The microbes
associated with our
food tend to have
a bad name – food
poisoning is often
in the news.
Yet while some make us ill
and others can be a nuisance
by spoiling our food, without
microbes there would
no bread, cheese, beer or
chocolate. Friend or foe – food
microbes are always on the
menu.
MICROBES & FOOD PRODUCTION
For thousands of years, humans have taken advantage of natural fermentations to make a diverse
range of products, including bread, yoghurt, cheese
and alcoholic drinks, although until relatively recently
no one understood that micro-organisms were
responsible for these processes.
Fermentation improves the taste, texture and smell
of food products through the conversion of sugars
into acids. It also causes changes that reduce the
growth of unwanted food microbes. This improves
the food’s storage life and safety. Nowadays
fermentations are used to make an amazingly wide
range of food and drink, including salami, soy
sauce, olives and chocolate.
Microbes are involved in the production of foods
in other ways – they are cultured to provide food
additives such as enzymes, vitamins and organic acids
that provide flavour, texture or nutritional value to
foods or help preserve and stabilize them. Examples
include citric acid for preserving and flavouring soft
drinks, and dextran and xanthan for stabilizing salad
dressings, ice cream and gluten-free bakery products.
Some foods are made directly from microbes; mycoprotein, such as Quorn®, is made from the mycelium
(tangled network of threads) of cultured mould, and
Marmite® is made from the yeast left over from
brewing. Edible mushrooms, the fruiting bodies of
certain filamentous fungi, are a common item in our
diet. They include many fungal species that are either
harvested wild or cultivated. Agaricus bisporus is the
most commonly grown mushroom in the UK and
accounts for 95% of the total British market. Several
sizes are sold; button, closed cup, open cup and
large open mushrooms or flats. These correspond to
different phases in the growth cycle of the mushroom
and are not different varieties or species. Exotic types
like shiitake, oyster mushrooms and chanterelles
are now joining this familiar mushroom on the
supermarket shelves.
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3
Lactic acid fermentations
Lactic acid fermentation is predominantly caused by lactic acid
bacteria. Important lactic acid bacteria include Lactobacillus,
Leuconostoc, Pediococcus, Streptococcus and Lactococcus.
Lactic acid bacteria convert sugars to lactic acid. The lactic acid
gives the food its characteristic sour taste. The production of
lactic acid causes a decrease in pH which inhibits the growth
and survival of other microbes. This contributes to the improved
microbiological safety of the food.
FERMENTED FOODS
Foods made by lactic acid fermentations include:
Fermentation is a process by which
Dairy products
bacteria – usually lactic acid bacteria –
Lactic acid bacteria are used in the fermentation of milk to
yeasts and moulds convert sugars
produce many dairy products, for example cheese, yoghurt and
and carbohydrates (complex organic
fermented milk drinks such as kefir. Kefir is a popular drink in
compounds) into less complex pro-
Russia, a product of a mixed lactic acid bacteria and yeast
ducts such as carbon dioxide, alcohol
fermentation.
and organic acids. Microbes break
down complex molecules in food
Fermented meats
to provide the energy they require
for growth. As by-products they
Salami, pepperoni, chorizo and nham (an uncooked, fermented,
sometimes produce the fermented
semi-dry Thai sausage popular in Asia) rely on a combination of
foods and drinks that we enjoy.
lactic acid fermentation with curing salts and drying. Yeasts and
moulds may also contribute to the flavour of these products.
For many years fermentation was a
hit and miss process which relied on
Fermented vegetables
naturally occurring microbes getting
into our food. For example, yeasts
Sauerkraut, olives, gherkins and cucumber pickle are made by lactic
in the air would land in fruit juice
fermentation of the brine-soaked food. Successions of different
and ferment the natural sugars in it,
lactic acid bacteria are involved, sometimes together with certain
producing wine.
yeasts and moulds.
Microbes and fermentation are now
better understood and each process is
Other foods made by lactic acid fermentations include sour
carefully controlled from start to finish.
dough bread, miso, dosa (fermented pancakes) and surströmming
Special cultures of microbes are used in
(fermented herring). Some of the flavours in wine are partly due
the fermentations to give the product
to fermentations by bacteria, which break down malic acid in the
the required properties.
fruit juice to lactic acid and carbon dioxide gas.
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5
CHEESE
Ripening
Most types of cheese have to be
ripened during which water is lost
Cheese has been produced for over 7,000 years and microbes are crucial for its
and a series of biochemical changes
manufacture. In ancient times, milk used to be stored in bags made from the
causes the flavour and texture of the
stretchy lining of cows’ digestive systems. Eventually the milk would go sour
cheese to develop. The type of cheese
and form solid lumps that could be squashed together to make cheese. This
produced is partly dependent on the
was due to the presence of a digestive enzyme called chymosin (rennin) that
types of microbes used during this
is secreted by ruminants’ guts, and bacteria that fermented the lactose sugar
process. Ripening takes from a few
in the milk into lactic acid.
days to years.
How is cheese made?
Soft cheeses
Milk contains the sugar lactose and the protein casein as well as fat, water,
Brie and Camembert are sprayed with
minerals and vitamins. During the cheese-making process, the lactose is
the fungus Penicillium camembertii
converted to lactic acid and the protein is coagulated. The water is removed,
that forms a soft white mycelium
leaving a solid or semi-solid product. It is important to use high-quality milk,
on the surface, giving the cheese its
which has been pasteurized to kill any pathogenic (harmful) bacteria.
characteristic flavour and texture.
Fermentation
Blue cheeses
j A mixed starter culture of lactic acid bacteria (such as types of Lacto
bacillus, Lactococcus and Streptococcus) is added to the milk to start
These are inoculated with cultures of
the fermentation.
different moulds and yeasts. Some-
j The fermentation runs for about an hour during which time the pH falls,
times the microbes are added to
milk or curds in the vat; others are
due to conversion of the lactose to lactic acid by the bacteria.
inoculated into the formed cheeses
using wires. Penicillium roquefortii is
Curdling
used to produce Gorgonzola, Stilton
j Chymosin is added to ripe milk to produce a solid product called curds.
and Dolcelatte. The spores quickly
j The curds are separated from the liquid part (called the whey).
germinate into fungal hyphae (thread-
j The curds are washed, salted, chopped and pressed into moulds to make
like structures that form the mycelium),
solid cheese.
which run along cracks in the cheese.
Hard cheeses
Cheeses like Cheddar contain less than
40% water. During manufacture, the
cut curds are heated to 38–42 °C, which
makes them shrink and become firmer.
The starter culture can survive the heat
and continues to grow and produce
acid. When the acid level has reached
around 0.25%, the whey is run off
and the curds are formed into blocks
in a manual process called cheddaring.
The blocks are pressed to remove any
remaining whey and trapped air and
the cheese is then left to mature.
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7
YEAST FERMENTATIONS
Yeasts are single-celled fungi that are very common in the environment, but are
usually isolated from sugar-rich material such as the skins of fruits and berries.
Yeasts are used in the fermentation of fruits to produce wines, cereals to make
beer, in bread-making and flavouring in the form of yeast extract.
Bread
A yeast called Saccharomyces cerevisiae is used in bread-making. It is more
commonly known as baker’s yeast. It is thought to have originally been isolated
from the skins of grapes. (The yeast forms a thin white film which can be seen
on the skins of fruit such as grapes and plums.)
Bread is made by mixing yeast with sugar, flour and warm water. The yeast uses
the sugar and the sugars present in the flour as its food. It breaks them down
to provide energy for growth. The yeast grows by budding; as it does, bubbles of
FASCINATING FACT
the gas carbon dioxide are produced in the dough.
The bubbles make the dough expand and rise. This is because the dough is
extremely sticky and it traps the bubbles, preventing them from escaping. When
What is noble rot?
the dough is baked, the heat kills the yeast and the dough stops expanding.
Botrytis cinerea is a grey mould that
is commonly found growing on
Baker’s yeast comes in two forms:
fruit and vegetables. It is a problem,
particularly on strawberries, where it
j compressed fresh yeast – the yeast is alive but because it contains 70%
moisture it does not keep well and must be refrigerated and used quickly
after opening.
causes spoilage of the fruit. However,
under the right conditions (damp,
misty mornings which promote the
growth of the mould, followed by
j dried into granules – the yeast is alive but dormant (inactive) due to lack of
moisture. As it only contains 8% water, dried yeast has a longer shelf life
than fresh yeast and does not need to be refrigerated.
warm, dry sunny afternoons) the
presence of the mould on grapes can
be advantageous to wine growers.
Botrytis spores draw moisture from
Alcoholic drinks
the grapes causing the fruit to break
Beer and wine are alcoholic drinks made from fermented barley and grapes,
This concentrates the sugars, mag-
respectively, but alcoholic drinks can be made from a wide range of plant
nifying the flavours, to produce a
material containing fermentable carbohydrates, for example Japanese sake is
very intense, sweet wine. Under
made from rice. Spirits such as vodka and whisky have higher alcohol con-
these circumstances the fungus has
tents and are made by distilling the alcohol produced in fermentation. The
been referred to as La Pourriture
organisms that carry out the fermentation are Saccharomyces yeasts.
Noble – the noble rot!
down and become partially raisined.
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OTHER FERMENTED AND FUNGAL FOODS
Chocolate
Cocoa beans are seeds which form inside pods
on the cacao tree (Theobroma cacao). When they
are harvested, they are coated in a slimy layer of
sugary material. Microbes are used to break down
this material and prepare the beans for roasting.
The fermentation of cocoa beans is complex and
involves a succession of microbes, starting with
yeasts, continuing with bacteria and finishing with
moulds. The alcohols, acids and heat formed during
fermentation induce complex biochemical reactions
inside the beans.
Unfermented beans do not produce the chocolate
flavour and scientists have been unable to replicate
in the laboratory the complicated biochemistry that
takes place naturally on the farm.
Chocolate is a food, which can only be made with
the help of microbes! A similar, but less complex
method is used for the processing of coffee beans
to make coffee.
FASCINATING FACT
What makes the centre
of After Eight® mints
gooey?
j The contents of the cocoa pods are scooped out
Invertase is an enzyme derived
from yeast. It breaks down the
j The beans are turned daily to aerate them.
easily crystallized sugar sucrose
and piled in heaps.
j Microbes occurring naturally on the plant cause
a fermentation which lasts for 7 days.
j When fermentation has finished, the beans are
sugars glucose and fructose. This
dried and taken to the processing plant where
glucose/fructose mixture is often
they are roasted.
syrup. The fondant in the centre
of After Eight® mints is made as a
stiff paste of sucrose, water and a
small amount of the enzyme
11
into the less easily crystallized
referred to as invert sugar or
10
Making chocolate
j They are then kibbled (broken into pieces); the
broken shells are removed and the small pieces
left (called nibs) are reduced to a thick liquid,
which contains about 55% cocoa butter.
invertase. The invertase turns the
j Half the cocoa butter is removed by pressing
hard sucrose into the soft centre.
and used to make chocolate bars. The remain-
This process may take over 3
ing cocoa solids are ground up to make cocoa
months.
powder.
FASCINATING FACT
What links microbes to MSG?
Monosodium glutamate (MSG) is a food ingredient used to enhance flavour. The bacterium Corynebacterium glutamicum produces the amino acid glutamic acid from the fermentation of molasses.
Mycoprotein
Glutamic acid is then converted into the salt monosodium glutamate. Technically, humans can detect
only four different tastes: salty, sweet, sour and bitter (all other complex flavours are a combination of
Mycoprotein has been on sale to the public as Quorn® since 1985
taste and smell). But there is now thought to be a fifth: the ability to detect MSG. This is described as a
and is a popular meat substitute, particularly with vegetarians. It
meaty sort of taste that the Japanese call umami. MSG has been extensively researched and approved for
is the filamentous mycelium of Fusarium venenatum, which was
use in food, but has attracted controversial publicity due to fears by some consumers that it may cause
originally isolated from soil.
headaches and nausea and trigger asthma attacks. Most of this evidence is anecdotal and scientific
Manufacture of Quorn®
research has not been able to substantiate these adverse affects.
The mould is grown in a nutrient-rich medium in a bioreactor
called a chemostat. This is a continuous culture system that gives
good productivity. The fermenter runs for 6 weeks and is then
cleaned for 2 weeks and prepared for the next run.
The biomass and culture medium are separated and the mycoprotein is heated to 64 °C for 20–30 minutes to break down the
genetic material (RNA) of the mycelium which is too high for
human consumption.
The final product is collected by filtration under vacuum. A
mechanical process is used to align the mycelial filaments and the
resulting product is frozen for storage, flavouring and distribution
as Quorn®.
Truffles
Truffles are the fruiting bodies of filamentous fungi. The fruiting body is small, potato-like,
FASCINATING FACT
warty and gnarled in appearance, and can be brown, white or black. Some types weigh over
1 kg. There are many species of truffle, but only some are eaten. Truffles have a distinct flavour
and strong smell.
How do we flavour soft
drinks?
The fungus grows as a tangled network of threads called hyphae in association with the roots
of certain trees. This is a symbiotic relationship where each organism benefits from the other.
The truffles get their sugars for growth from the root cells and in return pass nutrients from
Citric acid is an organic acid found
the soil to the roots. Truffles are the fruit of the fungus and contain spores.
in citrus fruit. It is used as a sour
flavouring and is produced by fer-
Truffles rely on being eaten to spread their spores. Animals are attracted by the scent and
menting molasses or other sugar
dig under the leaf litter to find the fruiting bodies. After eating the truffle, the spores pass
substrates with the filamentous
through the animal’s body and are distributed into the environment with their faeces. Truffle-
fungus
hunters use animals to hunt out the valuable fungi, which can be sold for a very high price.
Aspergillus niger.
This
fungus is also used to produce
Traditionally pigs were used but now highly trained dogs seek out the truffles.
another food ingredient called
Truffles are so expensive and have such an intense flavour that they are used in very tiny
gluconic acid (E574) that is used
amounts to flavour food. Some are used to make truffle oil for sprinkling on gourmet dishes.
as an acidity regulator and is
naturally found in tea, fruit and
A white truffle weighing 1.5 kg sold for £165,000 in 2007. It was unearthed in woods near
wine.
Pisa in Italy and was one of the largest truffles ever found.
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SGM MEMBERS’ RECIPES
BAGELS –
Method
bread with
a difference
1. Put the milk, butter and sugar into a mixing bowl and whisk thoroughly.
The milk should be hot enough to melt the butter completely.
2. When the mixture is lukewarm, sprinkle on the yeast and leave to rise.
This will take some time, typically more than half an hour. To save time the
yeast can be started off in warm water and the amount of milk reduced to
allow for the water.
3. Stir in the egg white and salt, then beat in the flour to make a soft
Legend has it that the
dough.
first bagel was made
by a Viennese baker in
4. Turn the dough onto a floured board and kneed until smooth and elastic.
1683 who wanted to
pay tribute to the King
of Poland, Jan Sobieski,
for saving the Austrian
people
from
5. Allow it to rise until doubled in size (about 1 hour). Do not allow the surface
Dave Roberts’
to dry out and form a skin as this restricts the rise. To prevent this, use either
Basic Bagel Recipe
a large plastic bowl with a snap-on lid or cover the mixing bowl with cling
film or a wet tea towel.
Turkish
invaders. Knowing the
6. Knock the dough back and knead briefly to remove the largest gas
king was a distinguished
horseman,
the
bubbles.
baker
shaped the dough into
7. Divide the dough into 16 balls about the size of a small orange. Push a
Ingredients
floured finger through the centre of one of the balls. Twirl the bagel around
a stirrup. The Austrian
word for stirrup is bagel.
The popularity of the
bagel spread throughout
Eastern Europe, evolving
as it did so into its
characteristic doughnut
225 ml milk, scalded
the finger on the work surface (think hula-hoop) until the hole is at least one
(i.e. boiled & hot)
third the diameter of the whole. Repeat for the other balls.
8. Place them on a tray and leave in a damp place. Dave uses a cake cooling
50 g butter
rack to support a wet tea towel over the dough balls.
25 g castor sugar
9. Leave them to rise until they look puffy, which can take as little as 10 or
15 minutes. Don’t wait too long – they should not double in size.
2 tsps dried yeast
shape. During the 1880s,
thousands
of
Eastern
10.Preheat the oven to 200 °C (Gas mark 6).
1/2 tsp salt
European Jews emigrated
to America taking with
them this unique type
of bread. Since then
11. Prepare a large shallow pan of gently boiling water.
White of 1 medium egg
12.Put the bagels into the water a few at a time so that they don’t touch one
400 g strong plain flour
another. They will float about halfway in and out of the water. Leave them
to rise for 15 or 20 seconds then lift them out with a slotted spoon, and
the bagel has grown in
arrange them onto a greased baking tray. They won’t rise much more than
popularity and is now
the size they are now.
a standard food item
on supermarket shelves
13. Bake for about 20 minutes, until they are golden brown and sound hollow
across the UK. What
makes
the
bagel
when you tap them.
so
14. Transfer to a baking rack to cool.
different from ordinary
bread is the cooking
process. It is the only
Extras
dough that is boiled
before it is baked. It is
Toppings like seeds can be added to the surface of the bagel prior to baking. The
this procedure that gives
dough can be sweetened by adding sugar to the flour. Different types of bagel
the bagel its unique
can be made by the addition of, for example, raisins to the basic dough after
texture and glossy crust.
kneading has taken place.
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Dave Roberts’ elderflower ‘champagne’
Method
Ingredients
1. Shake flower heads to remove any insects. The flower heads
2 large heads of fully open elderflowers
can be washed before use in cold water and then patted dry
on kitchen paper. Care must be taken not to bruise the flower
30 ml white wine vinegar
heads, as they are very delicate.
1 large lemon
2. Pick the florets from their stalks and put them into a suitable
680 g sugar
container, such as a plastic bucket with a loose-fitting lid. It
should have a capacity of at least 7 litres.
4.5 litres cold water
3. Thinly pare the lemon (no white pith) and cut up the parings
This recipe makes 5 litres
into fine particles.
4. Juice the lemon and add the parings and the juice to the
bucket.
5. Add the cold water and the vinegar, then stir in the sugar until
it has dissolved.
ELDERFLOWER
‘CHAMPAGNE’ –
6. Cover and leave in a warm place for 24 hours.
7. Strain the liquid and pour into suitable bottles, leaving a
50 mm gap.
an elegant, sparkling
fermented drink
NB: Suitable bottles are screw-topped 1 litre bottles that
previously held carbonated drinks, like tonic water, etc.
Avoid bottles with shoulders (like red wine bottles). If you use
glass bottles, they must be strong enough to withstand the
The fragrant flower heads from
pressure that will build up during fermentation.
the elder tree can be used to make
a refreshing summer drink called
8. Put the caps on tight and lay the bottles on their sides
elderflower ’champagne’. The elder is
somewhere where the temperature will stay reasonably
a common native tree found grow-
constant at around 21 °C. After 2 weeks, move them to a
ing in mixed deciduous woodland,
cool store. Serve cool, but not cold. Drink the elderflower
marshy woodland, thickets, clearings,
‘champagne’ within 4 weeks.
hedgerows and gardens. It flowers in
late spring, producing an off-white
NB: The bottles are laid on their side to minimize damage
flower, which grows to approximately
from flying bottle tops should the brew explode. Take care
5 to 6 mm in size. The best time to
when opening the bottles. You can take the top off under a
pick the flowers is on a dry warm
wet tea towel and you should at least open them over the
day when they are in full bloom. It is
sink. They have a tendency to be volcanic when first opened.
important that the flowers are not
collected from busy roadsides where
Microbiology
they may be exposed to air pollution.
The addition of yeast is not required
The fermentation of elderflower ‘champagne’ relies on the natural
as wild yeasts that occur naturally on
flora of the plant material, but Dave tells us that the yeasts in the
the flowers ferment the elderflower
sediment at the end of the process are not the same as the ones
‘champagne’.
that can be isolated from the flowers at the start.
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GINGER BEER –
a very refreshing, old-fashioned,
fermented drink
Ginger beer originated in England, in the mid-1700s, where it
became the favourite drink for over 150 years. The forerunners of
ginger beer were mead and metheglin (mead flavoured with herbs
or spices). Mead is a yeast-fermented honey and water drink and
has been around for a very long time. Records show that the Celts
were drinking it as long ago as 500 AD. It is reputed to be one of
the oldest recorded fermented beverages. Ginger beer also uses
home-baked bread. In
yeast for fermentation and is sweetened with honey, molasses or
England
cane sugar. The yeast converts the sugar into ethanol (alcohol)
the popularity of ginger
and carbon dioxide (gas). Other ingredients include fresh whole
beer peaked in 1935. The
ginger, although in Libby’s recipe this has been replaced with
USA had 300 breweries,
ground ginger and lemons or lemon juice. The yeast is also said
Canada had over 1,000
to add a special flavour to the beer, which is similar to that of
and England had 3,000!
Ingredients
25 g fresh yeast or
Libby Riley’s
ginger beer
and
Canada,
Method
Starter ‘plant’
15 g dried yeast
Put the yeast into a large clean jar. Pour in 275 ml warm water. Stir in 10 ml (2 tsps) sugar and 10 ml
(2 tsps) ground ginger. Cover and leave in a warm place for 24 hours. This is the starter ‘plant’.
1 kg sugar
Feeding the ‘plant’
40 ml (8 tsps) ground ginger
1. On each of the following 6 days, feed the ‘plant’ with 5 ml (1 tsp) sugar and 5 ml (1 tsp) ground ginger.
Juice of 2 lemons
Stir and cover the jar each time.
Water
2. After the last addition, leave the solution to stand covered for another 24 hours.
This recipe makes 5 litres
3. Line a sieve with muslin. Strain the solution, reserving both the liquid and the sediment.
4. Over a low heat, dissolve 900 g sugar in 575 ml water. Stir well.
5. When the sugar has dissolved, bring to the boil and boil for 3 minutes.
6. Pour the syrup into a large bowl and stir in the lemon juice and liquid from the ‘plant’.
7. Dilute with 3.5 litres water, stir well and pour into clean, rinsed out bottles. Secure the bottles with corks
(do not use screw tops as yeast produces carbon dioxide as it ferments the liquid which may cause the
bottles to explode).
8. Store for at least 1 week before using. Use half of the reserved sediment as the new ‘plant’ to start the
next batch of ginger beer. Give the other half to a friend so they can make their own.
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YOGHURT - a thick and creamy fermented dessert
Josiane Dunn’s
homemade yoghurt
Method
Yoghurt is a fermented milk product in which milk
is inoculated with a starter culture containing two
1. Heat the UHT milk to 43 °C. The
different types of lactic acid bacteria. The process of
lactic acid bacteria grow best at
yoghurt making has been around thousands of years
this temperature. Take care not to
and originated in the warm climate of Mesopotamia,
overheat or the bacteria will be the present day Middle Eastern country of Iraq, when
killed.
stored goat’s and sheep’s milk fermented naturally in
the high summer temperatures. The mixture was then
2. Add the starter culture and dried
hung in animal skins to cool. A soft curd called ‘jugurt’
milk powder. Mix well.
was formed. This is where the word yoghurt comes
3. Pour the mixture in to a pre-
from.
warmed wide necked vacuum flask.
Replace the lid and leave for 6-8
Today a starter culture of Streptococcus thermophilus
hours.
and Lactobacillus bulgaricus is normally used. As
the bacteria grow they use the milk sugar lactose as
4. Pour the yoghurt into a bowl and
an energy source and produce lactic acid. Initially,
cover with cling-film and place
Streptococcus thermophilus ferments the lactose; as
in a refrigerator for 4 hours. The
the level of acid accumulates, its growth is suppressed.
yoghurt will get even thicker
Lactobacillus bulgaricus, which is more acid- tolerant,
during this time. The yoghurt will
continues to ferment the remaining lactose. During
then be ready to eat.
this process the pH drops from 6.5 to around 4.5.
This inhibits the growth of spoilage microbes.
All containers and utensils must
be thoroughly cleaned before they
Consequently, yoghurt keeps well in the fridge for
are used to prevent contamination.
some days. The presence of lactic acid causes the
Once the yoghurt has been made it
structure of the milk protein to change; this gives
must be stored at 4 °C and eaten
yoghurt its special thickened texture. The lactic acid
with in 4 -5 days.
also gives the yoghurt its sharp taste. Other products
of the lactic acid fermentation, such as acetaldehyde,
give the yoghurt its characteristic smell.
The yoghurt can be flavoured with
fruit puree as preferred.
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23
Ingredients
575 ml UHT milk
(the use of UHT milk
removes the need to
sterilize the milk by
boiling it)
2 tbsps unpasteurized
natural yoghurt or
bio-yoghurt
2 tbsps dried milk
powder
A
MICROBIAL
MENU
QUORN® AND MUSHROOM STROGANOFF
Serves 4
Preparation time – 10 minutes
Cooking time – 25 minutes
Method
Ingredients
1. Slice the red onion into thin
2 tbsps oil
slices, crush the garlic and roughly
1 large red onion
chop the mushrooms – brown
cap mushrooms would be a good
2 cloves of garlic
choice.
350 g QUORN® pieces
2. Heat the oil in a frying pan, add
225 g MUSHROOMS
the onion, and garlic and cook
250 ml vegetable stock
over a medium heat for 5 minutes.
2 tsps smoked paprika
3. Add the Quorn® pieces, mushrooms and paprika and cook for
2 dsrtsps BRANDY (optional)
a further 5 minutes.
100 ml half fat CRÈME FRAICHE
4. Add the stock, brandy (optional),
Seasoning to taste
and cook for a further 10 minutes
Chopped fresh parsley and a
or until the liquid is reduced by
sprinkle of paprika for garnish
half.
The ingredients in bold are microbial
5. Stir in the crème fraiche and seasoning to taste and cook over a
medium heat for 5 minutes.
6. Garnish with chopped parsley and
a sprinkle of paprika.
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27
THAI
TOFU
COCONUT
CURRY
Ingredients
4 blocks of firm TOFU
2 bags of shredded coconut
2 tbsps each of DARK & LIGHT SOY SAUCE
4 tbsps FISH SAUCE
4 tins of coconut milk
4 onions
1 bulb of garlic
2 bags of carrots, peas and courgettes
Method
4 red peppers
1. Peel 2 onions and all the garlic, de-seed 4 red peppers and 3
red chillis (leave the seeds in the other 3), peel the ginger and
6 red chillis
crush the lemon grass. Place into a food processor and blend
1 bunch of lemon grass
to a paste.
1 thumb of ginger
2. Peel and slice the remaining onions and set aside for later.
1 pack of kaffir lime leaves
100 ml olive oil
3. Warm a large, flat-bottomed pan and add 100 ml olive oil.
When the oil is warm, add the paste from step 1, stirring
Sweet chilli sauce
constantly so that it doesn’t burn. When the paste becomes
The ingredients in bold are microbial.
less watery, add the sliced onions from step 2.
4. When the onions have taken on some colour, add the coconut
milk, 1 bag of shredded coconut and 3 kaffir lime leaves. Mix
Serves 3–4
Recipe supplied by Wayne Sullivan,
Montpellier Chapter Hotel, Cheltenham
thoroughly and bring to the boil. Reduce to a simmer and
Preparation time – 15 minutes
Cooking time – 45 minutes
allow the sauce to reduce by roughly half the volume (approx.
30 minutes).
5. Roughly dice (1–2 cm) the vegetables and the remaining
peppers. Do the same with the tofu.
6. When the curry sauce has reduced by half, check the
consistency. If it appears to be too thick, add some
more shredded coconut. Then add the diced vegetables,
peppers and tofu and allow to cook for a further 10
minutes.
7. Remove from the heat and add 2 tbsps each of dark and light
soy sauce, and 4 tbsps fish sauce. Sweet chilli sauce can be
added to taste. Season with a little salt, but not too much as
the soy and fish sauce are quite salty, and serve.
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ACKNOWLEDGEMENTS
IMAGE CREDITS
The Society for General Microbiology is the
Covers café menu iStockphoto (adapted I. Atherton)
largest microbiology society in Europe, and has
2–3
soy sauce iStockphoto | shiitake mushrooms iStockphoto | marmite Hemera | ice cream Valueline
4–5
yoghurt iStockphoto | sauerkraut Hemera | chorizo iStockphoto | pickles Photos.com | olives Photodisc
6–7
blue cheese Polka Dot | cheese rounds Antonia Reeve SPL | brie Photos.com |
over 5,000 members worldwide. An important
function of the Society is the promotion of the
public understanding of microbiology. The Society is
cheese selection Digital Vision
committed to raising awareness of microbiology and
the role of microbiologists to key audiences including
8–9
schools, parliamentarians, the media and the general
bread selection Stockbyte | bread in basket Photos.com | beer glass iStockphoto | beer bubbles
iStockphoto | fungal growth on grapes Dr Jeremy Burgess SPL | white wine iStockphoto
public.
10–11
melted chocolate Hemera | coffee beans Valueline | cocoa pods and beans iStockphoto |
coffee cup iStockphoto
SGM is grateful to Dr Anthony Hilton, Aston
University, for his invaluable help and suggestions in
12–13 white truffles Vision SPL | Quorn® Gustoimages SPL | orange slices Hemera
producing this resource.
14–15 cheese, grapes and wine Photos.com
16–17 bagels Hemera | stacked bagels Creatas
18–19 elderflower cordial iStockphoto | elderflowers Hemera
20–21 ginger root iStockphoto | ginger beer iStockphoto
22–23 yoghurt in dish iStockphoto | jar of yoghurt iStockphoto
We also thank Wayne Sullivan, Montpellier Chapter
24–25 set table Hemera
Hotel, for providing the Thai tofu coconut curry recipe.
26–27 mushrooms Goodshoot | garlic, parsley and red onion iStockphoto | paprika Hemera
28–29 lemon grass and chillis Hemera | tofu pieces iStockphoto | coconut Digital Vision |
Written byDariel Burdass SGM
lime leaves Hemera
Proofread by Laura Udakis SGM
30–31 cocoa beans and chocolate iStockphoto
Design & production Ian Atherton SGM
Printed by Making Impressions, Yateley, Hampshire
Every care has been taken to ensure that the
information provided this resource is correct, but the
author will be pleased to learn of any errors that have
remained undetected.
© 2011 Society for General Microbiology
Microbiology
society
for
general
30
31
All provided through Thinkstock except those marked SPL (Science Photo Library)
Microbiology
w w w. s g m . a c . u k
society
for
general
Marlborough House, Basingstoke Road
Spencers Wood, Reading RG7 1AG, UK
t 0118 988 1802; e [email protected]