Loading ...
Sorry, an error occurred while loading the content.

Mashing, Steeping & DME

Expand Messages
  • Harry
    Stolen from Brew Your Own homebrew mag. It could be useful for some of you... Mashing or Steeping & DME: Mr. Wizard The wise one answers your homebrewing
    Message 1 of 1 , May 2, 2008
    • 0 Attachment
      Stolen from "Brew Your Own" homebrew mag. It could be useful for
      some of you...

      Mashing or Steeping & DME: Mr. Wizard

      The wise one answers your homebrewing questions.


      Dear Mr. Wizard,
      I'm a novice homebrewer, but I have spent a considerable amount of
      time reading Brew Your Own and various how-to-homebrew books. One
      thing that continues to confuse me is this: What exactly is the
      difference between mashing and steeping? Don't both procedures
      basically involve soaking grain in hot water?
      Sue Mullen Padula
      Barrington Hills, Illinois

      Mr. Wizard replies: Mashing and steeping are very similar processes
      at first glance. Both involve soaking crushed grains in hot water.
      However, if you look more closely, there are some sharp contrasts
      between the two methods.

      Mashing is a technique in which malted grains are soaked and amylase
      enzymes from the grains convert their starch to fermentable sugars.
      Some mashing methods combine malts that are very high in enzymes with
      starchy grains lacking enzymes. Other mashing methods only use malted
      grains. Mashing methods using adjuncts, such as rice or corn, work
      because enzymes from malt are able to move freely about in the mash
      once the malt has been crushed and wetted. The amylase enzymes cannot
      differentiate starch from malt or rice, and they go about their merry
      way breaking down (hydrolyzing) starch into fermentable sugars. The
      key to mashing is that the starch is broken down into fermentable
      sugars and special attention is given to controlling the mash
      environment — I'll get to that later.

      Grains that are mashed include any pale malt, lightly toasted or
      kilned special malts (such as Munich malt) and raw cereal grains.

      Steeping, on the other hand, is a method used to extract colors and
      flavors from certain types of specialty grains. Although the grains
      are soaked in hot water, the idea is not to have enzymes acting upon
      starch. Rather, steeping merely extracts compounds contained in the
      malt. The types of specialty malts ideal for steeping already have
      the starch converted to sugars during the malting process. These
      include the family of crystal or caramel malts — grain or malt that
      is roasted to such a high level that the starch molecules have been
      modified by heat to the point where malt enzymes don't do much to
      them. Roasted grains and malts include chocolate and black malt,
      roasted wheat, roasted wheat malt, roasted rye and roasted barley.
      Special malts such as Munich malts, pale wheat malt, pale rye malt
      and flaked cereal grains like barley, oats, corn and rice are not
      well-suited for steeping because these ingredients all contain a lot
      of starch.

      The key differences in the actual processes of steeping and mashing
      lie mainly in the thickness, temperature, duration and method used to
      separate the grain from the liquid. Mash thickness, or the ratio of
      malt to water, is important in mashing because enzymes are affected
      by the concentration of starch. If it's too high, the amylase enzymes
      lack the water needed to hydrolyze starch (hydrolysis is a term used
      to refer to breaking chemical bonds by the addition of water). If the
      mash is too thin, the enzymes are less heat-stable and are more
      susceptible to denaturation (enzyme destruction). Most mashes use
      between one and two quarts of water per pound of malt (~2 to 4
      liters/kg). When it comes to steeping, thin is good and it is common
      to use ratios as high as six quarts per pound (~12 liters/kg). The
      thin steep not only improves the efficiency of steeping, it is also
      convenient since the steep water is usually used to dissolve malt
      extracts after the steeped grains are removed.

      When it comes to mashing, the most critical variable to control is
      temperature. Different enzymes have peak activities at different
      temperatures, and some enzymes denature at just a few degrees higher
      than their activity peak. Brewers have named the various mash
      temperature rests for enzymes or their substrates because of this
      critical connection. We have the acid or phosphatase rest, protein
      rest, beta-glucanase rest, beta-amylase or fermentability rest, the
      alpha-amylase or conversion rest and the mash-off step. Few brewers
      include all of these temperature rests in their mash profiles, but
      mash temperature is always associated with enzymatic activity. These
      terms are moot when it comes to steeping. This is not to say that
      temperature is not an important consideration when steeping. Most
      agree that grain-steeping temperatures should be kept below about 170
      °F (~77 °C) to avoid the extraction of astringent tannins from the
      malt husk.

      Enzymatic reactions take time and most mashes last at least 60
      minutes. Steeping does not require such a long time because the only
      thing happening is the dissolution of the malt solids. Fifteen
      minutes is more than enough time for steeping. The final step is
      separating the grains from the liquid. Most steepers use a nylon bag
      that is easily removed from the steep like a tea bag. Depending on
      the amount of grain steeped and the amount of water used, the bag is
      rinsed with hot water. Mashing requires the more involved method of
      separating the wort from the grains. This process is called
      lautering. Wort is separated from the solids in some sort of
      straining device — for example, a lauter tun — and is thoroughly
      rinsed with hot sparge water to extract as much wort as possible.
      This step is required in mashing because of the mash thickness. If
      the sparging were not used the specific gravity of the wort would be
      around 1.080, as compared to sparged gravities ranging from 1.040 and
      higher.

      In summary, these are the key difference between mashing and
      steeping. To the extract brewer who uses steeping for specialty
      malts, mashing probably sounds very involved compared to steeping.
      However, the method of mashing is really not much more involved than
      steeping. It's just that there is a lot more going on, and more
      variations on brewing to explore, when mashing is entered into the
      homebrewing equation!


      Dear Mr. Wizard,
      When creating a yeast starter for pitching, is it favorable to use
      the particular type of dried malt extract (DME) that's used in the
      recipe? Or is there a standard DME that you recommend as a generic
      starter that remains neutral to the recipe's flavor? For example,
      should you use wheat DME when making a wheat-based beer or can you
      use extra-light plain malt DME as a neutral base? Or should you use
      the DME in proportion to the recipe when it uses multiple kinds of
      DME?
      John T. Kirk
      Houghton, Michigan

      Mr. Wizard replies: This question asks for opinions rather than any
      real facts. I can do that! Strictly speaking, any wort with a gravity
      ranging from 1.040 to 1.052 works well in starters with respect to
      growing yeast. But this can raise some real flavor questions if the
      starter and the wort the yeast is going into are very different. I
      typically use my palest standard wort (a wheat beer wort) as the
      starter for my yeast. My experience tells me that the flavor of this
      wort is light enough that the flavors of the other beers I brew will
      dominate any flavor contributed from the starter.

      In general, some of things I would avoid in a starter wort are dark
      colors, malty flavors, high bitterness, late hop aroma and gravities
      higher than about 1.052. I personally would not get too worried about
      trying to make a special starter for every beer. This is my opinion
      and I know some brewers don't agree with this advice, but there is no
      absolute answer to this question. Another thing I like to do is to
      pressure-cook starters in some sort of container so that I have
      starter wort that I can conveniently use when I need it. Canning jars
      or laboratory media bottles work well for this.

      I like making things easy for myself when possible and I typically
      steal a bit of wort from a batch and put it into media bottles
      instead of making a special batch just for starters. After the wort
      is in the bottle, I pressure-cook it with the lids loose for 20
      minutes at 15 psi pressure. After 20 minutes, remove the pressure-
      cooker from the heat and allow the pressure to slowly fall. Once the
      pressure is down to 0 psi, remove the bottles or jars, tighten the
      lids and store at room temperature. This wort will remain preserved
      until needed.


      For more of the Wizard's wit and wisdom, pick up the latest issue of
      Brew Your Own magazine, now available at better homebrew shops and
      newsstand locations.

      ==================================

      Slainte!
      regards Harry
    Your message has been successfully submitted and would be delivered to recipients shortly.