Stubborn pear wine won't clear

[MiBor]

I'm seeking advice from experienced country wine makers on what to do to clear a friend's pear wine. I brought the 2 6-gal carboys to my house so I can figure out what to do with it, as I'm running out of ideas on what to tell my friend to try.
The wine was made last November from ripe Bartlett Pears that grow on my friend's property. I participated in the winemaking process so I know the details. The must (crushed pears, water and sugar) had 20 brix before fermentation and 10 lbs. of pears were used per gallon of water, along with 1/2 lbs. of sugar to bring up the lacking specific gravity. The pH was 3.7 and TA around 0.7% after adding acid blend. The fermentation was initiated with EC-1118 and took about 2 weeks to ferment dry. A hefty dose of pectic enzyme was added to the must and allowed to work for 8 hours before the yeast was pitched.
After pressing, the wine was racked a couple of times off the sediment, SO2 was kept at about 80ppm and bentonite was added to help with clearing. About a month ago I gave my friend a couple of packets of DualFine (K+C) and he added them according to instructions. I expected the wine to start clearing soon after, but it didn't.
Today I went there and I decided to take the pear wine and try to troubleshoot it in my cellar. I will attach a couple of pictures to show what I'm talking about, one of the pear wine and another of a clear wine for comparison. Any ideas and suggestions are much appreciated.


Clear wine



Pear wine

 

[cmason1957]

I made a peaf wine one time that took two triple doses of pectic enzyme after fermentation to clear. Like you we had added pectic enzyme prior to fermentation. It is a cheap thing to try.

 

[crushday]

More time?

 

[HillPeople]

I'd give Sparkolloid a shot.

 

[winemaker81]

If bentonite and K&C didn't do the job, there's something else going on. I agree with Craig, add more pectic enzyme, a double or triple dose. AFAIK, it won't hurt the wine.

 

[Rice_Guy]

I agree to the pectic enzyme treatment, pear is relatively high in pectin.
I see that your pH is high with TA at a normal level. A less common issue is having turbidity produced by a wild lactic acid bacterial infection. Has the pH increased since the fermentation started?

 

[Raptor99]

Pear wine is often difficult to clear, and I think that it is mainly due to pectins. I don't use clearing agents, but I do bulk age my pear wine for at least 6 months. Pectic enzyme is key, but I think that bentonite will remove pectic enzyme, so you might need to add it again after treatment with clearing agents.

A hefty dose of pectic enzyme was added to the must and allowed to work for 8 hours before the yeast was pitched.

I do this as well, to give the pectic enzyme time to work. For pear wine, I have started giving the pectic enzyme 24 hours to work before pitching the yeast. But the effectiveness seems to depend on the temperature (see below).

Before I got my wine room set up I was making wine in my kitchen. In the winter, the temp was around 68 degrees F. I had several wines that refused to clear. When summer came, the average temp in my kitchen was more like 75 degrees. Several wines cleared within a few weeks once it warmed up. I have never seen any documentation on this, but it seems to me that pectic enzyme works better at warmer temperatures. It might not do much at 65 degrees F, but it might work well at 75 degrees F.

Here's a thread on that topic: https://www.winemakingtalk.com/threads/pectic-enzyme-and-temperature.73864/

 

[Raptor99]

I found a graph of effectiveness of pectic enzyme vs temperature: https://www.researchgate.net/figure/Effect-of-temperature-on-activity-of-pectinase_fig2_319639587

 

[MiBor]

Thank you very much for your responses. I don't make fruit wines myself and if I didn't promise my friend I'd help with his first pear wine, I wouldn't be asking for help on this matter. It is a good learning opportunity for me though, so I'll put in the necessary effort for fixing this wine.

Anyway, I think I came up with a plan on what to do:
I moved the 2 carboys into my home office which stays at a constant 74-75F in the summer, to let the wine's temperature normalize before adding a triple dose of fresh pectic enzyme. Depending on how it looks in a couple of weeks, I may add another triple dose of pectic enzyme or use newly bought Sparkolloid to finish clearing the wine. Once clear, I may cold stabilize it and may or may not filter it for added clarity. I'm a little apprehensive about filtering since @Nebbiolo020 mentioned that it damages wine and strips a lot of aromas and flavors, which are not very strong in pear wine to begin with.

I just re-checked the pH and TA of the wine and the changes are insignificant (pH3.63, TA0.75%). I don't think the cloudiness is due to a slow malolactic conversion because we added Bactiless to this wine in January and the numbers are not much different from what we measured soon after fermentation.

I'll post periodic updates and pictures of the progress, as others may find this thread useful in the future.

 

[winechef]

could try cold crashing that should make solids drop more.

when I add my pectin enzymes for certain fruits I start with at least 2 tablespoon per 6 gallons. I wait 24 hours before adding extra tannins if you use them. before yeast. I add bentonite after fermentation not during. after 3 months if it hasn't cleared I add 2 more tablespoon of pectin enzymes wait a few days then if still cloudy might use bentonite again but never had to.

is the flavor off or does it smell and taste good?

 

[MiBor]

is the flavor off or does it smell and taste good?

The smell and taste of the pear wine are fine. I sweetened a glass to my taste and drank it slowly and I think it is actually a good fruit wine, aside from being cloudy. I'll be adding a triple dose of pectic enzyme tonight and hope for the best. The package recommends 1/2 tsp per gallon, but I'll up that to 1.5-2 tsp per gallon just to see what happens. I'll post updates as I see a change (or not) in wine clarity.

 

[winechef]

Could rack it once more too, sometimes that helps, after adding pectin rack it should fix it.