How does yeast starter affect OG?

[todd49401]

Hey everyone, about a month ago I brewed an NB Imperial Stout with an OG of 1.090 (5 gal). After I took the OG, I added a yeast starter that had 16 oz. water and 1/2 cup LDME and 8 oz. maltodextrin. I used Wyeast smack pack Scottish Ale.

What will be the increase in gravity given the 1/2 cup LDME and 8 oz. maltodextrin- .008?

I also added the yeast nutrient powder. Is this starter good enough to eat all the sugar in a big beer? The starter was made 24 hours before adding to the 5 gallons.

What should my target FG be? 1.030?

I'm going to be transferring my stout to the secondary so I need to know so I can measure my FG and determine ABV.

Thanks

Note: I posted this in the yeast forum too...

 

[JoePro]

Note: I posted this in the yeast forum too...

I take it my answer wasn't satisfactory?

 

[Malintent]

Your FG should be closer to 20.. .24 hours for your yeast starter prolly was not enough to get maximum attenuation, though. The added ABV from the starter will most likely be negligible (less than 0.1%)

 

[dcp27]

there should be no increase in OG from a starter, in fact, it'll minimally decrease unless you decanted it, in which case theres no change.

that was too small of a starter for that size beer. check mr malty for correct pitching rates

without knowing the recipe, its hard to say what the fg would be, but 1.03 is probably close.

edit: just realized you made waaay too high of a gravity of a starter. it should be in the 1.03-1.04 range. you likely over-stressed and killed most of your yeast and will be getting tons of off flavors in this as well as a higher fg, id get some new yeast asap.
i highly recommend reading these two articles
http://www.mrmalty.com/starter_faq.php
http://www.mrmalty.com/pitching.php

 

[todd49401]

I take it my answer wasn't satisfactory?

Sorry, I actually posted this before your answer...

 

[todd49401]

I just checked the FG on the beer and it was at 1.032. That's too high IMO. Not sure what to do...it's been in the primary for a month. Should I go ahead and pitch more yeast into the secondary and hope it drops more?

 

[JoePro]

I just checked the FG on the beer and it was at 1.032. That's too high IMO. Not sure what to do...it's been in the primary for a month. Should I go ahead and pitch more yeast into the secondary and hope it drops more?

For a porter that was 1.090 to finish about 1.030 is completely normal. Was your recipe all malt or did you use sugar adjuncts?

 

[todd49401]

Recipe
0.5 lbs Simpsons Roasted Barley
0.5 lbs Simpsons Black Malt
0.5 lbs Simpsons Chocolate
12 lbs. dark malt syrup 60 min
1.75 oz Summit 60 min
2 oz Cascade at flame out

When I transferred to the secondary it tasted pretty good- didn't seem too sweet...was hoping for a little under 1.030 though.

 

[JoePro]

Just let it condition. It will probably drop a few more points over time (especially because you'll be aging it for a few months)