what are food flavours?
- sensations elicited by the food materials in the mouth and the nasal cavity
what are the 3 components of food flavor?
what is taste?
Is sensed by taste buds located on the tongue
what is door/smell?
Is detected by the olfactory epithelium in the nasal cavity
what is mouthfeel?
- The way that food feels in the mouth
- Has various compounds such as pain, temperature (hot, cold, warm) and tactile compounds
what is the mechanism of flavour perception?
- Components/compounds eliciting the various flavour sensations interact with receptors located in the mouth and nasal cavity
- As a result of these interactions , responses are sent to the CNS where they are translated into the different flavour sensations that are perceived
what are the 5 taste sensations?
- 1. Sweet
- 2. Sour
- 3. Salty
- 4. Bitter
- 5. Umami/Savory
Where is sweet taste percieved?
Mostly located at the tip of the tongue
Where is salty taste percieved?
To the front sides of the tongue
Where is sour taste percieved?
To the back sides of the tongue
Where is bitter taste percieved?
At the back of the tongue
How do we percieve smell in the mouth?
We percieve in the olfactory epitelium which is in the upper palate of the mouth
What is mouthfeel?
The way the food feels in the mouth and is sensed by the jaws and teeth
How is taste percieved by the brain?
- Molecules in food interact with taste receptors in the mouth and as a result of the interactions,
- Signals are sent to the central nervous system (CNS) where they are translated into the different flavor sensations we percieve
What is responsible for the sweet taste in foods?
- Due to electronegative elements of organic molecules (organic compounds have O or N atoms)
- An atom that is electronegative has a high tendency to attract electrons
- Ex. alcohols (glycerol, xylitol), aldehydes (cinnamic aldehyde), certain amino acids (D-histidine)
How does enantiomerism effect the sweetness of amino acids?
D-amino acids tend to be sweeter than other amino acids
How is the relative sweetness of sugars measured?
is assigned an arbitrary number of 1
and other sugars are compared with sucrose on a scale known as the Relative Sweetness Scale
Describe the tastes of L- and D-Asp-NH2
- L-Asp-NH2 is tasteless
- D-Asp-NH2 is sweet
Describe the tastes of L- and D-glutamic acid
- L-glu is meaty
- D-glu is tasteless
Describe the tastes of L- and D-histidine
- L-His is tasteless to bitter
- D-His is sweet
Describe the tastes of L- and D-isoleucine
- L-Ile is bitter
- D-Ile is sweet
Describe the tastes of L- and D-tryptophan
- L-Try is bitter
- D-Try is very sweet
why is fructose sweeter than glucose?***
- The structure of the molecules say that the hydroxy group (OH-) separate
- More interaction between the hydroxy group (OH-) and the receptors for the fructose than glucose
what are some examples of traditional sweetners?
- Sucrose: disaccharide of fructose + glucose
- Honey: glucose + fructose + water
- Corn syrup: hydrolyse corn starch with hydrolase or amylase
- Invert sugar: sucrose/inverted, to break down you use invertase/hydrolysys?
- Maple syrup: glucose , fructose, H20, caramel, MRP
- High fructose corn syrup
- Molasses: thick dark viscous liquid residue after sucrose has been recovered from the sugar cane (glucose, fructose, sucrose, H2O phenolic compounds)
What is today's challenge regarding sweeteners?
- Today's challenge is to provide good tasting sugar-free products (low calorie, non-carcinogenic sweeteners)
- Examples either in use or approved for food use include - polyols (xylitol, mannitol, sorbitol, maltitol, lactitol); polydextrose, fruit juices.
What is the criteria for selecting alternate sweeteners?
- Sweetness equivalent
- Laxitive effect
- Heat of solution