Fruit and measuring O.G or Start Gravity

[Bubbles2]

So I am about to make a version of Jack Kellers Peach, using 1lb Banana and 5lb Peaches
I am thinking about O.G of 1090-1095 Do not want it too hot or strong.

So I add my peaches Froze defrost 3 times (masticate), banana (simmered for 35min skimmed,strained)
Put in nylon bag.... adding sugar and thinking should I wait a couple days with a lb of sugar atop the fruit to then measure O.G? and come check it after it has had time to expel any sugars?
OR just mash it up, stir and add sugar to desired O.G?

I ask that because I am wondering about topping off, adding campden, (don't want it start fermenting with wild yeast) some sugar and how long should I wait to come back or commence to add sugar to get to my S.G ?
And by waiting to pitch how long will that stay sterile?

Thoughts?

 

[bernardsmith]

You could see how much sugar you have in your peaches by using a refractometer. That is how those who make wine from grapes determine when to harvest the fruit. Bananas are more of a problem because initially with banana all you have are the complex carbs but you might add some amylase to the fruit and see how much syrup you get and again measure the sugar content optically. That said, I would assume that peaches typically contain about 45 - 50 points of sugar in every gallon of juice they expel but I have no idea about banana but you could check a nutritional guide for how many calories are in an average banana and how much of those are from sugar and you can assume that you can access most if not all those sugars - then knowing the total volume of your must will give you an idea of how many pounds of sugar you may want to add to every gallon to hit 1.090

 

[Seamonkey84]

I Follow these instructions for a wine making liquor, that way you have a much closer idea of the gravity including the fruit juice. Scroll down a bit, pass the recipes.
https://eckraus.com/making-strawberry-wine-recipes/

 

[Bubbles2]

Thanks SeaMonkey, as suspected except I did not think to use the Pectin Enzyme to further break it down faster.

 

[Bubbles2]

You could see how much sugar you have in your peaches by using a refractometer. That is how those who make wine from grapes determine when to harvest the fruit. Bananas are more of a problem because initially with banana all you have are the complex carbs but you might add some amylase to the fruit and see how much syrup you get and again measure the sugar content optically. That said, I would assume that peaches typically contain about 45 - 50 points of sugar in every gallon of juice they expel but I have no idea about banana but you could check a nutritional guide for how many calories are in an average banana and how much of those are from sugar and you can assume that you can access most if not all those sugars - then knowing the total volume of your must will give you an idea of how many pounds of sugar you may want to add to every gallon to hit 1.090

Thanks for the reply, however I do not have a refactor M so I asked what steps you all take. SeaMonkeys link was what I was asking as in steps.

 

[JimRausch]

Mix up your batch, with pectinase or not, with Camden or not, and take an SG reading just before you pitch your yeast. If your SG is not as high as you would like it, add some sugar or honey and measure again. Ouila, OG.

 

[Bubbles2]

Mix up your batch, with pectinase or not, with Camden or not, and take an SG reading just before you pitch your yeast. If your SG is not as high as you would like it, add some sugar or honey and measure again. Ouila, OG.

So the recipe was strange where it wanted me to pitch half my sugar before and then the other half after ferment and I was thinking how will I ever know my SG? Hence the ? It is already in the Primary for a few days now start at 1095 move to primary at 1010

 

[JimRausch]

So the recipe was strange where it wanted me to pitch half my sugar before and then the other half after ferment and I was thinking how will I ever know my SG?

Hmmm. That is odd. But I do trust Jack Keller. Use his recipes all the time, although admittedly, I change them up.

 

[beermanpete]

Sugar is 100 percent fermentable and quite predictable. This allows the calculation of, and prediction of, its contribution to OG easy and reliable. IIRC, sugar is 42 ppg, meaning that each pound yields a SG of 1.042 in one gallon of water. If you add 2 pounds of sugar to 5 gallons of must or wine you will add 16.8 gravity points to the OG.

(42 x lbs. Sugar) / volume of wine = OG contribution

 

[bernardsmith]

Totally agree with beermanpete. To determine the total "starting" SG of a must when you have staggered the addition of sugars requires simple arithmetic. If you know the total volume and you know the total amount of added sugar (and you know the average gravity of each pound of sugar in light of the total volume of liquid then by calculation you can determine the SG (close enough, at any rate to ignore the need to take a measurement): you divide the total SG of the sugar by the total volume of US gallons of the liquid

 

[Bubbles2]

Sugar is 100 percent fermentable and quite predictable. This allows the calculation of, and prediction of, its contribution to OG easy and reliable. IIRC, sugar is 42 ppg, meaning that each pound yields a SG of 1.042 in one gallon of water. If you add 2 pounds of sugar to 5 gallons of must or wine you will add 16.8 gravity points to the OG.

(42 x lbs. Sugar) / volume of wine = OG contribution

Math is easy when you have the formula.....

 

[bernardsmith]

But as a Scot I would argue that math is about theory and arithmetic is simply about numbers and here the issue is really only about numbers and not theory.