health benefits of natural starters

[artellan]

Norma asked on another thread, I thought I would split to here:

I would be interested in hearing the health benefits of using natural preferments.

Norma

Hi Norma

I'm not sure about other types of natural preferments, but sourdough has the following health benefits (as I understand it). I would suspect that most of them are true for other types of natural preferments as well.

1. Sourdough is a symbiotic culture of natural yeast species and lactobacillus (or lactic-acid-producing) bacteria. Many of the lactobacillus species commonly found in sourdough cultures are considered "probiotics" i.e. healthy gut flora. Now, with most uses of sourdough (bread, pizza) the yeast & bacteria will all be dead by the time you ingest it, so it has no probiotic effect. But, if you ever taste your starter, or make pancakes (mine are often pretty soft on the inside) you might be getting some probiotics.

2. Increased mineral absorption. Because there are so many different species of organisms involved in the fermentation, sourdough does a much better job of pre-digesting, and humans can absorb a lot more of the nutrients. For example, the bacteria in sourdough break down phytic acid in wheat which prevents mineral absorption. Because of this sourdough bread is actually a good source of iron.

3. Similar to above, sourdough also does a much better job of breaking down gliadin (the component of gluten that causes problems in people with gluten sensitivity) than commercial yeast. While fully gluten intolerant people (celiac disease) still can't have wheat-based sourdough, it may be okay for those with a minor sensitivity. And my opinion is that eating sourdough in place of commercially-yeasted bread, will make you less likely to developer gluten sensitivity later in life.

4. Sourdough products have much lower glycemic index (I've heard 68 for white sourdough compared to 100 for regular white bread). This is especially important for diabetics, but probably matters for everyone (give your poor pancreas a rest!). See here for a scientific study: http://www.uoguelph.ca/news/2008/07/sourdough_bread.html

Some of the above benefits can probably also be realized by using longer fermentation times with commercial yeast, like we see in many of the pizza recipes on this forum. (It's kind of neat that the reception of "better taste" with long fermentation goes hand in hand with health benefits.) But, I would guess that sourdough still has a big advantage over commercial yeast, because of the lactobacillus bacteria, and having multiple varieties of yeast, it can do a more thorough job of fermentation.

Cheers, and sorry if it sounds like I'm on a high horse!
Mike

[norma427]

Mike,

Thanks for your in-depth post.    I never knew sourdough did so much in fermentation and all the other things you posted.  I find it interesting about the health benefits of sourdough. 

When I first decided to try milk kefir as a leavening agent, this was one of the articles I read about the benefits of using milk kefir grains.  http://www.kefir.org/kefir_manual.htm  I had thought after the bake, the milk kefir added for leavening would be dead and no additional benefits would be derived from using the milk kefir, but I guess after what you posted about using sourdough, there are some health benefits even with using milk keifr.  I have also just started to see some benefits from adding dairy whey to some of my doughs, but they aren’t health benefits.

Norma

[dellavecchia]

Mike - Excellent information, thank you for the post. A number of us have been baking the Tartine country sourdough in another thread. Would you care to post about your sourdough recipe and workflow?

John

[buceriasdon]

Ah so. Natural starters in pizza with kimchi make for very good food.   http://www.health.com/health/article/0,,20410300,00.html
Oi!

[foolishpoolish]

Ah so. Natural starters in pizza with kimchi make for very good food.   http://www.health.com/health/article/0,,20410300,00.html
Oi!

Kimchi pizza...now there's an idea for the February pizza theme...

Interestingly (or boringly...depending on your POV) some of the strains of bacteria responsible for the fermentation in Kimchi are of the Leuconostoc variety and considered to be undesirable in Sourdough and are attributed to the "stink" in some of the methods of initiating a starter culture. However, I have started to change my opinion on the role of Leuconostoc in sourdough, as apparently some strains have been found in significant number in Panettone dough (which is far from stinky!). I suspect  more likely culprits are certain strains of Enterobacter...but that's just speculation.

FWIW Leuconostoc and Lactobacilli BOTH fall under the umbrella of lactic acid bacteria (LAB for short).

[Pete-zza]

Mike,

Sourdough breads have anti-staling characteristics that extend the shelf life of the breads and, if the doughs are fermented for long periods, as they usually are, then the final breads can be more readily digested.

On the flip side of the coin, have you seen any research on the carbo-loading aspects of sourdough breads? We have a lot of members who make a lot of breads, both sourdough and non-sourdough, along with quite a few pizzas, with the bulk of these being made from refined flours. The same people may also be eating a lot of pasta, also based on refined flours. I would think that at some point too much unrefined carbohydrates may be consumed. I also heard a public radio interview yesterday morning where a physician, who is an endocrinologist and childhood obesity specialist, said that people on average get around 150 pounds of sugar a year in their diet. I think that that may have been only through processed foods but I may be wrong on that. But I recall when that figure was 50 pounds. No doubt that was before food processors started adding more sugars (in all forms) to foods in lieu of fats when people started balking about all of the fats in processed foods. I would think that all of the refined carbohydrates being consumed would make the Islets of Langerhans (pancreas) work overtime producing insulin, as well as taxing the liver, which apparently processes fructose, which is increasingly used in processed foods. Maybe a high carbohydrate diet is better than a high fat diet, but swapping out one type of potential disease for another doesn't sound particularly appealing to me.

Peter

[dellavecchia]

Although the glycemic index of sourdough may be 68, which can be debated (and the index itself is debatable), all grains, refined or not, spike your insulin. If most of your diet is carbs, such as grains, beans, sugar, etc, some say it can lead to insulin resistance and ultimately metabolic syndrome (which includes diabetes).

Due to a health condition, I am on a "low carb" diet. My diet is mainly good fats, lean protein, vegetables, nuts, fruits, and fish. I also do intermittent fasting 2-3 days a week, which means I do not eat from dinner to dinner the next day and only consume water. I obviously cheat with pizza, pasta, and bread, but I try and stick to an 80/20% rule - 80 percent of the time I am on the diet, the other 20 is spent consuming things I really enjoy. My doctor is not happy about that, but I seem to be fine for now.

John

[artellan]

Peter and John,

I agree that too much unrefined carbohydrates can certainly be a problem. I think 'everything in moderation' is a good way to live (of course subject to any health issues which must be considered first). So yeah, naturally leavened may be healthier than commercially-yeasted, and homemade anything is often healthier than store-bought. But you still have to be conscious of what you are consuming and pay attention to your body ... I find if I eat a lot of pizza then I don't want bread/toast as much the next day etc.

Note: while I do bake and eat a lot of bread, I give a lot of loaves away too! And I usually only make pizza when we have company...

Peter you mentioned the keeping quality of sourdough, and I've definitely noticed that in my sourdough breads. There's a funny story in Hamelman's Bread where he talks about making 90% rye sourdough as part of his food supply for a 5-6 week backpacking trip. He says even 5 weeks later the last loaf (cached for 5 weeks outdoor in summertime) was still good. Of course 90% rye will keep much better than wheat breads, but still that is amazing!

Cheers
Mike

[artellan]

Mike - Excellent information, thank you for the post. A number of us have been baking the Tartine country sourdough in another thread. Would you care to post about your sourdough recipe and workflow?

John

Hi John
Sorry for my slow response ... I'd love to post about my sourdough. I'll start a new thread about it when I get time (been really busy lately).

That Tartine rustic country sourdough looks amazing, I hadn't heard of that book before, so thanks for the tip! I've put it on my birthday 'wish list'.

Cheers and happy baking
Mike