Sensory Evaluation for Cosmetics

Sensory Evaluation for CosmeticsFor “Wisdom & Research of Thai HerbalCosmeceuticals Application” by NanotecInstitue on Dec 17‐18, 2009Nonglak SatitkarnProcter & Gamble ThailandDecember 2009P&G beauty & gromming 1

Global R&D Organization• Over 8,000 Researchers, Scientists &Engineers• More than 1,100 PhDs• 80 Countries of Origin• 10,000 Active Patents• Over 500 beauty care clinical studies in thelast 5 yearsP&G beauty & gromming 3

P&G Beauty R&DAsiaEuropeKobe, JapanBeijing, ChinaSingaporeBangalore, IndiaLondon, UKDarmstadt, GermanyReading, UKNorth AmericaSouth AmericaSharon Woods, Cincinnati, Ohio, USAMiami Valley, Cincinnati, Ohio, USAHunt Valley, Maryland, USASouth Boston, Mass, USALA Technical Centre, VenezuelaP&G beauty & gromming 4

P&G ProductsBillion‐Dollar BrandsHalf‐Billion‐Dollar BrandsP&G beauty & gromming 5

Sensory Evaluation for CosmeticsOverview• Sensory definition and mechanism• Performance Evaluation Spectrum• Why need sensory evaluation in cosmetics• Sensory method development• Type of sensory test• Scale used in sensory test• Data Analysis and Statistics• Summary, Q&AP&G beauty & gromming 6

Sensory Evaluation ‐Definition• A behavioral science, a scientific method designed tomeasure, analyze, and interpret responses to products ormaterials characteristics as perceived through the 5 sensesHearing Pitches, tone, Sightintensity (decibels)Color,BrightnessSmell Character – TasteFloral, fruityIntensity ‐Strong, LightSweet, Sour,Salty, Bitter,Touch.Temperature ‐ hot, coldPressurePainP&G beauty & gromming 7

- Sensory MechanismStimulus energy(light, sound, odor …)Sensory receptors(eyes, ears, nose, …)NeuralimpulsesBrain areas(visual, auditory,olfactory …)Behavioral responseP&G beauty & gromming 8

Performance Evaluation SpectrumGivesTechnicalGuidanceIs itthere?Is itnoticeable?Does itmatter?PredictsMarketSuccessInstrumental Assessment(Chemical/Physical)Expert Assessments(Sensory/Clinical)Acceptance Studies(Consumer)Technical MeasureConsumer StudyToday’s focus….• Both Technical measure and consumer study are needed.• Technical measure should be rooted in consumer relevanceP&G beauty & gromming 9

Why need sensory evaluation incosmeticsPackageAppearanceVisual• Cosmetics are emotionallyinvolvedPerfumeIngredients,appearance,textureSounds whenopening/closingNoseVisual+TouchHearing• Sensory characteristics canlink to consumerperceptions• Optimization of sensorycharacteristics leads toconsumer satisfactionP&G beauty & gromming 10

Sensory Method UsesTechnology development• Prototype screening vs. design targets• Predictive testing for consumer acceptance• Claims supportQuality Control• No noticeable differences with product changes• Stability (fresh vs. aged, expiration dating)• Quality investigations (manufactured product)P&G beauty & gromming 11

Sensory Method Development• FacilityThe physical requirement guidelines for sensoryevaluation laboratories are mentioned in ASTM #MNL.60• ProductsScope of products tested depends on the objective oftesting. Basically we have the broad range of productsavailable in the market.• PanelsQualified or trained panels are important for sensoryevaluation. Panels must pass the recruiting criteriabefore get training. Recruitment tests can bediscrimination test, rank order test or matching test.P&G beauty & gromming 12

Sensory Method DevelopmentPanel ‐> Human Senses• Physiological of Sense• Screen/Select panel from product user• NOT every consumer can detectthe product difference• Increase efficiency of sense requiredtraining & practice• Psychological of Sense• Environment influence, time,attitude, stimulus effect, mutualeffectP&G beauty & gromming 13

Sensory Method Development• Experimental Design• Match objective, controlcondition/variables, testingarea• Panel Instrument• Human has variations,difference, biasP&G beauty & gromming 14

Sensory Evaluation for Cosmetics4 Steps of Method DevelopmentDEFINE OBJECTIVEProject Scope &Purpose of the testVALIDATE/ USEAccurate? Precise?Repeatability?Correlation? Predictable?GET STARTED- Determine the type of test.- Sample preparation- Questionnaire preparationand attribute selectionASSESS-Analyse data by statistics- Does it seem to work ? Ifso, go on to ValidateIf not, fine-tune methodP&G beauty & gromming 15

Lotion ProjectDefine Objectives & Getting StartedExpected outcome:Objective: A more•Measure absorption to skin with sensory panel•Does lotion spread easily when you apply on skin?•Any attributes besides spreadability affect absorption?Eg. Residue on skin, viscosity of product?• Easy to spread and easy absorption to skin.P&G beauty & gromming 16

Lotion ProjectDefine Objectives & Getting StartedExpected outcome:Spread/Absorb•Objective: distinguish new formula vs. current formula•Measurement: sensory panel via appearance, force and feelafter apply.Does not have residue left after you apply on skin•Objective: disaster check ?•Measurement: appearance via image analysis, fast or slowP&G beauty & gromming 17

Sensory Evaluation for CosmeticsAssess• Check‐step: Are you on the right track ?• Are you getting the expected result (right rank‐order)• Can the method distinguish products you know to bedifferent?• Can you reproduce your results ?• Do the results of measurements on control productsmake sense?• If so, go to full validation.• If not, further optimize the method before validation.P&G beauty & gromming 18

Sensory Evaluation for CosmeticsValidateRepeatability is the ability of an operator/equipment toobtain consistent results when the same experiment isreplicated at identical conditions.Precision is the inherent variability of the process.Reproducibility of a method is defined as the consistencyof results across operators/equipment/time.P&G beauty & gromming 19

Sensory Evaluation for CosmeticsValidateTop‐class R&D methods build toward 3 criteria:Predictive(Defendable, Scaleable)ReliableRelevantP&G beauty & gromming 20

Sensory Evaluation for CosmeticsValidate• Relevant‣ Method Suitability‣ Relevancy of Equipment, Materials, Environment, Product Samples• Reliable‣ Accurate and Precise‣ Robustness• Repeatable• Reproducible‣ Sensitive• Predictive, Defendable and Scaleable‣ Internally/Externally sound; can be used for advertising claims‣ Scaleable and Consumer ObservableP&G beauty & gromming 21

Method Validation‐ Relevancy Of Test MethodStep 1. Is the method relevant?• Mimic the consumer habits,• Are the lab samples consumer relevant?• Environmental conditions representative of consumer’sin‐home conditions?Step 2: Is your method accurate & precise?• Is the method measuring what you intended?• Do you have reasonable standard deviations?• Compute relative standard deviation as% RSD = (Standard Deviation) * 100 / (Average)P&G beauty & gromming 22

Method Validation‐ Reliability Of Test MethodStep 3: Is your method robust?• Can the same person repeat the same results?• Can different persons reproduce the same results?• If the experiment is conducted on a different days, can the sameresults be repeated?• Can you generate robust results across different conditions?P&G beauty & gromming 23

Method CorrelationFinding Associations• Correlation coefficient r is always between –1 and +1• A correlation close to 0 means no linear relation• A correlation close to 1 or –1 (< ‐0.75 or > 0.75) suggests a strongassociation between the two data sets• Correlations in the range (0.5 to 0.75) and (‐0.75 to ‐0.5) are moderate• Correlations between ‐0.5 and 0.5 are weak• R 2 is squared correlation; a measure of ‘goodness of fit’P&G beauty & gromming 24

Method CorrelationFinding Associations• Always make a ‘scatter plot’ for correlations!• A strong correlation can be the result of one extreme or ‘influential’ point• A seemingly poor correlation can also be caused by several outliers900 R 2 = 0.98, r = 0.9980070060050040030020010000 1 2 3 4 5 6 7 8 9without oultier: R 2 = 0.034, r= 0.1860050040030020010000 1 2 3 4R 2 = 0.011, r = 0.108007507006506005505004504003503000 1 2 3 4 5 6 7 8 9 10800 without extremes R 2 = 0.84, r = 0.917006005004003000 1 2 3 4 5 6P&G beauty & gromming 25

Types Of Sensory/Consumer Evaluation1. Difference/discrimination testing• Threshold• Is something there? Is it noticeable?• Degree of Difference• How big is the difference?2. Descriptive analysis• Intensity of many sensory characteristics• How much of this characteristic is present ?3. Affective testing (Preference/Acceptance) ‐> ConsumerStudy!• Like/dislike ‐> use hedonic scale rather than intensity scale• How much do they like/dislike, perception?P&G beauty & gromming 26

Sensory Study vs. Consumer Study• Sensory testing isolates what is perceived or noticed inorder to understand it.• Sensory testing is done under controlled conditions withscreened & trained judges.• Sensory testing measures the relative intensity of asensory product characteristic (e.g. spreading, cooling,smoothness, sticky).• Sensory testing ignores preference & other signals, purelymeasure intensity.• Consumer tests involve expectations of product, previousexperience, signals from smell & color, etc.P&G beauty & gromming 27

Types Of Sensory Evaluation: 1. Difference• Pair test: compareA vs. B• Triangle test: chooseodd one out of A, A & B524479183• Duo-Trio test: compareA & B versus referenceControl621355P&G beauty & gromming 28

Types Of Sensory Methods: 2. Descriptive• Quantitative, objective description of productattributes.• Expert or Descriptive Analysis Panel requiresextensive training and regular calibration.What doyou noticeabout thisshampoo?ocreamy?olather?ofresh?o long last fragrance?oclean?oeasy to rinse?o Other?RatingNotSweetLess LatherVerySweetHigh Lather0 1 2 3 4 5 6 7 8 9 10P&G beauty & gromming 29

Types Of Sensory Methods: 3. Affective EvaluationOr Consumer StudyAcceptance/RejectionCannot be trained – consumersare accessorsLike/DislikeWhat make them like/dislikeOpinionAnalyze information, cost,time, place, specificationAttitudeInfluence by environment,society, culturePerceptions/ResponsesUse 5 sensesP&G beauty & gromming 30

Scale used in sensory test• Qualitative Scale• Groupinge.g. difference/no difference 1)open end question, voluntary comment 2)• Ranking e.g. color ranking test• Quantitative Scale• Category scaling e.g 5, 7, 9, 11 scale• Hedonic scale –degree of like/dislike 2)• Just about right scale, JAR 2)• Face scale/Smiley scale• Linear scale ‐> Intensity 2)1) Most used in difference testing2) Most used in descriptive testing & consumer studyP&G beauty & gromming 31

Scale used in sensory test‐exampleHedonic scale1 ไมชอบที่สุด/ไมชอบเลย2 ไมชอบมาก3 ไมชอบปานกลาง4 ไมชอบเล็กนอย5 เฉยๆ6 ชอบเล็กนอย7 ชอบปานกลาง8 ชอบมาก9 ชอบมากที่สุดJust about right scale1 ออนมากไป much too weak2 ออน Weak3 พอดี Just about right4 แรง strong5 แรงมากไป much too strongP&G beauty & gromming 32

Data Analysis and Statistics• Average (Mean)• Standard deviation, Relative standard deviation• Student T‐test• Analysis of Variance (ANOVA‐ one way & multiple ANOVA)• Consider significant @ 90 or 95% confidential level• Factor Analysis• Ancova analysis• Correlation & Regression Analysis• ModelingP&G beauty & gromming 33

Data Analysis and Statistics• Student T‐testGeneral recommendation for comparing 2 sets of data.• Analysis of Variance (ANOVA‐ one way & multipleANOVA)• Comparing data from 2 sets or more• Considering homogenous group of difference i.e.significant @ 90 or 95% confidential level• Mulitiple ANOVA are recommended when more than 1variables impact the resultsP&G beauty & gromming 34

Sensory Evaluation for CosmeticsSummary• Sensory is one of the useful tool to assess cosmeticperformance.• Recruit, training, refreshing panels are the importantkeys to get the best quality of panels. Keepmaintenance panels help to use sensory method lastlonger.• Clarify objective, getting start on the right attributes,access & validate for use, these steps lead to productperformance success via sensory evaluation.• Appropriate statistics and advance methodology helpsto analyze data usefully.P&G beauty & gromming 35

Acknowledgement & Reference1. Dr. Nicolette Vanderklaauw. Section Head Upstream & MethodsHair Care Product Development Procter & Gamble Kobe TechnicalCenter Japan in Predictive Method Modeling Training Course atKTC Procter & Gamble‐ August 2008.2. ปราณี อานเปรื่อง. หลักการวิเคราะหอาหารดวยประสาทสัมผัส. จุฬาลงกรณมหาวิทยาลัย 25513. Stone Herbert, Joel L Sidel. Sensory Evaluation Practices. AcademicPress 2004.4. ASTM stock #MNL.60 Physical requirement guidelines for sensoryevaluation laboratories.5. Antimano Elma. Senior Scientist. Product Development Olay SkinCare. Procter& Gamble Singapore technical center, Singapore.P&G beauty & gromming 36

Thank You !!P&G beauty & gromming 37