Probiotics and Fermented Foods
Fermented foods have been a part of people’s diets all around the world for many centuries: yogurt, fermented vegetables such as sauerkraut and kimchi, natto, kefir, tempeh, miso, kombucha, and many foods that used to be preserved by natural fermentation such as pickles, cheese, apple cider vinegar, fish, buttermilk and sour cream. Many fermented foods contain beneficial bacteria, also called probiotics.
The community of beneficial bacteria that lives in our intestinal tract is called our “microbiome”. Recent research is showing that these bacteria (that are also found in other mucous membranes and on skin) serve more functions than we have been aware of. We have known for a long time that our microbiome is comprised of 10 times more cells than are found in the rest of our body and that they are important contributors to gut health. In fact, without them we would die. We are learning that there are thousands of different beneficial bacteria and that the microbiome of an infant is mighty different from that of a senior; that of a vegan is different from a meat-eater and that certain of our bacteria can work to keep specific health problems at bay. New research has shown that our mental development and well being is also connected to the health of our guts and that the microbiome plays an integral part in a bidirectional communication that goes on between the gut and the brain.
The microbiome’s functions:
1. It enhances nutrient absorption. Minerals and amino acids from protein foods and foods that are hard to digest such as milk products are all more bio-available in fermented foods or with the right bacteria in your gut. For instance, the phytic acid content in soybeans, which interferes with the body’s uptake of minerals, is greatly lowered by fermenting those soybeans.
2. Beneficial bacteria actually manufacture some very important nutrients such as B-vitamins, vitamin K, antioxidants and amino acids.
3. A healthy microbiome produces chemicals that protect us from invading pathogens, whether they be viruses, bacteria, fungi, molds, protozoa or parasites. Probiotics are an important part of our immune system….our first line of defence. They stimulate antibody and white blood cell production. According the Dr. Natasha Campbell-McBride M.D. in her excellent book “Gut and Psychology Syndrome” (available at most public libraries) 80-85% of a person’s immunity is located in the gut wall!
4. Ideally, a well-stocked digestive tract contains bacteria that are busy preventing cancer by neutralizing nitrates, and other toxic substances, chelating (removing) heavy metals and absorbing carcinogens.
5. Our microbiome protects the lining of the walls of our intestines and prevents holes from developing between the cells of that lining. If holes form they can enlarge, creating a “leaky gut” that allows large food molecules to pass directly into the bloodstream where they should not be. These food molecules are seen by the body as “foreign invaders” and so it dutifully produces antibodies to them. Problems arise because many of these food molecules are similar in structure to our own body’s molecules so eventually these antibodies can begin to attack friendly and useful parts of the body such as joints, pancreases, skin and thyroid glands, creating what we call “autoimmune diseases”. Ridding the diet of the offending foods, healing the gut lining and repopulating the microbiome have helped many people recover from autoimmune problems.
6. We are used to thinking of neurotransmitters such as serotonin and dopamine as being located in the brain, but it turns out there are more neurotransmitters in the gut than in the brain. The gut is loaded with neurotransmitter receptors that chemically signal the brain.
How is our microbiome formed:
We have none when we are in utero. We get our main implantation of beneficial bacteria as we pass thru the birth canal, assuming we do and that it is well-colonized. Further beneficial bacteria are transmitted through breast milk and by consuming fermented foods. Children born by Caesarian are not properly “colonized” at birth. And if they are not breast fed they can become quite vulnerable to developmental problems, illnesses and allergies. There are special probiotic supplements for infants who have missed getting them from their mothers.
Things that can destroy the microbiome:
Antibiotics, steroid medication, chemotherapy, birth control pills, painkillers, antacids, dietary chemicals, a diet high in sugar and/or alcohol, food intolerances, Splenda, chlorine, infection, too much stress and food sprayed with glyphosate (designed to kill bacteria, including ours) all destroy the microbiome. Many of these things did not exist 100 years ago. If we have been poorly colonized or have consistently used even one of the above listed microbiome antagonists we can create a situation where we are not well protected and thus are vulnerable to having an overgrowth of a variety of opportunistic “bad bacteria” that are not destroyed by things like antibiotics and chlorine and so proliferate and then take up residence in the gut. These can run the gamut of yeasts such as candida to iron gobbling bacteria to nasty forms of e-coli to histamine-producing bacteria. The list is daunting and long and enough to make a person cower under the bedclothes in perpetual fear.
But never fear….fermented foods are here!
Taking a small amount of naturally fermented foods several times a day is an easy way to keep our microbiome replenished, balanced and healthy. Remember not to heat them up, as this destroys the beneficial bacteria. Many store bought yogurts and sauerkrauts have been pasteurized (heated) after being fermented or have additives in them that make them less valuable, so shop wisely. The probiotic content of fermented foods can vary widely. Good quality commercial yogurts will tell you on the label what probiotic strains have been used to make it, usually lactobacillus acidophilus and bifidum bacteria. There are many strains of acidophilus, some super colonizers and fighters and some less robust. Ideally, yogurt should be made from the milk of grass fed animals and yogurt cultures and nothing more. Kefir grains generally contain a nice wide spectrum of probiotic bacteria, depending upon their origin. Kefir-making does demand a bit of daily attention, sort of like walking your dog. The grains are added to milk (or water) in a jar loosely covered with a lid and left in a dark place for 24 hours. The amount of milk you “kefirize” will depend on how much you think you can use. The grains get strained out and the milk put in the frig. The grains will then need to be added to another jar of milk to keep them fed or they will perish. Putting the grains in the frig (in some milk) will slow the process. Kombucha produces acetic acid and yeasts and may produce beneficial bacteria as well, depending upon the scoby and how long it ferments. Sauerkraut and kimchi are made by the natural fermenting action of lactic acid and yeasts. The lactic acid produces several strains of lactobacillus probiotic bacteria. Miso and tempeh are cultured using specific probiotic-producing fungi that have been used for hundreds of years. To keep those probiotics alive, add miso to soups and stews after the heat has been turned off and cook tempeh gently with low heat.
Yogurt is an easy fermented food to make. You can use dairy or nut milk or non-GMO soy milk. Initially, a commercial culture is required. Non-dairy starters are tricky to find. Using the contents of 1 or 2 high quality probiotic capsules to culture your yogurt can work for dairy yogurt. Investing in a yogurt maker is a great idea, or you can use a non-plastic 1-litre thermos. A dairy thermometer is also a helpful tool for yogurt making as you will need to heat up your milk to just below the boiling point – around 190F – in order to kill any undesirable bacteria it may contain and then cool it to around 90F before adding your yogurt starter. Having it too hot will kill the bacteria in your starter and having it too cool will mean that the starter will not start. If you are using a thermos for incubating your yogurt, pre-warm the thermos by putting boiling water into it and letting it sit while you are getting the milk and starter nicely mixed up together. Pour the boiling water out just prior to pouring the yogurt mix in. Follow the instructions on your yogurt starter for how long to incubate your yogurt. It gets tangier the longer you leave it sit and often if it has sat a bit too long it will separate with a watery layer on top.
You can use 1/4-1/2 cup of your current batch of yogurt to start your next batch instead of having to use the commercial starter each time. It is a good idea to separate out that next time’s starter and place it aside in its own glass container in the frig. Usually the initial batch made with the commercial starter will require longer incubation time than subsequent batches made by using your saved starter.
The yogurts made from milks other than dairy often don’t become firm when they are finished. They should taste tangy, though. To make them thicker once they are done fermenting you can use powdered agar (a seaweed derivative). To thicken 1 litre of yogurt, pour the yogurt out of your yogurt maker cups or thermos into a bowl. Mix 1 tsp. of the powdered agar in 1/2 cup of cold water and then place in a small saucepan and bring slowly to boiling, stirring constantly. When it begins to thicken, add it slowly, stirring all the while, to the finished yogurt. Then pour into whatever glass jars you will be using to store the yogurt in. It will gel once you put the yogurt in the frig. If you plan on using a bit of your non-dairy yogurt to start your next batch, separate it out before you add the agar. I have found that non-dairy yogurt does not work very well for starting subsequent batches. You will likely have to add a small amount of the commercial powdered starter as well.
* no copying without permission * Jo Phillips, R.N.C.P.; A.A. Nursing. * Registered Nutritional Consultant * jo.p@shaw.ca * 2016