Another reason for the dish soap however is that dust particles can scratch plastic, especially when rubbed in. So using some dish soap on the worst of your carboys will help encapsulate and lubricate the dust particles, reducing the risk of microscopic scratches which could harbor bacteria.
The vinegar works. I recommend that as well. But first use dish soap to do the heavy cleaning.
In Process: Mango Beer, Homebrewers Pale Ale
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