Cabbage offers vital support in resistance to cancer. New research suggests new molecular evidence.
This blog reflects a growing interest in the benefits of consuming fermented food as a way of improving health and wellbeing. Cabbage is a popular vegetable in Europe, and it is one of the simplest things to start fermenting at home. Most parents would have urged their children to ‘eat up your greens’ at some point, but the real value of this advice is only just starting to emerge. Cabbage is part of the cruciferous family (brassicas) which includes lots of vegetables long associated with a healthy diet such as kale and broccoli (wasabi and horseradish too incidentally). Including them in your diet has long been recognised as a good idea. With a growing understanding of the link between lactic acid fermentation and good gut health, cabbage is being thought of as a superfood, able to increase protection against a wide range of health problems.
News published today on the BBC website adds yet another dimension to the benefits of eating cabbage. Scientists at the Francis Crick Institute have identified anti-cancer chemicals created in the process of digesting brassicas, including cabbages. It is supposed that a chemical (indole-3-carbinol) created when cabbage is broken down in the body, encourages the healthy renewal of the bowel lining. The cited research was not carried using fermented cabbage, however the long standing association between sauerkraut consumption and healthy bowels suggests to me that fermentation may have a favorable link with indole-3-carbinol production.
This research was carried out on mice so how it translates to humans is as yet uncertain (is the use of mice really necessary?). And as already mentioned this wasn’t a study on fermented cabbage.
Finally I just want to remind everyone of the importance of eating organically whenever possible. In a recent court case in the US, a man was awarded £226m in damages after claiming that his cancer was caused by a weedkiller that included the compound glyphosate. Despite being developed by a powerful chemical company (Monsanto), glyphosate has been attracting health concerns for some considerable time. France plans to ban it’s use within three years and at least one study by the UN argued it is probably carcinogenic in humans. While washing vegetables before consumption is always good practice, many chemicals used in agriculture like glyphosate are absorbed through foliage and roots. I’m uncertain of the extent to which glyphosate is present in the production of brassicas, but going organic is the only way to be sure.
Kefir appears to offer significantly greater benefit than commercially produced probiotic drinks.
Dr Michael Mosley has been helping to run a study for the BBC looking at the relative benefits to gut health from a range of products. Volunteers and scientists collaborated to try to discover which of three probiotics/prebiotics had the biggest positive impact on gut bacteria.
The first product was a commercially available drink, branded as a probiotic and available in major supermarkets. The second item up for comparison was kefir, a traditional milk and yeast fermented substance, a little like yogurt. These first two foods were compared with vegetables high in natural prebiotic fibre called inulin. Inulin is found in range of foods including chicory (chicory root is a rich source) and scallions (onions, leeks and garlic).
The poorest preforming of the three in this trial was the probiotic drink. The participants in this group demonstrated a modest (statistically non significant) change in lachnospiraceae gut bacteria. Conversely significant changes in gut flora were seen in the group consuming prebiotic fibre. The people that consumer kefir enjoyed the most positive increase to gut bacteria.
It should be pointed out that any comparison between prebiotics and probiotics is not a like for like test. Prebiotics deliver the food that supports existing bacteria and create the conditions for further colonization. A probiotic is intended to introduce microorganisms directly into the body.
The BBC study concluded that traditionally produced fermented foods (or even home made versions) may offer the greatest benefits to consumers in terms of increased gut flora. A key problem with mass produced fermented foods and drinks is pasteurisation. Pasturised goods are regarded as safer, which also correlates to a longer shelf life. By comparison traditionally made kefir has to be consumed in a relatively short space of time. This is perhaps the choice we consumers face, if we want maximum health benefits from the food we make or buy we may have to sacrifice some of the convenience of long sell by dates.
As science begins to unravel the importance of gut bacteria to health and wellbeing, there’s never been a better time to learn about human microbiota.
So what’s the big deal about the fermentation of food and drink? Why is there such an interest in it now when it’s been around for thousands of years? The growing ability of science to study microorganisms has opened up research linking the human microbiome to a range of health and wellbeing benefits. Even though this research is at an early stage, there are signs that our understanding of the human condition is entering a new era. Fermentation has a central role in this process, prebiotics and probiotics may be able to make a significant contribution to the quality of our lives and the state of our health.
The awareness that fermented foods may be beneficial is a useful starting point, but there are resources available for anyone wanting to know more. Maggie and I have signed up for the Coursera MOOC, Gut Check; Exploring Your Microbiome. MOOCs are multiple open online courses; essentially short samples of higher and further education. They are typically free and offered by experts in their fields. All materials are available online, and a study commitment of three to five hours for between four to eight weeks are required by students. There is usually an assessment required to complete a MOOC and a verified certificate may be available for a fee.
We will provide a weekly report of the Gut Check MOOC. But for anyone considering signing up for the course, it starts with a basic outline of the microbiome and microbiota (What is the human microbiome? What’s in your gut and how is the human microbiome studied?). It takes a little effort, but it is accessible to most people with a desire to learn and a basic knowledge of biology. This course is offered on the Coursera platform, there are other MOOC providers and free courses available in the same or similar areas of study. We welcome feedback about this or similar resources, feel free to enter your comments in the box below.
Home fermentation, have you tried the Kilner fermentation set?
Is a home fermentation kit necessary? For the occasional production of sauerkraut I’m not sure that special equipment is essential. Maggie has managed to keep us supplied with our fermented foods simply by using medium sized jam jars, and a range of normal kitchen utensils. The point she always stresses is that everything has to be clean. The fermentation vessel should be thought of as a bacterial incubator. If you incorporate harmful bacteria into the incubator it will inevitably grow quickly. You should throw any tainted product away , clean everything and start again. One of the many appealing aspects of home fermentation is the relatively low cost of fermenting produce. Consider that at current prices a liter of organic sauerkraut can be created for less than 50p (ten bob!).
I know that previous generation of home fermenters from Poland and Germany actually had a range of fermentation pots and tools that were accumulated through the course of married life (I don’t remember seeing any of these is the kitchen of my mother or grandmother). In particular ceramic pots that were dedicated fermentation vessels. They had necks wide enough that a small plate or large saucer could be accommodated within to keep the fermented product under the water level.
With the rising interest in home fermentation equipment has passed from specialist shops and online retailers into mainstream retail outlets. We purchased a Kilner fermentation kit at the weekend. Our primary motivation was to increase the volumes of our product. Not only has our own consumption increased but we are also sharing more with our own friends and family. It certainly seems that the public awareness of the benefits of fermentation is growing. The Kilner kit was fairly priced (£18) when compared to similar products and the fermenting jar was around the size we were looking for (3 liters). It all seems OK, we’ll report back when our first batch is ready (cabbage and carrot). We have no particular connection with Kilner, save that we use their 1liter fermentation jars already.
We’d be really interest in what other home fermenters use, and any equipment related tips would be most welcome. Feel free to leave any suggestions, comments or feedback in the box below.
Is temperature linked to the quality of your sauerkraut?
In the short time we have been running this blog we have been asked about the optimum temperature for the fermentation process to take place. We have successfully fermented a range of foodstuffs at room temperature, let’s say from 18oC to 22o. There is no method in this, it is simply that Maggie was brought up to leave the fermenting vegetables in the kitchen or a heated utility room. As such we’ve never been tempted to leave them in the garage or garden shed. As different types of cabbage take different amounts of time to ferment into sauerkraut, it always seemed likely that temperature is a variable in the process.
I eventually became impatient not knowing, I was also intrigued by the idea that the quality of our own sauerkraut fermentation could be qualitatively improved by allowing it to take place at a slightly lower or higher temperature. The first two science papers I found dealing with the issue didn’t offer explicit conclusions, however third time lucky! India is one of the world’s big producers of cabbage, the spoiling of the raw cabbage before it gets to the consumer is a significant problem. So Indian interest in fermentation is something that is culturally relevant but also has commercial implications. An article in the Indian Journal of Ecology from 2017, Effect of Temperature on Fermentation and Quality of Sauerkraut provided a lot of useful data.
In an experiment, Pran Krishna Thakur, Payel Panja and Jahangir Kabir tested the quality of sauerkraut produced at a low (15o-20o C), ambient (25o-30o C) and high (35o-40o C) temperatures. The paper is well written if you’d like to know more about yeast and bacterial profiles of sauerkraut fermentation at different temperatures follow the link. However the headline is that the sauerkraut was of a higher quality when fermented at the lower temperature (15o-20o C). This is in line with the general advice, however it’s worth noting that the experiment was undertaken with the shaan variety. I suspect that there may be some variability with different types of cabbage, but that’s a story for another day.
Show someone your love by taking an interest in their long-term health and wellbeing. Fermentation is a game changer.
The media (traditional and social) are full of valentine news, view and suggestions. Local traders, shops and supermarkets have an overwhelming array of products linked to St Valentine’s day. However the way in which you decide to treat your loved one says a lot about you. Whilst chocolates, Champagne or roses spring immediately to mind they may by simple clichés of what people are supposed to give, rather than lasting indications of love.
Perhaps a different approach would be to offer your partner (and yourself) something likely to offer nourishment and a lasting health benefit. It is easy to overstate the qualities of naturally fermented probiotics. But we can feel confident that they are likely to make a long lasting contribution to wellbeing in a number of ways. Evidence is starting to emerge that positive gut flora, may be correlated with, stable weight, and generally improved physical and mental health across a number of measures.
Clearly probiotics are not just for February the 14th, and moving towards a healthy diet is a long term project. But talking about fermented foods or trying them for the first time, may be a great way of showing your partner that you really care, and that you want them to enjoy the best possible health. When you create fermented foods at home, not only are your own family exposed to the product, but the idea and your positive actions can influence a wide circle of friends. Something that can’t be said of a bottle of fizz or a bunch of roses.
Whatever you do, and whoever you do it with have a great day.