MLF not progressing?

[JBP]

Tale of two juice buckets:
I fermented two Chilean juice buckets this spring - a syrah and a zin. Both were co-inoculated with BM 4x4 and CH16 (from same packet) a couple of days later. Additives were the same for both - FT Rouge, Opti Red, Fermaid K 1/3 way through fermentation). They have been doing their thing side by side in my winemaking area. Both finished primary fermentation nicely and have been properly topped off with airlock for 2 months while continuing MLF. Using Accuvin malic acid test strips, the Syrah is complete. The zin was at 75mg/L at one month and has not changed.

Data on the zin: SG 1.090, finished 0.992 (ABV 12.8% - a tad low); temp for past 2 months ~70 degrees; pH tested today 3.04 (not sure how to interpret given still full of CO2?); SO2 not tested, but have not added any sulfites at any point.

Only other difference was that I added an All Grape Pack to the Zin at the beginning of fermentation.

Any explanations and - more importantly - any suggestions?

 

[cmason1957]

It is probably worthwhile to remove the CO2 from the sample and retest the ph. You souks be able to remove it by heating it in the microwave, slowly 20-30 seconds at a time. Allow it to cool to room temp. A ph below 3.2 and MLF probably won't start or complete. The SO2 might also be needed, but both free and bound and the bound is much more difficult to determine.

 

[JBP]

Thanks - will recheck pH tomorrow as suggested. If it is still low, will address that.

 

[JBP]

Ugh. Cheap pH meter decided to be calibration challenged. Can calibrate neutral and acid solution, or neutral and base, but not full range (error reading). Calibrated neutral and acid - was reading those consistently, so went ahead and tested zin after gentle heating/degassing. Still very acidic - pH of 3.15. While not trusting my pH meter fully, the answer would explain MLF failure. Aside from getting a better pH meter, advice on next steps? Degassing will help a bit, but insufficient on its own (and no k-meta to protect it). Read mention of potassium carbonate on another thread with not much detail.

Thanks in advance.

 

[JBP]

Bringing this back up and hoping for some insights. Perhaps just waiting to see if a new pH meter (on order) gives a better answer? Pretty sure I have a low pH problem that prevented MLF.

 

[cmason1957]

Low PH will prevent MLF from happening certainly. Should you try to increase the PH, maybe. first thing is how is the taste of it now?? I might guess sharp, but is it so sharp that you can't stand to drink it? Shooting for perfect numbers is often not the best answer. But, if you decide to try the potassium bicarbonate to increase the Ph, it can be done. After you determine how much to add, cut it in half and try that first.

 

[JBP]

Thanks for the response. Taste is sharp and neither pleasant or unpleasant. A bit of aftertaste (not in a good way). Guess I am not quite experienced enough on this one to determine if it will age out. This may be one of those upticks on the learning curve. Experience is a good teacher, if not a kind teacher.

I think what I am hearing is that if the taste is reasonable and I think that age/oak will bring it to a nice drinker, I should give up on MLF (ie - Kmeta, rack). Less sure what would compel me to keep pursuing MLF...

All else fails, I have plenty of red wine vinegar for holiday gifts this year.

 

[Michael T]

Never give up. Use vinegar as an absolutely last resort. If you have to go to vinegar it will make a wonderful bait to go in fruit fly traps.

 

[montanarick]

If it's too bitey, you can always backsweeten to taste. make sure you add k-meta then lysozyme and sorbate before adding more sugar. I know they always tell you not to add sorbate after MLB has been added to your wine but if you add lysozyme first it will kill all the MLB and you won't have to worry about production of geranial. good luckl

 

[JBP]

Thanks, all, for the comments and help. The weekend update is one lesson learned and a new path forward. Lesson learned - equipment matters. Cheap things are, well, cheap. The new pH meter arrived (Apera Instruments- AI311) - no comparison with the old one. Caliberated easily, functioned flawlessly - and gave significantly different numbers.

pH - 3.31
TA - 1.23 g/L (used pH meter to test as in post here) - pretty high and aligns with taste, as it should

Note that I forgot to degas sample, so CO2 likely influencing numbers some. I rechecked Accuvin strip again - still no change. Plan is to re-incoluate with MLB (VP 41 this time as it is available) and try again - seems the best way to avoid MLF in the bottle eventually. I am a bit worried about time and lack of sulfites (over two months since started), although I have kept things well topped off and closed up except for testing.

Unless, of course, more experienced colleagues here have other suggestions.

 

[cmason1957]

Two months is nothing to worry about. When you get to a year, maybe. Just keep it topped up well and limit oxygen exposure. Try the VP41, it can't hurt. Temps up. Use some mlb nutrients, stir gently once or twice a week.

Worries about mlf in the bottle can be eliminated with lysozyme and slightly higher kmeta use.

 

[JBP]

Wow - that is a serious reset to my mental timeline. Tincture of time and patience. Just to be sure I am absolutely clear - no kmeta while tending/waiting for MLF to complete? Even if a year?

Thank so much.

 

[cmason1957]

It will probably be done in about 6-8 weeks, if your temp is around 70 F. However, it can take much longer. Think to the caves of France, temp drops to 60F (or lower) during winter time and mlf finishes up in the spring or summer. I had one take 6 months and it was among the best wines I have ever made. Top up, don't worry. It's all good.

 

[montanarick]

you might want to think about investing in a chromatography kit (if you haven't already) - that way you can test to see if MLF is complete. Got mine from Presque Isle wine www.piwine.com