Powdery mildew on grapes - should I toss the grapes?

[Obbnw]

So...

I didn't know the powdery mildew affected the grapes directly. Last year I had some powdery mildew on my tempranillos but it didn't affect the berries at all so I didn't think it would affect the berries directly. Ignorance is bliss. Last year the mildew didn't show up till late and apparently it will not affect the grapes if the sugar is over a certain level.

This year I was watching and trying to control the mildew. Never got bad but now that the grapes are ripening it definitely had an effect on the grapes. Many had split and are small.

I picked a some of the grapes and mashed them, sugar was 23 brix, ph about 4.2. The juice tastes fine but the internet says it will impart an "oily viscous" mouth feel.

Anyone have experience using grapes affected by powdery mildew? I'm wondering if I should just toss them.

I'm not a super taster so I don't pick up on some of the subtleties others do but what does "oily viscous mouthfeel" mean? It sounds bad, how bad is it?

 

[balatonwine]

First, it depends on how much your grapes are infected. Second, the type of wine you make.

I have had powdery mildew, on my white grapes. If it is mild, I still use them, but I crush and press immediately. Never soak. Never noticed any off flavors or bouquet normally attributed to mildew. In fact such grapes still created very good wines. Do note, I have had off flavors and bouquet for other reasons, even on "perfect" grapes --- I mention this simply to indicate I do know the difference between mildew problems and wine making errors.

So, if the mildew is not too bad (post a photo for us to consider) I would go ahead and try to make wine, but I recommend simply not soaking the grapes on the skin too long, it at all. That is, don't try to create a red wine. Rather, crush and press immediately and create a Rosé

 

[Obbnw]

Thanks for the response. Seeing as I crushed them and put them in the freezer for a future red wine I think I'll just toss them. My plants are scattered around the yard and the microclimates vary so ripening is not consistent. Last year I would pick plants when they reached a level I thought was good. We would destem them, crush them and put them in the freezer till all the plants were picked. It worked great, I liked the wine and it let me spread the harvest and work out over 4 weeks.

Overall it isn't a large quantity. I was just hoping to do a single grape ferment this year but probably won't have enough to do a 7 gallon batch of all tempranillo. I'll either do a smaller batch or just add some of the malbec. We'll see when the harvest is complete.

The worst ones looked like the picture in the following but my leaves looked better. It seems like the infected ones ripened much quicker than ones not infected or only minorly infected so I didn't mix in too many nice clusters. So it goes, live and learn....

https://www.google.com/url?sa=i&sou...aw3m9wExjod06cWcnMP_e-1E&ust=1568237947073515

Next year I'll try a more traditional training system and stay on top of spraying. I like the wild look so I wasn't really trying to train them to ease harvest and minimize disease pressure. I'm anti spraying so if next year is also bad I'll probably just replant a less susceptible variety. Only 7 plants had damage and the location (against a solid fence) makes it difficult to get good airflow. I have 2 other Tempranillo plants in locations that get better air flow. They had some powdery mildew on the leaves but none of the grapes look infected and the malbecs seem fine.