The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Young Culture vs Mature Culture - Question

Born2Bake's picture

Young Culture vs Mature Culture - Question

Hello, I'm a little unsure of how each of these differ exactly. Please let me know if this is correct.
I use 100% hydration, 45%ww-45%unbleached white-10% whole rye, Temp 70-72 degrees F

Also: Can anyone tell me the difference between a Levain and a Culture??

Used at the early stages of yeast production.
Mixed with a 50% discard and feed.
Used at about 3-4 hours after being created. Times vary on Hydration, Flour, and Temp.
Favors subtle lactic acid production (flavor similar to yogurt acidity)


Used at the later stages of yeast production.
Mixed with a 80% discard and feed.
Used at about 12-16 hours after being created. Times vary on Hydration, Flour, and Temp
Favors a more pronounced acetic acid (vinegar acidity) and less lactic acid flavor.

Any comments or help would be greatly appreciated,

Thank You,

Bake On.

ars pistorica's picture
ars pistorica

no. it is much more complicated than that! acetic acid production is more closely tied to fermentation quotient, and determined by starter conditions, redox potential, substrate type, temperature and fermentative conditions.

clazar123's picture

Terminology is often confusing and means different thing to different people and different geographic locations and languages. That said, I will tell you what I believe to be true in very simplistic terms because I am NOT an expert and simplistically is how I understand these  terms.I am not a production baker and if you need production information, I believe ars pistorica is the person to answer that kind of question. My experience is 2 loaves at a time, home kitchen baking.

A levain is used to raise a dough-it is usually something in the yeast family.

A culture is a collection of a growth of a living organisms-one species or many species. Not all cultures can raise a dough-some give us infections, some flavor our cheese,some make beer,some generate medicines, etc.

I have seen "young" used with "starter" and occasionally with "culture" but in regards to sourdough bread, I believe it to mean a relatively newly started starter/culture ( in the last few weeks) that may not yet have a true symbiotic collection of organisms andnot yet be truly sustainable, longterm. A "mature" starter or culture (if you prefer) is "older" -it was created a longer time ago and has had a chance to develop into a balanced,symbiotic collection of different microorganisms that will sustain themselves long term. It behaves consistently and predictably depending on the temperature,frequency of use,flour used for feeding and hydration. Its characterisitcs can be changed by varying any or all those factors but then it usually changes the species makeup or behaviour.

I have seen "young" and "mature" used to refer to preferments, also.It is a preferment that is in different stages of development prior to adding to a dough.

Many similar phrases-different situations. I hope I was helpful.





ars pistorica's picture
ars pistorica

I am putting together a how-to for home-bakers about starters.  Sorry for any technical language (please see my introduction), but everything I share on this site, along with anything I bake, was created for, and in, the same conditions as 99% of home-bakers on this forum.

A "young" starter, in most cases, simply means a levain in the early stages of development (in regards to metabolic and reproductive activity), usually in the grey area between the lag- and log-phases.  Many professional and/or experienced bakers use the term (also synonymous with "green," "immature," "not-yet-developed") to imply a starter that some bakers say "is just beginning to wake up."  Usually, if the dough-yield of the starter is low enough (say, less than < 175), there will be noticeable CO2 production as a result of the immediate processing of available food-sources (most food sources for yeasts and lactic-acid bacteria are bound up at this point, either awaiting enzymatic action and/or substrate availablility, or because there are simply not enough metabolites present), meaning the culture could be used for leavening.  But remember this:  most bakers are concerned with leavening; great bakers are concerned with fermentation.

The taste of bread comes from a well-fermented dough, not a well-leavened one, but a well-fermented dough should also thankfully produce a well-leavened one, too.  Or put another way, flavour in bread comes down to a series of complex interactions between starter microflora (yeasts and bacteria); and their metabolites; cereal substrates; and their enzymes and other enzymatic activity; and, lastly, the amount of free amino acids.  To increase flavour, one would increase all, or any one, of these things.  CO2 output can happen independently and before any of these other, flavour-related processes can occur.  Fermentation helps turn a raw dough into something more digestible, nutritious, preservable and tasty.  Leavening a dough simply fills up its empty, internal holes with CO2.  A "young" starter, then, would be one in its infancy, before any major metabolic or enzymatic activity has occurred.  Bakers only designate a starter's age when there is noticeable activity, i.e., usually after initial CO2 production, when he or she has observed that a convex-top has developed and there has been some noticeable growth.

A mature dough would be one that's well-fermented.  I'll let you be the judge of what that is, as it mostly comes down to personal preference (I'd recommend staying well shy of the stationary phase, when cell and amino-acid counts begin to fall, working against your bread).

Born2Bake's picture

You are a rockstar, that was very well done. As an Inspiring great baker, I cannot thank you enough. Looking forward to reading your session on sourdough. How can I make sure to get it as soon as it comes out?

I was experimenting with a 50% discard and feed with my culture and then building my levain after 2-4 hours, that sits for 16 hours.

I was also experimenting with using 20% discard and feed and let it sit for about 16 hours, then building my levain that sits for 16 hours.

So from the literature above the second, longer maturing 20% discard and feed should yeild more flavor from the grain?

Quote of 2013, and yes I know it just started. I can't wait to learn more from you.

"Most bakers are concerned with leavening; great bakers are concerned with fermentation."

Thank you all so much for your comments!

ars pistorica's picture
ars pistorica

I would love to answer your questions, but I do not quite understand the process you're describing.  It could be me.  It might be better if we are expressing the way your levain is built with a common language.  Let me explain how I look at it.

First, disregard water altogether.  It is important, but not in the way most bakers think.

Second, pay attention only to flour amounts.  For instance, if there are 250 grams of a mature, 100%-hydration starter, the only figure to be interested in at this point is the 125 grams of flour in the ripe starter.

Third, know that substrates (for our purposes, flour types) matter.  The wholer the grain, the greater end-amount of free amino acids, which basically means flavour.  Remember, we are culturing and maintaining very tiny organisms that have evolved to metabolically respond to whole grains, which means they are very effective at breaking down and then converting all or most of these cereal grains into something that is digestible, nutritious, preservable, and tasty.

Fourth, think in inoculation amounts.  This would be the amount of starter, expressed by flour-weight only (see above), you are transferring to new substrate types whenever you feed it.  E.g., a 15% inoculation for a starter refreshment maintained at 100% hydration would be 30 grams of the older, mature culture to be inoculated to 100 grams of flour and 100 grams of water.

Fifth, temperature matters.  Keep your starter at room temperature, at all times.  A difference of 1-degree Celsius can make all the difference:  25 degrees Celsius (slightly) favours acid-bacteria growth, while 26 degrees Celsius favours yeast, but after 29 degrees, lactic-acid bacterial growth picks back up.  The sweet spot is 20 - 28 degrees Celsius.

Sixth, do not be afraid of acetic acid.  It is that mythical, Spinal Tap-like knob that turns all other flavours in bread to 11.

Seventh, a baker has much more control over the dominant microflora culture or cultures present in her starter, as well as how that starter behaves.  Fermentation is just metabolism by another name; you are the one that gets to decide what, when, how and how much, and even if the culture eats.

Eight, understand that different methods of feeding (time, temperature, inoculation percentage, substrate type and condition, redox potential, and so on) can dramatically shift a dominant, years-stable culture.  When bakers or bread books recommend doing the same thing every day with your starter, there's a reason.

Ninth, forget time.  It has nothing to do with fermentation.  This also helps you develop your senses more.

Tenth, creating and maintaining a starter is easy.  I can teach anybody to arrive at a functioning starter within 48-hours anywhere in the world, using just water and flour.  Implication?  If you become enthused for several months, and then suddenly quit cold-turkey, just throw your starter away.  No big deal.  Seriously.  It only takes two days.  I often do it all the time.

Eleventh, trust yourself and your tastes rather than authority, especially bread books.  I own 'em all, including the stupidly expensive industrial cereal science ones, and there's a huge gap in understanding between the scientific-industrial community and a bread book ordered from Amazon.  Bigger than most forum members here perceive, which is to say:  what appears as authority isn't; it's just one perspective.

So, getting back on topic, at home, I maintain a 60%-hydrated starter, which is said to have a dough-yield, then, of 160 (flour percentage added to water percentage).  I feed it daily, using organic stone-ground whole-wheat, keep it at room temperature, and vary my inoculation amounts depending upon the projected ambient temperature curve of the day.  At the moment, I'm using a 6.5% inoculation, as it is summer where I am (albeit a cool summer).  My final dough temperature is always 22 - 25 degrees Celsius.

How do you keep yours?

Juergen Krauss's picture
Juergen Krauss

Hi Ars, your comments are quite inspiring, challenging at times. Especially your remarks about time sent my head spinning, ever since you first posted your views about the subject. Thanks for that.


ars pistorica's picture
ars pistorica

But remember that time does matter in that it's one variable that is very easy to control and predict.

Juergen Krauss's picture
Juergen Krauss

Ars, I have no doubt that time matters.

The question to ask is: Which time?

I think the major difficulty is to separate the "time percieved by the observer" from the "physical time elapsed in the system under consideration". Common language has no real way of dealing with this. (In order to understand what "observing" means it is useful to look at some of the works of Einstein, Bohr, Heisenberg etc. ) My view in brief: If I set a kitchen timer I switch my perception of time over to the ticks on the face of that timer, and give away all my powers. If I watch the dough I switch my perception to a "clock" associated with the fermentation process. This "clock" has as ticks on its face things like acidity, smell, taste, viscosity,... (you name it). I can then intervene when I deem it fit to suit my tastes and expectations.

ars pistorica's picture
ars pistorica

I think the major difficulty is to separate the "time percieved by the observer" from the "physical time elapsed in the system under consideration".

I did this years ago.  It is also, in part, one of the reasons why I believe the mass effect occurs.

ars pistorica's picture
ars pistorica

This "clock" has as ticks on its face things like acidity, smell, taste, viscosity,... (you name it).

This is also the reason starters should always be maintained at room temperature, and also why I recommend bulk fermentation at room temperature:  within a certain temperature range (20 - 28), all of these considerations are expressed to their most ideal (desirable) form and will all fall into place at the same time.

Born2Bake's picture

Life has been kinda crazy lately.

I keep my starter at 100% hydration, I have flour that is mixed 45% Unbleached White (King Arthur), 45% Whole Wheat, and 10% Whole Rye.

I keep the temp at 70-72 degrees fahrenheit - or about - 21, 22 C

I feed it every day at the same time.

I think I feed it at a 50% inoculation

I usually keep about 200g of mature starter and feed it with 100g of blend flour, 100g of filtered tap water (just to take out chlorine and fluoride) the water is about 100ppm. I read that 100-150 is great for bread and starters.

Right now im using this method in the following way.

10am feed the culture. I check development and see if it is active and smelling creamy and smooth, at this point is seems as if there is no acetic acid development (if there is its not detectable by smell) use it at 3-4 hours to build a unbleached white flour levain that will mature for about 16 hours and then be used to mix the final bread (Vermont Sourdough, from JH, Bread) ---

also how do I know if I need to build the levain with multiple builds? Just so the critters do not get overwhelmed and are unable to eat without being overly "taxed". I read that smaller meals help cultures build to a larger size without overwhelming, that being said I don't want to underwhelm them either..

Hope this makes sense,

Thanks mate.

Juergen Krauss's picture
Juergen Krauss


How are you doing?

There are a lot of good posts on this site about creating great starters.

You might want to look into ananda's blog,

or see dmsnyder's fantastic essays on SF Sourdough

I think as a home baker it is possible to be fairly relaxed about feeding cycles and storing in the fridge as long as the starter works and wakes up again after refridgerating. Keep it simple (and reproducable).

Rye sours and Wheat sours are very different, and there is a fair deal of cultural stuff around the way they are used and treated.

Happy baking, and I hope to hear more from you,