Prize for most priceless question

[plato25]

Hi

I bought a wine refractometer from a seller (no name to protect the guilty/innocent) on Amazon.

I calibrated it with distilled water. The tested it on two commercial Bordeaux wines of excellent quality. One 13.5% ABV the other 14%. I readings of between 5%- 7%. Clearly faulty.

So issued a return. Then followed questions re testing. Then the most priceless question of all:
“Thanks for your response.
Please confirm what kind of wine the Bordeaux wines you have tested. Are they grape wine?”

Is Bordeaux wine made from grapes? Is the a pope Catholic? Premier Grande Cru wines at about £50 a bottle!

I’ll have to ask the wine merchant to check with the grower.

Item being returned as being sold by an *****.

 

[cmason1957]

Before you return it. By taking one reading after fermentation is completed, you cannot determine the ABV of a wine. And, once alcohol is present, like in a fermented wine, the refractometer cannot give you an accurate measurement of the Potential Alcohol that could be produced, if fermented.

Refractometers are calibrated to give you an accurate measurement of the amount of sugar in a sample by depending on how much the light bends (the refraction angle). Once alcohol is present, that refraction angle is skewed. If you know the starting amount of sugar, then you can correct and determine the current level of sugar in your sample.

 

[plato25]

That makes sense but that isn’t how it is sold. I haven’t checked it on homemade wine.

 

[ibglowin]

Refractomers for winemaking read sugar content or Brix in grape must. Not alcohol content.

 

[salcoco]

there are correction calculations on the Internet. start with Northern Brewer

 

[plato25]

Lots of replies to this question, mostly interesting. The msg was really about the question asking are Bordeaux wines made from grapes. An astonishing question IMHO.

 

[BernardSmith]

Lots of replies to this question, mostly interesting. The msg was really about the question asking are Bordeaux wines made from grapes. An astonishing question IMHO.

True...Daft question, I agree... but we live in daft times so, for example, Vintner's Best fruit juices contain far more sugar and grape juice than the fruit named on the jug. And yes, I will name the guilty to protect the innocent.

 

[plato25]

Hi all

I’m thinking of building a wine pump/filter setup. I know that the AIO pump is the best option but it’s not available here in the UK and is beyond my budget even without shipping costs.

I have a couple of 5 gallon carboys and won’t “enjoy’ moving them around, Hence the need for a pump.

I start with racked and cleared wine. I want to transfer it from the donor carboy (D) to a receiving carboy (R) via a filter.

As wine is drawn from D obviously air will enter the system. Is there any way to connect a CO2 cartridge to D to replace the air that would otherwise be drawn into D? [I need to degas the wine in D before transfer to R or the filter].

My questions are:

1. Best way to degas the wine in D?
2. Viability of using a CO2 capsule to replace air in D?
3. Recommendations for a suitable filter?
4. Recommendations for a suitable vacuum pump?
5. Any snags/pitfalls to be aware of?

Sorry if this sounds convoluted be it is essentially simple (!!):
D(air free)….. Filter…..R …. Vacuum pump. At this point I would bottle as usual.

Thanks in advance for help/replies

 

[Rice_Guy]

@plato25
* degassing, what I do is a cork with a check valve. The definition of good enough is that it can hold a -5 inch Hg/ 15 Kpa vacuum for thirty minutes. Many home wines have more CO2 than this and you can’t taste it, ,, but I vacuum cork.
Transferring with vacuum also will degas. ,,, I intentionally try to hold CO2 in the wine till I am ready to bottle.
* yes you could push with CO2, this isn’t part of the specification of normal carboys. I would NEVER use high pressure on home grade glass. Commercial wine will flush the tubes and filter with nitrogen and have a dissolved oxygen specification and run the filler with nitrogen. ,,, home wine will add metabisulphite, it is hard to keep oxygen out with 20 liters.
* for lots of wine you want a commercial HVAC vacuum pump (pulls -22 or -24 inches Hg) wired for your power. I mainly do gravity assisted so I am using inexpensive (20£) 12V DC which pulls -22 inch Hg.
* you didn’t say it but use a vacuum gague, always have a liquid trap before the pump
* filter? For what purpose? Sterile is called absolute filtration (0.45 micron) and is used commercially. A polishing filter will let organisms through and could be cellulose pads or a cartridge, and is relatively inexpensive. Home wine, ,,, why bother filtering? grandpa could do good table wine with clarification techniques. ,,, Another question is volume, if you are looking at a 20 liter again why bother, ,,, are you doing commercial wine?

 

[plato25]

@plato25
* degassing, what I do is a cork with a check valve. The definition of good enough is that it can hold a -5 inch Hg/ 15 Kpa vacuum for thirty minutes. Many home wines have more CO2 than this and you can’t taste it, ,, but I vacuum cork.
Transferring with vacuum also will degas. ,,, I intentionally try to hold CO2 in the wine till I am ready to bottle.
* yes you could push with CO2, this isn’t part of the specification of normal carboys. I would NEVER use high pressure on home grade glass. Commercial wine will flush the tubes and filter with nitrogen and have a dissolved oxygen specification and run the filler with nitrogen. ,,, home wine will add metabisulphite, it is hard to keep oxygen out with 20 liters.
* for lots of wine you want a commercial HVAC vacuum pump (pulls -22 or -24 inches Hg) wired for your power. I mainly do gravity assisted so I am using inexpensive (20£) 12V DC which pulls -22 inch Hg.
* you didn’t say it but use a vacuum gague, always have a liquid trap before the pump
* filter? For what purpose? Sterile is called absolute filtration (0.45 micron) and is used commercially. A polishing filter will let organisms through and could be cellulose pads or a cartridge, and is relatively inexpensive. Home wine, ,,, why bother filtering? grandpa could do good table wine with clarification techniques. ,,, Another question is volume, if you are looking at a 20 liter again why bother, ,,, are you doing commercial wine?

@plato25
* degassing, what I do is a cork with a check valve. The definition of good enough is that it can hold a -5 inch Hg/ 15 Kpa vacuum for thirty minutes. Many home wines have more CO2 than this and you can’t taste it, ,, but I vacuum cork.
Transferring with vacuum also will degas. ,,, I intentionally try to hold CO2 in the wine till I am ready to bottle.
* yes you could push with CO2, this isn’t part of the specification of normal carboys. I would NEVER use high pressure on home grade glass. Commercial wine will flush the tubes and filter with nitrogen and have a dissolved oxygen specification and run the filler with nitrogen. ,,, home wine will add metabisulphite, it is hard to keep oxygen out with 20 liters.
* for lots of wine you want a commercial HVAC vacuum pump (pulls -22 or -24 inches Hg) wired for your power. I mainly do gravity assisted so I am using inexpensive (20£) 12V DC which pulls -22 inch Hg.
* you didn’t say it but use a vacuum gague, always have a liquid trap before the pump
* filter? For what purpose? Sterile is called absolute filtration (0.45 micron) and is used commercially. A polishing filter will let organisms through and could be cellulose pads or a cartridge, and is relatively inexpensive. Home wine, ,,, why bother filtering? grandpa could do good table wine with clarification techniques. ,,, Another question is volume, if you are looking at a 20 liter again why bother, ,,, are you doing commercial wine?

Hi

Many thanks for your detailed and interesting reply. It all makes absolute sense. No need for all this paraphernalia for small quantities at home.

I’m just an addicted to hedgers for no real reason.

As a grandpa who made (many years ago) some of the best wine I have ever tasted I concur. Drunk at 10 years after bottling. Dried bilberries as per CJJ Berry’s excellent book, no fuss no gadgets, no degassing etc. result? Superb!

As is often said patience is the most important ingredient.

Thanks again your excellent advice.