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I made a sauce for macaroni and cheese about 6 months ago and froze the excess sauce. It is basically a bechamel sauce with a fair amount of cheese melted in.
I realize that if I thaw and re-heat this sauce there may be taste or texture differences - the cheese may seize, etc. But I'm mostly concerned with whether this will be safe to eat.
Is it possible for the sauce to have spoiled? If so, will reheating make it safe to eat or not?