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Sourdough Bread

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RyanX:
I couldn't find anything on this forum concerning the craft of sourdough bread making, so I thought I'd create this thread.

My brother got me interested in sourdough breads a few years back.  I had already started making my own bread from scratch ingredients after becoming thoroughly dissatisfied with the packaged breads in the supermarkets.  One day he gave me a small jar of the sourdough starter and I was off on my new adventure!

A sourdough starter to the uninitiated is just a mixture of flour and water.  The proportions of flour to water vary depending on the type of bread or baking technique in question.  In reality, the sourdough starter is actually a whole zoo of microorganisms. 

_http://en.wikipedia.org/wiki/Sourdough


--- Quote from: wikipedia ---A sourdough starter is a stable symbiotic culture of bacteria and yeast present in a mixture of flour and water. The yeasts Candida milleri or Saccharomyces exiguus usually populate sourdough cultures symbiotically with Lactobacillus sanfranciscensis.[1]. Lactobacillus sanfranciscensis (bacteria) was named for its discovery in San Francisco sourdough starters.
--- End quote ---

My understanding is that the reason why a sourdough starter can persist (indefinitely?) with proper care is due to the symbiotic relationship of the yeasts and bacteria.  I won't pretend I understand all the chemistry and biology involved here, all I'm concerned about is that it works.  It really does leaven bread, although not in quite the same was as the instant dry yeasts. 

The key to sourdough breads is "starting" them.  If one is really interested in starting their own sourdough, be prepared for a few trials before actually getting to the real deal.  Otherwise, there are internet shops where one can purchase a freeze-dried sourdough culture that is ready to go.  If you're looking for more or less instant gratification, I would choose the purchasing option.  If you're at all interested in trying to culture the yeasts/bacteria from your environment, I will attempt to describe this process.

To start a culture, one must put out a bowl (preferably a wide bowl) of a flour and water mixture.  The ratio I like to use is 3/4C water per 1C flour.  Most advise I've read says to use unchlorinated water due to the chlorine's anti-bacterial properties.  Some advise against using city water altogether.  I have a large carbon and KDF filter on my home water supply and I've found this sufficient.  My brother says he likes to use bottled water.  I would give your culture whatever water you're used to drinking.  If you can't culture sourdough using the water you drink, you might want to consider what that water is doing to the inside of your body.

In any case, you'll want to start with a bowl of 3C flour and 2.25C of water.  Set this out in an open area and cover it with a clean towel to keep dust and insects out.  Stir this mixture a few times a day, ever day until you notice a distinct rise and sour odor coming from the bowl.  Also, you will have to throw out half the dough/water mixture each day and replace this same amount with new flour and water.  This is important as it gives the yeast and bacteria new food to multiply on.  If you start to see discolorations or signs of mold, throw it out immediately and start over with a clean bowl.  If this happens you, you've either cultured something bad, added too much water or too much flour, or not changed the starter regularly enough.  It might take a few days to start a culture, or it may take weeks.  Be patient and remember the steps I've given above.

If you're still having trouble starting the culture, I have read that adding a mashed, baked potato at the beginning will help, although I've never tried this.  I've also heard of people adding a small amount of whey from raw milk to start the bacteria side of the culture.  I'm not sure what, if any validity is behind any of these tips. 

The time of year also seems important in regards to starting your sourdough culture, although I've read little elsewhere about this.  I've had little luck culturing sourdough from the air during the winter months.  At least in my area (Wisconsin, US) there seems to be something missing in the air during this time.  I've had most of my success during the summer and autumn months culturing sourdough.  The good thing is that if you're careful you should only have to start the culture once.

I've mentioned water, but I also want to mention flour.  Flour quality can be almost as important, if not more important than water quality.  Unfortunately, we probably know less about the quality of flour that we purchase than the quality of water we drink.  I spent a good deal of time researching how flour is produced awhile back, this seemed to be the best description of the flour making process I could find online:

_http://books.google.com/books?id=oCVPjK0mSfkC&pg=PA59&lpg=PA59


--- Quote ---Milling converts grain into flour.  Grinding grain between two stones is a process of great antiquity.  Pairs of hand operated stones known as quorns have been found among the relics of some of the earliest agrarian settlements.  Using water power to drive a pair of stones must have made for a much easier life.  Driving the stones by wind power as a windmill is a later development introduced into Europe as a consequence of the crusades.  A later innovation was the roller mill.  In this system the wheat berry is dismantled layer by later.  In a stone mill the wheat berry is simply crushed, which produces a wholemeal flour - any other type of flour can only be made by performing a separation on the flour.

In a roller mill wholemeal flour can only be made by recombining all the fractions at the bottom of the mill.  This is why some wholemeal flour is still stone ground.  The stone mills used are not antiques but are usually driven by electricity.  There is no reason why roller mills or stone mills should not be driven by water power in the form of a water turbine.

The important point for the baker is that milling affects the flour in ways that cannot be altered elsewhere in the process.  The most important effect is the amount of starch damage produced in the milling process.  Damaged starch can absorb water while undamaged starch can not.  Because damaged starch can be attacked by amylase enzymes it is a source of food for the yeast.  The action of amylase enzymes on damaged starch softens the dough.  While this may be desireable in some products, if it goes too far the dough will become sticky and unhandleable.  In bread flours based on hard wheat a high degree of starch damage is desirable since it allows a greater yield of bread as the starch absorbs water.  Excessive amounts of starch damage lower bread quality.  In some soft wheat flours, as used in biscuits, low starch damage is desirable.  After the milling process, any gaseous treatments are applied, any powder treatments, e.g. ascorbic acid, are added as well as any fortifying ingredients such as calcium sulfate.  Different countries have various polices on fortifying flour.  In the UK, white flour is fortified with calcium to make up for the calcium lost by not making a wholemeal flour.  In the US, bread is fortified with folic acid.  It is possible for an untreated flour to be mixed with a flour improver containing the powder treatments. 

One property of the flour that is controlled by the miller is the extraction rate.  Wholemeal flour has a 100% extraction rate, with brown, white and patent white having progressively reduced extraction rates.  One obvious difference is the flour.  Another is that the quality of the protein increase towards the middle of the wheat berry from the patent flour is produced.  Thus patent flour is sometimes used not to produce whiter bread but in products like filo pasty or West Indian patties where the strength that patent flour gives is important and the colour is irrelevant.

--- End quote ---

So as you can see there is a lot of room for variation and experimentation in the types of commercial flours produced.  Unfortunately the marketing literature on these flours usually tells us next to nothing about what types of wheat berries were used, how they were processed and what additives or other post milling treatments were used on the flour.  Flour regulations differ from country to country as well. 

In regards to sourdough, I will say that I have killed my culture by switching to a different flour.  I went from what I believe was a "brown flour" (or a roller milled flour with some percentage of bran added to the starch) to a completely "white flour", which had no bran and a list of other additives and fortifying agents.  I did this when I was in a pinch for flour and needed to feed my culture.  Unfortunately, the end result was me starting over again from scratch with my culture.  Other people I've talked have had similar dealings with changing flours and others have had no problems at all switching flours.  From what I've read, it should be possible to start a sourdough culture on any type of flour, but I would caution making big changes to the flour you feed your culture.  Bottom line, be consistent if that is possible in feeding your culture.  This has just been my personal experience. 

If you find that your culture is seems dead (i.e. doesn't rise when fed), there are a couple of things to try.  Take a small portion (maybe 1/4 to 1/2 cup) of the dead culture and reattempt to "start" this by adding the 3C of flour and 2.25C of water.  Throw out half of this mixture every day and add back fresh flour and water to keep it fed.  Do this until you notice a significant rise in the starter again. 

If you're like most people, you might make bread once or twice a week.  You can save your culture in the refrigerator on the off days.  At refrigeration temperatures, you should only have to feed your sourdough culture once per week.  I will mention though, that you may want to take your culture out a day or two prior to using it and feed it a couple of times at room temperature.  During this time, you don't have to throw away the excess starter (unless you have too much or just want to).  Just keep feeding it small portions until it is well active.  At this point it should be ready for any leavening task at hand.

I typically keep my sourdough culture in a wide bowl and covered with a towel in the refrigerator when I'm not using it.  I switch bowls maybe once every two weeks or so.  If you don't clean out the bowl from time to time, it will form a hard crust at the "high tide" point where the sourdough rises to and falls back down. 

Also, DO NOT, under any circumstances try adding commercial yeast to your culture to get it "bubbling".  I've killed a culture doing this.  I'm not sure why, but I would hypothesize that the instant yeast will diminish all the food available for the natural yeasts, leaving them with nothing in the end.  Commercial yeasts do not persist and form a symbiotic relationship with the bacteria.  If you want to give your bread a "boost", feel free to add this at the point of bread making, but never add this to the starter itself.

Sourdough can be used in a lot of recipes besides breads.  I've personally used it to make:

Muffins,
Pancakes (these are really tasty!),
English Muffins,
Bagels,
Hamburger buns,
Pizza crust,
Crackers

I've gleaned most of these recipes from the book Classic Sourdough:

_http://www.amazon.com/Classic-Sourdoughs-Home-Bakers-Handbook/dp/1580083447

I would also recommend this website for sourdough tips and recipes.  It is somewhat commercial, but the owner does give very sound advise:

_http://www.breadtopia.com/

Here is my basic sourdough bread recipe (2 loaves):

On the eve of baking, mix a bowl of 2C of sourdough starter, 1.75C water and 2C of flour (any type of wheat or white flour will do)
Also stir in 1tsp of salt at this point.
Let this sit in a covered bowl at room temp until the next morning.

Make sure you have at least 1C of sourdough culture left over to continue the culture.  Use this time to feed the culture new flour/water and set aside for the next use.

Next morning:

1/3C lard or coconut oil or butter (make sure these are melted before adding)
3 tbsp of sugar or honey

Add these to the frothy culture that was started the night before and mix thoroughly.

Add 1 C of flour at a time until the dough becomes unstirable and transfer to a slightly floured surface for kneading.  Usually I end up adding a total of 5C of flour to the finished product.  The more you make the recipe the more you'll be able to "feel" when enough flour is added.

Kneed this for 1/2 hour and transfer the dough ball to a covered bowl and let sit for 1 hour.

After 1 hour, the dough should have risen somewhat.  At this point either shape the dough or transfer it to the desired (greased) pan and let sit for another 3 hours.  This recipe makes about 2 loaves.  Sourdough tends to take longer to rise.  This is normal.  If it takes over 3 hours to rise, the culture might not be fully active or it might be sick in some way.  Refer above on how to revive a dead or dying culture.

Cut a few vents in the bread and back @ 375 degrees for 45 minutes.  That's all there is to it!

As far as health goes, I realize a lot of people have concerns about Candida.  Now, from what I understand one of the common yeast strains in sourdough bread is candida yeast!  On the other hand, this yeast is somewhat tempered by the lactobacillus bacteria living in the culture.  From what I've read, some believe that this bacteria is what takes the wheat flour, which in raw form is essentially a poison, and turns it into a somewhat more digestible product.  The action of the bacteria is said to reduce the phyto-chemicals and gluten content of the yeast as well as add a number of amino acids to the mixture.  I'm uncertain what role the yeast play other than perhaps food for the bacteria and visa-versa.  Consider this study below:

_http://www.uoguelph.ca/news/2008/07/sourdough_bread.html


--- Quote ---Not all bread is created equal. The type of toast you eat for breakfast can affect how your body responds to lunch, a University of Guelph researcher has discovered.

Prof. Terry Graham studied four types of breads to determine which had the most positive health effects when it comes to carbohydrate metabolism, blood sugar and insulin levels.

"There's an urban myth that if you want to lose weight, you shouldn't eat bread," said the human health and nutritional sciences professor. "But the truth is, bread is one of our biggest sources of grains and has a number of healthy benefits. With this study we wanted to find out which breads are better so that we can optimize the benefits by combining them into one type of bread."

Using white, whole wheat, whole wheat with barley and sourdough white breads, Graham and a team of researchers examined how subjects responded just hours after eating the bread for breakfast and again just hours after eating a standard lunch.

The subjects, who were overweight and ranged between 50 and 60 years of age, showed the most positive body responses after eating sourdough white bread, and those positive responses remained even after eating a second meal that didn't include bread.

"With the sourdough, the subjects' blood sugar levels were lower for a similar rise in blood insulin," said Graham, whose findings are to be published in the British Journal of Nutrition. "What was even more interesting was that this positive effect remained during their second meal and lasted even hours after. This shows that what you have for breakfast influences how your body will respond to lunch."

He said it's likely that the fermentation of the sourdough changes the nature of the starches in the bread, creating a more beneficial bread.

And while sourdough came out on top, the whole wheat varieties used in the study came out on bottom - even below white bread.

The whole wheat breads caused blood sugar levels to spike, and these high levels lasted well after lunch.

...
--- End quote ---

It has also claimed that some people with gluten sensitivities are able to tolerate sourdough bread. 

_http://www.denvernaturopathic.com/news/sourdough.html


--- Quote ---...

During these last hundred years, celiac disease has appeared in our medical texts. Of course, it may have been around much longer, but curiously, there is little mention of it. Celiac disease was first described accurately in the early 1950s by Dr. Willem Karel Dicke, a Dutch pediatrician, who recognized that the disease is caused by the ingestion of wheat proteins. This disease appears to be getting more common. My old Merck Manual from the mid 1980's put the incidence at about 1 in 1200 people. A recent bakery trade journal puts the incidence at about 1 in 50. This increased incidence may simply be greater awareness and a greater likelihood of recognition. Yet one has to wonder.

There is a fascinating paper on sourdough and celiac disease. Italian and Irish researchers have found that some lactobacilli bacteria in sourdough can digest and modify the gluten proteins in flour to the extent that a person with celiac disease may be able to eat them without ill effect.

Rafaella di Cagno and her colleagues set out to produce a bread well tolerated by people with celiac disease. They selected specific sourdough bacteria that were especially good at breaking down the chemical bonds in wheat gluten that trigger the celiac immune reaction in people with the disease. They were able to show experimentally that fermentation with these specific lactobacilli completely inactivated the particular peptides that cause the reactions. The researchers then baked sourdough breads using a mixture of wheat, oat, millet, and buckwheat flours. After 24 hours of fermentation, wheat gliadins were almost totally broken down. When tested they had less than 1/250 the action of proteins from bread dough made with baker's yeast.

The researchers then baked two types of bread, one made with baker's yeast and the other with this special lactobacilli bacteria. The researcher fed their bread in a double-blinded fashion to 17 patients with celiac disease. Thirteen of the 17 patients showed a “marked alteration of intestinal permeability after ingestion of baker's yeast bread.” That is a fancy way of saying it messed up their guts. However, when fed the sourdough bread, the same 13 patients had no measurable changes in their gut permeability. In other words, the sourdough bread didn't bother them.

“These results showed that a bread biotechnology that uses selected lactobacilli, nontoxic flours, and a long fermentation time is a novel tool for decreasing the level of gluten intolerance in humans.”

This information of course raises the question whether part of the increased incidence in celiac disease is just the result of the decreased use of sourdoughs to bake bread. Replacing sourdough with commercial yeast probably has increased the exposure of people to celiac triggering proteins that now remain undigested.

...
--- End quote ---

To me, the taste of sourdough is unbeatable and this is the main reason why I do it.  Next to that, I like the fact that there is one less ingredient (instant dry yeast) that I must purchase to make bread.  I've never had any known problems with digesting gluten, but I have noticed that I feel less "full" after eating sourdough versus other bread types.  Anyways, I hope this is of use to somebody.

Enjoy!

anart:
Well, RyanX, since gluten is evil  - have you tried making a sourdough bread using other types of flour?  Even those without 'gluten sensitivity' or celiac's disease, greatly benefit from removing gluten from the diet.  There is more information on that in the diet and health section. I'd be much less concerned with the yeast in the bread than the gluten - so - it might be worthwhile for you to experiment with gluten free flours to come up with the perfect sourdough for those of us who are gluten-free!

RyanX:
I have tried using other flours, but they have all been gluten based flours.  Spelt, triticale, kamut, oats;  All of these are essentially wheat.

I have heard of people using a combination of rice, tapioca, potato and coconut flours as a gluten free substitute for the standard wheat-based flours.  My guess is that to keep any larger bread from falling apart, you would have to add eggs to it.  How many, I'm not sure.  If I get the chance I'll try some experiments.

Sourdough itself is pretty non-specific as far as flours go.  Like I mentioned, changing from one flour to another can be problematic, but in theory any flour should do, gluten-based or not.  I believe it is the starches that the micro-organisms feed off of, which can come from just about any flour.

_http://gingerlemongirl.blogspot.com/2008/08/hide-and-seek-tweaking-gluten-free.html - This looks like a good start.

Edit:  Since I mentioned eggs, you can use these to cut down the kneading time in any bread recipe.  I used to do this some times.  The whole purpose of kneading the bread it to develop the gluten - which is sometimes a time-consuming process.  The gluten is essentially what gives bread it's stretchiness and elasticity.

Johnno:
Thankyou for that Ryan, seems you've done your homework. I never knew that the culture was used by using the flour itself, utilising the yeasts in the atmosphere. I was reading up on cheese making and they use much the same technique to get them "ripe", natural spores in a certain cave or geographical location give rise to diffeent sorts of cheeses. There's more spores around in the warmer months which could explain the difficulties in winter.

I'm going to try it with some gluten free flour.

Laura:
Yup, I think the whole world would be better off if gluten disappeared from the planet!   Some people CAN tolerate it, but it can't be doing them any good since the gluten proteins bind to the opiate receptors in the gut (and elsewhere, I think).  It's an addiction, pure and simple, and not a good one.

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