Measuring SG after Fermentation Begins

[arcticsid]

Failed to measure SG before adding the yeast, just started my first batch about 50 hrs ago, it did not begin to "ferment" until hour 40. So..I just bought a hydrometer. Is it too late for me to take a SG reading now, or should I wait till the secondary fermentation.
Thanks
ArcticSid

 

[Luc]

What king of fruit /juice are you using.

Depending on the kind of fruit maybe we can come up with an average on SG for that kind of fruit.

Luc

 

[arcticsid]

refer to "First batch Concerns" by me. I started with (4) frozen concentrate Apple/Raspberry, and (1) frozen concentrate white Grape juice, reconstituted as required. I boiled one gallon of water, added one quart of wild raspberries and 1 cup wild low bush cranberries(I live in Fairbanks Alaska, U.S.) I allowed this to seep until it reached about 70 degrees/F Then I smashed the berries and added it to the above. Thanks for your help Luc, appreciate it.

 

[Luc]

Ok here we go:

1 quart raspberries is about a liter.
The Sg of raspberries is about 1040.
That should give you about 84 gram sugar per liter.
You added 1 quart berries. Let us say they contain about
75 procent extractable material. So 75% of 84 gram would be
about 65 gram sugar

1 cup cranberries is about .233 liter
Cranberries contain about the same sugar level
so that would be 84 gram per liter.
For .223 liter that would be about 18 gram
again at 75% = 18 *.75 = 13.5 gram sugar.

So the total of the added sugar in fruit would be
65 + 13 = let us say 80 gram rounded up for safety.
Nothing to be worries about

These figures assume that the SG would be around 1040.

Now I think the cans of concentrate should
list how much sugar would be in it.
Otherwise I would appreciate it when someone
chimes in with figures about concentrates......

But this should give you enough handles to work with.

You can however accurately measure how high the SG is at THIS
moment.
Take a cup of must and boil that for let's say 10 minutes.
Then add enough water to fill it up again to a cup.
The alcohol and co2 would be evaporated and you should have a pure
must again which you can take a reading from.
But keep in mind that some sugar is already consumed so you
will not have an initial SG but the actual SG at this moment.

Luc