The tomato sauce needs to be steamed for 15-20 minutes. The specific steaming method is as follows:

Materials/Tools: tomatoes, clean glass bottles, steamer.

1. Wash tomatoes.

2. Boil the tomatoes in boiling water for about 10 minutes to facilitate peeling.

3. After cooking, peel off the skin of tomatoes.

4. Crush the peeled tomatoes.

5. Put tomato juice into a glass bottle and fill it up.

6. After installing the tomatoes, be sure to tighten the cap tightly.

7. Put the packed tomatoes into the steamer and steam them for about 15-20 minutes. Note that there must be enough water in the steamer.

8. Store the prepared tomato sauce in a cool place. The shelf life is about 1 year.