Why is partial mash steeping done at 155 degrees F?

I am brewing a pumpkin ale today and I was wandering about the specialty grains used in this partial mash recipe.  I am using both chocolate and crystal malt in this recipe and it calls for me to steep at 155 degrees for 30 mins.  If neither of these malts have enzymes, than why might the recipe have me steep at a temperature which is normally used for sugar conversion by enzymes? Just curious and hoping to increase my homebrewing knowledge.  Thank you in advance for answers.

You want to water to be hot to made it easier to get the sugars out of the grains and into solution in the water.  But you don’t want it too hot (above 170) or you extract tannins into the wort.  So 150-170 is the generally given range.  145 would probably work just as well.

Water temps above 170 won’t necessarily extract tannins.  You also need a high pH for that.  Now, in steeping grains, it’s not uncommon to use a large volume of water, in which case the grain doesn’t have enough buffering power to lower the pH.  That’s why you should steep grains with about the same water/grain ration you’d use for mashing.  2 qt./lb. of grain is about as high as you’d want to go for steeping.

Thank you both for the quick responses.  ;D

A little late to this but in the absence of base malts is there even any conversion with choc & crystal malts? Why 155F? Surely 155F is a “safer” bet when converting but I’ve seen no problems when steeping specialty grains at 170-175.

After reading some in How to Brew, when steeping the grains would you also not be better served to add the grains at 155 and hold at that temp. Most of the kits say to add the grain at the beginning (ambient) and raise to 155 and hold. Also along this same line of thinking, would you not be better off to hold for one hour rather than 1/2 an hour?  This would be closer to a mashing procedure and should produce better results???

But you’re steeping, not mashing.  There’s no reason not to add the grains cold and bring up the temp, but there’s also no reason not to add them hot of you want to.  My experience is that 1/2 hr. plenty for extracting the flavor and color you’re trying to get, but if you want to go for an hour, no harm.

Thanks Denny

Is there a confusion of steeping specialty grains or mashing for a partial mash here?

I didn’t see any base malt listed to convert for a partial mash, without seeing the entire recipe I think this looks like an extract with grain recipe, which should be steeped and can be done at a higher temp. 165ish?

I do mostly partial-mash at this point, converting all-grain recipes to half-extract and mashing the rest in a 5-gallon cooler. It has been my assumption that it’s a partial mash when at least a significant minority of the recipe relies on base malts for conversion, but I observe partial-mash being used interchangeably with what is really extract brewing with steeping grains and maybe a bit of base malt for flavor. I don’t know if there’s a formal definition of partial mash, or if it even matters. Though from this thread I guess it does matter a bit in terms of being aware of sparging and temperature-control issues.

How about mini-mash? :smiley:

You’re making a good point. It shouldn’t be used interchangeably since they are two different techniques. My bad for not reading your OP better.

Is there a top limit to how hot the water can be for steeping? Below boiling?

Supposed to be 170F or just below AFAIK.

Not to be circular :slight_smile: but if tannin extraction is a moot point (see thread above) then 170 degrees wouldn’t seem to matter. But there must be an upper limit that affects flavor. Below boiling?

It really depends on if you’re just steeping or actually doing a partial mash, I’d think.  First, though, let me say that even if pH is a big factor in tannin extraction, I still think it’s possible that going too hot (whatever that is!) can be a problem.  But if you’re using diastatic grains (those containing enzymes) for a partial mash, going over 170 will denature the enzymes and you won’t get conversion.  That’s less important if you’re steeping non diastatic grains like crystal.  In that case, I’d take a “better safe than sorry” approach.  That said, back in the 80s, some homebrew authors had you leave the grains in for the whole boil.  In that case, like in a decoction, you probably won’t get any tannins of the pH remains under about 6.0.

That makes sense… thanks! I was thinking about non-conversion uses such as using crystal in a coffee extraction for adding post-boil… or even just steeping different types in small amounts to get familiar with their flavors.