Topping off wort with water

[Gold_Robber]

I have read a few posts from experienced brewers at this forum that say it's all good to top off wort with cold water if it is short.

What if someone boils away 75% of the wort, can they simply add it back in cold water with no consequence? How much wort can be brought back by cold tap water before any noticeable changes occur? TIA

 

[emmdubb23]

I have read a few posts from experienced brewers at this forum that say it's all good to top off wort with cold water if it is short.

What if someone boils away 75% of the wort, can they simply add it back in cold water with no consequence? How much wort can be brought back by cold tap water before any noticeable changes occur? TIA

Topping off with pre-boiled or distilled water is fine, I would re-think your process if you are boiling off 75% of your water. It shouldn't overly effect the finished product unless your sugars caramelized during the cook.

 

[bja]

What if someone boils away 75% of the wort,

Why would someone do that?

 

[Gold_Robber]

It was just a hypothetical - the 75% loss of wort. It never actually happened...LOL

On my last batch, I made a 1 gallon batch, I was really short, not 75% but still really short. I did top off with cool tap water but am concerned that I had to add too much and the batch will now be ruined. I'm learning a ton, if nothing else.

 

[duboman]

It was just a hypothetical - the 75% loss of wort. It never actually happened...LOL

On my last batch, I made a 1 gallon batch, I was really short, not 75% but still really short. I did top off with cool tap water but am concerned that I had to add too much and the batch will now be ruined. I'm learning a ton, if nothing else.

Did you take a gravity reading after topping off and was it correct? Ideally you pay closer attention during your process so you avoid these issues............Understand what your boil off rate is and compensate for it prior to boiling so you are using less top off water.

 

[Gold_Robber]

Actually I don't have a hydrometer. I know, it's like a priest not have an alter boy. I will buy one next week - a hydrometer, not an alter boy.

If I see that I am short of wort, just before I begin the boil, I guess it would be ideal to had hot water at that point. Common sense but being a newbie sometimes I get caught up in so many things during my brew day that such a simplistic thing gets lost.

Thanks

 

[ACbrewer]

Wow several questions have popped up here.

1. Often extract brewers brew on a stove (like me) and only boil about 2 to 3 gallons of their 5. Opinions differ, but I've found that if your tap is drinkable, you can top up to your target volume without any problems. Others think you should boil it first. >shrugg< Again, I've had no sanitation issues, but I suppose clorine could be an issue.

2. It is better to have your target OG than target volume, unless your volume is really short - I mean if you started with 1 gallon and end with 1/4 gallon, perhaps adding water is really called for, and shouldn't be a problem. I can see that even with my stove, my boil off is probably 16 oz but it might be more, (see, not measured, so I don't really know) But a pot could loose a lot of water - most AG people figure 1 gallon per hour on their propane. If it were 1/2 gallon per hour on electric, at 1 gal preboil volume, that is a lot.

3. When you top up, you need to stir/agitate it together to get the liquids to mix, otherwise you have a dense bottom and a less dense/more watery top. When you take a OG this can scew with your numbers. - I take bottom samples, and once had and OG of 1.070 on a 1.048 recipe. Not mixed well. Does mixing matter in the end? no the difusion and yeast action and co2 outgassing will mix for you, but it screws with your measurements.

 

[Revvy]

What if someone boils away 75% of the wort, can they simply add it back in cold water with no consequence?

You're not boiling 75% of the wort away, you're boiling 75% of the WATER away, the sugar is just going to be more concentrated, and therefore the density, or GRAVITY is going to increase, by EXACTLY the amount that that amount of water added back or DILUTING you boiled away.

Think about it like this, but the numbers are pulled out of my ass.

If a 5 gallon batch of x beer is supposed to be 1.030 but you boiled away a half gallon extra of water so rather than 1.030 your beer is 1.040. That 1.040 gravity is because the wort is now a half gallon THICKER or actually denser, than if that water was in there still.....so in order to regain that gravity, you simply have to dilute that wort by the amount of water you are missing.

Go to this gravity calculator and you will see what I mean. I think the bottom one would be the applicable one. I like the one on beersmith better.

A can of extract undilluted like in a cooper's can has an insane gravity and IBU (If you read this post I talk about the IBU's of a can of prehopped cooper's extract, because new brewers get panicky when they read on the website the IBU list for the extract,) but when you add water you are dilluting it all down to a resonable amount.

If you add too much water the gravity will be low by that amount as well, so you have to BOIL AWAY that amount and the gravity/density will restore as well.

 

[Gold_Robber]

Revvy,

I think that is the key statement - "You're not boiling 75% of the wort away, you're boiling 75% of the WATER away".

As a new home brewer I wasn't understanding the boiling process well enough - water vs wort. This changes things drastically in my thinking.

Thank you, and the rest of the members in this thread, for clearing this up. And for the valuable links!

 

[Revvy]

Revvy,

I think that is the key statement - "You're not boiling 75% of the wort away, you're boiling 75% of the WATER away".

Yeah, you're forgetting that wort, like what 99% of the matter on this planet is made up with some percentage of water.

And the more I was thinking about what you mentioned in the pm to me, making gravy everything still applies.

When you're making a gravy or a reduction of any sort, when you thicken (whether or not you use a thickening agent to help) you're still boiling away water, which is CONCENTRATING the flavor and also carmalizing the sugars often as well. If you get it too thick and don't scorch the heck out of it, you just add a little more water or wine or stock to thin it (dilute it.)

Think about deglazing a pan to make a pan sauce or something. What is the fond, the brown bits at the bottom? Caramalized/reduced sugars from the mailard reaction during browning. When you deglaze with a liquid you're breaking that back down into liquid form.

It's all the same principle. But with wort we can use something to read the gravity easily to see this. But with food, you'd probably need a mass spectometer and to test the food at each phase to see.

 

[BetterSense]

I regularly come up deliberately short on volume. After the beer is cool and in the fermenter, I take my gravity sample, calculate my top-off and then top up to exactly the O.G. I wanted. As others have pointed out, you can't really take a gravity sample after top-up unless you stir very well. I typically use distilled water because it's only a small volume.

 

[mdgagne]

Boiling away 75% of the water from your wort isn't going to ruin your beer; however, it will likely change the beer. You're going to reduce hop utilization with a higher gravity wort so the actual IBU will be different then the recipe. You're also going to change the amount/type of mailard reactions you get during the boil which changes the flavor of the beer. For malt-forward this is likely good, for hop-forward beers it may be bad.

To what extent this changes the beer, I don't know, I've never experimented much with the concentration of my wort.

 

[Gold_Robber]

Revvy,

I am not a top chef but if you add the same amount of water as was reduced (evaporation), in making of the gravy, the 'gravy' would taste thin...I think ..lol But the principle, as you stated, is the same.

I do understand your point about water reduction in the wort mixture and the density of the sugar increasing and then adding the same amount of evaporated water to end up with the required sugar density. Wort, as you also mentioned to me, deals with highly concentrated sugars which makes it unique.

 

[Revvy]

Boiling away 75% of the water from your wort isn't going to ruin your beer; however, it will likely change the beer. You're going to reduce hop utilization with a higher gravity wort so the actual IBU will be different then the recipe. You're also going to change the amount/type of mailard reactions you get during the boil which changes the flavor of the beer. For malt-forward this is likely good, for hop-forward beers it may be bad.

To what extent this changes the beer, I don't know, I've never experimented much with the concentration of my wort.

I've found that this old "chestnut" is a bit overblown in actuality. In truth any change in hop utilization is going to actually be so subtle that for the most part any taste perception is not going to be all that noticeable. It's been discussed even by John Palmer, who totally re-evaluated what he wrote about hop utilization after attending a seminar on hops several years ago, that HUMAN TASTE PERCEPTION of hoppiness is not as sensitive as most people think; that we maybe able to distinguish between a gap or 10-15% ibus or so Such as a 15 ibu beer and a 30 ibu beer, BUT we really cant perceive a small difference in ibus, let's say between a 15 pilsner and a 17 Ibu pilsner.

And the actual difference in hop utilzation like you're talking about is really not that many ibus difference.

 

[Revvy]

Revvy,

I am not a top chef but if you add the same amount of water as was reduced (evaporation), in making of the gravy, the 'gravy' would taste thin...I think ..lol But the principle, as you stated, is the same.

I do understand your point about water reduction in the wort mixture and the density of the sugar increasing and then adding the same amount of evaporated water to end up with the required sugar density. Wort, as you also mentioned to me, deals with highly concentrated sugars which makes it unique.

I didn't say it's EXACTLY the same, BUT if a recipe says to reduce a volume by half in boiling, and that's 2 cups of liquid in a pan reduced to 1 cup, AND THEN you add a cup of water back to it to go to the original volume, it may still then taste the same as before you boiled it. Depending what the base liquid your boiling is, if it's mostly water, then I betcha it would be very similar in principle.

I'm thinking that if you were making a pot of chicken soup, which began as nothing more than water, a chicken, some herbs and veggies, tasted it initially, boiled a cup or two away, tasted it again, added the same amount of water back to it, and tasted it again. First tasting and third tasting would probably not be too different.

And I bet if you took a gravity or ran it through some sort of spectra or chromata graph the pre boil and post boil with water would have similar numbers of some sort.

But like I said it's just a rough analogy anyway, you can see it in the numbers on a dillution calculator and with multiple gravity readings in a brew.

 

[BetterSense]

For context, I have not noticed a difference in hops utilization when I boil my hops in plain water (when I make extract batches) or when I boil them in wort (when I make all-grain).

 

[bobbrews]

If you were at the beach and you really wanted a nice refreshing lemonade, would you:

a) Buy from the guy who was diluting 1/8 cup of 100% natural, fresh lemonade concentrate with 12 oz. of water?

or...

b) Buy from the guy who was squeezing the juice of fresh lemons into your cup with the appropriate amount of water & sugar?

FYI - You can reach a full, rolling boil of 5-6 gallons on a gas stovetop. Probably not an electric one, but it is certainly possible on a gas range.

 

[Revvy]

If you were at the beach and you really wanted a nice refreshing lemonade, would you:

a) Buy from the guy who was diluting 1/8 cup of 100% natural, fresh lemonade concentrate with 12 oz. of water?

or...

b) Buy from the guy who was squeezing the juice of fresh lemons into your cup with the appropriate amount of water & sugar?

FYI - You can reach a full, rolling boil of 5-6 gallons on a gas stovetop. Probably not an electric one, but it is certainly possible on a gas range.

What does this have to do with the OP's question? What does it have to do with any of this discussion? This sounds more like a PREFERENCE thing than what happened to the op by boiling too much water in his wort?

What does cooking with gas have to do if a brewer Can't switch from electric to gas. I would love to cook on gas in my condo, but can't have it.

 

[bobbrews]

I don't know Revvy, why don't you mull it over

 

[Revvy]

I don't know Revvy, why don't you mull it over

Since it doesn't seem pertinent to the discussion at hand, I don't think I'll waste my time. You can if you want. Have fun.

 

[freisste]

I don't even understand the comparison you are making...

Your "parallels" to brewing aren't entirely parallel. And both sound acceptable. Usually you use a metaphor to make things clearer, not more confusing.

 

[bobbrews]

It's just a simple question. It isn't rocket science. Which guy would you buy from if both prices were equal?

 

[freisste]

Either. In fact, probably whoever is cheaper. Like i said, both are acceptable. That's what makes your post confusing. It doesn't clear anything up. In the future, summarize what you are saying in the last sentence of your post if it is going to be ambiguous without the clarification.

 

[bobbrews]

So, assume you are the owner of a lemonade stand. And every morning, you boil a bunch of fresh made lemonade down to 1 liter to concentrate the flavor. You use some of the concentrate per cup, then top off with water to 12 oz, and sell the product to customers for the same price as the guy next to you making his lemonade to order with fresh squeezed lemons. Are you telling me that you will have the same quality product in the end?

 

[freisste]

Nobody here is boiling off 95% of their liquid. Try to stay realistic.

I can name a lot of practices that don't make sense if you take them too far. If I drink an entire liter of vodka in half an hour, I might die. That isn't going to keep me from drinking liquor because an appropriate volume is safe for consumption.

Last post for me on this thread.

 

[bobbrews]

Well you took it to extremes by adding your own %'s in there.

I was just pointing out that there is a difference in quality when it comes to topping off vs. full volume boiling. Whether or not you choose to accept it or not, that is your issue.

If topping off did not affect quality, then beers like KBS, Pliny the Elder, and Westvleteren 12 would all be topped off to save the breweries time, money, and effort.

 

[Revvy]

Anyway, staying to the questions/ question the OP asked on here and in private, even all grain brewers do this if they under shoot or over shoot their boil volumes, and consequently their gravity, that's why refractometers are so great to measure pre fermentation wort. A lot of times you're adjusting as you go along, like if you're brewing outside on a windy day and that normal hour boil where you usually get only a gallon of boiloff you get a gallon and a half..... Beersmith can show you what pre-and post boil gravities should be, so you can see if you're off during a boil, especially if you have a measuring stick or measurments etched on your kettle where you can see how much you're boiling off. If it's too low and you have too much wort in the kettle still, you boil a little longer, if it's too high and your down, you can add water in the kettle or you can wait til you rack over just like a top off batch.

And you won't really notice the difference in the end. It's a pretty common occurance, that's why most software has a dillution tool to begin with to help you figure it out.

 

[mdgagne]

I've found that this old "chestnut" is a bit overblown in actuality. In truth any change in hop utilization is going to actually be so subtle that for the most part any taste perception is not going to be all that noticeable. It's been discussed even by John Palmer, who totally re-evaluated what he wrote about hop utilization after attending a seminar on hops several years ago, that HUMAN TASTE PERCEPTION of hoppiness is not as sensitive as most people think; that we maybe able to distinguish between a gap or 10-15% ibus or so Such as a 15 ibu beer and a 30 ibu beer, BUT we really cant perceive a small difference in ibus, let's say between a 15 pilsner and a 17 Ibu pilsner.

And the actual difference in hop utilzation like you're talking about is really not that many ibus difference.

Based on the half-dozen or so articles I have read in the past year on late extract additions, I would have to disagree with your statement. Late extract additions have gotten more-and-more popular over the past few years. Although I have no experience of my own (I've been AG brewing for some time now), if I recall correctly late extract addition and its positive effect on extract beers is due to both hop utilization and mailard reactions. From a reproduce-ability standpoint, I think people that follow the recipe (including intended boil concentration) will produce a beer closer to the original than someone that boils at twice the concentration. Now, I'm not saying that hop utilization alone is the culprit here, I think it is a combination of both utilization and mailard reactions that change the recipe in a noticeable way. Whether this is a good or bad change probably depends on the recipe; however, I submit that it does change the flavor beer.

If you have experimented with this yourself and debunked those articles, I'll eat my words.

 

[masterfool101]

If you want to think about this logically, one would note that LME is nothing more than a wort with 80% of it's water boiled off (though, admittedly, this is often done in specialized circumstances, such as a vacuum chamber where they can achieve boil at a lower temperature and not affect the wort as much)

 

[mdgagne]

If you want to think about this logically, one would note that LME is nothing more than a wort with 80% of it's water boiled off (though, admittedly, this is often done in specialized circumstances, such as a vacuum chamber where they can achieve boil at a lower temperature and not affect the wort as much)

Yeah, I think that the vacuum is a big factor in how they avoid excessive caramelization and introduction of unfermentable sugars because they can boil at a relatively low temperature.