Key Conditions for Optimum Fermentation › › Key Conditions for Optimum Fermentation As any wise man and Beatles fan will tell you, a good thing will happen if you let it be – may it be love, a tender rack of barbecued ribs or, in the case at hand, fermentation.
Enter yeasts, living microorganisms that readily grow in sugary solutions, produce enzymes (sucrose and zymase) that break up sugar or starch, and convert it into ethyl alcohol and carbon dioxide gas. ( Saccharomyces cerevisiae is the superstar species of yeasts, instrumental to baking, brewing, winemaking, and other such vital enterprises since ancient times.) The process of turning sugar into ethyl alcohol and carbon dioxide uses up almost 95% of the sugar, making these the chief products of fermentation.
The remaining 5% of sugar contributes to the simultaneous formation of several by-products: impurities such as glycerol, volatile acids, fusel oils, ethers, aldehydes, esters. These substances not only make for great band names, but also give character to ethyl alcohol with ever fascinating flavors and colors.
Temperature: high temperatures kill the yeast plants, low temperatures decreases their activity. The higher the temperature, the faster the rate of fermentation, but the lower the alcoholic yield. The optimum temperature is 78º F. Never exceed 90º F. Proportion: the optimum sugar to water ratio is 2 pounds to 1 gallon. Yeast and time: the usual proportion is 1 cup yeast to 5 gallons of water. At this ratio, in the right conditions, the yeast will produce enough ethyl alcohol to stop fermentation in 14 days. Yeast reproduces rapidly in sweet solutions, so less is better, but it will take a little longer for active fermentation to get going. Stand by your mash, and let experience guide you. Vinegar inhibition: when exposed to oxygen, the mash or wine will tend to promote the growth of another fungi that will manufacture vinegar. No oxygen, no vinegar. Settling time: when fermentation is complete, the mash or wine will be turbid and must settle. Settling will take several days or a week, even months in the case of wine. Chilling the fermented mash and/or filtering it will speed the process. Siphon or decant the clear solution and discard sediment. Try not to aerate the mash or wine unnecessarily, thereby risking the formation of vinegar.
After fermentation, the mash will be no more than 16% and usually not less than 3% ethyl alcohol by volume. It’s a dilute alcohol solution, so now’s the time to crank up your whiskey still and distill in high spirits. Posted by Jason Stone on April 20, 2015
- 1 What mash temp is too low?
- 2 Does mash temp affect pH?
- 3 What happens if mash pH is too high?
- 4 Is it OK to stir moonshine mash?
What temp should moonshine be cooked at?
The Foreshots – At each stage of the run, different alcohols are vaporized and make their way into the collection cup. The alcohol that makes fine, high-quality moonshine, is ethanol, which boils at a temperature of 175 degrees Fahrenheit. Other chemicals and types of alcohols, such as methanol, boil at lower temperatures and will be collected in your cup or jar after being condensed in the coil.
These chemicals are poisonous. Not only will they ruin the taste of your moonshine (or whatever alcohol you’re distilling), if they make their way into your final product, they can make people very ill. Generally, distillers make the first cut in the run when the temperature in the still’s pot reaches approximately 175-180 degrees Fahrenheit.
At this temperature, the ethanol in the wash will begin to vaporize, and you can be sure that the distillate collected before that point contains most of the methanol and other poisonous compounds. After making the first cut, throw away the contents of your first container.
What temp should mash be for distilling?
Warm the hot liquor to a strike temperature of roughly 68-70 degrees C (154-158F) to ensure a mash temperature of 63.5-64 degrees C (146-147F).
What temp should mash be to add yeast?
Rough Temperature Recommendations – The guide below will give you a rough idea of ideal water temperatures for proving your yeast.
Water at -4°F means your yeast will be unable to ferment. Water at 68° to 104°F means that your yeast’s ability to grow will be hindered, and its growth rate will be reduced. Water at 68° to 81°F are probably the most favorable range for the yeast to grow and multiply in. Water at 79°F are considered the optimum temperature for achieving yeast multiplication. Water at 81° to 100°F is the optimum temperature range for the fermentation process. Water at 95°F is the fermentation temperature that yields the best result. Water at 140°F or higher is the kill zone for yeast. At temps like this or higher, you will have no viable live yeast left.
Of course, these tentative estimations can be higher or lower depending on the type of yeast you are using, and whether it is active dry yeast, live yeast, or rapid rise yeast. The bottom line is that yeast thrives in warm water, sleep in cold water, and die in hot water.
What mash temp is too low?
Temp Too Low – By mashing low will give you more fermentable sugars, leaving the beer thin and dry. Leave the mash temp too low (below 140 °F) for too long, then you run the risk of ending up with a “watery” beer that does not taste good. If your mash temperature is too low, you have the ability to quickly raise it by adding boiled hot water to the mash tun.
Add the hot water in small amounts, and stir the kettle/mash tun after each addition. Add enough until your grain’s temperature is at the correct level. If you are using a Brew-in-a-Bag (BIAB) setup, you can directly heat the kettle with the grains still inside. This works with both propane burners and all-in-one systems.
Nylon bags have a melting point of 515 °F (268 ° C), so you should be more than safe heating directly in the kettle. I do usually hold up the bag slightly as I turn the burners on to prevent any chance at scorching.
What is the best pH for moonshine?
Ideal Mash pH Range – Before I jump into anything, it’s important to understand that mash pH is measured at room temperature, not the actual hot mash. The optimal mash pH of 5.2-5.6 is referring to the room temperature measurement. This was initially incorrectly published in a BYO article and caused a slew of backlash.
What happens if you mash in too hot?
Why your mash temp matters – The bad news is that it will likely affect the outcome of your beer. The good news is it’s probably not as bad as you think, and you can mitigate the effects by taking swift action. We’ll get to the swift action in just a moment.
First, know that the normal mashing temperature range is 145 – 158F (63 – 70C). In general, mashing at the higher end of that range produces longer sugars which are harder for the yeast to eat. More sugar will be left over after fermentation resulting in a more full-bodied beer. Mashing at the lower end of the range produces shorter sugars, which the yeast will gobble right up.
This leaves behind a thinner, drier beer. Mash too much lower than that and you’ll end up with poor starch conversion and a really thin, “watery” beer. You’ll also start breaking down precious proteins needed for head retention. On the other hand, if you mash too high (168-170F), you’ll run the risk of permanently killing the conversion process.
Does mash temp affect pH?
How does temperature and pH affect mashing and lautering? Brewers manage the temperature and pH values to control enzyme performance in the mash, reduce tannin extraction during lautering, and to enhance yeast performance during fermentation, as well as the overall product quality (Buttrick, 2012).
- During mashing, the enzyme activity depends mostly on the temperature, it increases with rising temperatures and each enzyme reaches its own optimum range (Kunze, 2014).
- Raising the mash temperature increases the rate of catalyst reactions, accelerates the rates of protein unfolding and precipitation, quickens diffusion and dissolution steps, aids in mixing and at certain temperatures causes starch gelatinization and breaks down the cellular structure of endosperm tissues in unmodified (Briggs, 2004).
If the mashing temperature is below the optimum range for proper conversion, it may reduce grain extract and increase lautering duration (Agu, 2011). Different mashing temperature steps are designed to maximize the hydrolysis of different grist compositions.
Proteases with an ideal range of 35-45°C break down the protein matrix holding the starch granules. Glucanases perform best at 45-55°C and break down hemicellulose gums, whereas amylases break down the starch granules and work best at 61-67°C (Buttrick, 2012). At higher temperatures enzyme inactivation occurs because of the unfolding of the three-dimensional structure of the enzyme called denaturation (Kunze, 2014),
Wort fermentability can be altered by mashing temperature because of the lower denaturation temperature of β-amylase; attenuation will not be apparent until post-fermentation (Muller, 1991). The structure of the enzyme can also change depending on the pH value. Figure 1. The reaction of Bicarbonate in an Acidic Solution to Increase Alkalinity (Briggs, 2004) The grist composition will be the largest influence of wort compounds produced with some considerations being malt to adjunct percentages, average protein content, and malt modification. Figure 2. The reaction of Calcium Ions when Phosphoric Acid is used to Increase Acidity (Briggs, 2004) Calcium phosphate is less soluble at higher temperatures causing mash pH to lower during decoction mashes and declines further during boiling. A source of error is from measuring the pH of wort or the mash is at ambient temperatures as weak acids separate more as the temperature increases so the pH of the solution falls.
At 65°C, the pH of the wort is approximately 0.35pH lower than ambient temperature and 0.45pH lower at 78°C. As the temperature of mash changes from the different rests and mashing steps, so will the pH (Briggs, 2004), Mashing a lightly kilned malt with distilled water results in a wort of about 5.8-6.0pH, this value is maintained by the natural buffering solutions from phosphates and proteins from the grist.
Single-stage infusion mashes are run at a compromise range of 5.2-5.4pH which results in 5.5-5.8pH at ambient temperatures. Reducing the pH too many results in greater soluble nitrogenous materials but extends the saccharification time and reduces extract yield.
- Lowering the pH with calcium and other means accelerates the rate of degradation of starch, increases total soluble nitrogen and free amino nitrates and reduces wort colour.
- Simultaneously, alterations of the solubility characteristics of proteins occur, the buffering power of the wort increases, and eventual hop utilizations decreases (Briggs, 2004),
A result of the increase of the free amino acids released is that they contribute as aromatic pre-cursors while minimizing the formation of ferulic and coumaric acids (Schwarz, 2012). Further lowering the pH using lactic acid from either chemical or biological sources has been shown to improve the quality and processing of beers when the grist consists of 20% (Lowe, 2005) and 50% unmalted barley (Lowe, 2004).
- Enzymes optimally within narrow pH ranges: peptidases are at 5-5.2pH; glucanases at 4.7-5pH; and β- and α-amylase are at 5.4-5.6pH and 5.6-5.8pH respectively (Buttrick, 2012).
- In mashing, the hydrolysis of a substrate relies on the mixture in the grist, water to grain ratio, grind coarseness and grist distribution of particle.
Similarly, the mash conditions and brewhouse operations can affect the optimum pH (Briggs, 2004), Unfortunately, the relationships between wort composition and the temperature are much better understood than that of wort composition and pH as there is limited research dedicated to the matter (Bamforth, 2001).
- However, the principal method of controlling the pH of the beer is during mashing; the extraction of buffering solutions of hydrolysing barley compounds will directly affect the final pH structure of the final beer (Taylor, 1990),
- During wort collection, buffers are rinsed from the mash which increases pH, particularly if there are bicarbonate ions present in the sparge liquor.
The higher pH draws unwanted polyphenols and flavours from the grain bed. Best practises are to maintain liquor pH are reducing bicarbonates and by using proper levels of calcium (Briggs, 2004), Additionally, maintaining the temperature of the grain bed during lautering is known to improve filtration by reducing the viscosity of the mash (Bühler, 1996) During the hot break in the kettle, the wort pH reduces by 0.2-0.3 mostly from the further precipitation of calcium-based salts.
This brings the wort near 5pH, which is ideal for vigorous fermentation for many yeast strains. Fermentation causes a drop of 0.5-07pH. At the end of fermentation, barley-based beers are approximately 4.1-4.5pH with wheat beers being slightly more acidic. Depending on the practices in the brewery cellar, beers such as lambics and other sour styles will have an even lower pH level from acid-producing bacteria (Buttrick, 2012).
References Agu, R. (2011) Effect of Mashing Temperature on the Processability of Malted Barley. Tech.Q. Master Brew. Assoc. Am.48(1), 4-8. Bamforth, C. (2001) pH in Brewing: An Overview. Tech.Q. Master Brew. Assoc. Am.38(1), 1-9. Briggs, D., Boulton, C., Brookes, P., and Stevens, R.
- 2004) Brewing Science and Practice.
- Woodhead Publishing Limited, Cambridge, UK, 104-122.
- Bühler, T., McKechnie, M., and Wakeman, R.
- 1996) Temperature Induced Particle Aggregation in Mashing and its Effect on Filtration Performance.
- Food and Bioproducts Processing, 74 (4), 207–211.
- Buttrick, P.
- 2012) Mashing, in The Oxford Companion To Beer; Oliver, G.
Ed.; Oxford University Press, New York, 576-578. Kunze, W., Manger, H., and Pratt, J. (2014) Technology Brewing & Malting, 5th ed; Handel, O. Ed.; VLB, Berlin, 220-225. Lowe, D.P., Ulmer, H.M., Barta, R.C., Goode, D.L., and Arendt, E.K. (2005) Biological Acidification of a Mash Containing 20% Barley Using Lactobacillus Amylovorus FST 1.1: Its Effects on Wort and Beer Quality.
- Journal of the American Society of Brewing Chemists.63 (3), 96–106.
- Lowe, D.P., Ulmer, H.M., Sinderen, D., and Arendt, E.K.
- 2004) Application of Biological Acidification to Improve the Quality and Processability of Wort Produced from 50% Raw Barley.
- Journal of the Institute of Brewing, 110 (2), 133–140.
Muller, R. (1991) T he Effects of Mashing Temperature and Mash Thickness on Wort Carbohydrate Composition.J. Inst. Brew.97, 85-92. Schwarz, K., Boitz, L., and Methner, F. (2012) Release of Phenolic Acids and Amino Acids During Mashing Dependent on Temperature, pH, Time, and Raw Materials.J.
What happens if mash pH is too high?
A high mash pH is said to be an obvious culprit of astringency in beer, as it is purported increase the extraction of tannins from grain husks.
Is it OK to stir moonshine mash?
Final Thoughts – Stirring the mash after adding the yeast is not a good idea. You risk disrupting the fermentation process that turns sugar into alcohol. Instead, make sure your mash has the optimal conditions for the yeast to thrive. : Do You Stir Mash After Adding Yeast? 4 Things To Know