Where can I find the fermentability of ingredients?

[ScottM]

I'm struggling to find the fermentability %age of spraymalt and other ingredients. Anyone know anywhere I can look them up?

I [/i]think[/i] muntons extra light spraymalt is 80% but I can't find anything concrete on it.

Thanks

 

[RobWalker]

It's on your yeast. Attenuation is the % of how much of the sugar you extract will be fermented. Light Spraymalt is about 1.044 btw

As for grains, Original Gravity potentials are listed here; http://www.byo.com/resources/grains 1lb grain in 1 gallon water. So for a 5 gallon batch, that's how much 5lbs would give you in gravity points - just adjust as necessary.

Calculator software is good for this, beersmith lists all of these as standard and predicts the attenuation for you.

 

[ScottM]

I'm thinking I may have asked the wrong question. It's the amount of fermentables in the products that I am looking for so that I can calculate the expected FG based on a yield.

For example, if extra light spraymalt was 80% fermentable and had a yield of 1.045 this would give an approx FG of 1.009. (80% of 45 = 36. Drop of 36 points from 1.045 = 1.009).

What I'm trying to nail down is the %age for ingredients. I'm not sure exactly what to search for. I did have a look on the muntons spraymalt pack and it didn't mention anything.

 

[RobWalker]

What I'm saying is that doesn't come down to the malt itself, it's determined by the attenuation of the yeast you use, which is a measure of the percentage of the sugars the yeast will convert to alcohol in malt. Different strains can work through the tougher sugars.

http://byo.com/resources/yeast

WLP001 can give you as low at 67% attenuation with malt, which will leave residual sweetness. WLP060 can ferment up to 80% of the malt, giving you a drier beer. That's where it comes from, not in the ingredient itself. It can also be affected by fermentation temp and whatnot.

Other simple sugars will ferment out dry (1.000 or below) given adequate conditions. :)

 

[anthonyUK]

Isn't the attenuation still a percentage rate of the fermentability though.
Malt is not 100% fermentable hence the residual flavour and Lactose is used to add sweetness as it is also not 100% fermentable.

 

[RobWalker]

The attenuation is how much of the sugars as a percentage in malt specifically that your yeast can eat up. It is a percentage of fermentability, but that's how you calculate your expected FG and OG, using the Potential Gravity of the type of malt in that table to calculate your starting gravity, and then calculating how much of that reading will be converted to alcohol by the yeast, which is the attenuation specific to the yeast strain you are using.

There's no need to figure out how much of the malt sugar is actually fermentable as an ingredient and regardless of what yeast you use, it's about 80% as that's what the highest attenuating yeast strains can achieve without pilsner enzyme etc. How much is actually converted during fermentation depends on the yeast strain. So if I started with 5 gallons of beer at 1.048, 80% attenuation would leave me with 1.009, 70% attenuation would leave me with 1.014.

Don't get flavour confused with sweetness - wine ferments dry and still has flavour. The reading above 1.000 is residual sugar which can account for flavour, but by no means would it be flavourless with a gravity reading below 1.000. Also, lactose sucks for sweetness, it's really for body and mouthfeel more than anything.

 

[ScottM]

This is really confusing me then. Why can I use the beer calculus calculator to work out an OG and an FG without telling it what yeast I am using? That's what I want to do.

http://beercalculus.hopville.com/recipe

The only reason I'm struggling with Muntons Extra Light Spraymalt is that it isn't in the list. Any other ingredients chosen tell me the amount of fermentables in it and the %age. Light DME is what I used to guess what the extra light spraymalt would be. Different malts have different potentials according to that with absolutely no regards to the yeasts being used.

Not really sure how else to explain what I am looking for. In that site I've linked to it's listed under "yield".

 

[RobWalker]

It's under Extra Light Dry Extract - calculators don't use brand names. And you can't get an FG without choosing a yeast because the higher or lower the attenuation, the different FG reading you get. It gives you a decent guess if you don't input a yeast to that calculator.

The percentage you are reading is the percent of the grain bill it makes up, not how much of it ferments. Brewers do this rather than using weight so they can up and downscale batches easily.

They have different potential gravities because that's how much sugar is in them per gallon or whatever specific to the type of malt used, not how much ferments per say. You get your wort - sugary water - and that has a gravity reading based on the density of sugar in the solution, and that's your OG.

You may want to read up on this stuff a bit if you're calculating recipes, it takes time care and knowledge to plan a good un!

 

[ScottM]

Here's a quote from another forum that I found via google when I was searching for an answer...

There is no reliable way to accurately calculate FG. Some people use the attenuation rating of the yeast, but that's really for comparing one yeast to another. The FG you achive is far more dependent on the fermentability of your wort than the rating of the yeast. If you mash at a high temp, or use an extract high in unfermentables, or use a lot of crystal malts in your recipe, your FG could be far higher than you'd expect it to be. If you mash at low temps or use highly fermentable sugars in your wort, you can easily exceed the rating of the yeast. You can certainly use the yeast rating as a WAG, but don't be surprised if your real FG is higher or lower than that.

That's how I understood it. The fermentability of the wort is a better way to calculate the potential FG. The different yeast just changes whether or not you reach that potential.

To further this I would take the following as being the case......

If you had an OG of 1.045 with an 80% fermentable wort, that would be a potential FG of 1.009. If a reasonably high attenuation yeast was used this would probably ferment out to 1.009 or therabouts, if a lower one was used the FG would be higher than predicted. If it was a wine yeast I would guess it would ferment past the 1.009 down a little lower, similar to it going past 1.000.

When doing the calculations in juice based wine or cider it's very easy as the sugar quantities are listed on the ingredients and you simply add the amount of sugar you add. With sugar being 100% fermentable the calculation is a doddle. It becomes more difficult when I don't know the amount of fermentable sugar in spray malt. Some places are saying 80% some places are saying higher, some lower. The amount of fermentable sugar is what I'm looking to find out in all the ingredients I use so that I can work out potential FG.

Hope that clarifies what I am after :)

 

[ScottM]

Looking at the beer calculus site again it would appear to just assume 75% attenuation until a yeast is chosen, as you said, so it's not really accurate either as it suggests that a wort made of 100% sugar will ferment to the same FG as a wort made with 100% English Crystal.

I could be onto a more accurate calculator afterall, if I can find the damn ingredients

 

[RobWalker]

Ah, I get you.

As far as your extracts go if you can't find it online you could email the company and ask, I'm sure they would give you some idea. There won't be a massive difference between brands - after all, they need the highest OG possible when they mash - more extract to sell that way.

I wouldn't be against working from 80%, as the old saying goes, "as long as it makes good beer."

I see what you mean about the calculator - not sure if beersmith2 can account for ingredients that ferment dry. That's weird, never noticed before. Although I suppose part of that is because the best way to get your FG is to measure it after brewing :

Good luck!

 

[ScottM]

Ok I'm getting somewhere.

The "Yield" on the beer calculus page seems to be what I was after....

Sugar PPG = 46
DME PPG = 44

Therefor DME = (100/46)*44 % fermentables

DME = 95% fermentables

Which is exactly what the "Yield" says it is.

My current calculator works based on the standard 75% attenuation, all I need to do now is make the attenuation an option and I'll be able to predict more accurate alcohol levels

This gives me a reasonably accurate OG and an adjustable FG.

 

[ScottM]

Ok, now this is all theory but here goes........


From reading around it would appear DME is between 70 and 80% normally fermentable sugar. This means that the lighter DME would be around 80% easily fermentable and the darker stuff would be around 70% easily fermentable. I'm fairly certain this is where the attenuation values of the yeast comes from. My thinking is that the attenuation of yeast is based on the average amount of easily extractable sugar in a wort. Some yeast strains are obviously produced to take advantage of more complex sugars and therefore they will eat into some of the not so easily fermentable sugars.

From this it would appear that everything other than extract/liquor can be taken as 100% fermentable with regards to their sugar content.

Here is a few working examples of my theory........

Extra Light DME - Yield 95% and easily fermentable sugar content 80%

1lb in 1 US gallon (to keep it simple) will give 1.044 OG

if a standard strain of yeast is used that only eats the baseline sugars (normally referred to as 75%) because it is extra light the actual amount of sugar available to the yeast will be 80%.

100-80 = 20%. 20% of 44 = 8.8

Therefore the FG of this wort will be 1.009

Based on the OG and FG the alcohol content would be 4.52%


If my thinking is correct then sugar alone would be completely different. Discount the fact that nutrients are required etc, for simplicity it's just sugar, water & yeast.

1lb of sugar in 1 US gallon of water = 1.046OG

As I understand it a standard yeast strain (75%) will actually take sugar down to 1.000 and a more aggressive strain would take it even lower (ie wine yeast). My reason for thinking this is that the basis of the yeast attenuation is on wort/extract/allgrain liquor rather than just straight sugar. This will be the reason that recipes with just sugar tend to ferment a fair bit lower than those which use DME etc (sorry if I'm stating the obvious here just trying to lay out my thinking).

Therefore I think it can be accepted that a very high percentage of sugar will be fermented to alcohol. In fact for this example I'm going to assume 100% so the FG is going to be 1.000 with a standard strain.

OG 1.046, FG 1.000 alcohol content 5.99%


This leads me to another question regarding the more aggressive strains of yeast. What do they take out of the water to lower the SG of it? Does water have nutrients, sugars etc? Or is it the minerals that get taken out to go as low as 0.990?


Anyway, this may be a load of ******** in the eyes of most but it makes perfect sense to me and I'm going to be using all this information in my calculations from now on :)