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<snip> has anyone ever had a batch go bad? I have not read of anyone who has. If I syphon, should I take the lid off the primary, or try to do it through the vent hole? Is the risk really that great in a transfer?
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Never had a batch go bad. A friend that had a bad batch credits the experience for his attention to cleanliness 100 batches later.
Remove the fermenter lid when siphoning. Sanitize your siphoning hose. Be gentle and don't splash the beer.
Don't forget to taste your beer during racking.
Finally, to quote
Charlie Papazian : "Relax, don't worry, have a homebrew."