Showing posts with label fermented. Show all posts
Showing posts with label fermented. Show all posts

Wednesday, February 16, 2011

Get Over Fear of Bacteria: Fermentation Primer

Fun with fungi and bacteria. 
In my last post I mentioned how I had been experimenting with some home fermentation techniques. Well it took a little while, but the ball is really rolling on this now. I just tried a bottle of the latest elixir... Wow! It inspired me to sit down and type this out right now.


Some gooood stuff. 
Here's a brief explanation of  what fermentation is, its history, and benefits.

What is fermentation?
Fermentation is when microorganisms eat a carbohydrate, usually sugar, and release byproducts such as ethanol, lactic acid, and carbon dioxide. Basically you feed bacteria or yeast (fungi) sugar and they produce copious amounts of alcohol, CO2, and lactic acid. This results in a well preserved and usually bubbly (and sometimes alcoholic) food or drink. Think of fermentation as bacteria predigesting food to make nutrients more available for absorption.

History of fermentation.
Fermentation has been occurring in nature for longer than humans have been on the planet; in fact it's a vital process in the cycling of nutrients through the food chain that makes life possible.

The earliest evidence of humans controlling the fermentation process is wine-making about 8,000 years ago in the country of Georgia [1].


The first alcoholic society. Just kidding.
Iran, Babylon, Egypt, Sudan, and Mexico all were using fermentation techniques thousands of years ago and nearly every indigenous culture has developed some type of fermentation techniques. But why is it that fermentation has been sought out by so many different societies?

What kinds of food are fermented?
Here's a small sampling of foods that are dependent on the action of bacteria and yeasts.
  • Alcoholic beverages: Wine, Beer, Liquors, Mead
  • Lacto-fermented vegetables: Sauerkraut, Kimchi
  • Fermented dairy products: Yogurt, kefir, cultured milk, cheese
  • Bread: Such as sourdough (CO2 gas from bacteria causes bread to rise)
  • Fermented teas: Kombucha
  • Water kefir
  • Beet/bread kvass
  • Fermented soy: Miso and tempeh
  • Cured meats: sausages, salami, etc.
  • Other meats: rotten fish in the ground (yum!)
  • Poi - fermented Taro root
  • Fermented cassava
  • Many types of fermented grains and legumes.

Benefits of fermentation.
Although there are probably a lot of things I'm missing, fermentation seems to be generally used for these reasons:
  1. Adds a diversity of textures, flavors, and smells to foods.
    • Fermented foods taste awesome, but are definitely an acquired taste. 
  2. Preserving foods to last a long time without refrigeration.
    • Using bacteria or yeasts to convert carbohydrates in to alcohol, lactic acid, and acetic acid dramatically increase the amount of time that foods can go without spoiling. Before refrigerators, this is what everyone had to use.
    • For example lacto-fermentation creates lactic acid, a natural preservative that inhibits the growth of putrefying bacteria. 
  3. Improves nutrients available in foods.
    • Fermentation dramatically increases the availability of nutrients such as vitamins, minerals, and amino acids through a variety of mechanisms. Bacteria predigest foods and make them available for us to absorb. This really deserves an article of its own.
    • Fermentation creates Vitamin K2, an extremely important nutrient that nearly everyone is deficient in.
  4. Gets rid of anti-nutrients.
    • Double star this one- this is really important. A main part of ancestral nutrition is to not eat the anti-nutrients that are present in grains and legumes such as phytic acid, lectins, and other proteins. 
    • Fermentation breaks down phytic acid, destroys lectins, and can eliminate other problematic proteins. This is why it's so important to properly prepare grains and legumes if you are going to eat them.
  5. Decreases cooking time and uses less fuel.
    • This isn't so important in the modern world, but if you had limited amount of time and fuel this could be a big benefit. 
  6. Indirect benefits- Probiotic Bacteria:
    • Double star this one too, probiotic bacteria deserve an article of their own. In short, humans depend on the bacteria in our guts for a huge range of physiologic functions. With our industrial diets, good bacteria are often forced out and putrefying bacteria take over the gut which leads to a wide variety of nasty problems. 
So here's what some experts say on fermented foods:

Chris Kresser - The Healthy Skeptic:

"Almost all healthy, traditional cultures that have been studied regularly consume fermented foods like yogurt, kefir, sauerkraut, kim chi and kombucha. These foods have numerous health benefits, but in the context of heart disease one of the most important reasons to include them in the diet is that they are one of the few dietary sources of vitamin K2.  
...A 1993 study showed that those in the highest third of vitamin K2 intake were 52 percent less likely to develop severe calcification of the arteries, 41 percent less likely to develop heart disease, and 57 percent less likely to die from it."
"Probiotics found in fermented foods like yogurt, kefir, sauerkraut and kimchi strengthen and maintain the mucosal barrier system (in our respiratory and intestinal tract), which is our first line of defense against pathogens. What’s more, 75% of our immune system if found in the gut."
 Stephen Guyenet - Whole Health Source
"Healthy grain-based African cultures typically soaked, ground and fermented their grains before cooking, creating a sour porridge that's nutritionally superior to unfermented grains. The bran was removed from corn and millet during processing, if possible. Legumes were always soaked prior to cooking.

These traditional food processing techniques have a very important effect on grains and legumes that brings them closer in line with the "paleolithic" foods our bodies are designed to digest. They reduce or eliminate toxins such as lectins and tannins, greatly reduce anti-nutrients such as phytic acid and protease inhibitors, and improve vitamin content and amino acid profile. Fermentation is particularly effective in this regard. One has to wonder how long it took the first agriculturalists to discover fermentation, and whether poor food preparation techniques or the exclusion of animal foods could account for their poor health."
Good resources from Stephen:


Chris Masterjohn - The Daily Lipid
"Vitamin K2 is abundant in grass-fed animal fats and fermented foods, and promotes broad facial structure, healthy bones and teeth, a properly functioning nervous system, and robust cardiovascular health.
An accumulating body of research suggests that vitamin K2 may also protect against cancer."
 Robb Wolf - Paleo Solution
"The roles these bacteria play are varied, but they are critical in not only the digestive process, but also in actually protecting the gut lining. Our beneficial flora (the living mass of bacteria in our intestines) actually line the villi and microvilli in such a tight association that the bacteria are literally the first layer of our intestines. These bacteria displace potentially pathogenic bacteria, yeast,k and parasites; help us to digest macronutrients; and are responsible for production of various vitamins from precursor molecules.
...Most people are familiar with various fermented foods such as yogurt, kiefer, miso, kimchi, and raw sauerkraut. All of these foods (if not pasteurized) provide live cultures of beneficial bacteria."
Mark Sisson - Mark's Daily Apple

"[F]ermentation can render previously inedible or even dangerous foods edible and somewhat nutritious. The lectins, gluten, and phytates in grains, for example, can be greatly reduced by fermentation. I don’t advocate the consumption of bread, but if you’re going to treat yourself to any gluten grain-derived food, make real, long-fermented sourdough bread the one. The Romans managed to do okay on the stuff, but that’s only because meat was expensive and didn’t travel as well. Real sourdough is a good choice for guests who simply must have their bread, but don’t think fermentation makes it Primal approved.
Dairy is another beneficiary of fermentation. In fact, next to no dairy at all, I put fermented, raw, grass-fed dairy as the optimum form. The fermentation process breaks down the lactose, thus mitigating a potentially problematic sugar and decreasing the carb content (you can consider the official carb count of real yogurt cut in half; producers list the number of carbs present in the dairy before fermentation, and the fermentation process breaks down the lactose/sugar)." 


Wrap up.
Fermented foods is fun to make and has numerous health benefits. Stay tuned for part 2 where I'll show you what I've been making.

What kind of fermented foods do you like? Leave a comment with your thoughts.

Wednesday, February 2, 2011

Healthy Home Economist, My Fermented Food Adventures

Bringing it back.
I apologize for the hiatus- my last semester of school just started and time is stretched pretty thin between 17 units of class, track & field season, getting a business going, and applying for internships and grad school. Exciting stuff, but had to push the blog to the side for a while. Now that things are starting to even out I've got some good stuff coming down the line.

Healthy Home Economist.
In my internet travels I recently came across Sarah's blog 'The Healthy Home Economist', and I have to admit I'm very impressed. Her views on nutrition are pretty aligned with the Weston A. Price Foundation (A good thing- check out their site if you haven't).

After reading a couple of articles I went through several months of archives reading articles and watching her videos (which are excellent). Sarah covers a variety of topics from nutrition, environmental pollutants, medicine, food politics, exercise, and has several great videos how to do the stuff yourself. Sarah obviously follows her own advice, she is in amazing shape for a 40-something mother of 3 (but who's counting, right?).

My favorite parts of her site are the videos showing how to make fermented foods. A lot of these recipes are from Nourishing Traditions, one of my top nutrition and recipe books, but the recipes are far easier after you watch the process in a video.

In case you don't know, fermented foods are incredibly important for a variety of reasons that I will cover in depth in future posts such as repopulating intestinal bacteria, displacing bad bacteria, neutralizing plant toxins and more. They are one of the main things that modern people (Americans especially) are severely lacking in our diet.

Here are some of my favorite food videos so far:

Kombucha:

Kefir:

Beet Kvass:

And here are some of my other favorite articles:

Great work Sarah, keep it up.