Natural Fermentation and Lactic Acid Bacteria

[Raptor99]

I did another deep dive today. I have been thinking about the application of Lacto-fermentation (which makes really awesome pickles!) as part of the wine making process. If you do MLF, you already use one specific type of lactic acid bacteria (LAB), which is Oenococcus oeni. That particular type of LAB is able convert malic acid to lactic acid. Lactic acid adds body and a smooth mouth feel to wine.

But there are many other types of LAB, such as the ones used to make yogurt, that create lactic acid from glucose and fructose, and are not able to use malic acid.
So I have been thinking, what about using Lacto-fermentation as a preliminary step to:

• lower pH
• add lactic acid for body and mouthfeel
• add depth of flavor

Then I realized, that those who are doing "natural fermentation" by using whatever is already on the fruit are almost certainly getting some lacto-fermentation along with yeast fermentation. LAB is usually present on fresh fruits and vegetables, which is why you don't need to inoculate fermented pickles with LAB. That could explain some of the complex flavors produced by natural fermentation (when it goes well).

This idea is still in a preliminary stage, but I am working on an experiment to test this method. Here is an article on using lacto-fermentation as a preliminary stage in making beer: Brewing With Lactobacillus - Brew Your Own. And here is one one a two-stage fermentation process used to make hard kombucha: How to Make Hard Kombucha (Alcoholic Kombucha Recipe) What would it be like to use such a two-stage process to make wine?

I think that there are two possible sources for LAB:
1. The natural fermentation method, using whatever is on the fruit
2. Inoculate the fruit with some whey drained from yogurt to provide LAB

 

[Rice_Guy]

You would get a cleaner culture if you used a “live culture” yoghurt as Dannon. Natural pickles probably could be used but might make more funky flavors.

What if? In yoghurt production sugar (lactose) is metabolized to produce acid. The increase in acid causes the casein to coagulate. , , , , This means that in a wine situation there would be an increase in total acidity and a drop in pH. Beer is in the mid fives therefore from a safety point of view adding acid makes it a safer food. From a taste point it is acceptable. , , , , Grape wine frequently has more acid than we want so this would be going backward. Lower Titratable acidity fruits like peaches or mulberries might benefit from dropping the pH so they could be tried.
Body? When I hear the term I think 1) viscosity building agents, for viscosity I would test glycerin or gum arabic (or zanthan) 2) long flavor notes from tannin/ added polyphenols. Lactic acid doesn’t especially grab the taste buds and give long memorable flavor.
Complexity? sure it would and threshold levels of vinegar or black pepper/ Hungarian paprika/ ginger/ etc would too

 

[Raptor99]

Thanks for your helpful reply.

Grape wine frequently has more acid than we want so this would be going backward. Lower Titratable acidity fruits like peaches or mulberries might benefit from dropping the pH so they could be tried.

I don't make grape wine, so I was thinking of other fruit wines such as peach. The first step is to do lacto-fermentation on some fresh peaches and see if I like the flavor profile. If and only if I think it would make good wine, I would go on to step two. I think that this might work for certain low acid fruits. In that case, I would be adding some lactic acid in the place of acid blend.

I already use glycerin and oak in some of my fruit wines.

 

[BigDaveK]

Interesting idea.
If you pursue this please share your results!

I make yogurt almost weekly. My "seed" yogurt was Chobani with 6 active cultures - L. Rhamnosus, S. Thermophilus, L. Bulgaricus, L. Acidophilus, Bifidus and L. Casei. Is one better than the others, like yeast strains? Would a yogurt with fewer cultures be better? Hmm, don't know.

The first step is to do lacto-fermentation on some fresh peaches and see if I like the flavor profile.

I wonder if the flavor at this step would give an accurate sense of the results? Perhaps this would be an intermediate taste that may or may not be pleasant?

I'm not going to do anything with this but now the idea is in my head. Thanks a lot.

 

[Raptor99]

@BigDaveK I'm always glad to inspire another "I'm going for it" post

Since you asked, here is an article with a nice chart of different types of lactic acid bacteria: https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/lactobacillales

The legend under the chart identifies three types of glucose fermentation:
A, obligately homofermentative
B, facultatively heterofermentative
C, obligately heterofermentative

Homofermentive (A) produces only lactic acid and CO2. Herterofermentative (C) produces lactic acid, acetic acid, ethanol, and CO2. Facultatively heterofermentative can do either type, depending on conditions.

The chart covers only genus Lactobacillus. The two species required by law for a product to be sold as "yogurt" are Lactobacillus bulgaricus (Lb. delbrueckii subsp. bulgaricus) and
Streptococcus thermophilus. Both are obligately homofermentative.

Have fun!

 

[BigDaveK]

@BigDaveK I'm always glad to inspire another "I'm going for it" post

Since you asked, here is an article with a nice chart of different types of lactic acid bacteria: https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/lactobacillales

The legend under the chart identifies three types of glucose fermentation:
A, obligately homofermentative
B, facultatively heterofermentative
C, obligately heterofermentative

Homofermentive (A) produces only lactic acid and CO2. Herterofermentative (C) produces lactic acid, acetic acid, ethanol, and CO2. Facultatively heterofermentative can do either type, depending on conditions.

The chart covers only genus Lactobacillus. The two species required by law for a product to be sold as "yogurt" are Lactobacillus bulgaricus (Lb. delbrueckii subsp. bulgaricus) and
Streptococcus thermophilus. Both are obligately homofermentative.

Have fun!

Thanks for the link!
I make yogurt, kambucha, and fermented vegetables and it baffles me why I never did a deep dive on the process. Will the information influence my wine making? Don't know. In the very least it will give a wonderful understanding of my other interests and for that I'm very appreciative. Thanks again!

 

[Peggy Billingsley]

Thanks for your helpful reply.

I don't make grape wine, so I was thinking of other fruit wines such as peach. The first step is to do lacto-fermentation on some fresh peaches and see if I like the flavor profile. If and only if I think it would make good wine, I would go on to step two. I think that this might work for certain low acid fruits. In that case, I would be adding some lactic acid in the place of acid blend.

I already use glycerin and oak in some of my fruit wines.

What do you mean by a lacto fermentation of peaches? How do you do it? Mash peaches and add yogurt? Or add peaches to large amounts of yogurt whey?

 

[Raptor99]

@Peggy Billingsley Here's an overview: How to make lacto-fermented fruit, with recipes

Lacto-fermentation makes use of the naturally occurring bacteria on the fruit to ferment and produce lactic acid. You can also add some yogurt whey to the fruit as a starter.