salt and sesame oil into the tomato sauce jar, which can inhibit the growth of bacteria in the tomato sauce.