Yesterday, had a homebrew buddy over, and we did similar batches with two different techniques simultaneously.
I did an enhanced double decoction, while my friend did an infusion/temp step mash.
Both batches used identical brewing water, adjusted for PH, and used a conversion rest at 152F. I relied mostly on 7lb of domestic 2row for diastatic power, while my friend used 7lb of Belgian abbey malt. My grain bill was 11.25 lb, while my friend had 14lb. The remainder of both grain bills were vitreous malts. Both mashes were rested until a negative reaction to an iodine test. Both used same sparge water. My friend used a false bottom in his lauter tun, while I lautered in my igloo mash tun without a false bottom.
Time start to finish was 6.5 hrs for step mash, while decoction took an even 7 hrs. Time included milling grain, mash, lauter, sparge, boil, and cooling. Cooling was accomplished with the same wort chiller using identical 15 gal kegs converted into brew kettles.
Observations between the two methods:
1) decoction method was more hands on, but not terribly so. Step mash required more frequent attention to thermometer.
2) decoction cleared faster during vorloft, and ran off at a higher rate while being much clearer (4 gals, I could still see near the bottom of pot!) I attribute this to the fact that decoctions will have a large percentage of the hot break stay in the mash tun. Much of the protein remains in the tun.
3) step mash required more sparge water (5gal vs 3.5gal).
4) decoction mash finished only 30 minutes after infusion. Conversion during the step mash was more steady, while decoction moved slow at first (within decoction) it converted quickly after the decoction was added back to the mash.
5) yield was higher with decoction- both were boiled down to s gravity of 1.060, but fermentable volume was 4.5 with step mash while 5.75 gals with decoction.
Both techniques had their advantages and disadvantages. Decoction method was more forgiving, but was more labor intensive. Step mash was less work but yielded less fermentables.
Hope this comparison was helpful to someone. I will be trying to repeat experiment in the near future to get a larger data set.
I did an enhanced double decoction, while my friend did an infusion/temp step mash.
Both batches used identical brewing water, adjusted for PH, and used a conversion rest at 152F. I relied mostly on 7lb of domestic 2row for diastatic power, while my friend used 7lb of Belgian abbey malt. My grain bill was 11.25 lb, while my friend had 14lb. The remainder of both grain bills were vitreous malts. Both mashes were rested until a negative reaction to an iodine test. Both used same sparge water. My friend used a false bottom in his lauter tun, while I lautered in my igloo mash tun without a false bottom.
Time start to finish was 6.5 hrs for step mash, while decoction took an even 7 hrs. Time included milling grain, mash, lauter, sparge, boil, and cooling. Cooling was accomplished with the same wort chiller using identical 15 gal kegs converted into brew kettles.
Observations between the two methods:
1) decoction method was more hands on, but not terribly so. Step mash required more frequent attention to thermometer.
2) decoction cleared faster during vorloft, and ran off at a higher rate while being much clearer (4 gals, I could still see near the bottom of pot!) I attribute this to the fact that decoctions will have a large percentage of the hot break stay in the mash tun. Much of the protein remains in the tun.
3) step mash required more sparge water (5gal vs 3.5gal).
4) decoction mash finished only 30 minutes after infusion. Conversion during the step mash was more steady, while decoction moved slow at first (within decoction) it converted quickly after the decoction was added back to the mash.
5) yield was higher with decoction- both were boiled down to s gravity of 1.060, but fermentable volume was 4.5 with step mash while 5.75 gals with decoction.
Both techniques had their advantages and disadvantages. Decoction method was more forgiving, but was more labor intensive. Step mash was less work but yielded less fermentables.
Hope this comparison was helpful to someone. I will be trying to repeat experiment in the near future to get a larger data set.
