Why sauces must be re-boiled after straining?

Sauces don't always need to be re-boiled after straining. It depends on the specific sauce and its intended use. Here's a breakdown:

Why re-boiling is sometimes necessary:

* Safety: Re-boiling after straining helps kill any harmful bacteria that might have been introduced during the straining process. This is especially important if the sauce was made with raw ingredients or if it wasn't cooked thoroughly.

* Consistency: Re-boiling can help to reduce the sauce's volume and thicken its consistency. This is because the heat causes the sauce to evaporate, concentrating the flavors and reducing the liquid.

* Flavor: Re-boiling allows the flavors to meld and develop more fully. The heat helps to extract and release flavors from the ingredients, creating a more balanced and complex sauce.

When re-boiling is NOT necessary:

* Already cooked and strained sauces: If the sauce has already been cooked thoroughly and was strained purely to remove solids (like a fruit sauce or a simple reduction), re-boiling might not be necessary.

* Cold sauces: If the sauce is intended to be served cold, re-boiling is unnecessary and can even affect its texture negatively.

In general:

* If in doubt, it's always safer to re-boil the sauce.

* The amount of time required for re-boiling depends on the sauce and its desired thickness.

* Always taste the sauce after re-boiling to adjust seasoning if needed.

Ultimately, the decision to re-boil a sauce after straining comes down to personal preference, safety, and the desired outcome.