1、Designation: E 1490 03Standard Practice forDescriptive Skinfeel Analysis of Creams and Lotions1This standard is issued under the fixed designation E 1490; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A
2、 number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 The objective of this practice is to provide proceduresthat may be used in the design and analysis of studies of skincare products th
3、at compare qualitatively and quantitativelyvarious sensory attributes and their intensity (or strength) overtime. These properties can then be used to define the perfor-mance of skin care products to provide direction in productformulation, research guidance, and claim substantiation.1.2 Guidelines
4、are provided for the definition of eachproduct attribute or term, range of the rating scales, proceduresfor the manipulation of product alone and on the skin, selectionand training of panelists, handling of products, and skinconditioning prior to tests.1.3 This standard does not purport to address a
5、ll of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:E 253 Terminology Re
6、lating to Sensory Evaluation of Ma-terials and Products23. Terminology3.1 DefinitionsDefinitions of descriptive terms other thanthose given as follows appear in the procedure of AppendixX1.3.1.1 afterfeelthe feel of the skin after application of thesample, with or without touching, usually measured
7、at a settime interval.3.1.2 deliverythe stage during which the product is dis-charged onto the finger(s) or skin.3.1.3 greasya somewhat thick, sticky, either slightly re-sistant or slightly slippery film (for example, petrolatum).3.1.4 oilya thin, slippery, non-sticky film (for example,mineral oil).
8、3.1.5 panel leadera person who is responsible for con-ducting descriptive panels and control product, protocols, andpanel maintenance.3.1.6 pick-upthe stage during which the product is ma-nipulated between the fingers.3.1.7 reference anchorsproducts that are used to demon-strate high or low intensit
9、ies of a particular attribute.3.1.8 rub-outthe stage during which the product is rubbedonto the skin.3.1.9 waxya rigid, dry, somewhat resistant residue.4. Summary of Practice4.1 This practice provides for the identification of panelistsselected and trained appropriately to evaluate the intensity and
10、duration of defined sensory characteristics of skin care prod-ucts. The details of specified procedures are defined in Sections7 and 8 of this practice.5. Significance and Use5.1 The procedure recommended in this practice can beused to assess the sensory appearance and tactile properties oflotions a
11、nd creams or ointment.5.2 This practice is applicable to product categories thatinclude skin lotions and creams; facial moisturizers; handlotions and creams; and skin care products for which theappearance and tactile properties need to be assessed.5.3 Procedures of the type described herein may be u
12、sed tocommunicate perceived sensory properties (appearance andfeel) between manufacturers and to the consumer through themedia. These guidelines are suggested to meet the need forascertaining the performance of experimental or commercialsamples.5.4 These procedures are to be used by persons who have
13、familiarized themselves with the procedures and have hadprevious experience with sensory evaluation.5.5 This practice provides suggested procedures and is notmeant to exclude alternate procedures that may be effective inproviding sensory evaluation descriptions.6. Equipment6.1 The following equipmen
14、t may be used during theevaluation process.1This practice is under the jurisdiction of ASTM Committee E18 on SensoryEvaluation of Materials and Products and is the direct responsibility of Subcom-mittee E 18.07 on Personal Care and Household Evaluation.Current edition approved Feb. 10, 2003. Publish
15、ed February 2003. Originallyapproved in 1992. Last previous edition approved in 1997 as E 1490 92 (1997).2Annual Book of ASTM Standards, Vol. 15.07.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.1.1 Template, used to outline the 2
16、-in. (51-mm) diametercircles on the forearm. It assures that consistent, measuredareas are delineated for product application and evaluation (forexample, a flexible plastic material with 2-in. (51-mm) diam-eter circles cut out for outlining with an appropriate marker).6.1.2 Light Source/Viewing Cond
17、itionsA consistent lightsource for each panelist is recommended for use during theevaluation of shine. The type of light source will depend on thespecific nature of the product being evaluated. It is importantthat all panelists receive the same amount of light on the armsand the same angle of light,
18、 and that the distance from the testsite and light be the same for each panelist (for example,high-intensity desk lamps).6.1.3 Skin Thermometer.36.1.4 Repeater Pipette.6.1.5 Metronome.6.1.6 Stopwatch.6.1.7 Syringe.6.1.8 Petri Dishes.6.1.9 Weight Boats.6.1.10 Hygrometer.7. Panel Selection and Trainin
19、g7.1 ObjectiveTo select and train a panel of 10 to 15 judgesto evaluate the skinfeel properties (included in appearance,pick-up, rub-out, and afterfeel stages) of lotions and creamsusing a descriptive analysis method that quantifies severalsensory attributes over time.7.2 Panel Section:7.2.1 Panelis
20、ts are recruited from within a company or thelocal community. The choice to use employees allows acompany to have the panelists on site and to keep proprietarysamples and information on site. The use of local communityresidents allows a company to schedule more panel time perweek and provides a smal
21、ler risk to losing panelists both on adaily basis and long term.7.2.2 A large group of candidates are recruited from thelocal community (50 to 75) by contacting community groups orplacing newspaper ads, or both. Candidates from within thecompany are contacted by interoffice memo or notices postedon
22、bulletin boards. Prior to the prescreening questionnaire,candidates should be informed of the time commitment fortraining (orientation and practice sessions), the potential dura-tion of the panel, the use of the panel, and the expectation ofeach panelist in terms of commitment to the panel. Thepresc
23、reening questionnaire is recommended for determiningavailability, interest, general knowledge of tactile properties,ability to use descriptive words, and ability to use rating scales(see Figs. 1-3).7.2.3 The 20 to 30 candidates who score best on theprescreening questionnaire (see 7.2.5 for criteria)
24、 participate inthe acuity screening phase (see Figs. 4 and 5). Candidates areasked to rate the intensity of skinfeel attributes for threesamples chosen specifically to represent the range for theattributes tested. One attribute is chosen from each evaluationcategory: appearance (for example, integri
25、ty of shape), pick-up(for example, firmness or stickiness), rub-out (for example,3Two telethermometers that would satisfy the guidelines identified in thispractice are Telethermometer Model 44TA, marketed by YSI (Yellow SpringsInstrument Company, Inc.), Yellow Springs, OH, or Digital Thermometer Mod
26、elNo. 5650 from Markson Science, Inc., Del Mar, CA.FIG. 1 Screening QuestionnaireFIG. 2 Touch QuizE1490032ease to spread or whitening), and afterfeel (for example,greasiness or amount of residue). For rub-out and afterfeelattributes, the three test products are applied in premeasuredamounts to three
27、 2-in. (51-mm) circles on each arm. Use onearm for the rub-out evaluation and the other arm for theafterfeel attribute.7.2.3.1 Candidates should have at least two products (of thethree tested) rated properly for three of the four attributes inorder to qualify as having sensory acuity.7.2.4 Each cand
28、idate is interviewed by the panel adminis-trator or trainer to determine attitude, interest, ability to learnand work in a group dynamics situation, and availability fororientation, practice, and panel sessions on a routine basis (seeFig. 6).FIG. 3 Scaling ExerciseFIG. 4 Rating ExerciseFIG. 5 Descri
29、ptive ExerciseE14900337.2.5 Select 10 to 15 panelists on the basis of the followingcriteria (see Figs. 7-12):7.2.5.1 Availability for the complete orientation and 80 to100 % of the practice sessions during training;7.2.5.2 No health-related problems: skin irritations, centralnervous system disorders
30、, or medications that interfere with thecentral nervous system and could reduce skin and musclesensitivity, and no previous history of allergy to lotions,creams, soaps, or other topical products;7.2.5.3 Correct and comprehensive descriptive answers to75 % or more of the open-ended tactile questions
31、in theprescreening questionnaire;7.2.5.4 Correct ratings of 80 % or more of the scalingexercise in the prescreening questionnaire;7.2.5.5 Correct ratings for two samples (of the three perattribute) for three of the four attribute scales; and7.2.5.6 Demonstration of good verbal skills, a high interes
32、tin descriptive and group dynamics tasks, and a cooperative yetconfident personality demonstrated in the interview.7.3 Panel Orientation:7.3.1 To begin training of the 10 to 15 selected panelists, thepanel trainer must orient panelists first to the general concepts,such as the definition, components
33、, and applications of descrip-tive analysis testing. This takes 1 to 2 h.7.3.2 Panelists are introduced to the need for strictly con-trolled procedures for the manipulation and application ofsamples and for the careful definition of each sensory attribute.This takes 1 to 2 h. (See Appendix X1 for pr
34、ocedures.)7.3.3 Discussion and demonstration of each skinfeel at-tribute are conducted for each stage: appearance, pick-up,rub-out, and afterfeel. This establishes the overall structure ofthe descriptive analysis of skinfeel properties. Panelists areencouraged to discuss each term, its definition, t
35、he protocol forevaluation, and the corresponding rating scale after they aredemonstrated by the panel trainer. This takes 2 h (see AppendixX1).FIG. 6 Interview QuestionnaireFIG. 7 Key for Screening Questionnaire (Fig. 1)FIG. 8 Key for Touch Quiz (Fig. 2)E14900347.3.4 For each skinfeel attribute, the
36、 procedure, definition,and scale are discussed and demonstrated using three to fivereferences (if possible) that represent the full intensity rangefrom none or extremely low to very high. This exercise takes4 to 5 h. (See Appendix X1 for high and low references foreach attribute.)7.4 Panel Practice:
37、7.4.1 Several practice sessions totaling 20 to 24 h are held toreview the orientation material. These include the following:7.4.1.1 Review of the procedure, definition, and rating scalefor each attribute (approximately 10 to 12 h); and7.4.1.2 Evaluation of one or two products; these are evalu-ated i
38、ndependently with the scale references, as needed (ap-proximately 10 to 12 h).7.4.2 Five to six pairs of samples (the samples in the pairshould initially be quite different from each other) are evalu-ated on all attributes for all four stages: appearance, pick-up,rub-out, and afterfeel during the pr
39、actice sessions (approxi-mately 10 to 12 h).7.5 ValidationAny one of the following methods can beused for panel validation.7.5.1 Choose three different products from the same productcategory (lotions, creams, gels, mousses, etc.) that demonstratesignificant differences on several attributes, as show
40、n by anestablished panel. The panel results from the recently trainedpanel are compared to the results of the same samples from theestablished panel. The recently trained panel should providesimilar results in 80 % of all attributes. This assumes 10panelists in each panel.7.5.2 Choose three differen
41、t products from the same productcategory (lotions, creams, gels, mousses, etc.) that demonstratesignificant differences on several attributes. The product evalu-ations of recently trained panels are compared to the resultsFIG. 9 Key for Rating Exercise (Fig. 4)FIG. 10 Key for Descriptive Exercise (F
42、ig. 5)FIG. 11 Key for Interview Questionnaire (Fig. 6)E1490035made by instruments that simulate the way products are appliedto the skin. The results of the panelists are validated by thecorrelation of the two sets of results (panel and instrumental).NOTE 1A lack of correlation may be a function of a
43、 poor choice ofinstrumentation measurement to simulate sensory product application ormanipulation, or both.7.5.3 Choose panel data across three different products fromthe results of the recently trained panel. Compare these datawith consumer attribute data for those attributes for whichconsumers hav
44、e demonstrated understanding and an ability todifferentiate among products. If the panel data correlates wellwith the previously validated consumer responses for similarattributes, the panel data can be considered valid.NOTE 2A lack of correlation may be a function of consumer termsthat are not rela
45、ted to the panel attributes or that are not understood by theconsumers.7.6 Panel MonitoringThree different factors can be moni-tored when reviewing data from the panel and panelists.7.6.1 A measure of the variability within the panel (that is,among panel members) can be determined with three replica
46、-tions of three samples for all attributes and all panelists. Themean value and standard deviation for each sample for eachattribute is computed. The panelists and panel leader can thenlook at the mean value for each sample and attribute versuseach panelists score. This permits the panel leader to s
47、eewhether one or more panelists are rating consistently higher orlower than the panel as a whole on one or more attributes.Review of the standard deviations across attributes demon-strates whether some panelists have standard deviations thatare more variable than most panelists and on which attribut
48、es.Large panel standard deviations indicate the need for a reviewof definitions, evaluation procedures, or reference standards forthe attribute in question.7.6.2 A measure of the repeatability of the panel as a wholecan be monitored by analyzing three replications of the panelsevaluation of two or t
49、hree samples of the same product type.An analysis of variance will determine whether the panelscores are the same for the same sample across the replicates.This analysis should be conducted for each attribute.7.6.3 Analysis of the data collected from three replicates oftwo or three different samples (as used in 7.6.2) can provideinformation on judge-by-treatment interactions in the analysisof variance. A significant F value on any attribute indicates thatone or more panelists are evaluating samples differently. Datafor these attributes should be plotted to determine