A few more hours

We will be making our first cheese today, the starter needs a few more hours until it is ready. We should leave it until it smells "sharp and clean" but I don't know how that smell differs from slightly off milk. Sadly we have had to dump the fermentation barrel as even after being sterilised 4 times, it smells like 2 year old beer and I don't want yeasty tasting cheese. Photos will be up in a few hours of the first cheese, so check back then!