TASTE

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TASTE
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IMPORTANCE OF TASTING AND SMELLING

• Protection
• Taste vomiting is not always an option
• Odor advanced warning (e.g., fire)
• Diet
• Omnivores must be able to taste and smell a
  variety of potential foods.
• Pleasure
• Motivation to eat.

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TASTE

• Taste occurs at the...
• tongue
• lips (in babies)
• soft palate
• epiglottis
• The primary unit of taste is the tastebud

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TASTEBUDS

• Modified epithelial cells--approx. 10,000
• Lifespan of 10 days
• Found in papillae

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DO TASTE PRIMARIES EXIST?
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THE TASTE PRIMARIES

• Saltiness NaCl, KCl, LiCl
• Sourness organic, inorganic acids
• Bitterness alkali and alkaloids
• Sweetness sugars, some amino acids proteins
• Umami MSG

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Tastes Satisfaction of Ancient Longings and
Needs
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Tastebuds
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Supertasters
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THRESHOLDS

• A function of receptors, neurons or higher levels
  of processing
• With regards to thresholds, no person is like
  another

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FACTORS THAT CHANGE THRESHOLDS

• AGE by age 75, you lose 2/3 of the tastebuds
  you had at 30
• TEMPERATURE physiological temp. is optimal
• SMOKING effects are temporary
• NUMBER OF RECEPTORS some people have more

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TYPES OF THRESHOLDS

• Absolute
• vision single candle metaphor
• taste detection of sugar in water
• Recognition (identification)
• females are better at it than males
• Difference
• the JND--just noticeable difference

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CULINARY APPLICATION OF THRESHOLDS

• Hollandaise sauce example
• add enough lemon juice that it is recognized
• add only enough cayenne to be detectable
• Good cuisine
• many flavors should be subtle that is, past the
  absolute threshold but not past the recognition
  threshold

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TASTE PHENOMENA

• mixture suppression
• wine and salad
• adaptation
• Coca-cola first and last sips
• modification
• artichokes, miracle berry
• potentiation
• MSG, 5 -nucleotides

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USE OF TASTES TO INCREASE FLAVOR

• Salt enhances flavor
• Sugar is used to increase fruit flavor
• Bitterness acts as a foil to sweetness
• Sugar and acids are mutually suppressive
  (Sugar-acid ratio)

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CHEMICAL SENSES AND TASTE

• Capsaicin.................
• Piperine....................
• Zingiberone..............
• Sinigrin.....................
• Menthol....................
• Carbon dioxide.........

• Chili peppers
• Piper nigrum
• ginger
• mustard, radishes
• mint family
• soft drinks, carbonated water

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HOW IS PAIN SENSED?

• Woe to the cook whose sauce has no sting.
  Chaucer
• The filiform papillae have nerve endings
  sensitive to pain and temperature.
• Pain-sensing neurons use substance P as a
  neurotransmitter. Continual firing depletes
  substance P, reducing pain.
• This leads to a partial state of euphoria.

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INTEGRATION OF TASTE SENSATIONS

• unlike colors, there is no fusion or melding of
  sensations--at least not at the level of the
  sensory receptors

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OTHER TASTES

• Temperature
• Somatosensory sensations

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GUSTATION AND OLFACTION

• Gustation taste. Gustare--to taste
• Olfaction smell. Olfacere--to smell

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MICROELECTRODE RECORDING

• The labeled line theory
• Problem with finding subjects
• Carl Pfaffmans work with cats
• exposed Chorda tympani found no sweet fibers
• hypothesized that there is a firing
  pattern--gtfiring pattern theory

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LABELED LINE THEORY--EVIDENCE
CON
PRO

• Single neuron more responsive to single taste
  primary.
• Receptors connected to the same fiber have
  similar sensitivities

• A single fiber can be connected to several taste
  receptors
• No detectable code responsive to sensory changes

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PROJECTION TO BRAIN

• Taste signals fork to
• parietal cortex (like visual cortex). Partly
  responsible fo Identification, recognition, and
  memory of tastes.
• limbic system (processing of emotions). Hedonic
  reactions.
• Both cortex and limbic system are involved in
  i.d., recognition and memory

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