How does one thicken their beer?

Oatmeal, flaked wheat or more crystal malt in the mash all contribute to a richer mouthfeel. I usually use 1 lb. of oatmeal in my stouts to make them smoother.

 

I added a pound of lactose to a chocolate brown. worked well.

 

it helps to use a yeast with low attenuation.

 

cara-pils, oatmeal, flaked wheat.

 

Mashing at a higher temp should also help here.

 

Unfermentable adjuncts are what you want. Things that raise the specific gravity but cannot be fermented by the yeast (digested and turned into alcohol + co2). That's why people point you in the direction of grains like crystal. They'll add "body" that will keep your final gravity higher and thus give you a thicker mouthfeel.

 

Not knocking the post but I wouldn't use crystal for the sake of getting mouth feel out of it as it will add sweetness to the beer unlike the other items listed. I have raised the temp as mentioned that will keep the sach from eating the long chain sugars but have read recently that oats, rye, and spalt (spelling) contain proteins that can be mashed at any temp while improving mouth feel. This is also important to any beer you might brew that is all Brett (it will even eat long chain sugars given enough time but not proteins). Good luck.

 

1st, Malto-dextrin as a powder or Cara-pils as a malt does the trick, which is a non-fermentable sugar that enhances the body and hence mouthfeel.

2nd, this is a real tip...try using melanodin malts, which is a German malt. Use this in a Pale ale, IPA, or anything Belgian.

According to Morebeer.com:

 

As said above crystal malts will give you sweetness but not much body. I use carapils, wheat or oats for a creamy thickness without altering the flavor of the beer very much. Just don't use too much-5-10% of the grain bill is plenty.
If you are an extract brewer you can steep the Carapils but the oats and wheat have to be mashed. I would go with the Malto-Dextrine.