Enabling Innovation Getting Started With Sensory Evaluation - University of Nottingham

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Enabling Innovation Getting Started With Sensory Evaluation - University of Nottingham
Enabling
  Innovation

Getting Started
 With Sensory
  Evaluation
Enabling Innovation Getting Started With Sensory Evaluation - University of Nottingham
Introduction

                    I want to do some sensory….

               What do you want to find out ?

               What will you use data for?

               What actions will you take in response to data?
Enabling Innovation Getting Started With Sensory Evaluation - University of Nottingham
Introduction
     SUBJECTIVE
Opinions                                    Sight

Preferences
Expectations                                Aromas

     SENSORY                                Mouthfeel
    RESPONSES                                   &

   OBJECTIVE                                   Trigeminal
Differences /similarities   Sound   Taste      sensations

Descriptions
Intensity
Enabling Innovation Getting Started With Sensory Evaluation - University of Nottingham
CONSUMERS
                                                         What are consumer
                                                         Focus   group
                                                           expectations?                                     Benchmarking
                                                                                                           How does my product taste
                                                                                                               compared to the
                                             Market awareness / competitor analysis                                 Test
                                                                                                                 competition?
             Which does the consumer
              Preference
                     prefer? Tests
                                                                                                        Which does the consumer
                                                                                                         Preference
                                                                                                                prefer? Tests
New Product Development                                                                             Existing Product
                                                 Shelf life determination
(NPD)                                                                                               Development (EPD)
                                                       Discrimination
                                                      How long before it tastes
   Does the consumer like this                                                                          Can people notice the change
    Acceptance     Tests
     ? And by how much   ?
                                                             different?
                                                      /Descriptive Tests                                Discrimination
                                                                                                                  made?
                                                                                                                             Tests
                                                       FACTORY
                                                       FACTORY
                                                                                            Product Sensory spec

 Purchasing                        Goods in                     Manufacturing process                                 Process
                Raw material spec: Sensory
                      parameters                                                                                      Control

                                                                                  Storage
                                                                                                              How is my product
    Quality Monitoring (QA / QC)                                                                            Descriptive      Test
                                                                                                            effected by the supply
                                                                                                              chain? ‘Buy backs’
                Product Sensory spec                                               Sales
                                                                                                             Customer Sensory spec
           Discrimination
           Is it consistent to last Tests
                                    batch?
                                                                                                         How to use sensory as a
                                                                             Marketing                    Descriptive
                                                                                                             selling pointTest
                                                                                                                          ?
            How is it different? Informs
             Descriptive       Tests
              root cause analysis.
               Difference
           Is this             fromHold
                   adequate quality?
                 / control   tests
                   release decisions.                 CONSUMERS
                                                      CONSUMERS                                          Label descriptions /advertising
Research & Controlled Studies
Sensory evaluation for SMEs – market awareness

Benchmarking posh
chocolates - Christmas
Market:
Sensory evaluation for SMEs – sorting based on sensory profile

                                             Cider “Napping” –
                                             Dad’s Dining Room
                                             Table
Sensory evaluation for SMEs – looking for a difference

Discrimination Test, Apple Juice - Bramley
Apple Festival Southwell Minister
Sensory evaluation for SMEs – checking there’s no difference

Triangle Test, Botanical
Extracts –

At a grower / supplier’s farm office,
Hungary
Sensory evaluation for SMEs – Descriptive Profile & Ranking Test

                             Part 1: Beer Profiling
                             – Pub in Derby (local
                                     beer drinkers)

Part 2: Beer Ranking
– My Dining Room
Table!
Practical – Basic Taste Recognition

You will taste solutions of the basic tastes using store cupboard
ingredients.

Do not contain:
• any of the official allergens as listed in 1169/2011
• alcohol

Vegan and vegetarian-friendly.

IF THERE IS ANYTHING ELSE YOU DON’T WANT TO CONSUME
TELL ME NOW …
Basic Tastes - Recognition Test

Answers

 658      Sour/acidic/tart – citric acid at 0.5%

 705
          Water control

 319      Sweet – sugar/sucrose at 2%

 548      Salty – table salt / sodium chloride at 0.5 %

 536      Water control

 310      Bitter - Tonic water at 10% (quinine) also some sweet & acid
Discrimination Tests – THE TRIANGLE TEST

Scenario: Artisan drink

Production Manager: “I can make an efficiency saving by changing the process”.

Owner:               “Great, but won’t that affect the flavour of the drink…. ?”

Technical Manager: “The difference from trial runs is certainly not that huge…”
Golden Rules for Sensory

PEOPLE:

1. Use a group of people to make sensory assessments.

2. Be aware of individual differences in detection / perception.

3. Avoid coffee, mouth wash and smoking 2 hours before assessment.

4. Use palate cleansers:      Samples type tested                               Palate cleanser
                              Most products                                     Still, unchlorinated water (not mineral water).
  (and leave time to palate   Products with strong flavours or tastes           + Plain crackers/ water biscuits. Unflavoured,
   cleanse).                  that might persist                                no salt.
                              e.g.: beer bitterness / spicy food /
                              artificial sweeteners                             For spicy food – milk.
6. Don’t do too many
   samples / have breaks.     Fatty /creamy / oily products                     Slice bland apple (e.g: Gala)

                              Products high in astringency
7. Due diligence –                                                              0.1% pectin solution
                              e.g.: tea (other products high in polyphenols –
   food safety.               cider, rhubarb, cranberry juice)                  Piece of melon
Golden Rules for Sensory

SAMPLES

4. CONSISTENT – size / shape / format / sample container / temperature

5. REPRESENTATIVE of batch / product

ENVIRONMENT

6. Avoid distraction
         odours
         conferring

7. Get out of factory wherever possible.
Golden Rules for Sensory - Sample Presentation

Triangle Test:

                  Create your own Random 3 digit numbers in
                  Excel:
                           =RANDBETWEEN(1,999)
Golden Rules for Sensory - Sample Presentation

Labelling is inconsistent, draws attention to one sample.
Golden Rules for Sensory - Sample Presentation

Again different manner of labelling - font, colour, number of digits.
Golden Rules for Sensory - Sample Presentation

Different sample sizes – bias / not enough to evaluate for some
             samples, too much to drink in others.
Golden Rules for Sensory - Sample Presentation
Golden Rules for Sensory - Sample Presentation

                                          Same cups

                                          Same labels

                                          Same label position

                                          3 digit random codes

                                          All contain same amount:
                                          30ml.
Practical – Triangle Test

Does not contain:
• any of the official allergens as listed in 1169/2011
• alcohol

Vegan and vegetarian-friendly.
Discrimination Tests – THE TRIANGLE TEST
• Often called a DISCRIMINATION / OVERALL DIFFERENCE TEST.

• “In general (using all senses) can you tell a difference between 2 samples”.

• Common situations: INGREDIENT CHANGE.          PROCESS CHANGE.

• Allows you to declare if the samples are SIGNIFICANTLY DIFFERENT or not.

• Does NOT allow you to say the samples are ‘SIMILAR’ where a significant
  difference is found.

• Typically you have already determined that the samples pretty close in profile
  and you want some data to decide one way or the other.

• Good number of people to use: 24 – 30 (most balanced : nos. divisible by 6)
Discrimination Tests – THE TRIANGLE TEST: Set up

• BALANCED DESIGN reduces bias.

• 6 possible orders of presentation:
                                          A A B                 B B A
                                          A B A                 B A B
  where A = test sample
        B = control sample                B A A                 A B B
• BEST PRATICE:

  Give first 6 people one each of the above; then repeat each presentation
  order an equal number of times.

• Get organised – make a plan….
Discrimination Tests – THE TRIANGLE TEST: Results Analysis

                                                  Number of respondents from your test   Number of people needed to correctly
                                                                                         identify the different sample in order to

Critical Value Table for Triangle Test Data                                              declare a significant difference (p =
                                                                                         0.05; 95% confidence level)

Analysis                                                           6
                                                                   7
                                                                                                            5
                                                                                                            5

Data source: BS ISO 4120:2004 Triangle Test                        8
                                                                   9
                                                                                                            6
                                                                                                            6
                                                                   10                                       7
                                                                   11                                       7
                                                                   12                                       8
                                                                   13                                       8
                                                                   14                                       9

95% confidence level
                                                                   15                                       9
                                                                   16                                       9
                                                                   17                                       10

• Typical for food industry sensory                                18
                                                                   19
                                                                                                            10
                                                                                                            11
                                                                   20                                       11
                                                                   21                                       12
                                                                   22                                       12

• Only a 5% risk that you wrongly conclude the                     23
                                                                   24
                                                                                                            12
                                                                                                            13

  samples are different.
                                                                   25                                       13
                                                                   26                                       14
                                                                   27                                       14

                       or                                          28
                                                                   29
                                                                                                            15
                                                                                                            15

   You are 95% confident of the conclusion from
                                                                   30                                       15
                                                                   31                                       16
                                                                   32                                       16

    the test.                                                      33
                                                                   34
                                                                                                            17
                                                                                                            17
                                                                   35                                       17
                                                                   36                                       18
                                                                   …                                        …
Discrimination Tests – A SME Difference from Control Test

                                          Ø QA during production

                                  }
IS THE PRODUCT / RAW MATERIAL
‘IN SPECIFICATION’ ?                        - e.g: raw materials /
                                             intermediates
IS THE PRODUCT / RAW                          …preventative
MATERIAL CONSISTENT WITH
PREVIOUS BATCHES?                         Ø QC finished product
                                            …hold / release decision
IS THERE A DETECTABLE FAULT?
                                          Ø Shelf – life testing NPD /
                                            EPD
IS THE PRODUCT STILL RECOGNISABLE /         …determine BBE
REPRESENTATIVE OF BRAND?                  Ø Buy back testing
                                            ….QC once in supply chain
                                            …pick up misuse / abuse
Discrimination Tests – A SME Difference from Control Test

Control / Reference Point                          Test samples

     Brand std.
     Sample
                                                                       ….
                                People – know product well / trained
        OR

                  Documented
                  Standard

                  - Spec.
                  - QAS
                  - Photos
Discrimination Tests – A SME Difference from Control Test – Set up

A scoring system : assesses & decision making

   IN SPECIFICATION          ACCEPTABLE             OUT OF SPECIFICATION

                                                      Taint
Sensory                   Profile                     Off flavour
profile                   close but
matches                   some                        Different
control                   variation                   profile
       RELEASE                 RELEASE                            REJECT

                                                Root Cause Analysis
PRACTICAL – Basic Different from Control Test

Scenario: Daily QA Taste Panel in Brewery
Sample ingredient list:

Water, BARLEY malt, rice, hops.                4.8% ABV

• Remember to include Hidden Controls sometimes.

                        Ø Validates Method
                        Ø Validates Panel Ability

• Include a space for descriptive comment.
• Can develop a number of scales for key attributes.
Discrimination Tests – summary

• Are OBJECTIVE TESTs – no opinions / emotions involved!

• Who ? People from the company.

• Triangle Test is a commonly used overall difference test when you have 2
  samples to test for general differences.

• Difference from Control Test is commonly used in QA/QC. Compare multiple
  samples to a reference (specification/control sample) for overall difference.

• Paired Comparison Test is used for a specific attribute test when you have 2
  samples to test for a difference in specific attribute (eg: which sample is
  sweeter?).

• Ranking Test is used to test for difference of specific attribute test when there
  are 3 or more samples.
Consumer Testing - PRACTICAL

Scenario: Acceptance test – Cloudy premium apple juice

      I’ve just inherited an orchard, there are loads of apples, I’ve had some juice
      made. I think it tastes wonderful! I’m going to start a business…

      1) Do consumers like the taste of my new juice? Why ? and by how much?

      2) Is it sweet enough for them ? (I could store the fruit, press later; make it sweeter)

      3) How does their opinion of my
         juice compare to their opinion
        for competitor juices?

      4) Will people buy my juice?
Consumer tests – general rules

PEOPLE:
Who ? :      TARGET MARKET CONSUMERS

How many ? : THE MORE THE BETTER – AT LEAST 100

Everything we said on slide 15 about people applies.

ENVIRONMENT:
          SPECIFIC VENUE WITH INVITES or SHOWS/FESTIVALS/MARKETS
Where?:
          Context will affect the result you get.
SAMPLES & PRESENTATION:
Safe, representative, consistent, 3 digit random codes, balanced presentation
orders…
Branding ?/ Not?
Consumer Testing - PRACTICAL

Shall I do a preference test against Innocent’s ?

  Ø What would that show us?

  Whether the consumers prefer mine more than Innocent’s.

  Ø What wouldn’t it show us?

  Whether they like my juice at all. Preferable = not necessarily likeable.

  How much they do or don’t like my juice in its own right.

  How big the difference is between their liking for mine and Innocent’s.

  If they’ll buy it. Whether the sweetness level is perfect; only if preferable/not.
Consumer Testing – PRACTICAL – ACCEPTANCE TEST

Each sample 1 by 1 + 9 point category scale:

“Please taste the sample & indicate your opinion by ticking a box below”

    ACCEPTANCE TEST will allow me to:

     See if & how much they like:
                      a) my juice.
                      b) Innocent juice.               …..in their own right /against expectations.

    Ask some more questions to understand key attributes important to product.
Consumer Testing – PRACTICAL – ACCEPTANCE TEST

Sample ingredient list:

Apples, ascorbic acid (vitamin C).

Does not contain:
• any of the official allergens as listed in 1169/2011
• alcohol

Vegan and vegetarian-friendly.
Consumer Testing – PRACTICAL – ACCEPTANCE TEST

Diagnosis questions:

2) Comment: “Please explain why you scored it as you did?”

    (I have not yet influenced them).

3) Just About Right scale: Sweetness (specific attribute)

“Please indicate by circling below, your opinion on the sweetness of the juice?”

(I have now influenced them, but I captured their unbiased thoughts first! So OK to ask this at this
point).
Consumer Testing - PRACTICAL– ACCEPTANCE TEST

 1) Do consumers like the taste of my new juice? Why ? and by how much?

 2) Is it sweet enough for them ? (I could store the fruit, press later; make it sweeter)

 3) How does their opinion of my
    juice compare to their opinion
   for competitor juices?

 4) Will people buy my juice?

How to improve design?
Consumer Testing -– ACCEPTANCE TEST - Results

Basic analysis results:

1) FREQUENCY of responses to each LIKING or JAR CATEGORY added up.

2) CALCULATE MODAL CATEGORY most frequently selected category.

3) PLOT GRAPHS

4) LOOK AT TRENDS - generally liking / disliking

5) TALLY COMMENTS > SEE TRENDS > USE TO EXPLAIN TRENDS

More advanced analysis:

• Statistical testing for significant difference can be applied. Come back Sept!
Consumer Testing -– ACCEPTANCE TEST - Results
Consumer Testing - ACCEPTANCE TEST – Sum up

ACCEPTANCE TEST useful for:

1) Testing out NEW / NOVEL product on own or multiple recipes.

2) BENCHMARKING against competition.

3) Can add WHY? questions – discover KEY DRIVERS LIKING
                       ….. drivers you weren’t thinking about
 With packaging       Do they like the        Will they try it ?
                      packaging and
                      branding ? How
                      much?
                                                                     Wording & order
 With packaging &     Is everything meeting   Will they buy it?
 price & context      expectations?                                questions CRITICAL!
 Blind samples        Do they like its        Will they repeat
 No packaging         sensory properties?     purchase ?
                      How much?
Descriptive Tests

• Putting words to sensory sensations, so you can
  communicate about the product to others:

             1) CHARACTERISE the product in detail

             2) DEFINABLE

             3) RELEVANT to those using the data

• Describes the facts ; no opinion.

• Sensory description important for: 1) specifications
                                     2) quality attribute sheets

                                      Often useful for marketing
Descriptive analysis – A qualitative profiling method for SMEs

PEOPLE:

Who ? :   Ø Familiar / experienced with product.
          Ø Interested / willing.
          Ø People already good at verbalising sensations
                                                  Pre-screening questionnaire
          Ø Writing marketing material – consumers > consumer language.
          Ø Writing a specification – employees > language familiar to those in QA.

How many ? : 6 - 8

Everything we said on slide 15 about people, sample presentation, consistency
applies.
Descriptive analysis – A qualitative profiling method for SMEs

Scenario: Qualitative descriptive profiling – Crisps

A crisp manufacturer wants to characterise their new crisp product in order to
create a sensory description for a specification and quality attribute sheet.

 Ingredient list/ special dietary info:

 1st sample – Potatoes, sunflower oil, sea salt. Gluten free.
 These chips are suitable for vegans.

 2nd sample – Potato, high oleic sunflower oil (33%), salt.
Descriptive analysis – A qualitative profiling method for SMEs

1) GENERATE WORDS – ALONE – note down in grid provided.

2) DISCUSS as a group.

3) DEFINE the words.
            Ø Name reference benchmarks > training

4) REFINE TERMS – merge common descriptors.

5) KEEP A TALLY – no. of times a word is used by multiple people
                        Ø Common usage > key attribute
A Basic Sensory Specification
                                Basic Sensory Profile : X brand Ready Salted Crisps
                                   This qualitative profile represents brand standard quality.

Appearance:

Aroma:

Taste & flavour:

Mouthfeel/texture/trigeminal:

Aftertaste:
More Advanced Sensory Specification
                          Traffic Light Sensory Specification: X brand Ready Salted Crisps
               BRAND STANDARD QUALITY                ACCEPTABLE – for release              UNACCEPTABLE – reject
Appearance
             Insert                         Insert                                Insert

             photo                          photo                                 photo

Aroma

Taste &
flavour

Trigeminal
sensations

Mouthfeel/
Texture

Aftertaste
Descriptive analysis – A qualitative profiling method for SMEs

                                Your product.               Acceptance
   Descriptive                                               Test Data
     Profile                      Competing                 How much liked
Key sensory properties             products                     & why

                               POWERFUL STUFF!!
                         • Market awareness.
                         • Informed product development.
                               Ø properties to create
                               Ø properties to avoid
In Summary

• You can get a lot of info. from some very simple tests, on a low budget.

• Have a clear objective and a good plan.

• Do everything possible to reduce bias in:
                          Ø Samples
                          Ø Way test is conducted
• Use the most appropriate people for each test & use as many as possible -
  remember about individual differences in sensory acuity & perception.

• Give the people best possible environment to make good measurements for you.

• Practice required to aid descriptive ability – you & employees.

• Sensory evaluation has benefits operationally & commercially.
Other Sensory Workshops

For more detail:

19th September 2018

Sensory Evaluation Course

• Accredited by Institute of
  Food Science and Technology.

• Exam to get an IFST certificate.

Please take a flyer ….
Further Work

For more information on sensory evaluation
                      or
          bespoke sensory work
               free to SMEs in
      Nottinghamshire & Derbyshire
                   contact:
    Alice Jones – Sensory Scientist
         University of Nottingham
              0115 951 6739
      alice.jones@nottingham.ac.uk
    www.foodinnovationcentre.co.uk
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