The food lab better home cooking through science ( PDFDrive ) 498

Pasta,”here). On the other hand, the temperatures of the
potswithverylittlewaterdroppedmuchmoreprecipitously
when I added the beans to them. Not only did the beans
cooked in less water take longer to tenderize, they also
ended up cooking to a drab army green instead of the
brilliant shamrock green of those cooked in a gallon of
waterormore.

Tounderstandwhythisisthecase,let’stakealookatthe
outside of a green vegetable. Like all living matter,
vegetables are composed of many individual cells. With
vegetables, these cells are bound in place withpectin, a
glue-like carbohydrate-based molecule. Within vegetable
cells, there are various pigments, enzymes, and aromatic
compounds. Green vegetables in particular contain
chloroplasts, the tiny organelles (that’s a small organ)
responsible for converting sunlight into energy through the


use of the pigmentchlorophyll, which is responsible for
givinggreenvegetablestheirbrightgreencolor.
Between all of the plant cells are trapped tiny pockets of
gasesthatscatterlightwaves,partiallyobscuringyourview
of the vegetable’s bright green pigments. As soon as you
plungeitintoboilingwater,though,thosegasesescapeand
expand,andtheunhinderedviewofitspigmentsmakesthe
vegetableappearsuddenlymuchgreener.Atthesametime,
anenemyfromwithin—anenzymecalledchlorophyllase—
isworkingtodestroythevibrantgreencolorbyalteringthe
shape of the chlorophyll. Chlorophyllase is most active at
temperatures below 170°F, and it is destroyed at around

1 9 0 °F.That’s the reason why a large pot of water is
necessary.With a small pot of water, the vegetables spend
too much time under that 170°F cutoff, giving the
chlorophyllaseaheadstartindullingtheirappearance.With
largepotsofboilingwaterthatneverdropbelow190°F,the
chlorophyllaseisrapidlydestroyedbeforeithasachanceto
gettoworkonthechlorophyll.
Even with the cholorphyllase out of commission, a
boilinggreenvegetablewilleventuallybegintoturndrabas
heat causes irreversible changes in its structure. These
changes are exacerbated by acidic conditions—even a few
teaspoonsoflemonjuiceorvinegarinalargepotofboiling
water can cause green vegetables to rapidly turn dull when
cooked in it. This is the second reason why vegetables
should be cooked in plenty of water. As they cook, they
release their naturally acidic contents into the cooking
medium, acidifying it and hastening browning. Using a
large volume of water dilutes this acidity. Similarly,