can you cool wort with ice?

So I was thinking that as soon as the wort is cooled to 70 you add water to it anyway to get the 5 gal of beer, so why couldn't you freeze a gallon of the same water you are going to add to the wort anyway and drop it in to cool it down?

You can. I've done it many times when I did extract brews and they all turned out fine. However, you can only use it with extract. With all-grain, you don't want the extra water added to your final product.

I don't see why it wouldn't work, but be careful about the ice you use. Improperly cleaned or maintained ice machines can be a haven for bacteria growth. When I used to extract brew, I would but the gallon sized jugs of water in the fridge and that would usually be cold enough to drop the temp. I've also heard of people using dry ice to cool wort. Hope this helps.
Metalmosher:rockin:

Buy clean bagged ice from a store that goes through a lot of ice. Most of the better ice companies are big on sterilization and obviously the cold temps stave off infection for most of the life cycle. Go for ice that's clear, then you know that it's been filtered and doesn't have a lot of air in it.

The problem with freezing a gallon is that it can be too cold and too effective, leaving you with an iceberg that will take a day to melt. Cubes will melt quickly and cool effectively.

I used to sanitize cool whip or sour cream containers, fill with water and freeze with the lids on. I knew with confidence that it was sanitary. Of course, don't get too used to it because all grain will eventually lure you in.

yeah the bags of ice at the store have worked perfectly for me. the store up the street from me has 7 pound bags which 7 pounds equals one gallon of water

I brew with bottled water (due to taste issues out of the tap) and would just stick the top off bottles in the freezer so they would be on the verge of freezing when it was time to use them when I did partial boils. Worked great.

I actually registered to ask this exact question. What I have been doing for four batches now, with good luck so far...

I boil water in a sauce pan, 2 quarts at a time. Cover, cool to room temp, then decant to a new 1 gallon ziploc bag. Seal bag, freeze, repeat. Break into smaller pieces with a hammer before opening bag.

For my last two extract batches I did two boils of 1.5 gal each, so 3 gal of wort and 2 "gallons" of ice.

I was pouring my wort through a strainer to capture the hops and get some oxygen into the wort, straight off the boil, so wort around 200dF.

With 1.5gal of wort and 2 gal of ice in the primary the temp was 32dF at the end of the second boil. With 3 gal of wort on the ice, my 5 gallons of wort was at 65dF by the time I set the brew kettle down, took off my oven mitts and read the thermometer.

Ready to pitch.

Total my wort sat between 70 and 140dF for maybe one entire second.

So far so good. I shall relax and have a homebrew. If I have a trouble with it I'll bump this thread in the future.