This step converts the remaining starches to sugars. Heat the grain (and malt or amalyse) to 62-63 °C for 45 min to 1 hour (stir occasionally), using 4.5L water per kg grain, then strain out the grains (use a kitchen sieve), keep the liquid (the wort/mash). Some methods involve bringing it to temperature, then holding it there for 2 hours in a big pot etc in the oven. When straining out the grains, rinse them several times with a small portion of the wort to fully wash them clean. Take care when heating the wort - it will easily boil over, quickly getting you banished from the kitchen. Watch it carefully, and enjoy the aroma.

When due to separate the grains from the liquid (lautering), raise the temperature to 75-77 °C. At this "mash-off" temperature the wort viscosity is favourable for quick & complete separation, enzymes are mainly inactive, and bacterial action is precluded.

It can be a differcult exercise to rinse the grains - getting them to soak through a collander or using a brewers "false bottomed" pail. John V writes ..
    Herewith a tip for those stuck with draining mash. The ideal item for this is the nylon paint straining bags sold at paint supplies stores. It comes in two sizes, the larger ones fits over an average-sized kitchenpan. I now use them for straining mash; my wife 'borrow' them for straining berry juice for jams and jellies. They clean very easily, just hold under running water.
To which Tony adds ...
    The nylon paint straining bags work well for me as well. I prefer using them over the top of large food grade plastic pails (available free at restaurants or deli's). The deep pail gives lots of capacity for strained liquid and leaving it drain overnight recovers prety much all of the available liquid from the fruit or mash. When the mash is too heavy the strainer elastic can't hold the weight, in this case use a stainless hose clamp (band clamp)to secure the strainer to the top of the pail. If you can't find a large enough clamp to fit around the bucket two smaller clamps can be easily assembled end to end and they are less expensive than one large one. I paid $1.70 Cdn. for a pair of small clamps a few days ago.

There are two enzymes which convert the starches to sugars & dextrins. Beta-amaylase "chops" the long starch molecules in half into shorter chains, whereas Alpha-amaylase "breaks off" the branches in the starch structure. Working together they do a great job, and convert 60-80% of the available starch to fermentable sugars.

Of the malted barleys, their enzyme potency is (in decreasing activity) 6 Row by a country mile, then 2 Row, Pilsner malts, Lager malts, Ale malts then Viennas and then Munichs.

    Starch Conversion / Saccharification Rest
    In this stage the diastatic enzymes start acting on the starches, breaking them up into sugars (hence the term saccharification). One group, the amylases, are enzymes that work on the more complex starches and sugars. The two main amylases are Alpha and Beta. Alpha works by breaking up long, branched starch chains at the branch points, leaving behind a variety of straight chain starches and dextrin-type sugars. The reduction of these large branched chains reduces the viscosity and "liquifies" the mash. Beta amylase works by separating these straight chains into fermentable maltose sugar units.
    Beta amylase works by hydrolyzing the straight chain bonds, but it can only work on "twig" ends of the chain, not the "root" end. It can only remove one (maltose) sugar unit at a time, so on amylose, it works sequentially. (A maltose unit is composed of two glucose units, by the way.) On an amylopectin, there are many ends available, and it can remove a lot of maltose very efficaciously (like a hedge trimmer). However, probably due to its size/structure, beta cannot get close to the branch joints. It will stop working about 3 glucoses away from a branch joint, leaving behind a "beta amylase limit dextrin."

    Alpha amylase also works by hydrolyzing the straight chain bonds, but it can attack them randomly, much as you can with a pair of clippers. Alpha amylase is instrumental in breaking up large amylopectins into smaller amylopectins and amyloses, creating more ends for beta amylase to work on. Alpha is able to get within one glucose unit of a amylopectin branch and it leaves behind an "alpha amylase limit dextrin."

Alpha-amylase works best between 65-67 °C, and dies within 2 hours at 67 °C.
Beta-amylase works best between 52-62 °C, deactivating within 40min at 65 °C.

(To understand how enzymes work, see Enzymes, a useful email from Stephen Alexander to the Homebrew Digest about enzymes, explaining how they affect the rate of a reaction, and how they work in the conversion of starch to glucose.)
You really need a mixture of the amalyses. Baker explains ...
    If you have a purified Alpha you're going to want to add a gluco with that, or you'll end up with a low DE syrup. Even if your amylase contains a Beta you won't get full conversion. Beta can't get past the branch points, and the mash will end up full of beta limit dextrins.

    An alpha beta combo will only give you a theoretical 42DE, if you add a pullulanase (a de-branching enzyme) it goes up to 50DE, and Alpha/gluco combo has a theoretical DE of 95.

    By the was DE stands for dextrose equivalent, it is a measure of the percentage of glucose bonds that have been hydrolyzed. Pure dextrose has a DE of 100.

    I'm pretty sure that Beano is a 1,4-alpha-D-glucan glucohydrolase (a type of gluco-amylase)

    One of the things to keep in mind when you are thinking about what enzymes you want to put in your mash is what enzymes are commercially available. There are probably thousands of starch degrading enzymes out there, but only a handfull are produced industrially.

    Let me back up a bit, there are two types of starch, amylose, and amylopectin. Amylose is a straight chain of glucose molecules, linked at the alpha 1,4. Amylopectin is a highly branched chain starch molecule, the straight part is linked at alpha 1,4 the branch points are alpha 1,6 linkages.

    Wheat starch is about 24% amylose and 76% amylopectin.

    Alpha amylase randomly breaks alpha 1,4 linkages

    Beta amylase starts at the non-reducing end and breaks off two glucose molecules at a time(maltose). Beta only breaks alpha 1,4 linkages and so can chomp right through an amylose molecule, but will get stuck at the branch point (1,6 link) on amylopectin leaving large "beta limit dextrins".

    Pullulanase is known as a "de-branching enzyme" it cleaves alpha 1,6 linkages leaving nothing but straight chains for the beta amylase to chew through. However you'll still be left with a wort full of maltose.

    A gluco-amylase, sometimes called amyloglucosidase, will break both alpha 1,4 linkages and alpha 1,6 linkages leaving glucose (dextrose) molecules in its wake.

    Since what you want to do is break down the starch and create dextrose as quickly and efficiently as possible my recommendation is to add alpha amylase and gluco-amylase together. I personally use a high heat stable alpha amylase to thin the mash and a gluco-amylase when the temp drops, I often add more gluco when I pitch my yeast just as a precaution. what the hell it can't hurt right?

    Is the Pullulanase enzyme also in the malted wheat? No, but you don't need it if you're adding a gluco-amylase
Zoran adds ...
    Termoamylase break down starch at high temperature, above 100deg C to short polysaccharide chains. The starch glue became liquid. These chains are attacked by glucoamylase not galactosidase,to give glucose as a final product. These 2 enzymes gave 95% yield glucose. The rest are not important for convesion, but can split to glucose with pullulanase, not pectinase. It is important to have appropriate pH check. Information,usage and prices for these enzymes you can find on net

The higher mash temperatures (65-70C) will produce dextrinous (heavy bodied beers, lots of "mouth feel") in a shorter period, whereas lower mash temperatures (62-63C) will produce more fermenatble (more alcoholic) beer over a longer time period. So go for 62-63C.

If you don't want to use malted grains, you can use amylase from a packet. Ted advises ...
    boil the unmalted grains then cool them down to 148 to 155 degree F (64 °C to 68 °C), then add the amylase and let it sit for 60 min. Test the liquid with iodine for starch conversion ( if there is starch present it will turn purple) Let it sit until it has converted. Don't seperate the wort from the grains untill after this process has finished.
You can use Iodine to test for starch - add a couple of drops to a spoonful of wort; if it turns blue starch is still present, and it needs more mashing. It has no reaction / colour change if there is no starch present. Iodine is poisonous, so toss away the sample you tested.

Jack warns ...
    few of the books on brewing/distilling say that weak sulfuric acid can be used to drop the Ph of grain mashes. According to the e-chapters you sent me, and the Seagram's distilling textbook I have:THE PRESENCE OF SULFURIC ACID DIRECTLY RESULTS IN THE FORMATION OF ETHYL CARBONATE IN THE FINAL SPIRIT!!!- THIS CHEMICAL IS A KNOWN CARCINOGEN AND IT'S PRESENCE IS RESTRICTED BY ALL GOVERNMENTS IN SPIRITS CONSUMED BY HUMANS!! I've always used lactic acid (or backset) for adjusting Ph in my beers ,etc.- I'm glad I've never used sulfuric acid.

The reaction taking place during mashing is one of hydrolysis and all the components of the grain particle are subject to varying degrees of changes. While the conversion of starch results mainly in fermentable sugars, the degradation products of the proteins and other components will ferment into fusel oils, aldehydes, esters and acids, which are grouped under the generic title of "cogeners". The composition and concentration of these cogeners determine the quality and characteristics of a whiskey. Thus corn, with its high starch content, provides the source of alcohol, while rye, with its high protein content, provides the "flavour". The variation of the respective proportions of corn and rye leads to different mash bills which exhibit different levels of flavour. The malt, with its unique function (to provide the amalyse to break down the starch), always occurs at a constant predetermined percentage, typically 10-12% of the grain bill.

Reese answers some common questions ...

    Q1) I have thought about using a different corn - but would the chopped or cracked corn not behave in the same way as flaked corn? Would it not absorb the water in the same way, after all it is still corn starch? It absorbs water, yes, but it only swells and remains relatively intact. Flaked corn, on the other hand, is corn that has been ground, rolled and then cut into flakes. When it absorbs water, it reverts back to its finely-ground state, hence your porridge problem. Chopped or cracked corn, while it absorbs water, will do so slowly, so you need to cook it longer and at a higher temperature. I kept my water at boiling through out the whole cooking process. Q2) Also, I take it that you suspend the boiled cracked corn inside a feed bag during fermentation? Yes. I have a large brewers bag that fits over the opening of my fermentation bucket, reaching to its bottom. After filling the fermentation bucket with sugar water, I line the bucket with the bag, cook the corn/malt and then simply pour it (and the excess water in which it was cooked) in. Then I tie the bag off with a loose overhand knot and put the lid on the bucket while it cools. It remains in the bucket and tied during the whole fermentation process. Afterwards, the bag will be emptied and washed for use in my next go. Q3) How do you get the wort off the fermented corn - squeezing with your hands? Some sort of press? A lauter vat/set-up? It should be possible to just simply rinse the bag with warm water, capturing what drains through. A good squeezing might help, but what you would get off wouldn't match the quantities of wort already suspended in the remainder of your now-brewer-bag-free fermentation bucket. The excess water that was available after cooking the corn/malt mix (and the corn's action on the wort while in the bucket) should have already contained enough starchy goodness to flavor the sugar-water wort base well enough.
Scott writes ...
    I'm no expert, but I do know from reading and personal experience that it's best to boil corn for 30 or 40 minutes to soften it up and gelatinize the starches (unless it's flaked corn, which has already been gelatinized). Make sure you use a stockpot that won't scorch the corn (e.g. thick stainless with a copper or aluminum bottom -- expensive! Or, like me, a non-stick aluminum pot -- less expensive). If you scorch the corn, your hooch will have a nasty stink (personal experience). If you don't free up the corn starches with a boil, your yield will be significantly lower. 1.040 is actually pretty good condsidering your mashing method, the amount of grain and the volume of water you used. You should be able to get closer to 1.060 if you add something like the enzyme gluco-amylase to the mash or wash.

    Why don't you get as much as with a sugar wash? Grain is about 50% starch, and you're never going to convert 100% of that to fermentable sugars. If you convert 75%, you're doing well.

    As for the iodine test still showing starch, there could be several reasons. Did you mix the malt throughout the mash (i.e. did all of the corn have a chance to get exposed to the enzymes)? Was your mash evenly heated throughout? Mixing/stirring to evenly distribute the heat is a good idea. You don't want hot spots destroying enzymes.
Should you ferment on the grain, or sparge the grains ? Ian Smiley suggests..
    If you're doing an all-grain mash of corn, rye, and or wheat, just ferment it all on the grain and strain it out later. It'll strain much more easily and efficiently after the fermentation. In fact, this is exactly what the commercial whiskey distilleries do.

    If you're making an all-barley-malt malt mash, you should sparge the grains out after mashing. Again, this is the way the commercial malt whiskey distilleries do it. However, keep in mind that malt mash does not undergo a kettle-boil the way an all-grain beer mash does, so you must limit the amount of sparge water you use or you'll over dilute the mash.
Brainsolenoid cautions ...
    I must admit humbley that I get a bit skiddish when I hear folks talk about fermenting on grains. There are a few items surrounding the mystery of fermenting / boiling grains, and in the Brewing community, these are some of the more basic items:

    1.) Grains were boiled in the late 1,700's up through modern times by Belgian Monks and German Brewers. They were performing what was referred to as a "decoction" mash, which was used to guarantee a cotrolled mash temperature in the times prior to thermometers. Part of the mash (and a little liquid) was pulled off the tun and sent to the kettle, where it was brought to boil, and then added back into the mash. This doesn't kill the enzymes as they survive in the liquid part of the mash. It makes a great Bock or other fuller bodied lager.

    2.) Brewer's boil their wort for numerous reasons, but mainly for reducing wort volume (and increasing sugar content), breaking proteins out of the wort for clearer beer, and for another extremely important reason......sterility. I get nervous when folks walk away with a snippit of info and fail with it. Yes, you can make a wash without boiling, but you are running some risks, sterilization wise, and will require an good size pitch of fast yeast to get things moving quickly. Even after boiling, I answer a lot of questions by Homebrewers who's wort has gone to mold even after boiling and pitching yeast. Long lag times produce off-flavors and and infections, and boiling helps at least to minimize what's carried over from the bacteria on the grains.

    3.) Now, I will preface this by saying I'm no chemist, but it is our belief that you have to boil for quite a while......say 90 minutes at least and it's still a function of wort get even close to the type of flavors found in extracts. Extracts, so we believe, gets that band-aid type background from overworked melanoidens. These produce the type of extreme maltiness you feel in Dopplebocks and higher gravity beers. Extracts are just worked to hard to get them in extract form and in contest tastings I can taste them right off.

    4.) Brewer's don't ferment on grains because it produces off-flavors as well as clarity nightmares. It's been written in brewing circles as well that fermenting on the pulp material produces methanol, though I have read to the contrary in (2) distillers resources that only pectins produce methanol. Since it is considered a "wood alcohol", we have always considered it as a byproduct of pulp fermentations. Though the "pectin" story seems to be spread throughout messages on this site (their source being the same (2) I've seen, no doubt), the Brewer / Engineer in me will stick with the logic that if fermenting on cellulose is a good thing, then we'ld all be cutting our trees down for hooch.

    It may be true that some Distillers are boiling their washes and are fermenting on grains, I'm sure you'll find some that aren't. The use almost laboratory standards that we don't have access to. Further, their pitching rates / oxygen contents are much higher than the amatuer distiller.
To which Ian Smiley replies:
    The information that BS gives is very accurate and completely consistent with the regimen I've learned and have been using for many years as an all-grain beer brewer, and achieving excellent results. I've done triple decoctions and cold lager fermentations to make continental pilsner, and I've done heavy English ales with dark specialty malts using other methods that BS mentions.

    I'm also aware that to ferment a beer on its grains would not only impart all kinds of off-flavours and undesirable bitterness from the husks, but it would engender yeast autolysis later in the fermentation cycle. And, for beer mashes, one definitely has to boil for about 90 minutes. This is not only important to achieve the hot break and to stabilize the flavour, but it's the only workable way to perform and control the hop extraction: bitterness, flavour, and aroma.

    Having said all that, I must point out that in my last contribution I was referring to whiskey mash, and not beer mash. There's a significant difference in the two processes. Whiskey mashes that are fermented on the grains are high-adjunct mashes (typically 80+% corn, rye, or other cereal grains) and mashed to optimize fermentability. The mashing temperatures of around 65C (149F) for 60 to 90 minutes are more than enough to sterilize (i.e. Pasteurize) the mash.

    Whiskey mashes are fermented from 60 to 84 hours, then they are strained and distilled. Given that the substrate is reasonably free of bacterial contamination (as it would be after 90 minutes at 65C) and that a copious and clean yeast starter is added, there's insufficient time for an infection to establish itself before the mash is brought to boil in the still. This is very different from a beer mash that has to undergo primary, secondary, and tertiary fermentation over numerous weeks, which would afford amply time for bacteria to thoroughly establish itself.

    Whiskey made from mostly cereal grains are not only fermented on their grains, but in some pot-still bourbon operations that use steam pipes to heat their still boilers, the grain is even placed in the still. Now, a flame fired still could never do this without burning the suspended grist on the bottom of the still pot.

    Malt-whiskey mashes are sparged the way beer mashes are, and are not fermented on the grains. But, they are usually not boiled, they go straight to the fermenter, are oxygenated, and are fermented for 60 to 84 hours, then distilled.

    I hope this helps to clarify my prior contribution re fermenting on grains and not boiling.
Raoul suggests that root ginger is a source of amalayse, decreasing fermentation times down from 15 to 3-4 days ...
    Try 1/8 tsp of fresh ginger root and 1/2 tablet of Beano with every gallon of whole corn and 8-10 pounds of sugar you use. I then dilute to 1.090sg (about 4 1/2 USGallons) and chuck in 1 oz of Fleischmanns ActiveDry, RapidRise or breadmachine yeast. After 3-4 days it is at 0.992sg and it has stayed above 95 degF. The ginger is a really cheap source of alpha-amylase and the Beano seems to act as a catalyst. No need to boil the wash either.

    A reliable source of a-amylase enzymes is ginger and I believe the inside white part of a banana skin. Also it is present in saliva but I don't like the idea of spitting into my wash. It replaces the function of 6-row barley or malting the corn. To prepare the ginger, add 1 cup of cold water (40deg F) and the ginger root into a blender and get it as fine as possible.

    You can also use the mash 2-3 times or so I have been told. Some old timers in the woods here report up to 5-6 times. This suggests that they do not have an efficient starch conversion but they didn't use ginger either.

    Use a paint strainer (or a stocking leg) as a bag to hold your grain. This solves the straining issue.

Stanford writes:
    I have produced a very favorable distillation by using Aspergillum oryzae during the fermentation process. One must first make a loose or watery, fully cooked porridge of grain mixture, cool to below 95 F, then sprinkle the inoculants over the porridge. No malting is needed! When the porridge has reduced to a more watery consistency, yeast without vitamins is added. Kept at blood temperature for a week or more will COMPLETELY exhaust the grain!

    The A. oryzae is much more effective in breaking down the starch to sugar than malt. This is how the Japanese make Sake from rice. I believe the results are superior, the AO produces more pleasurable aldehydes than malt, and retains more of the corn flavor.

    Additionally, as with sour mash, a little of the reserved ferment beer added to a new batch, alleviates the need for additional yeast or inoculants. Near continuous process! However, others have indicated that as batches progress, mutations can occur that will deviate from the original strains of both yeast and inoculants. Let your tongue be your guide!     This page last modified Tue, 20 Jan 2015 20:51:05 -0800