Pulsing the food processor works fine for one or two breast halves.

For grinding larger amounts, you can buy better quality grinders all of whose
parts are either plastic or high-quality stainless steel. With these, every
contaminated part can just be popped in the dishwasher. Just make sure they're
spaced apart so that the dry cycle can dry them quickly and completely.

I used to use the Kitchen Aid accessory, which worked fine -- but slowly -- for
smaller amounts; now I'm using a Maverick grinder ($99 from
pleasanthillgrain.com) which has plenty of power, takes standard blades and
plates, and whips through 12 pounds of chuck roast (for my weekly poker game
chili) in no time flat. Cleanup is quite easy, so I wouldn't hesitate to use it
for as little as a pound of meat, tear it down, and pop everything in the
dishwasher.

You can find standard size (#8, 10, and 12) high-quality stainless steel blades
and plates with 1/8, 1/4, 3/8 and 1/2 inch holes at sausagemaker.com.

-- Larry