I am making blue cheese with your Roquefort culture. All seemed well until about 2 weeks or so after making the cheese, a definite ‘ammonia’ smell developed. I increased the air to the cheese and sprinkled with salt, this helped tremendously, however there is still a faint whiff of ammonia. Is it safe to eat?

Ammonia is a clue the blue mould is ripening the cheese and is quite normal. If very strong it suggests there is not enough ventilation, but this is difficult with single cheeses, too much ventilation and the cheese dries out too far. The cheese should not taste of ammonia, but suggest letting it come to room temperature uncovered before eating, to let the ammonical aroma dissipate.