How the Sense of Taste Works

HOW THE SENSE OF TASTE WORKS

Humans are born with the ability to taste. The sense of taste begins with the tongue. The skin over this muscular organ located inside the mouth is covered with about 10,000 receptor cells, or chemical-sensing bodies. These are called taste buds. Each of these funnel-shaped clusters has an opening called a taste pore. Molecules (small particles) of dissolved substances, containing chemicals, flow into these holes and trigger, or activate, a receptor cell.

The taste buds also respond to other stimuli. When people smell or think of a food they like, their mouth starts to water. This means that people start to produce saliva. In order for humans to actually taste something, it has to be dissolved in saliva. Like smell (called olfaction), taste (also called gustation) operates on the principle of chemoreception. Certain receptors are triggered when chemicals contact them. It was once thought that certain parts of the tongue responded only to one of the four basic categories or sensations of taste (sweet, sour, bitter, salty). Now it is thought that individual receptors are not specifically sensitive to only one sensation.

Unless the brain is involved in this process, a person will not be able to actually identify anything he or she has dissolved on the tongue. Science still does not know exactly how this occurs. Somehow, when a dissolved molecule triggers a taste bud, or cell, certain nerves at the root of the cell are also stimulated. These carry impulses to the brain stem, then to the thalamus or the front of the brain stem. The impulses finally end up in the cerebral cortex of the brain, the brain's taste control center. The brain interprets this signal, or impulse, and tells people what they are tasting. As with each of the senses, all of this happens instantaneously."

Science of Jelly Beans

Jelly beans come in many flavours and colors. Jelly beans are a popular candy worldwide. They were just a common penny candy until the 1930s when their egg-like shape linked them with the Easter tradition of giving out eggs as symbols of the new growth and life associated with spring.

Ingredients: Sugar, corn syrup, cornstarch and flavourings make up jelly beans. Gourmet jelly beans have flavourings in the jelly center as well as in the outer shell. Regular jelly beans carry all their flavouring in their outer covering.

Center: A jelly bean takes between six and 10 days to make. The corn syrup and sugar are mixed and piped into molds dusted with cornstarch to make the jelly centers. After drying overnight, the cornstarch is sprayed off the centers. The candies are moisturized with water, sprayed with sugar and left to dry for another 24 to 48 hours.

Shell: After the centers are set, they are put into drums that rotate as sugar, flavorings and coloring are slowly added to create the jelly bean shell. A light, clear glaze of sugar put into the drum makes the surfaces shiny. They are packed and shipped after being polished and shined for two to four days.

Do Our Other Senses Affect Taste? Testing if other senses affect out sense of taste is a fascinating experiment. You need to collect several jelly beans of the same flavor. You will start out blindfolded. Someone must pick up a jellybean, and feed it to you. Hold your nose closed while you chew the jelly bean. What did it taste like? Have someone write down your response. Have the same person feed you the same flavor jelly bean again. This time, don't pinch your nose closed. Did the taste change? Remove the blindfold and feed the same flavor jelly bean to yourself. Does the color of the jellybean affect the taste?

Trial My prediction of the flavour The correct flavour Were you correct? was: Yes/No? 1

Percent of trials you answered correctly: ______x 100 = 5