Can someone help me better understand this. I am reading a book that states it's also called secondary fermentation. But also talks about innoculating with bought bacteria for the purpose of putting your wine through MLF. States some whites are put through MLF and all reds are. The fascinating thing is thar it described wines that are bottled can turn fizzy and off tasting bc they go through it in bottle which sounds a lot like what's happened to my reisling. But how does this compare to not allowing enough time prior to bottling. My reisling was bottled too early. I only let t go two months after primary. So what if you let your wines sit six months before bottling? Which is what I plan on doing from now on. Do wines naturally go through MLF? Or do I need to add something to it to ensure they've gone through this?
Explain malolactic fermentation
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jgmillr1
Well-Known Member
Malolactic fermentation is process of lactic acid bacteria converting the malic acid in wine into lactic acid. It produces a small amount of CO2 and sediment, but nothing like primary fermentation. It often benefits wines by reducing the acidity, producing a soft creamy mouthfeel, and frankly just getting it over with so it doesn't happen later. Most wineries innoculate the wine with a dried bacteria powder available from most wine supply stores. It can also happen naturally during barrel aging, since the barrels are likely teaming with the malolactic bacteria from years of use. The bacteria prefer low sulfite levels and warmer temperatures. They can complete the process in a couple weeks. The downside of malolactic is that it can subdue the fruit aromas, so this may not be great if you want a fruity style typical for Riesling.
Malolactic can be prevented with proper sulfite dosing. Be careful not to allow the wine to go through malolactic if you have added sorbate, since that will produce the dreaded 'geranium taint' defect.
For your Riesling, I would guess it went through bottle refermentation due to yeast becoming re-energized and continuing the fermentation after bottling. Sorbate is a good preservative that inhibits yeast growth. It is typically used in sweet wines to prevent bottle refermentation. You also need to be sure to keep your sulfite levels up to prevent unwanted bacteria from also working on the sugar. So, a longer settling period will drop more yeast out of your wine and, in combination with the sorbate, be a good means to prevent this from happening again.
Malolactic can be prevented with proper sulfite dosing. Be careful not to allow the wine to go through malolactic if you have added sorbate, since that will produce the dreaded 'geranium taint' defect.
For your Riesling, I would guess it went through bottle refermentation due to yeast becoming re-energized and continuing the fermentation after bottling. Sorbate is a good preservative that inhibits yeast growth. It is typically used in sweet wines to prevent bottle refermentation. You also need to be sure to keep your sulfite levels up to prevent unwanted bacteria from also working on the sugar. So, a longer settling period will drop more yeast out of your wine and, in combination with the sorbate, be a good means to prevent this from happening again.
Sorbate is used as a yeast inhibitor and added shortly before bottling a sweetened wine camden tabs is the most common homebrewer form of sulphites ( i forget if it is kms or another _ms), which when used in the correct doses along with proper handling of the wine it will protect a wine.
gregbathurst
Well-Known Member
If you want to be sure you need to innoculate, but if you can tolerate a small degree of uncertainty you can just wait, providing the temperature is warm enough. MLF will usually happen naturally, but not always, and it is hard to put a precise number on the uncertainty.
it can happen naturally but the conditions for it to occur are border line safe for a wine in my mind (the lethal limit of sulphites in wine for ML bacteria is 60ppm and that is usually what i ad when i finish a ferment unless i intend it to go through malo) so inoculating it with malo allows protection since the bacteria produce CO2. and if you have never done Malo in your wine area or building there might not be a strong enough "wild" presence to make it strong enough in time. I recommend inoculating it
Only wines you want the malo to proceed but CAN (doesn't mean should) be done to most wines, and malo likes it around 68-77.
Take a look at this link. It is more in-depth but if you look at ranges for the temps. malo like and other info. This is from commercial winery supplier so take claims of results with grain of salt.
http://www.scottlab.com/pdf/ScottlabsHandbook2016.pdf
Take a look at this link. It is more in-depth but if you look at ranges for the temps. malo like and other info. This is from commercial winery supplier so take claims of results with grain of salt.
http://www.scottlab.com/pdf/ScottlabsHandbook2016.pdf
I'm going to try to explain my future proposed process without a super long paragraph. Take identified juice and add pectic enzyme (when necessary ) wait 12 to 24 hrs. Add camden, wait 12 to 24hrs. Add yeast. Carboy upstairs where temps are warmer. 2 weeks wait. Rack to glass carboy. Move down to basement for 1 month. No the initial 2 week ferment may go to basement with white wines. Ok so 1 month ferment. NOW rack off Lee's, move to 2nd floor for warmer temps and innoculate with Malo bacteria when planning to use it. Once thats done, rack and move back to basement for a 4 to 5 month age period, clearing period racking every 60 days unless I get heavy sediment before that. Following a every other racking camden addition and doing what I can to top off to reduce head space. Finally racking into bottle bucket with camden addition and bottle. Does that sound like the right process? I've read that you can use fining agents in the early stage of fermentation. Kinda confused with that. I usually add sparkalloid near the end
i suggest only slight modifications. use hydrometer so you can see better for sure when all sugar is consumed. and for racking once done the ferment you only really need to wait 3-4 days for the heaviest stuff to drop out. and when inoculating with Malo.. listen to the carboy and watch it (you can see when MLF is active because it has very faint crackling almost like rice crispies cereal) to identify when it is finished it will no longer make that sound. (you look crazy listening to barrels and tanks sometimes but it is the quick way to hear if things are working or are happy, let the wines talk to you). I have to admit i hate to judge completely on people's process because I am used to commercial winemaking and even use similar methods at home.
Thanks. Yes I use a hydrometer. So, am I looking for 1.0 as a signal it's done alcohol fermenting or the traditional 3-5 days with no change in readings? Never done MLF before I don't know that sound but I sort of get what you're saying. I have heard the fizzing of the ferment with the rie sling and other low foaming ferments. Apple cider too. Hard to see the bubblessings but can hear the fizz
jgmillr1
Well-Known Member
I've always used cane sugar and not had any trouble.
jgmillr1
Well-Known Member
You can use some sort of glucose containing sugar product (eg. dextrose, maltose) or fructose powder/liquid (eg. corn sugar). Since yeast are glucophilic, they preferentially metabolize glucose over fructose so you may run into fewer issues with a fructose-based back-sweetener. But if you have viable yeast in your wine, you will still have problems even with a fructose-only addition.
One possibility that I've never hear of anyone using, is using a pentose sugar addition. Looks like you can buy these ribose sugars on Amazon. Yeast can't metabolize pentose sugars, so it would seem to be a good agent for back-sweetening. Don't know how it tastes in solution or if it is cost effective.
Sometime last December either Coke or Pepsi re-introduced a limited run of cane-sugar sweetened soda as a special treat, rather than the high-fructose corn syrup they usually use. The fact that this is considered a special treat should reinforce that cane sugar tastes better than corn syrup as a sweetener.
As a separate note, since this thread had started with a question on malolactic, one can assume that you are wanting to backsweeten a wine that has been through malolactic. You will need to use sorbate to prevent yeast refermentation and it is critical that you use a properly high enough sulfite addition to kill off the malolactic bacteria and protect the wine. The malolactic bacteria are able to metabolize the sorbate and that produces a strongly floral geranium taint to the wine. The bacteria can also work on those pentose sugars, unlike yeast.
One possibility that I've never hear of anyone using, is using a pentose sugar addition. Looks like you can buy these ribose sugars on Amazon. Yeast can't metabolize pentose sugars, so it would seem to be a good agent for back-sweetening. Don't know how it tastes in solution or if it is cost effective.
Sometime last December either Coke or Pepsi re-introduced a limited run of cane-sugar sweetened soda as a special treat, rather than the high-fructose corn syrup they usually use. The fact that this is considered a special treat should reinforce that cane sugar tastes better than corn syrup as a sweetener.
As a separate note, since this thread had started with a question on malolactic, one can assume that you are wanting to backsweeten a wine that has been through malolactic. You will need to use sorbate to prevent yeast refermentation and it is critical that you use a properly high enough sulfite addition to kill off the malolactic bacteria and protect the wine. The malolactic bacteria are able to metabolize the sorbate and that produces a strongly floral geranium taint to the wine. The bacteria can also work on those pentose sugars, unlike yeast.
