How to reach the right OG?
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Hex
Well-Known Member
You should add more fermentables near the end of the boil to reach your Original Gravity.
That adjunct will typically be in the form of invert syrup, cane sugar, Extra Pale Dry Malt Extract, etc. depending on the recipe.
You can also add it after primary fermentation settles down as long as the solution is sterile (boiled).
You can also boil longer to concentrate the wort.
That adjunct will typically be in the form of invert syrup, cane sugar, Extra Pale Dry Malt Extract, etc. depending on the recipe.
You can also add it after primary fermentation settles down as long as the solution is sterile (boiled).
You can also boil longer to concentrate the wort.
Guys, you're giving advice and we don't even know what kind of brewing he's doing...If he's doing ag or extract. You don't have enough information to be helping yet. If he's extract brewing for example his og could simply be off from insufficient mixing. Totally different animal that needing to mash, since he's not mashing...
hercher's the only one who's on track, asking for more info rather than throwing out our pet answers....how can we answer if we really don't know the question yet?
hercher's the only one who's on track, asking for more info rather than throwing out our pet answers....how can we answer if we really don't know the question yet?
Hex
Well-Known Member
He states (1073 with temperature correction) so I assumed that he was taking his reading from a sample taken near the end of the boil duration. Mixing in this situation is a null point, because the wort is boiling, right?
It may be as simple as not accurately measuring starting/finishing liquid volumes. If your boil off rate is not precise, and your water volume is not accurate, you will never figure this problem out.
It may be as simple as not accurately measuring starting/finishing liquid volumes. If your boil off rate is not precise, and your water volume is not accurate, you will never figure this problem out.
Hex
Well-Known Member
Assuming that you are accurately measuring the mass of your fermentables:
Accurate liquid measurement of the pre boiled wort determines the accuracy of the pre-boil OG.
Accurate liquid measurement of the post boiled wort determines the accuracy of the post boil OG.
The mass of the sugar in solution remains the same before and after boil...
There are many potential solutions, but knowing your brewery by being a data-taking scientist will help.
Some people (including me) don't usually care about hitting the numbers. Often, I don't take any readings, and make good beer, but that success is based on a lot of practice, and a good notebook.
Accurate liquid measurement of the pre boiled wort determines the accuracy of the pre-boil OG.
Accurate liquid measurement of the post boiled wort determines the accuracy of the post boil OG.
The mass of the sugar in solution remains the same before and after boil...
There are many potential solutions, but knowing your brewery by being a data-taking scientist will help.
Some people (including me) don't usually care about hitting the numbers. Often, I don't take any readings, and make good beer, but that success is based on a lot of practice, and a good notebook.
Hex
Well-Known Member
Using a simple OG, FG, ABV calculator, you can demonstrate to yourself that an inaccuracy in post-boil volume of only one half gallon will change your OG from 1.073 to 1.080.
hercher said:
Here is:
INGREDIENTS
Light Dry Malt 1kg
Black Rock Light Liquid Malt 1.5kg
250g Brewcraft Brewing Honey
50g Crushed Black Grain
40g Hallertau Hops
25g Goldings Hops
Safbrew T-58 yeast
Soft Brown Sugar 400g
i boiled the lme with hops for 35 min,
Put the grain into cold water then bring it to boil and remove the grain just before boiling point,
Add it to the wort with the liquid malt and sugar and honey and boil it for a other 5 min,
Then strained it to my fermenter and add water up to 15L
That's it
I figured it was going to be this issue, and not what the other's were suggested, but until you told us you were an extract brewer all folks could do (ridiculously) speculate.
We get this question 3-4 times every day, so you're not alone. And in reality, nothing's wrong.
It's a pretty common issue for ANYONE topping off with water in the fermenter (and that includes partial mashes, extract or all grain recipes) to have an error in reading the OG...In fact, it is actually nearly impossible to mix the wort and the top off water in a way to get an accurate OG reading...
Brewers get a low reading if they get more of the top off water than the wort, conversely they get a higher number if they grabbed more of the extract than the top off water in their sample.
RM-MN has a great analogy;
When I am doing an extract with grain recipe I make sure to stir for a minimum of 5 minutes (whipping up a froth to aerate as well) before I draw a grav sample and pitch my yeast....It really is an effort to integrate the wort with the top off water...This is a fairly common new brewer issue we get on here...unless you under or over topped off or the final volume for the kit was 5 gallons and you topped off to 5.5, then the issue, sorry to say, is "operator error"
More than likely your true OG is really what the recipe says it's supposed to be. And it will mix itself fine during fermentation.
And just use the number it says in the instructions as the true OG, because it will be.
So the answer is, relax and do nothing.
Honestly, no matter how well you THINK you mixed, it's not enough...
It's an extract batch, as long as you have your correct final volume in the fermenter, you can't miss your gravity.
When making an extract batch you are not converting any starches to sugars, it's already done for you. All you are doing is adding an amount of water (actually 2 amounts of water-boil and top off) to a final volume (which the og is calculated for) the only way to actually miss your og on an extract batch were if you had an in the fermenter volume different than the recipe called for.
If you have whatever the recipe calls for as your final volume, the OG of the recipe is correct DESPITE what your hydromter might say.
Good answer
Take it easy brother. I wasn't (ridiculously)speculating anything.
I don't know jack about extract. and since he didn't specify either extract or AG I gave an answer of something I know a little about and I gave budchx the benefit of the doubt that if he could use that info he would, if he couldn't, he wouldn't. Certainly he would not try to mash at a lower temperature if he wasn't mashing.
Depression
Member
jetmac said:
Brrrooother!!!!
Depression
Member
budchx said:
Mash at the right temp. Mashing Too high/Too low is the most common AG cause of a funky OG, Brrrroother!
Take it easy brother. I wasn't (ridiculously)speculating anything.
I don't know jack about extract. and since he didn't specify either extract or AG I gave an answer of something I know a little about and I gave budchx the benefit of the doubt that if he could use that info he would, if he couldn't, he wouldn't. Certainly he would not try to mash at a lower temperature if he wasn't mashing.
Exactly how would mashing at a lower temp give him a different OG?
I haven't ever noticed changes in efficiency based on my mash temp.
Hmmm...I don't know that I can explain it exactly because I am not a chemist, but I'll try. You can also find this information in a brewing book somewhere.
From Mr. Wizard at BYO magazine:
The sweet beer/dry beer question focuses the discussion to one area, and that is the activity of two enzymes: alpha- and beta-amylase. The important thing to know about these enzymes is that they both attack starch but in different ways.
Starch comes in two forms. One form is called amylose (about 25 percent of barley malt starch) and contains no branches; it is simply a string of glucose molecules connected like links of a chain. The second form is called amylopectin (about 75 percent of barley malt starch), and this form does contain branches. Imagine a chain where one of the links is connected to two links and each one of these links is then connected to one other link. Now imagine this scheme where a new branch pops up after every 25 to 30 unbranched segments. The result is a complex structure originating from a single point. Think of a big oak tree with hundreds of branches. It might help to understand what follows if you draw a stick drawing of amylose and amylopectin.
Amylose and amylopectin have ends called reducing and non-reducing ends. The names are not that important, except that the ends of the branches in amylopectin are all non-reducing ends and its "trunk" is the only reducing end. Amylose is easy because it only has two ends, and one is reducing and the other is non-reducing. When either one of these molecules is split, there is a reducing and a non-reducing end formed.
Amylose and amylopectin are made up of chains of glucose, a simple sugar. They are the only two molecules that alpha- and beta-amylase do battle with in a mash. To get to the heart of the question, I need to give some basics on the two enzymes.
Beta-amylase: 1) has optimal enzyme activity between 140° and 149° F; 2) attacks chains of glucose from the non-reducing end only to form maltose, a simple sugar made up of two glucose molecules. Beta-amylase chews through a chain of amylose like Pac-Man eating dots two at a time; 3) cant break a branch point in amylopectin; 4) is nicknamed the "fermentability" enzyme.
Alpha-amylase: 1) has optimal enzyme activity between 155° and 158° F; 2) randomly attacks chains of glucose and converts large molecules into a bunch of little chunks; 3) cant break a branch point in amylopectin; 4) is nicknamed the "liquefaction" enzyme.
If you want a full beer with a low fermentability, steer your mash away from beta-amylase. This means mash in toward the upper end of the alpha-amylase temperature window and keep the mash as short as possible while still achieving a negative iodine reaction (no black-blue). Although alpha-amylase does manage to produce some fermentables due to its random activity on starch, the higher temperature minimizes the likelihood of rogue molecules of beta-amylase running around whacking off chunks of maltose from the non-reducing ends of starch molecules.
This is kind of like chopping veggies. If you dont like small bits of evenly sliced carrots in your soup, dont invite the local chef who goes chop-chop-chop at 120 chops a minute; instead invite the Boy Scout who goes whack-whack-whack and moves on to the next carrot.
One technique that will further cripple beta-amylase is a thin mash. Enzymes are more stable when they are latched onto their substrate (the substance they act upon), and a thin mash leaves a higher proportion of the enzymes floating around looking for their substrate. This is one of the reasons enzymes dont have a single optimum temperature. In any case, if you use a thinner mash, you will produce fewer fermentables than in a thicker mash (up to a point you gotta have water to make wort!).
If your objective is to make a very fermentable wort for a dry beer, things get a little more complex. For starters you really want beta-amylase to be a happy camper. Mash in cool, say around 140° F, and give your mash a good long hold. This will allow beta-amylase to chop up all the amylose and the tips of the amylopectin branches. This is a good start, but there are still a lot of glucose molecules tied up in amylopectin. The only way for beta-amylase to make more maltose is for alpha-amylase to "open-up" amylopectin molecules (the starch that has no branches) with a few random whacks.
If you wait around long enough, alpha-amylase will start to open up amylopectin. Remember, its optimum activity is around 158° F, but it still is active at cooler temperatures, though its much slower. As alpha-amylase opens up amylopectin, beta-amylase starts tearing into the new non-reducing ends and freeing more maltose. At the end of the "fermentability" rest, the mash should still be heated to around 158° F to achieve a negative iodine reaction. Bud Light is made using this type of mash profile, and the mash lasts for more than three hours. Unlike many other light beers, Bud Light wort has a low concentration of unfermentable carbohydrates and does not use exogenous enzymes (store-bought enzymes) in the process.
Another way to get alpha- and beta-amylase working together is to slowly increase the temperature from 140° F, after your initial 30- to 45-minute rest, to 155° to 158° F. This is easier said than done at home because small batches are harder to control than larger ones, but in commercial breweries using steam-heated, stirred mashes, this process is easy. The most common way of slowly increasing the temperature is to heat from 140° to 142° F and rest, then from 142° to 144° F and rest, and so on. This stair-step process is much easier to control than a continual rise from "A" to "B" because most mashing vessels are designed to heat at a constant rate and simply heating slower is not an option.
Stair-stepping can be done at home by carefully adding hot water a little at a time or alternating between heating steps and rests. The hard part is getting a good temperature reading while stirring and heating. If you are using gas or electric heat, dont crank the burners up too high because temperature overshoot will most likely follow.
Some brewers do a bit of both. They mash in for a beta-amylase rest and then rapidly raise the temperature to the alpha-amylase rest to avoid too much dryness in the finished beer. Other beers mash in even cooler for beta-glucanase or limited protease activity. This is where the topic of mashing starts to get big.
One word of caution. Many brewers, when first starting out, get what seems like an ingenious idea that will not work. The idea is start out at 158° F to let alpha-amylase do its thing and then to cool the mash down to le beta-amylase do its thing. This wont work because heat denatures enzymes at temperatures above their optimum, and denaturation is permanent.
Here is a link to a chart from brewsupplies
uncommonsense
Well-Known Member
Keith_Mahoney said:
Ya dosnt mash temp (if its within sacc rest temp) effect how fermentable the sugers are.
You still haven't answered my question yet.
Yeah, yeah, yeah. You can post an article with a lot of big words that sound like John Palmer made them up.
Everything you have posted in this thread is about how to hit a specific FG (Final Gravity as in post fermentation). The OP was asking about hitting his OG (Original Gravity which is post boil but prior to fermentation)
OOps. Nice catch, I guess I must have been tired and misread OP's question.
That would have been a much simpler answer.
As far as the big words, I did specify it was from Mr Wizard at BYO magazine, not my words, and you wanted specificity. But my misreading has wasted alot of time.
While I do predominantly AG or PM brews, I still have this issue as my apartment limits me to partial boil, and having to top off. I'm sure I'm not the first to do this, but I've come up with a trick that seems to work for me. I take gravity readings of the wort after I've chilled it, but before I top it off, and then calculate my OG after top off based upon the ratio of dilution with top off water. That way, the mixing issue is completely out of the equation. If you have 2.5 gallons of wort, and top off with another 2.5 gallons of water, the final OG reading will be half of what the 2.5 gallon wort read. Not so helpful with this brew, but hope that helps with future brews.
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