Winery vs My readings

Perhaps one or both refractometer's were not calibrated properly for the temperature of the must?

Mine's ATC. Stood in the garage and calibrated at probably 60 ambient. In any event, I doubt you'd get a difference of 1.5 to 2.0 due to poor calibration. Could my chintzy refractometer be that inaccurate? Do folks ever take their refractometers with them to the juicehouse, so as to check the Brix for themselves?

Probably not.

Always.

'Twas just a suggestion. In a recent thread, someone complained about an even larger discrepancy between the refractometer and hydrometer readings, and (lack of proper) calibration was one of the possibilities cited.

I have no experience with "juicehouses", but I know that by the time I get my grapes home from the vineyard (about a two hour drive in hot weather), they are always consistently lower by 2-3º Brix from that claimed by the grower --- and I know him to be an honest person. I have no explanation for this, except that I use a cheap hydrometer and he uses a (very expensive) refractometer.

But why are you buying juice with such a low brix (15-17) in the first place?

This guy had his wife pick it up. Concord and Delaware. I called to get the numbers. The TA on one of them was 1.15, IIRC. TA on the other was like .90. Just a crappy year, I guess. I went the juice route 3 years ago, and had bad numbers then, too. I just went ahead with it, and the wine was undrinkable. Too acidic and bitey. There's a bunch of it STILL in the basement, er, winecellar. I know there's a ton of guys that find it convenient to just buy the juice. For a red wine, it doesn't seem to make sense to buy juice and not have the skins to ferment on. To each his own, I guess. Ken A.

I had the exact same experience, 'cept in reverse. Got my juice home and found it to be 1.8º Brix _higher_ than the vineyard reported.

In my case, perhaps the cold settling/clarifying of the juice in the tanks caused some settling to occur. Perhaps the sugar drops in the tank and concentrates. If so, then when they tapped the juice into my vessel, its sugar content was slightly higher than when first tested. Just an uneducated guess.

Or it could just be a calibration issue... I don't know. ~2º variance seems a lot. I'm working with a hydrometer while the vineyard is working with a refractometer.

-Paul

You should consider blending your too-acidic wine with one that is lacking in acid.