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Unit 1 The Science of Food
red, blue, or green. Value is the lightness or darkness of the color.
Pink is a light value of red, while burgundy is a dark value. Chroma
is how intense the color is. Overcooked green beans become olive
colored, which is a dull or low intensity of green. A lime has a
bright or high intensity of green. With a colorimeter, the color of a
product can be defi ned in numerical values. A new food product’s
color can then be described to distant manufacturing plants without
sending samples. A year later, the color can also be compared with
the next production run.
Color can infl uence a person’s perception of other sensory
characteristics. For instance, you might think a dark brown chocolate
bar has a richer fl avor than a light brown bar. When researchers do
not want color to infl uence a taste panel, they use colored lights.
Researchers may test chocolate bars fi rst under red lights and then
under green lights. This will help the researchers study the impact
of fl avor and texture differences more accurately. Taste testing rooms
are equipped with various colored lights that can be used during a
sensory evaluation. See 3-5.
Flavor
Flavor is the combined effect of taste and aroma. Taste starts
in the mouth with the taste buds on the tongue. Each region of the
tongue is designed to respond to one type of taste. The fi ve basic tastes
are salty, bitter, sour, sweet, and savory. Each food will stimulate a
combination of taste regions on the tongue. Sweet and sour sauce is
a good example of how a food can be a combination of tastes.
Research indicates that a food’s taste is related to the shape of
molecules in the food. These molecules bind to the taste bud. For
example, a molecular shape that triggers sweetness has been identifi ed.
Suppose a molecule of a food matches up to a “sweetness” taste bud.
This will cause nerve endings to begin sending messages to the brain.
The brain knows that when nerve impulses come from that part of
the tongue, the food is sweet. The more taste buds a food stimulates,
the sweeter the food is perceived to be.
Janet Ward
3-5 Numbering samples and using colored lights help eliminate taste tester bias based on the identity and appearance of
food samples.