So, for the last few batches of beer, I have been overshooting my FG. I used BS3 to formulate my recipes and have brewed these multiple times. I also use a tilt hydrometer and, because I’m pretty anal, I verify with a hydrometer that reads correctly. Calibrated in RO water. I recirculate using a HERMS. I have not changed my processes for these recipes. I use iodophor to sanitize everything. Example 1) FG 1.009 but I actually hit 1.002— Ex. 2) 1.011 but hit 1.004 Both beers are 7 points over what they should be and what they have consistently been.
Suffice it to say, I am pretty clueless as to what is causing this.
Has anyone had this happen to them and what are some possible causes?
Are these recipes you’ve brewed before? How did you determine what FG they should be? Let’s start there. If your target was valid, then we can start looking for a cause.
As I stated in my post, I use BS3 to formulate. I’ve brewed these 2 recipes multiple times with repeatable results down to the design FG. Ex. 1) OG 1.051/FG1.009…Ex. 2) OG 1.050/FG1.011
I may have misspoke when I said example, these are my estimated numbers and as stated, I’ve always hit my numbers right on mark.
You say you haven’t changed your process. Has anything changed, possibly? Different sack of base malt? Is there any chance your thermometer has gone wonky and you really did change the mash temperature? Just grasping at straws.
Anything is possible but I’m precise with my brew day. I go off of my recipe to the tee, times, temps and notes. I have and do use different grains but always input the specific info from each grain, which happens to be pils for these 2 examples, into BS3. Again, I must say that I’m pretty anal about calibrations. I will calibrate my pH meter before each brew day. It only takes a few minutes anyway. My system is a plug and play electric and the temperature setting is set and forget. I don’t think this is a case of increased efficiency because my OG has not changed. Truly at a loss to explain the WHY!
That makes me wonder more about the malt, was it in fact a different lot? If your process is tight, the only immediate thing that cones to my mind that could affect fermentability is the malt itself being enzymatically “hotter.” If that’s not it… You got me stumped, but I’d be going nuts in your position, too.
Assuming all your SG readings are accurate, it is possible that you may have a wild yeast infection problem. Beersmith calculates FG based on the average attenuation number in the particular yeast’s profile. Many wild yeasts can breakdown complex sugars unfermentable by regular beer yeast. What does the finished beer taste like, beside being much drier than previous batches?
BTW, iodophor or starsan will not kill wild yeasts. Check your hoses, any recessed areas in the fermenter, and transfer equipment. You will need to use caustic or bleach to kill them. They are also harbored in areas with beer stone, which can be removed with acid.
Other than being drier, brutish, absolutely nothing. Having the same people usually drink my brew and having asked them(novices, non beer making friends) they claim it tastes no different. I could agree with your assumption that it might be a wild yeast infection but I’m a stickler for cleanliness and sanitation. Again, idophor for sanitizing. I break down my basement brewery about every 5 brews. Obviously cleaning in between brews. When I say I break down, what I mean is a complete tear apart of equipment, cleaning and sanitizing. walls and floors get a thorough scrubbing, hot water rinse and iodophor. IDK!
Are you certain that iodophor does not in fact kill wild yeast? Can you show me something that proves your statement? I’ve been under the understanding that it in fact does kill wild yeast and mold whereas starsan will not…
AFAIK all the evidence to date is that iodophor, like bleach, kills everything, while acid anionic sanitizers are not effective against fungi, yeasts, and spores. I’ve seen some pushback against this idea recently on at least one forum but without supporting documentation. But it is also true that you can’t sanitize what’s not mechanically clean, and gav is correct that beerstone deposits can harbor biological material that is inaccessible to standard sanitizer applications. I regularly use an acid for this purpose. Identical to but far cheaper by the gallon jug than brewery products is milkstone remover, if you have access to a dairy supply (or stocked by Tractor Supply or Farm and Fleet in certain areas.) The acid will loosen the oxalate deposits which then can be removed by PBW, etc. Good to just incorporate it into the protocol from time to time.
One of the greatest things about BeerSmith is that it enables the brewer to control the software so it reflects results that represent expected results from their equipment and process. The estimated values are reflective of user inputs. Once you enter your equipment profile and brew a few batches, you need to fine tune the profile. If you don’t, you will continue to miss your mark, because you haven’t properly defined it in the software.
Agreed! I’ve done that early on. Again, these are tried and true recipes that have consistent results and brewed many times with the expected repeatability.
Although it is more expensive than milk stone remover (a very good relatively inexpensive product, we used it on the dairy farm where I grew up) a solution of 1 oz of Star-San in a gallon of water is also good at removing beer stone. SS Brewtech recommends this for passivating their fermenters. I have used it in my boil kettle to get rid of beer stone (since I have a lot of it around and want to use it up before moving on to milk stone remover) and it works well. I let it sit for about 5-10 minutes and can easily scrub off the remnants of beer stone from my kettle and false bottom with a Dobie pad.
That doesn’t really matter in an absolute sense. It’s just a way of comparing one yeast to another. I can get anywhere from 60-90% attenuation with the same yeast depending on wort.
