1. Introduction to sensory and consumer science

Question 1

What is the main focus of sensory science?

Answer 1

It focuses on finding out the relationship between physical stimuli and human perception (5 senses).

Example
- Physical stimuli : sucrose concentration
- Human perception : perception of sweetness by panellists (by giving sweetness intensity scores to products)

Sensory science : more quantitative (but also have qualitative aspects), science-driven

Question 2

What is the main focus of consumer science?

Answer 2

It focuses on consumer attitudes toward food products and how consumers make food choices when having a variety of products to choose from (focus on behavioural / psychological aspects of consumers)
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- thus, consumer science can be applied to products other than food (e.g. skincare, electronics…)

Sensory science : more qualitative, human-driven (humanities)

Question 3

Sensory science

What are the 4 main steps in sensory science?

Answer 3

1) Evoke : “How do we taste a food / beverage”?
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2) Measure : collect quantitative / qualitative data to establish relationships between stimuli and sensation

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3) Analyse : analyse the data collected, and determine if there is statistical significance
- statistically significance means products are different

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4) Interpret : Make sense of data in the context of established hypothesis (e.g. in hypothesis testing, after analysing your data, do you reject the null hypothesis?)

Question 4

What is the main purpose of discrimination tests? (What is the main research question?)

Is it an analytical or hedonic test?

Answer 4

• Purpose : to understand if the products are perceptibly different (i.e. if a small difference exists or not)

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- Main research question : Is there a difference between products A and B?

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- It is an analytical test

Question 5

Maybe can add this question into later deck

Is it useful to conduct discrimination tests for samples that have very large and obvious differences?

Answer 5

No, not useful. If the difference is very large, a difference can definitely be detected. Thus, discrimination testing is only useful when products have subtle differences, which may or may not be detected.

Question 6

What is the main purpose of descriptive tests? (What is the main research question?)

Is it an analytical or hedonic test?

Answer 6

• Purpose : to obtain understanding of sensory profiles of foods (linked to 5 senses : sound, taste etc)

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- Main research question : (if there is a difference), How / in what ways are products different from each other?

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- It is an analytical test

Question 7

What is the main purpose of affective tests? (What is the main research question?)

Is it an analytical or hedonic test?

Answer 7

• Purpose : focuses on consumer liking and / or preference of a product over the others (preference in terms of overall liking / focus on a specific property / attribute)

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- Main research question : Which product is most liked / preferred?

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- It is an hedonic test

Question 8

What is the difference between the data generated by hedonic and analytical test?

Answer 8

Analytical tests generate unbiased, objective data about a product’s sensory properties (product-focused)

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Hedonic tests provide subjective data about a product’s likeability, acceptablity and preference (consumer-based).

Question 9

Sensory testing can be conducted with humans, or machines such as electronic noses to detect concentration of aroma compounds etc.
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Why will a machine be preferred in determining the sensory characteristics of food products?

Answer 9

Machines are more reliable, results are more reproducible every time the same food sample is put in the same machine.

Question 10

For determining sensory characteristics of food, why are the results from humans not as reproducible as machines? [3]

Answer 10

1. For the same person, human senses may change with varying physiological conditions over time (ageing, sick)
2. There is varitation among individual human tasters
3. Human are prone to psychological biases

Thus, for descriptive analysis, a trained panel is used to generate highly precise (all panellists give similar rating score) / reproducible (each panellist generate similar intensity rating in different tasting session) and unbiased data.

Question 11

However, for determining For determining sensory characteristics of food, why are humans sometimes preferred over machines? [2]

Answer 11

1) Humans can detect complex interactions (cross-modal interaction where different senses interact to give a different perception)

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2) Humans are able to talk, and can describe sensory characteristics and just easier to talk to humans if researcher needs more info.

Question 12

What

Question 13

What is sensory transduction?

Answer 13

Conversion of 1 type of sensory data nto another (where body interacts with stimuli to give a response).

Question 14

What are the 4 steps involved in sensory transduction?

Answer 14

1) Stimuli : stimuli is perceived with the 5 senses.
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2) Neural response / sensory transduction: A signal is sent to the brain via the central nervous system
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3) Perception : brain recognises the stimuli

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4) Behavioural response : intepretation of perception by the brain, and response

omg intro to psych flashbacks..

Question 15

What are the 5 main senses involved in sensory perception?

Answer 15

1. Sight (appearance)
2. Odour (smell)
3. Taste
4. Touch
5. Hearing

Question 16

What are the 3 different kinds of “touch” in sensory perception of foods? Give examples

Answer 16

1) Trigeminal - pain / hardness receptors (sensations such as spicy foods, or cooling sensation from menthol)

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2) Pressure - tactile - perception of force exerted on the skin or mucous membranes when food comes into contact with them (e.g. firmness of foods - hard vs soft, crunchiness of chips)
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3) Kinaesthesis - related to food texture , how food feels when we chew and manipulate food in our mouths (e.g. visocity, temperature, astringency).

Question 17

Flavour of foods is shaped by which 3 sensations?

Answer 17

1. Odour
2. Taste
3. Trigenimal touch

Question 18

What are the 5 basic tastes?

Answer 18

1. Sweet
2. Salty
3. Sour
4. Bitter
5. Umami

Spiciness is not a taste!

Question 20

What is the difference betwee orthonasal and retronasal odour perception?

Answer 20

• Orthonasal :Aroma molecules (odourants) enter cavity during sniffing / smelling, enter directly through nose
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• Retronasal : aroma molecules released upon chewing and travels from back of throat up to nasal passages.

Question 21

Sensory perception : sight – appearance

TfThe perceived colour of an food object can be affected by what 3 factors?

Answer 21

1. Physical and chemical composition of object
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2. Spectral composition of light source that is illuminating / shining on object (aka the wavelength of light, different wavelength = different colour depending on which colours are emitted and absorbed. But for irl, it is the full spectrum of light, thats why we can see all colours)
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3. Spectral sensitivity of viewer’s eyes - e.g. colourblind people cant see at certain wavelengths, can only see a few selecteed colours

Question 22

In which 3 dimensions does colour vary?

Answer 22

1. Hue (the colour itself)
2. Saturation (purity / chroma of colour ; intensity)
3. Lightness (brightness)