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  • Adriano dos Santos

Understanding Kimchi - The Science of Fermenting Cabbage

Fermented foods, such as sauerkraut, kimchi, kombucha, have become popular for health reasons. I have made my own sauerkraut in the past and have tasted wonderful kimchi dishes at a humble Korean restaurant in London "Simya restaurant in Fulham". I was introduced to this restaurant by a friend of mine, Robert Mansell, who funnily enough had no clue that we were about to immerse in such a healthy eating experience. I loved it not only for the taste but also for the hope that the bacteria responsible for the fermentation of the cabbage — lactic acid bacteria (LAB) — would contribute to the diversity of our gut microbiota.

What is it actually?

Kimchi is a simple Korean pickle, a fermented mash-up of vegetables like napa cabbage and scallions. It’s easy to make. And it’s everywhere: from modest ramen houses to the trendiest of tapas bars. It’s crossing cultural barriers on menus and filling home refrigerators, from the dorm room to your suburban mom’s well-stocked kitchen. Chefs are slapping it on burgers, layering it into grilled “kimcheese” sandwiches, and even sneaking it into your Bloody Mary. But how can something as basic as cabbage, salt, and spices be so buzzworthy? It’s simple: science.

Kimchi relies on fermentation, or the digestion of sugars into acid, gases, or alcohol (don’t worry, your kimchi won’t be boozy). It’s the fermentation process that gives kimchi its trademark effervescence, tang, and delicious funk, harnessing the natural interactions between bacteria and their environment.

Why fermented food?

I was amazed a couple of years ago to learn that the fermentation of food has been used by humans for thousands of years as a way to preserve foods, and that the health benefits go beyond their microorganisms (don’t worry, citations are provided below). The fermentation process enhances the nutritional quality of food by contributing beneficial compounds such as vitamins, and by increasing the bioavailability of minerals. Probiotics, including those found in kimchi, have a range of positive effects on health, including the improvement of various intestinal inflammatory conditions, positive impacts on the immune system and even weight loss, and can alter the composition of the gut microbiome.

1) Reducing the acidity in the body

These bacterias are facultative anaerobes, meaning they can survive both in the presence and absence of oxygen. Either way, they create lactic acid as a by-product of their digestion, which creates an acidic environment, lowering the pH (the measurement of how acidic, neutral, or alkaline something is) and preserving (or pickling) the cabbage. The lactobacilli also make carbon dioxide (which results in the bubbly zing) and create flavorful compounds.

2) Better digestion = better nutrient absorption

A high quality probiotic food such as sauerkraut, kimchi, kombucha can help populate the beneficial bacteria that’s naturally found in the gut, supporting digestive and immune health but also helping to ensure that your body is properly absorbing the nutrients it’s extracting from your food.

Proper nutrient absorption will maximize the impact of any vitamins, supplements and even medications you’re taking - which will save you money and may even allow you to decrease the dosage! In short, probiotics are one of the best food you can eat to make sure all of the other beneficial nutrients and supplements that you are having in your life are effective.

3) Reducing inflammation

Inflammation normally helps your body fight off infection, but chronically high levels of it may cause swelling and pain and damage tissues. Psoriasis, ulcerative colitis and chronic fatigue syndrome are all diseases in which inflammation is thought to play a role.

In one new study, patients with one of these conditions who took the probiotic bacteria B. infantis for eight weeks had lower levels of inflammation compared with those who took a placebo. And healthy people who took probiotics also saw a reduction in inflammationcompared with those who took a placebo.

The results suggest that probiotics may lower levels of inflammation, regardless of the affliction, the researchers said.

More benefits

includes anticancer, antiobesity, anticonstipation, colorectal health promotion, probiotic properties, cholesterol reduction, fibrolytic effect, antioxidative and antiaging properties, brain health promotion, immune promotion, and skin health promotion.


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