The yeasts in fermented feed are good yeasts, different from moldy food. The smell is completely different. Mold also is fuzzy and can be white or black or light green. Yeasts are not visible.
There is a scum that can form on the surface, called "scoby", and it appears slightly white, but it's not fuzzy. That is what you stir back into the feed as it ferments. It's good.
Stirring the mixture a couple times a day keeps the molds from forming and allows the good yeasts to multiply. Google fermented feed and you'll learn lots of good information. I've been feeding my flock fermented feed for around ten years. Even new baby chicks get it.
There is a scum that can form on the surface, called "scoby", and it appears slightly white, but it's not fuzzy. That is what you stir back into the feed as it ferments. It's good.
Stirring the mixture a couple times a day keeps the molds from forming and allows the good yeasts to multiply. Google fermented feed and you'll learn lots of good information. I've been feeding my flock fermented feed for around ten years. Even new baby chicks get it.