Jump to content

delta H

  • Content Count

  • Joined

  • Last visited

  • Days Won


delta H last won the day on April 1 2016

delta H had the most liked content!

Community Reputation

1 Neutral

About delta H

  • Rank

Profile Information

  • Gender
  • Location
    Sacramento CA
  • Interests
    Brewing, Enzymes, Fermentation, Distilling, Design.
  1. delta H

    Glass lab still operation

    +1 on using electric rather than flame on a small setup. Even a cheap (cycling) electric hotplate is fine, as long as your boiling flask is in a sandbath (a larger flask with sand in it) which will even out the heating of the internal boiler a lot. You can also, in the short term, get around the lack of an integral thermometer in the still by using an infrared thermometer and aiming it at the top of the stillhead. If you do that use some black tape to aim at on the outside of the glass, and calibrate it with water first to make sure the boiling point is correct. (I'll note that Much of my experience is labwork unrelated to ethanol, but similar principles apply.) I would also recommend not running all the way to dry. If you run to 100C (which you should run directly into a graduated cylinder), then add water to the initial volume (or half of the initial volume, etc) you can very easily calculate the %EtOH. This also lets you pick the most accurate range of your hydrometer, if you'd like.
  2. delta H

    another rye question

    gamma amylase (γ-amylase) is also alpha-glucosidase (AG, or sometimes AMG or limit amylase). Basically it is an exoamylase that cleaves soluble a1-4 glucose polymers down to glucose (if you care, by attack at the non-reducing end of the oligo). Depending on the specific enzyme, sometimes you will also have 1-6 hydrolase activity (amylopectinase, useful on things like rice). In barley malt, the major exoamylase is beta-amylase which makes maltose (glucose-a14-glucose). Most recombinant/exogenous/microbial enzyme exoamylase products are AG.
  3. delta H

    maybe time to rethink copper stills

    I suppose I could take a line on the copper and Alzheimer's disease (ironically, I have published in PNAS and the paper was about copper biochemistry), but medical isn't my area of specialty and I've see enough of hypotheses about AD over the years to know to stay out of that mess. However, if one is going to worry about copper in a still, the issue to consider is the ethylcarbamate (urethane) level in the product. Ethyl carbamate is really quite carcinogenic, and is going to be present in rather high levels in certain distillates made from cane and types of fruit (http://www.ncbi.nlm....pubmed/11409971). There is certainly a strong argument for stainless heads/condensers/parrots/etc. in the final distillation. Copper catalyzes a lot of reactions, including the formation of ethyl carbamate... though ethly carbamate is effectively not volatile (in a beverage still setting), so doing a stripping run in copper (or having copper in reflux path of a rectifying run) would likely be a good thing (assuming the last condenser was not copper). Unrelated - I am very confused when I see talk on "non-GMO corn" or "gluten free" on a bottle of spirits. I suppose I could see being opposed to GMOs in general, but DNA doesn't go over a still any better than gluten does.
  4. delta H

    Deposit after emptying 190 tank

    +1 on the likelihood of carbonates from the dilution water - regardless of what the salts are (likely Ca++ and Mg++ carbonates in this case), as (less polar than water) ethanol concentration increases ions in solution will become less soluble, so things that were perfectly soluble in the initial water will precipitate as the solution becomes less polar. Probably you have high-mineral water, and if your cleaning water is close to saturation it won't be able to effectively dissolve the precipitate. Citric acid is a good suggestion of a cheap divalent cation chelator. Or use better water for dilution.
  5. delta H

    another rye question

    Some Malt Extract is actually just lautered malt mash that is boiled down. Alternatively, some mashes for these are malt+enzymes (which is still technically malt extract), and some are barley plus enzymes (which is usually called "brewers extract" or something without the word "malt"). Malt extract is an odd thing. If it is boiled down to concentrate there will be a lot of unfermentable sugars/oligosaccharides (good or bad in a beer, but bad in a spirit wash) an some loss of malt flavor (with possible gain of toasty flavor from the boil). If it is vacuum concentrated it should be more fermentable but might have significant flavor loss. Also, as an important note, yeast grown up on a diet of glucose don't do well in fermentation of a high-maltose mash. That means that if one uses a malt extract that had AG enzyme added (all malto-oligos to glucose) to grow up a yeast culture to pitch, then one must at AG to the wash. Conversely, if you want to use malt enzyme only mashing, then you need to grow that yeast up on a starter that didn't have AG in it (you need maltose around of the yeast won't express the transport/metabolism system for it - glucose is the "preferred" carbon source for yeast and most things). Basic point, if you make starter cultures (and you should, it is easy, just need a stirplate and a day), you should make the wash for the starter the same as what you are fermenting rather than risk issues with LME.
  6. delta H

    Water Chemistry

    Chlorine and chloramine can be easily removed (reacted away, technically) by adding sodium metabisulfite. This is standard practice among most homebrewers, and should be done for a couple reasons. Chlorine/amine can react with phenolic compounds in the malt (or other plant material you are mashing) and produce off flavors (ever have homebrew that tasted like band-aids?). The effect of low levels of clorine/amine on enzyme/yeast/stainless is less of an issue but is certainly isn't a good thing and removing it is going to help there too. Fe is more of a problem for the enzymes in the mash. The primary issue is loss of enzyme activity due to something called Fenton chemistry, which is basically Fe redoxing between Fe2+ and Fe3+ and kicking off reactive oxygen species (hydroxyl radicals, h2O2, etc). There are some easy ways to get rid of Iron but most will be issues for the calcium cofactors required by amylases (Ca2+ and Fe2+ bind the same sorts of chemical structures). I could go on at length about options, but the best is just to have (or make) water very low in Fe. If you can't manage that, there are some tricks relating to lowering the oxygen content of the mash (Preboiling the strike water just before use will lower the O2 drives reactive oxygen species formation), but in general higher iron means that you will need to mash longer and will be more likely to need to add exogenous enzymes to maximize starch conversion.
  7. delta H

    Make Offer! 300 Gal Stainless Mash Tank w/Mixer. New.

    Nice looking tank. Is that a steam jacket or just insulation?
  8. delta H

    California Distributor Recommendation

    Good luck, Rob. We are currently having loads of fun trying to find an appropriate building in CA for our stillhouse (fire regulations are a blast). This really isn't the easiest environment to run a business in, but few places care more about local so our hope is that it will be worth the struggle.
  9. delta H

    another rye question

    I personally have very little experience with rye - basically all of it has been adjunct brewing (for beer), and as less than 25% of the grain bill. I have only used malted rye in those cases. One would expect that malted rye has the correct enzymes (if not the correct level of them) to break down all of the polysaccharide in rye. Maybe the endoglucanases in the rye don't survive the malting process, or perhaps they are low Tm enzymes... Just out of curiosity has anyone mashed similar levels of malted and unmalted rye that has a comparison on viscosity (or lautering speed)? Hey SpecZyme - I've just left the enzyme (R&D) business recently, and we should definitely chat.
  10. delta H

    Adding enzymes to fruit mash

    I really depends on the type of fruit, the juice industry does use enzymes to increase extraction, so it will work if done correctly (not to say it will be worth the trouble). Pectinases might be worth looking into, maybe some other types of hemicellulases. What type of fruit is this in regards to?
  11. delta H

    another rye question

    I worked at two industrial enzyme producers for 6 years. Basically all (BG, etc) enzyme products are non-purified microbial enzyme broths. While some of them have have very high levels of specific enzymes (either by classic strain selection or genetic engineering), the strains will also express other enzymes. Two common host stains are A. niger and A. oryzae; both of those produce quite a bit of amylase. Try that unmalted rye mash without adding BG and there will be a very different result.