What happened to my brew?

[thetick]

I’m relatively new to home brewing and decided to play around with a SMASH brew to experiment and learn. I’ve never created a recipe before, but I had leftover ingredients and an online recipe builder so I gave it a shot. Here is the recipe (1 gallon brew):

1.75 gal Water
1 lb Golden Light DME

30 Minute Boil (I ran out of propane in the middle of the boil, so it ended up being more like 40 minutes after getting everything back up to temp.)
.25 oz Cluster @ 20
.25 oz Cluster @ 0
US-05 Yeast

According to brewers friend, I should have gotten an OG of 1.045. Mine was a measly 1.030. Really curious as to whether you all have any thoughts as to what happened?

Final note: the boil-off calculation may have been a bit off as I got a little more than a gallon (< 1.25 gal), but I didn’t think that was enough to cause the large OG difference — was it?

Thanks!

 

[BrewnWKopperKat]

It looks like you started with too much water for a 30 min boil.

1 lb DME (45 PPG) in 1.5 gal water will create a wort that's approximately OG 30.

1 lb DME in 1.25 gal water will create a wort that's approximately OG 36.

 

[mac_1103]

According to brewers friend, I should have gotten an OG of 1.045. Mine was a measly 1.030. Really curious as to whether you all have any thoughts as to what happened?

How did you measure the gravity and when? Did you cool the sample and/or adjust for temperature?

1.045 is correct for 1 pound of Briess Golden Light DME in 1 gallon of water. But every little bit of extract that didn't make it into the kettle and every little bit of extra water will lower the gravity.

 

[thetick]

It looks like you started with too much water for a 30 min boil.

1 lb DME (45 PPG) in 1.5 gal water will create a wort that's approximately OG 30.

1 lb DME in 1.25 gal water will create a wort that's approximately OG 36.

Thanks! I’m guessing it did have something to do with the lack of boil-off. I didn’t have 1.5 gallons — it fit easily in a 1.25 gallon fermenter and I had head space. It’s possible I didn’t measure the DME going in correctly, I guess. (But I use a digital scale and it’s never happened before.)

Does age of DME affect OG? It’s been sitting around for a few months.

 

[thetick]

How did you measure the gravity and when? Did you cool the sample and/or adjust for temperature?

1.045 is correct for 1 pound of Briess Golden Light DME in 1 gallon of water. But every little bit of extract that didn't make it into the kettle and every little bit of extra water will lower the gravity.

Measured the gravity with a hydrometer after cooling.

 

[BrewnWKopperKat]

Does age of DME affect OG? It’s been sitting around for a few months.

Age does not impact OG.

It’s possible I didn’t measure the DME going in correctly, I guess. (But I use a digital scale and it’s never happened before.)

OK - I was assuming that you used a 1 lb bag of DME.

OG 30 in 1 gal (16 cups) of water requires about 11 oz of DME.

If you poured the DME from a larger bag into a bowl, was the scale (with the bowl on it) zeroed before adding the DME?

 

[thetick]

Age does not impact OG.

OG 30 in 1 gal (16 cups) of water requires about 11 oz of DME.

If you poured the DME from a larger bag into a bowl, was the scale (with the bowl on it) zeroed before adding the DME?

Based on that I think my boil off volume was way off. I did run out of propane in the during the boil and arbitrarily added another 10 minutes to compensate. Looks like I guessed wrong! I’m also guessing that the 1.25 gallon bit mouth bubbler fermentor I used holds more than advertised. The next time it’s empty, I’ll have to measure it.

View attachment 817982

This is a great chart! Is there an underlying formula you used?

Thanks again!

 

[mac_1103]

The little big mouth bubbler holds 1.4 gallons.

 

[thetick]

The little big mouth bubbler holds 1.4 gallons.

That explains it! Thanks!

 

[BrewnWKopperKat]

This is a great chart! Is there an underlying formula you used?

After populating row 2 and column b, put =+C$2/$B3*45 in C3 & copy it to the other cells. (45 is PPG for DME).

I added conditional formatting to highlight SGs between 25 and 35.

 

[CascadesBrewer]

That explains it! Thanks!

Do you have the glass versions of the LBMB? The PET one has some marking on it up to the 1 gallon level. I have both and they can easily hold 1.5 or more liquid. For reference, here are two pictures with a glass LBMB filled to 1 gallon and to 1.5 gallon. The 1 gallon line is about half way between the middle and top "rib". The 1.5 gallon line is right where the rounded side meets the straight top.

 

[BrewnWKopperKat]

The non-spigot'ed little BMBs appear to be the same size.

I typically do not fill them above 1.25 gal which is roughly the top rib (green arrow).