Other Lesson Learned: Gentle with Grape Skin Pack

This is my public service announcement for the day. I learned a lesson this week about proper treatment of the Grape Skin pack that I think is worth sharing. Bottom line: if you try to squeeze everything you can out of it while in primary you chance having a protein spike which can ruin your day till you know what it is. My lesson: gently push down the grape skin pack each day and follow with a gentle stirring.

Here's how I learned this:

During primary of a WE Eclipse Lodi 11 Cabernet I used my spoon to squish the grape skin pack against the side of the bucket each day so as to extract all the sugars and flavors I could. When I removed the pack it basically had little left in it besides seeds and stems.

All seemed fine and then I moved it to secondary on the fifth day at .994 to be sure that I'd still have a little fermentation action left in secondary. On about the 3rd day in secondary, I noticed a sheen on top of the wine. Not too bad, but like a film of oil on water. After about 6 days it was thicker. I tried sucking it out, but it grew right back. About this same time I noticed a bright white line around the edge of the carboy at the wine level.

By this time I had already searched all over for anything I could find like this. I didn't find much, and the only thing that kept popping up was Mycoderma, though I didn't ever find any good pictures of it to compare with what I had.

I noticed that if I tipped the carboy to the side, the white line became a wall of milky white cream on the inside of the carboy. About that time I found this thread on here:

http://www.winemakingtalk.com/forum/showthread.php?t=51168

That showed the same type of cream but much worse. Fortunately he got an answer from GV about it being proteins. I was talking with WE about mine as well. They weren't sure what mine was as the protein issue should be rare.

We decided that I should go ahead and move to Stabilizing, which I did last night. After stirring and adding the Sorbate and KMeta I let it sit and some nasty looking crud came to the surface. This stuff was about a 1/4 thick and fairly solid looking, not like foamy bubbles.
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UPDATE March 2016: I just found a Tim Vandergrift blog post that talks about the 'crud' I mentioned above. He has a photo that shows much better what I had. The 'crud' or as he calls it 'goo' is the result of there being too much CO2 left in the wine when the KMeta and Sorbate were added. Essentially the excess CO2 encapsulated the Kmeta and Sorbate and floated them to the top. His recommendation if that happens and you see it in the first day or so is to re-whip the gas, crud and all, and it all go back to how it should be. see this: https://winemakermag.com/blogs/what-do-you-do-with-floating-goo

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I sucked as much of that off as I could and then added the Chitosan and crossed my fingers.

This morning all the white is gone, the film on top is gone and the wine is clearing normally. After talking with WE we decided that by trying to squeeze everything out of the Grape Skin pack I over exposed the wine to the proteins and tannins in the pack. I think the crud stuff that came up last night was similar to the protein crud that comes out chicken or turkey bones when you boil it for soup.

Now my wine has a strong tannin taste to it. That's good in that it will protect it from oxygenation and force me to keep it stored for a good long time to break it down (or throw in some egg whites or some such stuff).

But the lesson for me is, follow the directions and just push down the grape skin pack. I won't try to milk everything I can out of it, or I will end up with some nasty looking 'milk' in the wine.

I hope this helps others who might see the same thing in their wine and can't figure it out.