I have a stout I'm going to be bottling soon and unlike past recipes I've brewed which have called for corn sugar for priming, this calls for dry malt extract and lactose. Typically I've dissolved my corn sugar in a small amount of sterilized (boiled) water to easily introduce it and I'm wondering if there's anything special I should do in this case?

  • Isn't the point of boiling to sanitize the sugars you're introducing? Hopefully the water you're using is already pretty clean.
    – Room3
    Dec 6, 2010 at 21:43
  • I've never had any issues, but I certainly do not consider tap water to be sterile; "clean", perhaps. Dec 7, 2010 at 0:25
  • Most tap water is sanitized, especially city water. A lot of us even top up our fermentor with tap water, but my point is that the main reason for boiling in the priming stage is to sanitize the sugar you're adding in. Priming sugar isn't always nice and vacuum packed. It sits around in warehouses and on trucks with who knows what coming into contact with it. I'm simply recommending that you add the sugar in before you boil the water, not after
    – Room3
    Dec 7, 2010 at 18:42
  • Safe for drinking is not the same as sanitized. I don't think any city water is sanitized in the sense that we typically mean in brewing.
    – baka
    Dec 7, 2010 at 21:11
  • FWIW, I don't consider the sugar clean either, I was just emphasizing that I boil the tap water when integrating the sugar. Everything I've read in my (admittedly limited) brewing experiences has strongly advocated against using any unboiled tap water for brewing. Dec 8, 2010 at 13:09

2 Answers 2


If you follow the same procedures for the malt extract and lactose that you do for the priming sugar you will be good. The boiled water acts as a pasteurizer for the sugar and malt extract to eliminate any bacteria.


I would advise against using extract for priming. There is no advantage to doing so. In fact, it's more hassle. You have no idea of the fermentability of the DME, so you have no idea what level of carbonation you'll achieve. Sugar is fast, reliable, and tasteless.

  • Out of curiosity, why might a recipe call for the DME + lactose? I'm assuming it's contributing some character to the final beer and not merely serving as primer, or am I wrong in that assumption? Dec 8, 2010 at 13:12
  • 1
    My thought was that since the DME wouldn't get fully converted, it would leave some sweetness behind. And the lactose would give you a milky flavor. So the recipe is probably aiming for a sweet, milk stout.
    – Hopwise
    Dec 8, 2010 at 14:26
  • Indeed it is :) I think I'll use the DME + Lactose per the recipe to see what the results are. Dec 8, 2010 at 21:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.