How do I stop my gummy bears from getting mouldy?

Add potassium sorbate for the preservation

the mould you are seeing on the surface is the fungus "flower" made to release spores. The mycelium are buried into the gummy which you won't be washing off. I would toss them and call it a learning experience.

Try my Gummy Candy Recipe (about 50 gummies) 30g sheet gelatin, freshly ground 70g water (for blooming) 80g sugar (cook to 115-120 Celsius) 30g water (for sugar) 100g glucose (or other very thick inverted sugar syrup) 5g citric acid 2 drops food coloring (may vary) 15-20 drops aroma extract (may vary) The glucose plays a vital part to lifespan and texture of your gummies!

probably need to dry it longr. fungus grows into the gummy, so ... if youare okay with eating mildew, then go ahead of 'wash' it off the surface :P

Which recipe are you using? Mold is a sign of free water. If the water isn't bound, for example by rolling it in sugar and citric acid, the gummies can quickly become moldy. The ratio of water to gelatin has to be right. Let the gummies air dry before packaging them airtight, and make sure the surface of the gummies is dry. Don't eat mold! Washing it won't remove the mold, the mycel grows under the surface. Stay safe! 😋

Do you put a humidity meter and humidity pack when you jar them up? I use the Boveda humidity packs and they work like a charm. I'm also wondering if you burb your jars enough and shake them inbetween to break up the compactness inside of the jar.