A lot of big crystals in fudge makes it grainy. By letting the fudge cool without stirring, you avoid creating seed crystals. But instead of getting a few huge crystals (and grainy candy), you get lots and lots of tiny crystals, which make for thick, smooth candy.Click to see full answer. Also know, how do I fix grainy fudge?Grainy Fudge. The graininess is all in the length of time you stir the fudge after cooking it to a soft ball. Once it reaches a soft ball, I set the pot into a small pool of cool water and then start stirring until I can barely drag the spoon through it, or until it starts to turn grainy then I pour it up.Similarly, why is my candy grainy? If you have a lot of sugar crystals forming on the sides of the pan, your candy will be too grainy. Always stir gently to avoid splashing the candy mixture onto the sides of the pan. And, after the mixture comes to a boil, use a brush dipped in warm water to wash any crystals off the sides of the pan. Also question is, should fudge be grainy? Fudge is technically a crystalline sugar candy so a true fudge should have have the feel of tiny sugar crystals when you bite into it, but it should not be grainy. Most marshmallow fudges don’t really need careful attention to the cooling stage like fudges made without marshmallow.How do you make fudge smooth? Against the grain: secrets to smooth fudge Use corn syrup and butter Both interfere with sugar crystallization, so adding them to the fudge prevents the crystals from growing too large. Butter should be added only after the boiling is done.