Am I expecting too high a starting gravity???

Hey, all....

I'm brewing again after five years of drinking out of a bottle!

I'm in the middle of my second five gallon batch today and I find myself wondering what kind of starting gravity to expect... For the first batch this morning I mashed 8 lbs of pale malt from Williams, plus about 3/4 lb of other malts. Temp 152-146 over two hours, ph at the start of about 5.5. I came out with a gravity of 50, and about 4.5 gallons. SG seems a bit low to me but maybe things have changed in the world of malt. I used to get really good conversion rates (I think)...

Anyway, any feedback would be great!

Thanks a lot, and BTW, what a great website!

jp

Ok, so I plugged the following into ProMash:

8 lbs pale malt
.5 lbs crystal malt
.25 lbs chocolate

4.5 gallon batch size

70% efficiency = OG 1.050

75% efficiency = OG 1.053

80% efficiency = OG 1.057

so you ain't doin' bad IMO... do you remember what your efficiency was the last time you were brewing??? Are you using the same system as before??? and FYI 10 lbs of grain @ 70% efficiency for 5 gallon batch is around OG 1.052, so if ya want to get that extra 1/2 gallon at your current efficiency/ gravity it will take another 1 1/4 lbs of grain...

hope that helps,
mikey

Yeah, Mikey, your information helps a lot. Especially the efficiency table… Is Promash a computer program?

I got out some old notes and, sure enough, I was getting SG’s of 60 or better from eight to ten pounds of grain when I was brewing before. So something’s definitely amiss. I’m using the same system- mash for two hours in ten gallon pot, insulated; sparge at 170 degrees (reheating the initial runnings) after a mash-out rest at 168 degrees; one-hour boil.

My second batch yesterday was even less efficient… I used the same recipe but changed one variable- I set the mash at 156 deg. instead of 152. Result was an SG of 44. I was bummed, so I had to drink some beer.

Three things were different with these two batches from my old operation:
1. I added 1 ½ tsp gypsum to the mash water instead of ½. I was going off some old PH strips…
2. I used grain crushed by Williams, rather than crushing my own (their crush looked just fine)
3. I started the mash before opening a beer… This, I believe, is very bad…

Anyway, both batches are now bubbling merrily away and all may be well in the end…

Thanks again, jp

I think your point 3 is the probable cause of the problem. The last time I ran out of homebrew, I also had an unusually low gravity from my "dry" mash/sparge.
Have you calibrated your hydrometer and thermometer? I know the paper scales you get in modern hydrometers can slip a little and cause them to lie.

-a.

Hey, ajf,

Yeah, I thought about that, but I have two hydrometers and three different thermometers, and get the same readings.

I'm starting to think that my old PH strips are no longer worth a damn, and I may have lowered my PH too much... or maybe not enough, although I added 1.5 tsp gypsum. My water comes right out of the ground and is pretty neutral if I remember rightly.

I, too, think the problem may be related to improper lurication of my gullet during the mash...

jp

I would actually lay odds on the crush...that's where I see the most variation in my efficiencies. I used to get really concerned about the pH, but have found my mash usually comes into line by itself (low buffered city water). I can't read the strips well, anyways.

Baron, thanks for the feedback. I've been wondering about that, too. I'm used to grinding in an old Corona grain mill (I mean, like, thirty years old. It's the one me ol' pops used to grind wheat in fer me mum to make bread back in the days of poverty and strife) hooked up to a half-inch Milwaukee with a lot of torque. I used to think my grind was a bit fine, but the husks were always in good shape and the conversion was good.

I think I'll do two more identical batches, one with the pre-ground malt and the other with my own grind, and compare...

And, of course, I'll crack one before even heating the water!

Oh, and another thing... I've just ordered a pound of that PH stabilizer... It's supposed to fix your mash at 5.2 no matter what. Sounds too good to be true. Anyone had experience with this stuff? Will it give you cancer, or will you be reborn with three heads or something? Or is it just another miraculous wonder from the world of chemistry?

Thanks to all, jp

Hey jp,

First, I agree with the Baron... too course a crush and you lose efficiency... too fine and you get a very cloudy beer...

Second, how much wort did you collect this time??? Just FYI if you add 1/2 gallon of water to 4.5 gallons of 1.050 wort you would end up with 5 gallons of wort at about 1.045... if the crush was similar, then this may be a culprit in this case... (ProMash has a dilution calculator to make dilutions with either water or wort easier to understand... did I mention how much I love ProMash??? )

You should still end up around 4% ABV with this beer... so you'll just have to drink them faster to make up for it LOL... and by all means make sure you open a beer before you mash, what were you thinking??? LOL

ProMash is my favorite bit of software at this time... and about the best $25 I've spent on brewing in a while too... you can find it at http://www.promash.com/

Oh, and unless I misunderstand (and I just might LOL)... Mash temp has to do with the overall fermentability of the wort... OG is due more to the efficiency of your setup, grain crush, sparging setup,etc... but FG is based on a combination of mash temps, pH,time and thickness of the mash and attenuation of the yeast you are using, no??? i.e., OG is overall amount of sugars extracted, but the type of sugars extracted determine the potential for a lower or higher FG. (If I've botched this concept, someone please let me know... I'm still learning some of this stuff myself)

That should be clear as mud now, no???

mikey

Good point about the temperature and types of sugars, Mikey, and I did collect a bit more wort the second time around... So, all things considered, my efficiency with both batches may have been similar, if not all that great.

It will be interesting to compare the terminal gravities of these two beers, given the temperature difference of the mash... although I'll be comparing apples and oranges, er, I mean, barley and oats, there too. The value of changing only one variable at a time remains paramount-

I will, of course, be investing in this Pro-mash thing, and even though this forum is taxing my computer skills to the hilt, I'm resigned to modernizing my humble system. Damn, whatever happened to leaving a bunch of grain in the bird-bath?

thanks again for the feedback,
jp