Hi everyone,
I'm not a homebrewer but found this discussion (and a few others that are similar) when looking for a bucket for food storage, and thought I'd chime in for future reference when people find this page via search.
I recently bought 50 lbs. of flour and need a way to store it. I decided that my preference, if affordable, was to buy new buckets as opposed to begging for them at local bakeries (what a pain, and who knows what those buckets have been through).
I have a Lowe's right down the street. It does appear, according to comments here, that these buckets change from time to time, so it is important to go and actually look at them. The ones I found are labeled with a "2" in the recycling triangle, and are also stamped "HDPE" underneath. It is also clearly labeled as being manufactured by Encore Plastics.
As previously mentioned, the Encore HDPE (high-density polyethylene) buckets are food-safe according to the manufacturer here:
http://www.e-encore.com/FAQpolyethylene.html.
One thing about the Lowe's buckets: the lids are an extremely tight fit. I could not get it off in the store, and neither could the first or second employee I talked to. Finally, a manager showed us that the best method is to place the bucket on the ground between your feet, and use both hands to pull up on one spot. Hopefully this won't be an issue, but since I'm storing food, it seems good that the lid is tight.
I am giving the buckets a good wash and will then fill them up. Best of luck to all you homebrewers--sounds like a hobby I'd like to try myself one day!