As everyone else here already said, it really depends on the type of food and situation, but generally one isn’t better than the other.
I make a lot of smoothies and smoothie bowls and I always buy frozen berries instead of fresh. I can get them all year round for a fraction of the price and they get frozen at peak ripeness whereas fresh berries might not be fully ripe when buying them. And since they go into a smoothie, the texture changes from the ice crystals don’t matter. If anything, frozen is preferable over fresh to get that smoothie bowl texture.
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