specific gravity/brix level - Home Brew Forums

 Home Brew Forums > specific gravity/brix level

05-06-2013, 01:21 PM   #1
winewitted
Recipes

May 2013
Posts: 15

Hi I am making a pineapple wine that calls for 3lbs of pineapple and,about 4 cups/ 576g of sugar. I used about 2.75lbs pineapple but when I took the reading I was at about 1.070 and I'm supposed to be at 1.090. My question is since the pineapple has sugar in it how do we get that into the equation?

05-06-2013, 08:12 PM   #2
WilliamSlayer
Recipes

Aug 2012
Glen Burnie, Maryland
Posts: 1,613
Liked 157 Times on 141 Posts

What is the size of your batch. 3 gallons? 1 gallon?

If one gallon than to go from 1.070 to 1.090 you only need 1/2 lb of sugar. Most sugar will give you about 40 gravity points per pound.

05-08-2013, 05:00 PM   #3
winewitted
Recipes

May 2013
Posts: 15

Quote:
 Originally Posted by WilliamSlayer What is the size of your batch. 3 gallons? 1 gallon? If one gallon than to go from 1.070 to 1.090 you only need 1/2 lb of sugar. Most sugar will give you about 40 gravity points per pound.
its a one gallon batch. I added 1/5kg of sugar and topped off the water to about one gallon and its correct now.

05-09-2013, 09:49 AM   #4
WilliamSlayer
Recipes

Aug 2012
Glen Burnie, Maryland
Posts: 1,613
Liked 157 Times on 141 Posts

I've read that the gravity of a wine will RISE as the sugars dissolve out of tthe solid fruit. Good rule of thumb is to not add any extra sugar till you have taken a gravity reading AFTER you have removed the fruit pulp. Hope it turns out tasty! :-)

05-09-2013, 01:27 PM   #5
Yooper
Ale's What Cures You!

Recipes

Jun 2006
UP of Michigan, Winter Texan
Posts: 69,738
Liked 8015 Times on 5601 Posts

Quote:
 Originally Posted by WilliamSlayer I've read that the gravity of a wine will RISE as the sugars dissolve out of tthe solid fruit. Good rule of thumb is to not add any extra sugar till you have taken a gravity reading AFTER you have removed the fruit pulp. Hope it turns out tasty! :-)
Well, once it starts to ferment then the OG would be incorrect even if you get more sugars out of the fruit.

It's true that the fruit will give up a bit more fermentable sugar as it breaks up, but not usually a meaningful amount unless the fruit is rock hard when you start. "Mushy" fruit can be smashed up a bit and the OG reading at that time is pretty close to the actual amount of sugars that will ferment.

Edited for clarity- When I mix up the must, I always wait 24 hours before adding yeast. So the must is made up, the fruit smooshed up in the bag (or whatever I've got in there), and pectic enzyme added. The OG is taken the next day before adding yeast. It may not be 100% of the fermentable sugars, but it really seems to be "close enough" as most fruits don't have all that much sugar left in them to make a big difference.
__________________
Broken Leg Brewery
Giving beer a leg to stand on since 2006

05-09-2013, 02:56 PM   #6
WilliamSlayer
Recipes

Aug 2012
Glen Burnie, Maryland
Posts: 1,613
Liked 157 Times on 141 Posts

Good point Yooper, taking a gravity reading as you add the fruit, and then again after 24hrs will probally be a bit different BUT that 24 hrs after the fermentation starts (yeast pitch) will be very different gravity.