Q: How can you tell if exotic oils go bad? I store oils such as safflower, sesame and peanut in a cool, dark place but I worry that they will turn.
A: There will be no doubt if specialty oils go bad because they'll give off a rancid smell that is very obvious. For prolonged shelf life it's best to store these oils in the refrigerator. If they become cloudy, the flavor will not be affected and they will become clear again at room temperature.
Q: Please tell me if there is any difference between saffron and Mexican saffron. I've heard the latter is about a quarter the price.
A: Saffron is a spice from the dried stigmas of the saffron crocus, while Mexican saffron comes from safflower, a plant originating in Asia and Africa but now also cultivated in other countries. It is the petals of this flower that are used as a saffron substitute. The safflower is considered to have a more bitter taste than the saffron crocus.
Q: What is the conversion for substituting all-purpose flour for cake flour? And also when I buy my flour presifted do I need to make adjustments to my recipe?
A: The conversion for substituting all-purpose flour for cake flour is three parts all-purpose flour to one part cornstarch. You now have made your own cake flour.
You do not need to make any changes to the recipe with presifted flour. If the package says "presifted," there is no need to sift. Just use a dry measuring cup for the amount called for and level it with a straight edge or, as many accomplished bakers recommend, weigh your ingredients with a scale for accuracy.
Note: Thanks are due to the clear-eyed readers who noted that last week I gave Jim Dodge credit for the wrong cookbook. He is the author of "Baking with Jim Dodge." Joe Ortiz is the author of "The Village Baker."
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