Base SG of Welch's 100% juices???

[Intheswamp]

I'm curious about the SG of pure Welch's 100% juices, especially the White Grape & Peach version. has anybody got any info on this? Thanks. Ed

 

[bucketnative]

Welch's should give you the total sugars on their nutritional label. You can rough it from there:
Amended on 9/18/2019 - forgot a factor of 100!
100 * [X g / (8 fl.oz. * 29.6 ml/fl.oz.)] = Bx (approx.)

It'll be off a bit, because this is going by volume rather than mass of solution. But, it'll get you within a few %.

 

[Intheswamp]

Thanks for the formula, bucketnative!!!

Ok, so if the juice shows 31g per 8oz of juice it would be:

31/(8*(29.6/8))=1.047

Am I close? Sound reasonable?

I'm just wanting to tinker with some on-line calculators and the juice. Will give me an idea of how much (or little) water and sugar I'll need.

Thanks again!

 

[Blacksmith1]

That's probably very close. The welches simply refreshing peach mango juice is 1.042. Tested with hydrometer.
I would think most of the juices would be around that. From .040 to .060. This is just a guess.

 

[Blacksmith1]

Double post...

 

[RPh_Guy]

FYI
The FDA allows a 20% error margin on nutrition labels. S.g. will vary from lot to lot.

Also, keep in mind a significant number of gravity points in cider are from non-sugars (malic acid in particular), so calculation isn't much better than guessing.
I'd agree with @Blacksmith1, s.g. should generally be between 1.040 and 1.060.

 

[Intheswamp]

Thanks everybody. Looks like I just need to stick a hydrometer into it.

I ran the below sugar contents in a spreadsheet, though, and came up with the SGs below.

X g (sugar) / [8 fl.oz. * 29.6 ml/fl.oz.] = Bx (approx.)

sugar grams / oz of juice / SG / Welch Brands

30 8 1.0135
31 8 1.0473 White Grape & Peach =31/(8*29.6/8)
32 8 1.0811
33 8 1.1149
34 8 1.1486
35 8 1.1824 Black Cherry & Concord Grape
36 8 1.2162 Concord Grape, White Grape, Red Grape
38 8 1.2838 Mango =38/(8*29.6/8)

The formula seems to work for the White Grape & Peach, but other sugar contents seem to throw the SGs way out of range. Weird. I've about bent my mind into a pretzel trying to figure that out. I'm sure it's something simple but my wooden head is struggling to figure it out.

If I go to Fermcalc and enter in 8oz volume and 31 grams of sugar (White Grape & Peach) I get 1.0466 which is pretty close (horseshoes) to the calculation above. This is using the "Chaptalization and Dilution Calculator". But, if I enter in 8oz volume and 36 grams (Mango) I get a more realistic SG of 1.0535 which is far lower than what the formula comes up with.

Like I said, I'll just check it with a hydrometer when I get ready to make up a batch but the math/spreadsheet/Fermcalc contradiction is about to blow up my brain. I'm doing something stoopid I'm sure, but I sure can't figure it out. Anybody want to give me a short algebra(?) lesson?

 

[bucketnative]

Like I said, I'll just check it with a hydrometer when I get ready to make up a batch but the math/spreadsheet/Fermcalc contradiction is about to blow up my brain. I'm doing something stoopid I'm sure, but I sure can't figure it out. Anybody want to give me a short algebra(?) lesson?

See my edit to the formula I gave above... I left out a factor of 100! Sorry if that got you down the wrong path. You also had an extra "8" in the denominator.

So according to Welch's White PEach Grape label... 31 g sucrose / 8 fl.oz.

Bx = 100 * [31 g / (8 fl.oz. * 29.6 ml / fl.oz.)] = 13.1 Bx - Then you can use a calculator to convert Bx to SG: https://www.brewersfriend.com/brix-converter/

For White Peach Grape: 13.1 Bx = 1.053 SG

The 13.1 Bx number seems like it is in the ballpark if you look at the federal definitions of standard Brix for fruit juices (see slipskin grapes and peach) - https://www.law.cornell.edu/cfr/text/19/151.91. One must also realize that the juice is a blend with pear and apple juices as well, so 13.1 is probably OK. Brix technically only accounts for sucrose... there are other carbohydrates in there that can affect the SG (Note on the label that the total carbs is 33 g / 8 fl.oz.).

Look at your black cherry and concord grape juice: Bx = 100 * [35 / (8 * 29.6)] = 14.8 Bx, which is converted to a SG of 1.060.

 

[bucketnative]

That's probably very close. The welches simply refreshing peach mango juice is 1.042. Tested with hydrometer.
I would think most of the juices would be around that. From .040 to .060. This is just a guess.

Well, your measurement is right on with the calculator: 100*[25/(8*29.6)] = 10.56 Bx, which converted to a SG 1.0425

I would also think that even though the federal law allows for 20 % variation in label claims for sugars, a major juice manufacturer would have much tighter tolerances on their manufacturing process than that. Especially because most of their juices are from concentrate and you can easily measure the sugar content. Their goal is to put out a homogeneous product year to year.

 

[Intheswamp]

Thanks ya'll!!! My head was about to explode!!!!

@bucketnative , I can understand a company such as Welch's having a desire to produce a consistent product. With the calculations it might be interesting to see how close (or far) from the stated sugar content the different bottlers stay to the stated amounts. Calculate from the ingredients label and then test with a hydrometer...see how close the figures are to each other.

 

[RPh_Guy]

I would also think that even though the federal law allows for 20 % variation in label claims for sugars, a major juice manufacturer would have much tighter tolerances on their manufacturing process than that. Especially because most of their juices are from concentrate and you can easily measure the sugar content. Their goal is to put out a homogeneous product year to year.

I've measured different lots of juice, and indeed the gravities do vary widely.

We can put this speculation to rest.

 

[Intheswamp]