The tiny restaurant I work in (in small-town Thailand) has started purchasing homemade yogurt from a guy who delivers to several other shops.The flavor is good but it's quite lumpy. Maybe not a big deal to eat at home, but we are going to serve it to customers. (And no, it's a REALLY small restaurant, so we don't have the capacity to make our own rather than buying from him).
I have seen some info online that suggests lumps can be avoided by whisking more thoroughly earlier in the process, and that perhaps a higher heat might meld the lumps and whey together a bit more. But since he's been doing this a while, delivers to other places without issue, and I wouldn't want to offend him, I am not sure I can make these suggestions.
So what can be done once the yogurt is completed? I've read that putting it in a blender could make it more liquidy. We whisked it a bit with a fork (we don't actually have a whisk but if it makes a difference I guess we could get one) but perhaps we needed to make a longer, more concerted effort.
Or is there nothing that can be done after the yogurt is finished? Are the lumps are permanently in?