22 February 2020 | New Scientist | 51SHROVE Tuesday, which this year
falls on 25 February, is marked
in some countries by making
pancakes. At their simplest, they
use a batter of flour, eggs and
milk. This works well for thin,
crepe-style pancakes. But I’m
going to make fluffy US-style
pancakes, which need a thicker
batter – and bubbles.
As pancakes cook, starch
granules in the flour absorb water,
swell and burst. Starch molecules
stick to each other, turning the
batter into a soft solid. Flour also
contains proteins that, in the
presence of water, link together
in a network of long chains. We
call this gluten. Along with egg
proteins, gluten contributes to the
structure of a pancake. But unlike
a bread dough, we want to limit
gluten development in the batter
to keep the texture of the pancake
tender rather than chewy. That is
why it should be made quickly,
with minimal stirring.
Baking powder is one way to
produce bubbles. It contains an
alkali – sodium bicarbonate (or
bicarb) – along with an acid
(usually potassium bitartrate) and
some starch to absorb moisture.
Add liquid, and the acid and alkali
can react together, producing
carbon dioxide. The reaction is
helped along by heat when the
batter hits the frying pan. Batters
containing baking powder should
be cooked straight away, otherwise
the gas will escape before cooking.
Alternatively, you can include
acidic ingredients, such as
buttermilk or sour cream, then
add sodium bicarbonate, eitherinstead of or as well as baking
powder – in this recipe we add
both. If you don’t have buttermilk,
you can substitute it with ordinary
milk with a tablespoon of lemon
juice for every 250 millilitres.
The batter’s pH also influences
how quickly the pancake browns
as it cooks. We encountered this
principle in an earlier column
when caramelising onions. In
pancakes, too, alkaline conditions
speed up the Maillard reactions
between amino acids and sugars
that give us the brown colour and
delicious flavour we’re looking for.
In his book The Food Lab, J. Kenji
López-Alt demonstrates this by
cooking five batches of pancakes
with different amounts of bicarb.
The more there is, the darker theresulting pancake. If you see dark
spots on the pancake, it might
mean the bicarb needs mixing
more thoroughly into the batter.
To make my pancakes, mix all
the dry ingredients together. In
another bowl, beat the eggs and
add the buttermilk and melted
butter. Then mix the two together
and drop a ladleful into a lightly
oiled pan on a medium heat. Cook
until nicely browned on both
sides, and serve with maple syrup.
If you add blueberries to the
batter and they turn green, your
mix is too alkaline. Anthocyanin
and related pigments in fruit are
sensitive to pH and change colour
in alkaline environments (for
more on these fruit pigments
see Almost the last word, page 54). ❚Texture, bubbles and browning: Sam Wong uncovers
the science of perfect pancakesPuzzles
A cryptic crossword,
plus the quick quiz
and puzzle p52Feedback
A case of nominative
contradeterminism:
the week in weird p53Almost the last word
Mulberry juice stains
and cold fingers:
readers respond p54The Q&A
Elisabeth Bik, science
sleuth, on research
and cheating p56Twisteddoodles
for New Scientist
A cartoonist’s take
on the world p53The back pages
JAMES
WINSPEARSam Wong is social media
editor at New Scientist.
Follow him @samwong1
Science of cooking Week 8
Make a better batter
Science of cooking online
All projects are posted at
newscientist.com/cooking Email: [email protected]What you need
300 grams plain flour
1 teaspoon of baking powder
Half a teaspoon of sodium
bicarbonate
1 teaspoon of salt
1 tablespoon of sugar
2 eggs
600 millilitres buttermilk
60 grams melted butter
Maple syrup
For next week
Large jar
Cabbage
Spring onion
Salt, garlic, ginger, chilli
Next in the series
1 Caramelising onions
2 Making cheese
3 Science of crispiness
4 Tofu and Sichuan pepper
5 Gravlax and curing
6 Tempering chocolate
7 Umami and flavour
8 Perfect pancakes
9 Kimchi/fermentation
Create a tasty
microbial ecosystem
10 Sourdough bread