Testing the Must

[David Engel]

Hi All,

I don't want to assume anything with the process. I have a checklist from MoreWine that suggests you check for sugar, make that correction and then test the ph and acidity. Is that correct?

Dave

 

[Raptor99]

That is the order I follow. I adjust the sugar first, then the pH. I don't measure TA, so before bottling I adjust the acidity by taste if necessary.

 

[Rice_Guy]

Taking a hydrometer reading is free and basically takes no time.
Checking the pH tells you how happy the yeast and spoilage bacteria will be. Yeast want over 2.8 and spoilage organisms mostly drop out by 3.2 and food poisoning organisms drop out below pH 4.0. ,,,
TA reflects how acidic the wine tastes and really doesn’t matter till you are ready to drink it,,, sugar and alcohol contribute sweet flavors which need to be balanced against % acid and mg of tannin.

 

[Paulie vino]

Taking a hydrometer reading is free and basically takes no time.
Checking the pH tells you how happy the yeast and spoilage bacteria will be. Yeast want over 2.8 and spoilage organisms mostly drop out by 3.2 and food poisoning organisms drop out below pH 4.0. ,,,
TA reflects how acidic the wine tastes and really doesn’t matter till you are ready to drink it,,, sugar and alcohol contribute sweet flavors which need to be balanced against % acid and mg of tannin.

Do you bother to check TA of the must? If not, when do you check the TA? This is my second year with grapes and only first time testing TA and pH, so if it's not worth testing TA I can save some time and effort.

 

[Xlev]

This is the first time I have done wine from grapes.I have tested TA in the must. I think if you need to adjust the pH that TA can be important to know before you do it,if pH is ok maybe its not super important. If you have the equipment to measure TA why not do it?

 

[winemaker81]

I don't measure TA either, just pH. I currently test pH and may adjust prior to fermentation. Like @Raptor99 I adjust by taste later on.

Full disclosure - I suck at acid titration, especially with reds.

 

[Rice_Guy]

Do you bother to check TA of the must? If not, when do you check the TA? This is my second year with grapes and only first time testing TA and pH, so if it's not worth testing TA I can save some time and effort.

Making grape wine is basically like falling out of bed. The fruit has a consistent “normal” year to year. ,,, I grow northern hybrid grape and have seen similar numbers every year. You should test one or two years to see if the vine is worth keeping.

I am on the learning curve with apples. This year I have tested a tree called my brothers woods with TA of 0.23% as well as red flesh that came out of Mom’s compost pile with a TA of 2.3%. I am always testing an unknown to see where it fits. With several years on honey gold I tested the blend that came off the crusher. With two years on sprecher road soft tannin I tested it.
I use Pearson’s square with TA if I am inventing a new blend as juneberry and gooseberry. I want an idea what the answer in before I do it with unknowns.

 

[BernardSmith]

I would argue that your taste buds are better than a pH meter when it comes to "measuring TA.. TA , in fact is a measure of the amount of acid (g/L) in a wine, but that measure as a number, say 6 -7 g/L is because we are looking for a fresh tasting wine rather than something bland or a wine so acidic that it makes your mouth pucker. We cannot in fact taste pH. That is essentially, a measure of the strength of the acids. We can taste the difference between say, malic and citric acid or taste the flavor of acetic acid.
To Winemaker81's point about the difficulty in measuring TA of a red wine, the simplest method is not to use color changing indicators but your pH meter. At a pH of 8.2 you have neutralized the acids with your addition of Sodium Hydroxide. Knowing how much NA OH you have added and doing the calculation gives you the TA by numbers, but again, taste and not numbers is always the key.

 

[ChuckD]

Ok I’m not going to check my notes so let me know if I got this… Does a TA of 6g/L = 0.6%? This switching back and forth gets me all messed up!

 

[BernardSmith]

If 1 kg (1000 g) of water by weight takes up 1 L (1000 ml) by volume, then 6 g is .6%, yes. They are the same.

 

[ChuckD]

If 1 kg (1000 g) of water by weight takes up 1 L (1000 ml) by volume, then 6 g is .6%, yes. They are the same.

Thanks. I’m finally making that conversion in my head properly. I always want to move two decimal points when going to percent.