What is the difference between liquid and powdered pectin?
I found the following on the internet

Use only the type of pectin called for in your recipe. Powdered pectin and liquid pectin are not interchangeable in recipes. The preserving books seem to confirm that the reason liquid and powdered pectin may not be interchangeable is that the liquid version is always added after boiling but most types of powdered are added to the raw fruit or juice. 

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