If you are using frozen raspberries, allow them to thaw enough to separate from one another or defrost them in the microwave before heating to make puree. [2] X Research source
Cooking on too high a heat might cause the mixture to scorch. Sugar in particular has a very low burning point. Make sure there is another liquid in the pan to dissolve the sugar so that it doesn’t burn as it melts.
Raspberry puree will stay good in the refrigerator for a week or longer. You also have the option of freezing the puree until you need it.
Be careful not to blend to the point that the seeds become ground up and pass through the strainer. Blending results in a puree with a much smoother consistency, making it ideal for for use in sauces, smoothies, etc.
Chinois are most commonly used by chefs to strain purees.
Make raspberry puree far in advance or in bulk and freeze it to have it on hand for use in other recipes.
Simmering the puree as opposed to blending it can give you more control over the flavor, as the heat will cook out the natural tartness of the raspberries, and sweetness and tartness can then be modified using sugar and lemon juice. Always taste purees and sauces as they’re being prepared.
Confectioners sugar blends and dissolves better than regular granulated sugar because of how finely it is ground. [10] X Research source
Stir in the cornstarch a little at a time until the desired thickness is reached. Adding too much at once may cause the puree to congeal. [11] X Research source Keep in mind that the puree will thicken on its own somewhat as it cools.
Don’t use more liquid than the recipe calls for. If you’re cutting the lemon juice with water, make sure the proportions together still add up to roughly 1-2 teaspoons. It is not strictly necessary to use lemon juice in the recipe at all. The acid in the lemon brightens the tartness of the raspberries and also helps preserve the freshness of the fruit, but all that is needed is enough liquid to break down the raspberries as they cook or blend.
