Part 2 Flashcards
(29 cards)
What are the five sense perceived by the human?
- Sweet
- Umami
- Sour (Acid)
- Bitter
- Sat
Is there flavor in food?
No, is not present in food it is an interpretation that our brain performs when certain volatile compounds enter our nose/mouth.
What part of our body is responsible for processing the odors from food products?
Olfactory system
Explain the major key aspects of the olfactory system.
- Receptors for odor are olfactory cells
- These cells are long and narrow (<1 um in diameter)
- Olfactory cell are nerve cells
- There are 6-10 million of these cells
- Located in the olfactory epithelium, located in the upper part of the nasal cavities.
- Mucus layer that protects cells
- Olfactory cells have cilia which increase surface area
- Olfactory cell have nerve fibers on opposite side of cilia which transmit signal to brain
- Odor must be soluble in mucosa in order to transmit.
Taste buds are located within small, but
visible, structures known as papillae. What are the four type of papillae and which have a role in taste perception.
The four papillae are:
1. Fungiform
2. Foliate
3. Circumvallate
4. Filiform
All apart from foliate play a role in taste perception. Foliate is used for grip and mouthfeel sensation.
What are the five basic taste linked to?
Sweet -> sugar/carbs
Sour -> pH of food product
Salt -> alkali metals and halogens
Bitter -> poisonous
Umami -> monosodium glutamate and ribosides
What type of panelist, trained or untrained, do i require to conduct a analytical or affective sensory evaluation?
Analytical -> trained
Affective -> untrained
What are some tests that can be conducted to trained panelist and describe them (analytical sensory evaluation)? What is important to have good results?
- Basic Test -> panelist has to distinguish five taste from diluted concentrations in water.
- Intensity Test -> panelist has to rank intensity for increasing concentration.
- Triangle Test -> to remove the one that is off from three.
- Ability to describe food colors -> e.g. Blue-colored jelly with a strawberry flavor
- Odor recognition taste
Good approach, panelist must be motivated to reduce errors and careless feedback. Potentially reward mechanism.
What are some key factors that panelist and organizer must consider before conducting a panel testing?
- No eating spicy food before testing
- Wait 1h after meals and 30 min after snack/smoking
- If ill, cannot take part
How to code numbers on sample?
- Avoid repeating codes between different tests
- Avoid letter number combination, e.g. A1
- Avoid letter (e.g. A, B X)
- Avoid numbers that attract attention (e.g. 666, 999, 000)
If there is a difference in texture or appearance, how can the organizer mask this to avoid affecting sensory evaluation?
Change of lighting or special lightning
Should size of samples be the same? and how much?
Yes, enough for 3 sips and 2 bites and double if intended also for swallowing
Should panelist clean their palette between samples? and how?
Yes.
1. Water
2. Apple
3. Carrot
Should all the sample be presented immediately to the panelist?
No. This can make the panelist overwhelmed and by knowing how many there are it can influence the ratings and accuracy of their observations.
Can position affect choice in triangle test?
Yes, usually middle is removed
Why is the Tetrad method (difference method) better than triangle and duo methods?
Because more samples offered to the panelist lead to a reduced Type 1 and Type 2 error.
What is a difference method?
Involves determining the difference between two (Paired comparison) three (Triangle) or four (Tetrad) products.
What are descriptive methods?
Descriptive methods involve the training of
panellists to quantitatively determine the
sensory attributes in a sample or more usually
a selection of samples.
What are three disadvantages of descriptive methods?
- Time consuming
- Expensive
- Laborious
What are the difference between internal and external preference mapping?
Internal preference mapping focuses on the preference of consumers whiles external preference mapping focuses on understanding sensory information about the product and overlaying this information with consumer liking data
What is preference mapping?
Preference mapping techniques involve statistically relating external information about perceived product characteristics to consumer preference or acceptance ratings. To determine a product’s characteristics and obtain a better understanding of what attributes of a product are driving preferences
What is free sorting?
Panellist sort products according to similarities. No forcing, easy, panellist choses own criteria.
Napping can be used which involves a sheet where the products can be positioned and grouped.
What are some options of rapid profiling using References?
- Polarized sensory positioning (PSP) -> comapre similarity from same taste to completely different
- Off flavor quantification -> like PSP but for odors.
- Optimized sensory profile method
What is the check-all-that-apply method (CATA)?
Questionair like survey were panelist check boxes if satisfy question after trying product, Quick, qualitative data, question must be formulated good.
