WineLovers Discussion Group

We are almost ready to harvest and I have some questions.

1. Is there a strain of yeast that works better than others in a high TA, low pH must? We may have to harvest (cabs, syrahs, merlots) ahead of rain, TA about 1.0, pH about 2.9, brix at 23.

2. Any reason not to do malolactic fermentation before primary? If we can't get the primary started because of low pH, we were thinking of doing maololactic first to adjust the pH.

3. I live in a very alkaline area. How the hell am I growing high acid grapes in alkaline soil?

TIA

Though generally clueless about your questions, I might have a source to answer the first.

My husband and I are planning to move to the Willamette Valley and make a little wine. So he's been reading (I think this is the title) "From Vines to Wines." I distinctly remember him talking about their section on yeasts and which ones should be used for different pHs and such. Might be just the source you need!

And then when we're winemaking, I'll be back with my own questions

1. Here's a link for yeast strains:
http://winemaking.jackkeller.net/strains.asp
I'd stay away from Lalvin 71B as it has been known to produce banana aromas, especially in Beaujolais. Some strains are not recommended for concurrent malo-lactic fermentation and some require addtions of chemicals to supply sufficient nitrogen, othersise, H2S and mercaptans may form.

2. M-L requires a low level of SO2. To try to do M-L before primary is inviting spoilage with no alcohol present. I'd do it concurrent or even after primary. With a TA of 1.0 you may have trouble starting M-L. I'd adjust to about 0.8 using potassiom bi-carbonate before starting M-L.

3. I don't think the pH of the soil affects the pH of the grapes as much as ripeness. I believe it affects how many nutrients are absorbed from the soil, which affect leaf and cane growth.

With 2.9 pH getting ml started won't be easy. In any event, the preferred method is simultaneous ml and primary fermentation. You should not add SO2 until after the fermentations are complete.

You need to look up the stats for the many yeast strains and their interaction with various types of conditions. If the grapes are healthy and nutrition is balanced, starting the primary shouldn't be much of a problem--I used to get 2.9 regularly in the Finger Lakes, often with lower than 23 Brix.

The acidity (and pH) in grapes is influenced a lot by climate and canopy/crop size maintenance. It seems you are harvesting a little early, which would give you grapes that had yet to reach ripeness and so would normally be higher in acidity and lower in sugar.

I'd really try to keep them hanging for a while longer, to let the acid
decrease. Acid decreases as sugar increases, and even at 25 brix you'll get better balance and riper phenolics. How much rain do you expect? As I recall, SLC gets some showers but dries up quickly this time of year.

ernie in Berkeley wrote:I'd really try to keep them hanging for a while longer, to let the acid decrease. Acid decreases as sugar increases, and even at 25 brix you'll get better balance and riper phenolics. How much rain do you expect? As I recall, SLC gets some showers but dries up quickly this time of year.

I agree 100% The better the grapes, the better the wine.

Thomas;

You should not add SO2 until after the fermentations are complete.

The book we are using (I think it is From Vines to Wines, by Jeff Cox) suggests sulfiting before primary to kill unwanted yeast strains, then allowing some time to pass for the sulfites to blow off before adding yeast. Do you suggest skipping this step and hoping what we add outcompetes the native yeasts?

I

f the grapes are healthy and nutrition is balanced, starting the primary shouldn't be much of a problem--I used to get 2.9 regularly in the Finger Lakes, often with lower than 23 Brix.

Our book also suggests that starting primary below pH 3.0 may not work. Obviously, you have experience that contradicts this. Perhaps the book's author has been unable to start primary with pH< 3.0 andresidual sufites? Or pH<3.0 and TA higher than his reccommended range of 0.6-0.8? Any guesses on this?

TIA

Howie, I've learned from several sources that high pH soils (alkaline) yields low pH wines and vice versa. I don't know how scientifically sure this (anti)correlation is, though, but it has been claimed by several people, Oliver Humbrecht being one of them.

Cheers, Anders

We don't expect a general widespread soaker, but our T-showers can dump a half inch or more in a few minutes in any given location.

What do you think the waiting period would be after such a dousing? I assume a light sprinkle would not have any significant effect?

Our early-season control of powdery mildew seems to be working - no sign of problems there...

I've started many fermentations with pH as low as 2.7 and a lot more acid than you are reporting using Premier Cuvee, with or without pre-fermentation additions of SO2. Make sure you use appropriate nutrients, and enough of them. My experience with M/L suggests starting M/L at end of primary yeast fermentation, keeping the temperature at 70F or a little higher, and adding M/L nutrient. I use Vina Flora Oenos direct addition freeze dried M/L culture and Bactiv Aid M/L nutrient. Howie's suggestion that you use potassium bicarbonate to raise the pH a little is good advice, in my opinion. I usually shoot for a pH of 3.1 or more before attempting to start M/L. Acid levels are not as important as pH regarding M/L fermentations.

Jim,

I do not dispute Alan's or Howie's advice, although I am not a fan of calcium carbonate for what it is possible it can do to the mouth feel of a wine--chalky.

I meant that if you want to get ml going, which at 2.9 pH is a monumental task (best range is 3.1-3.4), you cannot add SO2 because that would surely prevent it from starting.

Also, there is a school of thought that does not like adding SO2 before primary fermentation; but yes, by doing that you can be running the risk of the natural yeast taking over. Having said that, I know that there are cultured yeasts on the market that don't give the natural kind a fighting chance to survive...

If you have healthy grapes and weeks to go before the normal harvest, maybe you could try waiting it out.