Trying my first 'experiment' wine, advice on SG timing?

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Xiola

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So I decided to try a mango wine experiment (meaning, first non-kit) after reading a few recipes . The one thing I am not quite grasping is, if I do the 24 hour 'wait' for a camden tablet to do its thing before I add yeast (and I assume yeast nutrients?) when do I take SG? Today? Tomorrow before yeast?

Apologies if this seems basic, no book I have consulted really explains this in finer detail (for my brain anyway, ha)

Thanks for any thoughts here, just hoping to get a good idea of final alcohol content.
 

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I predict it won't change much. (That is not the reason for waiting.) But...., why not take it two times, and find out for yourself for all time?!
I was going to both, but figured I would just wait until tomorrow. I didn't know if there was a 'formal' answer on what was 'the right way' ;)

Maybe I am just expecting more 'supposed to be this way' black and white than I am finding and overthinking things. ha.
 
Working with real fruit or fruit juice? Makes a difference. Real fruit may not release all the sugar immediately - that's why you need to mash it, crush it, whatever to get it to break down as much as possible before you start the ferment. Some folks run their fruit through steamers, or food processors (Preferably slow turning ones not the blender-like ones) In any case you can't take too many pre-ferment SG readings. Campden tabs/K-meta before ferment is just to keep bacteria or wild yeasts from gaining a foothold before your yeast can do it's thing.
 
Working with real fruit or fruit juice? Makes a difference. Real fruit may not release all the sugar immediately - that's why you need to mash it, crush it, whatever to get it to break down as much as possible before you start the ferment. Some folks run their fruit through steamers, or food processors (Preferably slow turning ones not the blender-like ones) In any case you can't take too many pre-ferment SG readings. Campden tabs/K-meta before ferment is just to keep bacteria or wild yeasts from gaining a foothold before your yeast can do it's thing.

I used (previously frozen) Mango that I ran through with a food processor. I made essentially a puree as I read that Mango will break down so much in the straining bag that it was not really worth it (not much pulp comes back out in the bag).

Given how thick it is I expect to lose a significant portion of it as sediment, and wondered if this will affect my SG. Which is why I also decided to wait until tomorrow to take it (tho not sure if that actually will make a big impact given the puree wont break down much in 24 hours). Not sure if that was good or bad, so wanted to check with the people who have many more batches under their belt. :D
 
Yeah those thick musts are hard to measure. You have to wait a little for it so breakdown some but not too long that it starts to spoil. (Lost one batch that way, the "odd" smell was definitely NOT fermentation.)
In any case make sure it's dosed properly with K-Meta/campden tablet and perhaps a little heavier on that treatment to give you an extra day for things to start to break down. I've had to play games with my peach batches because I could 'place' the hydrometer at any level I wanted. Found out that after about 2 days I could put my sample in a large testing tube and twist quickly back and forth until it settled down. Then I'd repeat that a couple of times then push below the settled point and repeat and watch it rise until it stopped. A royal pain to do but I think you can get close enough on your reading to know if it's a high or low ABV batch. Getting really accurate is tough to do. Almost needed a vibrator to get the hydrometer to settle into a good / reliable reading. I might be off with it looking like 1.090 (13.13% ABV) when it's really 1.085 (12.47% ABV) or 1.095 (13.78% ABV) but in any case that gets me in the ball park to know if I've got enough sugar to get it in the ballpark.
And yes plan on losing as much as 1/3 at the extreme to solids. BUT when you do rack out of the bucket, save that last portion and put it in a quart or 1/2 container in the fridge for a day or two and you will be surprise how much it will settle out in the cold. from a quart you might get a full pint back. Just start well above your target volume.
 
Hi Xiola, Strikes me your question is really a good one. If rather than use an hydrometer you use a refractometer to take a reading of the sugar content of the mangoes you would not need all the sugars to be released into the must to be able to know that your fruit had the equivalent of say 1 lb of sugar in a gallon or as much as 1.5 lbs. But you might need to wait to find out the actual SG if you were adding water and the juice from the fruit was still slowly being extracted so the total volume of liquid (and sugar) in the must was not yet set.
With an hydrometer I always thought that the density of the liquid was what this was measuring so it will measure dissolved sugars, but is the density of the water affected when the water contains particles of fruit and fibers that are not dissolved. My sense is that that should NOT affect the buoyancy of the hydrometer. But I am not certain...
 
Hi Xiola, Strikes me your question is really a good one. If rather than use an hydrometer you use a refractometer to take a reading of the sugar content of the mangoes you would not need all the sugars to be released into the must to be able to know that your fruit had the equivalent of say 1 lb of sugar in a gallon or as much as 1.5 lbs. But you might need to wait to find out the actual SG if you were adding water and the juice from the fruit was still slowly being extracted so the total volume of liquid (and sugar) in the must was not yet set.
With an hydrometer I always thought that the density of the liquid was what this was measuring so it will measure dissolved sugars, but is the density of the water affected when the water contains particles of fruit and fibers that are not dissolved. My sense is that that should NOT affect the buoyancy of the hydrometer. But I am not certain...

Suspended solids do affect the measured SG. The good news is that, if they are suspended, their density is probably pretty similar to the rest of the solution, so I wouldn't worry about it. (It is possible, in extreme circumstances, to have a very dense solution due to suspended solids; this occurs, for example, in drilling oil wells, but this is not what we are talking about here.)
 
Thanks Sour_Grapes. This is good to know. I always simply assumed that the density as measured by an hydrometer was dependent on what was dissolved in the water and not what was simply in the water but was never 100 percent certain.
 
Thanks Sour_Grapes. This is good to know. I always simply assumed that the density as measured by an hydrometer was dependent on what was dissolved in the water and not what was simply in the water but was never 100 percent certain.

I must admit that, even though I am a physicist, I also got tripped up by believing the same as you. (Someone with more practical knowledge clued me in. You know who you are!) But, if you think about what a hydrometer actually does, it becomes more clear. You put a weight in, and it raises the level of the liquid around it to counterbalance. It isn't so different from a see-saw, really. Does a see-saw care about whether the weight on the other side is one fat kid or two skinny kids? The only thing that matters is if the weight on the other side must be raised up or not. (Strained analogy, but roll with it...:i )
 
Another good reason to use a fermentation bag to TRY and hold out some of those solids so you have a more measurable 'liquid' Easier said that done with some fruits - Peaches are a real tough one for me. Usually I end up waiting 2 days after crushing and adding some of the sugar, to get a decent reading. But wait too long and it can spoil on you even with k-meta - been there done that and had to toss a batch.
 
I must admit that, even though I am a physicist, I also got tripped up by believing the same as you. (Someone with more practical knowledge clued me in. You know who you are!) But, if you think about what a hydrometer actually does, it becomes more clear. You put a weight in, and it raises the level of the liquid around it to counterbalance. It isn't so different from a see-saw, really. Does a see-saw care about whether the weight on the other side is one fat kid or two skinny kids? The only thing that matters is if the weight on the other side must be raised up or not. (Strained analogy, but roll with it...:i )

I toss the thoughts around as well, and am certainly no physicist, having only an engineering background, and very little retained from college. As I understand it, the buoyancy of the liquid is what determines how high/low the hydrometer floats, and the buoyancy is directly related to the amount of dissolved solids in the solution. The more dissolved solids, the more buoyancy, sugar being the predominant dissolved solid in the solution. It seems to my simple mind, that unless the particulates floating in the must (which are not dissolved solids) affect the ability of the hydrometer to float freely, they are immaterial. Nonetheless, I always strain out the big stuff to take a reading, just in case.....
 
My background is social science but if Sour_Grapes has experimental data in support of his claim then I will accept it BUT if I were to stretch his analogy - and plump an ocean going liner into a dock after measuring the density of the water between the dock and the liner, the gravity of that water is not going to rise by 1/1000 of 1/1000 of 1 point with the added ship in the dock so I cannot see why added fruit that was not dissolved in the water to increase the density of the liquid will show up as increased density... But if it does then it does... but I cannot see how it does
 
Consider a slurry of clay. The particles are not dissolved, they are suspended. The average density of the fluid can be quite high (SG>4). Take a look at these pages:

https://en.wikipedia.org/wiki/Baryte
https://en.wikipedia.org/wiki/Drilling_fluid

So, I read those pages, well briefly scanned them, since I worked in the oil & gas industry out at the wells in a previous life (I was an open-hole well logger, with the big company that did that in the 80's). I wish I had read somewhere that viscosity doesn't impact density, that's really the argument you are making, isn't it?? Common Sense (which is often wrong sense, for sure) says that given 2 fluids, the more viscous one should read more dense. Taking it to two extremes, water and very pulpy must (like peach often produces), with the same sugar content. Maybe I am misunderstanding, which is often possible with just words to read.
 
So, I read those pages, well briefly scanned them, since I worked in the oil & gas industry out at the wells in a previous life (I was an open-hole well logger, with the big company that did that in the 80's). I wish I had read somewhere that viscosity doesn't impact density, that's really the argument you are making, isn't it?? Common Sense (which is often wrong sense, for sure) says that given 2 fluids, the more viscous one should read more dense. Taking it to two extremes, water and very pulpy must (like peach often produces), with the same sugar content. Maybe I am misunderstanding, which is often possible with just words to read.

No, no, viscosity and density are not related. Mineral oil, coconut oil, (or if you want to push the point, paraffin and butter) are far more viscous than water, and yet are less dense.
 
My background is social science but if Sour_Grapes has experimental data in support of his claim then I will accept it BUT if I were to stretch his analogy - and plump an ocean going liner into a dock after measuring the density of the water between the dock and the liner, the gravity of that water is not going to rise by 1/1000 of 1/1000 of 1 point with the added ship in the dock so I cannot see why added fruit that was not dissolved in the water to increase the density of the liquid will show up as increased density... But if it does then it does... but I cannot see how it does

The difference is that the ship is floating. Yes, when you put your hydrometer in, in order for the hydrometer to sink in, it has to raise the ocean liner by a small amount. But (if there were no ocean liner there), the hydrometer would instead have to raise the water that the ocean liner displaced by the same amount. Not coincidentally, that chunk of water has a mass that is identical to the mass of the ocean liner.
 

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