Saturday, 4 June 2016

The human microbiome

What food should I eat?  What food is good for me? What food is good for my bacteria?  Now I have your attention. What do you mean by bacteria?  Who cares about feeding them?

Everybody (or every body) houses millions of bacteria. They live everywhere. In the gut, the mouth and on the skin.  They are generally non-pathogenic; existing harmlessly and symbiotically with their host.

You could use the term microbiome or microbiota to describe the bacteria that inhabit or live on humans. There are trillions of microbes in the average human microbiome and it accounts for 1 to 3% of total body mass.
 
How many microbes in the average human microbiome?

Estimates of the size of the human microbiome vary from 40 trillion microbial cells to 100 trillion cells. One estimate has the human microbiome as outnumbering human cells by  1.3 to 1. Other estimates have a figure of up to ten to one.  Nobody knows how many bacteria are commensal with you at the moment. It will vary in the one person continuously. Every time you defecate you lose more bacteria than human cells so the ratio of human cells to bacteria will change.
.
What does the human microbiome consist of?  Largely hundreds of different bacteria. Also some fungi and viruses, though much less.  It is known that the human microbiome is highly variable both within a single subject and between different individuals.
The problem of elucidating the human microbiome is essentially identifying the members of a microbial community which includes bacteria, fungi, and viruses. This is done primarily using DNA-based studies. You can actually get that done by sending a few samples to the relevant place.  It has become possible within the last ten years.

Where does the microbiome come from? Within seconds of being born a new born baby has been colonized by intrepid explorer bacteria largely from the mother. These bacteria can divide every 40-60 minutes so if conditions are suitable they increase rapidly.
Microbiomes are crucial for health. They are essential for digestion, control the calories we absorb, provide vital enzymes and vitamins as well as keeping our immune system healthy.  If you get the wrong bacteria in your microbiome then the microbiome has also been linked to disease such as diabetes, rheumatoid arthritis, muscular dystrophy, muscular sclerosis, fibromyalgia and some cancers.  They play a role in obesity and some psychiatric disorders such as depression and bipolar disease. In fact the number of diseases that have been linked to microbiome is so large I can’t mention all of them. I will return to this subject.

Microbiome and diet.  Your microbiome influences and determines what happens to the food you eat.  They decide lots of things such as if the food you eat is stored as calories or not. The bacteria in your gut largely decide what is going to happen to the food you eat.  So the microbiome determines what happens to the food you eat. And the food you eat determines your microbiome.  The two are connected.

What microbiome is the healthiest and best one to have?

What diet leads to the best possible microbiome?

In coming posts I will attempt to look at some of the answers to these questions.
 

Healthy food

Healthy food is low in refined carbohydrates (white flour and sugar), low in saturated fat, high in complex carbohydrates (whole grains and legumes), high in fibre and high in vitamins and minerals.

If I have doubts about what to eat I go for the safety of unprocessed plants: fruit, vegetables, whole grains, legumes and nuts. This is what the recipes in this website are based on.

White sugar is unambiguously bad for you. The less processed sugar you can eat the better for your health. You can take your favourite recipe for biscuits, cake or a sweet desert and cook the recipe as normal sans sugar but the problem is it will not taste very nice and be difficult to persuade people to eat it (irrespective of how healthy it is).

The problem is that the routinely used plain white flour has no flavour but it teams up very well with white sugar. The two combine beautifully. If you want to cook without sugar then you also need to jettison white flour. White flour (and I don’t know why) without white sugar does not taste very nice.  If you replace the plain white flour with flour made from whole grains (wheat or rolled oats) then you find you can finish up with something healthy, flavoursome and popular.

Another thing you can do if you eliminate sugar from a recipe is add extra essence or spices. Vanilla essence, orange essence, rose water, almond essence, cardamom, cinnamon, nutmeg, star of anise. It doesn’t take long to change a sweet tooth into a tooth that appreciates and savours a multitude of flavours.

 I don’t like the idea of adding artificial sweeteners. It’s my experience that weaning people off a sweet tooth is possible and much preferable. The idea of replacing sucrose with fructose also doesn’t inspire me. Sugar is sugar. It doesn’t matter if it comes in the form of white sugar, honey or fructose it’s still full of calories (leads to weight gain, diabetes, heart disease) and will rot your teeth.

I also intend to include in these pages recipes for vegetables. The rationale is: fill up on healthy vegies and decrease or eliminate the need for sweets, biscuits, cakes and dessert.

Backyard food 2

Growing your own food helps when you buy food.  Your knowledge about when foods ripens; what ripens on the tree; what ripens after picking helps buy appropriately.  Knowledge about the seasons; what is fresh and seasonal; what grows locally and what cannot, helps in knowing what to buy.
 
Growing food improves ones cooking of food. It forces people to cook in a generic manner. To use what is available.  To learn basic recipes that can be adapted to suit what is available.  I can explain.  Generic cooking involves learning how to make a crumble topping.  The topping can be used over any fruit which is available; plums, apples; pears; berries.  This is the opposite of the cooking that celebrity chefs promote.  They give a recipe and a detailed list of all the ingredients.  There is pressure to rush to the shop; buy the ingredients as prescribed and follow the recipe. It will not look like it did on TV.  It is depressing, time consuming and gives all the power to the chefs.
 
You are pressured to buy the books with the photographs.  Every body owns multiple cookbooks (they make great presents).  In contrast to the past, when women owned very few cookbooks.  In the past cooking books were about techniques, basic principles, generic cooking and contained very few photos.  Not inseparable from the personality of the chef and full of recipes which are so detailed and so specific you cannot ever get it right.
 
Meanwhile all the chefs and all the books are competing against each other.  They have to come up with new ingredients; new flavours; new countries; something different.  This normally means exotic ingredients.  Ingredients that involve more transport, more storage, are hard to find and have no cultural significance (They are not what you had as a child).  You can see why young people give up, buy a prepared meal to reheat, or a ready-made sauce, or dial up for a pizza.  If the trend continues young people will spend all day watching cooking programs, buying cooking books, feeling powerless and never ever cooking anything.
 
Our food culture has not arisen from a peasant subsistence culture.  There is no knowledge of indigenous foods and local climates.  No knowledge of wild plants and animals and how they can be harvested or used.  No intrinsic knowledge of what grows well in our particular area.  No ceremonies associated with harvest or certain foods coming into season. We don't have this knowledge, recipes, language and the cultural events that go with indigenous food.  Everything has been introduced.  There is virtually nothing that we eat that was growing here (locally) more than 200 years ago.
 
If the pantry or kitchen is full of prepared foods such as biscuits, people are more likely to eat individually:  to continually drift in and snack.  The alternative is to have set meal times and to sit down and eat as a family.  The latter is preferable for social, emotional and health reasons.  To treat food as a scare resource, something special that must be looked after leads to family meals, good eating habits and healthier people.  This is more likely to happen if the cook puts in an effort, takes her time in the kitchen, cooks with love, treats the ingredients as something precious and doesn't thrown a prepared meal on the table.

Backyard food 1

Everybody is talking about food.  Celebrity chiefs and cooking programs are bigger than ever.  The shops are full of cooking books and a bigger and better variety of food than ever before. The cooking habits and the diet of the young people I meet is worse than ever.
 
Ignore all that for a minute go back to basics, back to the beginning.  When I sit down and look at the food lumped on the plate in front of me I may be thinking about many different things; about work or what's on TV or I may even be thinking about the food.   If I'm thinking of food I'm thinking about…… the back garden. 
 
Taste:
Food should tastes nice.  I want the ingredients to taste good separately and in combination.  Consider the textures, contrasts, smell and presentation.
Food grown and cooked yourself is normally tastier because it's fresher.  Fresh broad beans, figs or tomatoes cannot be bought.  A lot of bought food has to be picked half ripe because of the time involved in transport and because ripe food is often soft, bruises and spoils quicker.  Homegrown food is normally tastier because you can select tastier varieties.  You can go by different criteria from that of the supermarkets or farmers.  You don't need to select varieties that transport or store well.
 
Nutritional Value:
Food should be healthy.  It should be full of vitamins, minerals and antioxidants; high in fibre and low in fat or sugar.  Food should be free of harmful bacteria, toxins or poisons.
Backyard food is normally healthier.  In many cases the food deteriorates in nutritional value from the moment it is picked.  If the bought food is stale and lacking in taste you need to add flavour; this often increases the fat or calorific content of the food. It makes the food unhealthier.  Adding extra ingredients to the food also decreases the ease of cooking and increases the cost.  A lot of bought food is over-processed with many added ingredients that do nothing to improve the nutritional value of the food.
Backyard food can also be grown free of chemical sprays. 
 
Simplicity:
Food should be easy to prepare or cook.  Simple easily learned techniques.  Techniques that can be applied to a variety of dishes.  It doesn't necessarily mean things that can be cooked quickly.  A simple technique often can mean the opposite: long slow cooking. 
Backyard food lends itself to easy simple cooking or even no cooking at all:  salads or the eating of freshly picked fruit.  Restaurants lead themselves to the reverse.  If you sat down in a restaurant to a dessert of a freshly picked fig cut in two you would feel cheated.  No effort or preparation gone into the food.  There might have been a lot of effort put into growing the food but in restaurants we only appreciate effort in the preparation of food.  The more complicated and involved the recipe the better.
 
Money:
Backyard food is cheaper; assuming you are not counting the cost of your labour.
 
The emotional value of food:
Food needs to have a high emotional value.  This is different for different people at different times in different cultures.  Family favourites.  Recipes that have been used for generations in the same family.  Foods that your mother and her mother cooked.
 
Some foods bring back fond memories.  Traditional recipes from the home country.  Recipes associated with certain places or times.  Unfortunately in our immigration society many people have migrated and moved from where their antecedents lived, so what may have been good local seasonal food for their parents may no longer be appropriate. There can be a conflict between traditional food and fresh, locally grown food.
 
For a vegetarian, vegan or anybody with religious or health constraints the emotional value of food depends on the food meeting personal rules and philosophies.
 
Food has a spiritual value.  If you plant a seed and months later eat the fruit of your labours, it illogically tastes better.  It is that indefinable extra spiritual element. 
What is the emotional value of home-grown food?  It is indefinable and difficult to quantify but it exists.  To see the fruit develop and anticipate it's ripening; to succour and support it through climatic vicissitudes; to await the day it ripens; to anticipate and pick it.  All this gives the food a value that you wouldn't get from the same food bought in a shop.
 
The environment:
The transport and storage of bought food leads to release of greenhouse gases and global warming.  Extensive monocultures lead to irrigation, weedicides, insecticide, salinity and erosion.
Home-grown food is often associated with compost which is associated with retaining household scraps and not placing them into the rubbish bin.  This helps preserve depleted landfill areas.

Recipe for Apple Crumble

Apple crumble
 
The Topping
 
Using plain flour means you need sugar. Avoid them both.
 
Instead use rolled oats as the basis.
Add a tablespoon of cornflour or semolina. ?baking powder
Could add a bit of polenta for a different flavour.
Add margarine or a vegetable oil to hold the oats together.
 
Mix all the topping ingredients together with your fingers. The crumble mixture should be dry and crumbly: Like bread crumbs.
 
Additional extras for the topping:
 
Ground ginger
Cinnamon
Star of anise
Nutmeg
Cloves
Allspice
Grated orange rind
Desiccated coconut
Wheat germ
Pepitas
Sunflower seeds
Unsalted nuts (almonds, hazelnuts, walnuts, pine nuts, pistachio, pecans)
 
 
The base
 
The base consists of fruit either alone or in combination.
 
Apple
Rhubarb
Peach
Pear
Plumb
Apricot
Quince
English gooseberry
Cape gooseberry
Blackberry
Raspberry
Mulberry
Feijoa
Guava
Pineapple
Mango
Loquat
 
 
To be used in combination with other fruits
Figs
Dried fruit soaked in liqueur
Red or black currants
Grapes
Cherries
Lychee
Passionfruit
 
 
 
Place the fruit in a bowl. 

You would not normally need to add water but if the fruit is dry a little bit of water would be beneficial.  A spoonful of cornflour would help if the fruit is watery. Cover the fruit loosely with topping. You shouldn’t need to grease the bowl but you can if you are worried.
 
 
Cooking time
 
Will depend on fruit used and size of dish. If the fruit needs cooking (i.e. apples) bake at 180°C or 40 minutes. If the fruit only needs heating only (i.e. berries) then bake for 20 to 25 minutes.
If making individual crumbles then cook for about15/20 minutes at 180°C.
 
Serve with a milk product: cream, custard, yoghurt or ice-cream.
 

Recipe for fruit mousse

The basic idea is make a smoothie. Lighten it by adding air. Decorate. Solidify it. That’s all Easy peasy. The ideal way of eating fresh seasonal fruit.

To make the smoothie you need some puréed fruit plus yoghurt, milk (cow’s milk, soya milk, coconut milk or anything you fancy), cream, buttermilk or skim milk powder.   You need about 500ml. You can also add a protein milk powder if you are into such things.  You can also add a liqueur, or spirits.
 
To lighten your smoothie you need to add either whipped cream or beaten egg whites.  I prefer egg whites.  One egg will be enough and you can add the yolk to the smoothie.
 
Now add either gelatine or (if you are a vegetarian) agar.  Use enough to set 500 ml of liquid.
 
Whisk together the smoothie, the dissolved gelatine/ agar and the egg whites. Pour into a large bowl or into individual desert bowls. Decorate with fresh fruit, glazed fruit, nuts nutmeg, cinnamon, mint leaves, flowers.  Place in the fridge until set.
 
That is the basic recipe. To get you started I will list a few of the hundreds of recipes floating around in books or in the ether.
 
 
Some fruit can be used either raw or cooked. Peaches, plumbs, apples.  Cooked is preferable. More flavour and better colour.
I prefer not to add sugar or honey unless really needed. Rhubarb, passionfruit and quince.
I prefer yoghurt. If feeling spartan go with the skim milk powder. If feeling decadent use cream which is not recommended for regular and daily use.
Remember when tasting the smoothie that adding egg whites to the smoothie will dilute the flavour.
Adding lemon juice will slightly intensify the flavours.
 
 
 
 
Apricots; vanilla essence; decorate with blanched almonds.
Quince.
Raspberries; orange juice.
Mango; orange juice; rum; decorate with mandarin pieces.
Passionfruit pulp; caster sugar; orange juice;
Pawpaw; mango; rum; lemon juice.
Pineapple (cooked); grated orange rind; honey.
Rhubarb; brown sugar; white wine; grated orange rind;
Black grape juice; blackberries;
Pineapple (cooked); banana; passionfruit; peach; mango.
Blanched almonds; banana; vanilla essence; decorate with grated nutmeg.
Blueberries; raspberries; honey; decorate with sesame seeds.
Orange juice; carrot juice; pitted prunes.
Pineapple; banana; fresh ginger.
Fruit juice; honey; banana;
Peaches; cinnamon
Hazelnuts (roasted and finely ground in a food processor); coffee.
Persimmon.

Recipe for Bread

Bread
 
Main Ingredients
 
Plain flour
Whole grain flour: This is the critical ingredient in making healthy, tasty bread.   Whole grain flour is elusive and difficult to get[1].  It is the milled grains of wheat: nothing added and nothing taken away.  It is not wholemeal flour which has various definitions but normally means plain flour with colour and bran added.
Gluten
Water
Dry yeast
Sugar
Salt
Olive oil or canola oil
 
 
For a small loaf use 300ml of water. For a big loaf use 400 ml.  For an even bigger loaf (or rolls or two small loafs) use more water. The critical thing is the ratio of water to flour.  Which is approximately 100ml of water to one cup (250ml) of flour.  This varies depending on the type of wheat but it’s a good place to start.
 
 
Place 300ml of water in a beaker.
Add a tablespoon of dry yeast. Add about a tablespoon of sugar. Add about a teaspoon of salt. These are all approximates. It doesn’t really matter that much. You can even leave out the sugar and salt if you wish (but it will take longer to rise).
Place the water in the microwave for about 30/45 seconds. This will speed up the rising time.
You need about three cups of flour. You would normally go with about two cups of wholegrain flour and one cup of plain flour. You would need about two tablespoons of gluten added to the plain flour.  Place the flour in the microwave for about 45/60 seconds. This will speed up the rising time.
Add about two tablespoons of oil to the water. Amount of oil you add is not critical. Vary to suit. Wisk the watery ingredients.  Wisk the various flours together.
Add the fluids to the flour. Stir it with a knife or a spoon. It should be dry enough to pick up in your hands. This is the important part. Getting the right consistency and needing the bread for long enough. The only way is by having a go. If it’s too wet then pick up the dough and dip it into some flour. Then go back to needing. Difficult to explain. You really need someone to show you at least once. Perhaps ‘YouTube’. If the dough is too dry then you need to add water. More difficult but can be done by pushing holes into the dough and then pouring water in.  It comes done to feel, instinct and trail and error.
Needing should take about 5/10 minutes. Needing is finished when the dough hangs together. It develops elasticity.  More trail and error.
Place some glad wrap over the top of your bowl and then cover with a tea towel. Let stand. The time it takes to rise depends on the room temperature. If you have heated the water and flour and the room temp is above 20 degrees C it should take about an hour and a half for the bread to rise. When ready it will have more than doubled and tiny bubbles will start to appear in the surface of the dough. If you haven’t heated the water and flour it will take 3 to 4 hours for the bread to rise at the same room temperature.  If the room temp is getting down around 10 degrees C then it will take forever to rise. You need to place such dough near a heater. If the temp is above 30 degrees C then you don’t really have a problem. The dough will rise very rapidly. Probably about an hour.
 
When it is fully risen it then needs to be knocked back. Punch the dough and knock the stuffing out of it. Then put it in a tin or on a tray to rise for a second time. This will be quicker this time. About 20/30 minutes. It should roughly double in size. If you leave it too long the resultant loaf will be full of air bubbles especially in the top half. Too little and the loaf will not be as light as it could be. Once again this is a question of trial and error and personal preference and will vary from day to day depending on the room temperature and type of flour.
 
Now cook the loaf in a pre-heated oven. About 175 degrees C for 35 minutes (for a 300 ml loaf) . For a 400ml loaf cook for about 45 minutes. Rolls for about 25 minutes. 
More trial and error. Ovens vary tremendously. So does personal taste. For a crusty loaf cook for longer or at a higher temperature. For a moister loaf that keeps longer cook then cook for the  shortest time possible.
 
The basic dough recipe can be used to make loafs, rolls, flat bread or pizza. Though you need to change oven temperatures and cooking times. Use your imagination.
 
To cook bread it is very much a question of feel or the vibe. The only way is to experiment. Most failures are edible. Just do it. Get the feel for needing the dough; get the vibe that tells you how long it should rise for and how to cook it.
 
The basic variations:
Add herbs; fresh or dried
Add olives, sun-dried tomato, grilled capsicum
Add nuts, dried fruit, soya grits, sunflower seeds, pumpkin kernels 
Coat with poppy seeds, sesame seeds, polenta
Add bread improver: the bread keeps longer
Add wheat hearts or semolina
 
Vegetables: If you add mashed vegetables to the dough you need to decrease the amount of water. The alternative way is to grate the vegetable; place in a tea towel, squeeze the liquid from the vegetable and then add the dried vegetable to the flour and the juice to the liquid. This method works really well for unwanted zucchini.  Add the squeezed grated zucchini to the flour and decrease the total amount of liquid slightly. The resultant bread will be moister than normal and last longer.
 
Exotic flours: you can easily replace some of the wheat flour with flour made from rice, rye, barley, oats, maize, sorghum, millet, buckwheat, legumes, and potato. I’m sure I’ve missed something but you get the point. Replace a cup of wholegrain wheat flour with any other flour and you will not have to alter the basic recipe. If you start taking out more wheaten flour you made need to add extra gluten. If the loaf is crumbly; like a muffin or a scone then it is lacking gluten. A crumbly loaf is not a complete disaster, you can still eat it but the loaf will not keep well and the trail of crumbs will not please everybody. Personally I prefer gluten.
 
If you cannot acquire or make some of the more exotic flours another option is to add rolled grains to the flour. Substitute a cup of rolled oats (or barley, rye, triticale) for a cup of flour and proceed as normal.


[1] One reason being whole grain flour contains oil in the wheat germ and has a short shelf life.