1、Designation: E 1395 90 (Reapproved 2004)Standard Test Method forSensory Evaluation of Low Heat Chilies1This standard is issued under the fixed designation E 1395; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A 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 This test method describes standardized procedures forthe sensory evaluation of heat in low heat chili peppers rangingfrom 20
3、0 to 2500 Scoville heat units.1.2 This test method is intended as an alternative to theScoville heat test (see ASTA Method 21.0 and ISO 3513), butresults can be expressed in Scoville heat units (S.H.U.).1.3 This test method does not apply for ground red pepperor oleoresin capsicums.1.4 The values st
4、ated in SI units are to be regarded as thestandard.1.5 This standard does not purport to address all 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
5、regulatory limitations prior to use. Specific precau-tionary statements are given in Section 8.2. Referenced Documents2.1 ASTM Standards:E 1083 Test Method for Sensory Evaluation of Red PepperHeat22.2 ASTA Standard:ASTA Method 21.0 Official Analytical Methods32.3 ISO Standard:ISO 3513-1977 (E), Spic
6、es and CondimentsChiliesDetermination of Scoville Index43. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 approaching strong heatN-vanillyl-n-nonamide,1.30 ppm. This is 13.0 cm on the 15-cm line scale. It is unusualto see a ground red pepper stronger than this. But in the eventt
7、hat a pepper with more than expected heat is tested, thereremains the last 2 cm on the 15-cm line scale.3.1.2 low heat chiliesvariety of red pepper (capsicum)containing less than 0.1 % capsaicin (less than 2500 Scovilleheat units).3.1.3 moderate heatN-vanillyl-n-nonamide, 0.80 ppm.This is a“ moderat
8、e” amount of pepper heat. It reads 10 cm onthe 15-cm line scale.3.1.4 rinseto purge the oral cavity with unsalted sodacrackers and 20C spring or distilled water by slowly chewingand swallowing the cracker, followed by swirling the wateraround in the mouth and swallowing. This procedure isrepeated as
9、 often as is natural and comfortable for the panelist.3.1.5 Scoville heat units (S.H.U.)the commonly acceptedunit for expressing heat levels in capsicum products (see ISO3513 and Footnote 4). S.H.U. range from 0 to 1 500 000.3.1.6 slight heatN-vanillyl-n-nonamide, 0.40 ppm. This isa “slight” amount
10、of pepper heat. It reads 5 cm on the 15-cmline scale.3.1.7 strong heatbest defined by concept. Hotter than the1.30 ppm N-vanillyl-n-nonamide sample. It reads 15 cm on the15-cm line scale.3.1.8 threshold heatbest defined by concept rather than bya standard dilution of N-vanillyl-n-nonamide. Threshold
11、 is thatpoint where a panelist just barely senses burn and heat, or both.It reads 1.25 cm on the 15-cm line scale.3.1.9 zero heatN-vanillyl-n-nonamide, 0 ppm. No sensoryheat. It reads 0 cm on the line scale.4. Summary of Test Method4.1 Ground low heat chili peppers are steeped in hot waterwith polys
12、orbate-80 for 20 min, filtered, and the filtrate dilutedin room temperature water. Trained panelists compare the heatin the pepper extract to a known concentration of a standardsolution of synthetic capsaicin (N-vanillyl-n-nonamide) using a15-cm line scale. The testing procedure is timed and takes 2
13、min for one test sample and 9 min for two test samples.54.2 Panelists are screened for their accuracy and precisionand trained to use the 15-cm line scale during two to three15-min training sessions.1This test method is under the jurisdiction of ASTM Committee E18 on SensoryEvaluation of Materials a
14、nd Products and is the direct responsibility of Subcom-mittee E18.06 on Food and Beverage Evaluation.Current edition approved Oct. 1, 2004. Published October 2004. Originallyapproved in 1990. Last previous edition approved in 1997 as E 1395 90 (1997)e2.2For referenced ASTM standards, visit the ASTM
15、website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Spice Trade Association, Box 1267, EnglewoodCliffs, NJ 07632.4Available from Americ
16、an National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.5Gillette, M. H., Appel, C. E., and Lego, M., “A New Method for the SensoryEvaluation of Red Pepper Heat,” Journal of Food and Science, Vol 49, No. 4, 1984,p. 1028.1Copyright ASTM International, 100 Barr Harbor Driv
17、e, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.3 Standard general requirements for sensory testing arefollowed (see Test Method E 1083).5. Significance and Use5.1 This test method provides quick and accurate ratings forthe sensory heat in low heat chilies ranging from 200 to 2500S
18、coville heat units.5.2 Sensory results from this test method correlate highly(r2= 0.94) with results from high-pressure liquid chromatog-raphy; making the two methods substitutable.66. Apparatus6.1 Magnetic Hot Plate Stirrers, two.6.2 Beakers, 600-mL, four.6.3 Small Beaker, 50 to 100 mL.6.4 Analytic
19、al Balance, capacity greater than 300 g, sensi-tive to 0.01 g.6.5 Volumetric Flasks, 1000-mL, stoppered.6.6 Stopwatch.7. Reagents and Materials7.1 Coffee Filter Papers, or low flavor qualitative filterpaper.7.2 Medicine Cups.7.3 Unsalted Soda Crackers, unsalted tops.7.4 Water, bottled, distilled, or
20、 deionized when available, orstill spring water.7.5 Polysorbate-80, food grade.7.6 Rating Forms, 15-cm line scale anchored at 0 (none),1.25 cm (threshold), 5 cm (slight), 10 cm (moderate), 15 cm(strong); see Appendix X1.7.7 N-vanillyl-n-nonamide, available from Penta Interna-tional.8. Precautions8.1
21、 Pure N-vanillyl-n-nonamide will burn the eyes and skinupon direct contact. Gloves and caution must be used whenhandling N-vanillyl-n-nonamide in the crystalline form.9. Calibration and Standardization of Panelists9.1 Select ten to twelve panelists based on availability,attitude, and motivation of p
22、anelists. Screening for tastesensitivity is not necessary.9.2 Prepare stock solution of N-vanillyl-n-nonamide (see10.1.2).9.3 Dilute the stock solution of N-vanillyl-n-nonamide tothe following concentrations:9.3.1 N-vanillyl-n-nonamide, 0 ppmAdd none of thestock solution to 200 mL of water.9.3.2 N-v
23、anillyl-n-nonamide, 0.40 ppmDilute 13.4 g ofstock solution to 200 mL with water.9.3.3 N-vanillyl-n-nonamide, 0.80 ppmDilute 26.8 g ofthe stock solution to 200 mL with water.9.3.4 N-vanillyl-n-nonamide, 1.30 ppmDilute 43.3 g ofthe stock solution to 200 mL with water.9.4 Session 1 (15 min)Brief the pa
24、nelists on the purposeof this test method. The purpose of the first session is tostandardize their tongues and mouths to the reference standardswith respect to the 15-cm line scale on the ballot (Fig. 1).Explain to the panelists that they may use any of the infinitenumber of points on the line scale
25、 to describe how hot a givensample is. Panelists will taste (see 10.2.3.1-10.2.3.3) theprepared coded standard dilutions, evaluate them critically,concentrating and memorizing their individual sensory heatlevels. Panelists rinse well between samples with unsalted sodacrackers and spring or distilled
26、 water for 2 min (they aretimed). After the standards have been tasted, the correct ratingfor each reference standard is given. A new set of labeledstandard dilutions is presented to the panelists to review.Definitions for “0,” “ threshold,” “slight,” “moderate,” “ap-proaching strong,” and “strong”
27、are provided. Refer to 3.1.4-3.1.8.9.5 Session 2 (15 min)This session should follow the firsttraining session by one to two days. During this session, thepanelists will be both trained and tested. Explain to thepanelists how they will be evaluating the actual red pepper testsamples. Explain the enti
28、re tasting procedure as defined below:9.5.1 Panelists are served 10-mL portions of each of twosamples in coded medicine cups. The control (0.4 ppmN-vanillyl-n-nonamide) is always served first, coded “C.” Thetest sample is served second, with a random two-letter code.Two sets of samples are evaluated
29、 per sitting. The tastingprocedure is described in 10.2.3.9.5.2 For this second training session, the panelists areserved the “control” first, coded “C,” then a test sample codedwith a random two letter code. They will evaluate two sets ofsamples:9.5.2.1 Control and 0.80 ppm N-vanillyl-n-nonamide.9.
30、5.2.2 Control and 0.40 ppm N-vanillyl-n-nonamide (thesame as the control).9.5.2.3 Do not tell the panelists what the test samples are.After learning the standard heat intensities during Session 1,they theoretically should rate the 0.80-ppm sample at “moder-ate” and the 0.40-ppm sample at “slight” on
31、 the line scale.6Hoffman, P. G., Salb, M. C., and Galetto, W. G., “Separation and Quantitationof Red Pepper Heat Principles by Reverse Phase HPLC,” Journal of Agriculturaland Food Chemistry, Vol 31, No. 6, October 1983, p. 1326. FIG. 1 Low Heat Chilies Sensory versus HPLCE 1395 90 (2004)2A2-cm varia
32、tion from the desired response is acceptable. Thepanel, as a whole, should also be within 2 cm of the desiredresponse. If not, another training session must be conducted.After the session, advise the panelists about the sampleidentities and the expected ratings for them. Panelists mustreproduce thei
33、r judgment within 2 cm of the desired response.A minimum of five panelists should pass for the formal testing.Repeat the training procedure until this is achieved (approxi-mately three training sessions).9.5.2.4 End the training session by giving the panelists asample of low heat chilies to acquaint
34、 panelists with the flavorof chilie peppers (not present in the standards).10. Procedure10.1 Sample Preparation:10.1.1 Itemize sample preparation procedures in a quickreference chart (see Appendix X1).10.1.2 Evaluate two samples per test: (1) a known control(0.40-ppm dilution of N-vanillyl-n-nonamid
35、e) prepared fromthe stock solution; and (2) the unknown low heat chili peppers.Preparation of the two samples is as follows:10.1.3 Prepare the “stock” solution of N-vanillyln-nonamide (6.0 ppm N-vanillyl-n-nonamide and 200 ppmpolysorbate-80) by diluting N-vanillyl-n-nonamide andpolysorbate-80 in spr
36、ing or distilled water. Keep this solutionstoppered and refrigerated for the duration of the test series. Itwill remain stable for two or three weeks. Check regularly forprecipitation of N-vanillyl-n-nonamide. To make the stocksolution, weigh 0.60 g N-vanillyl-n-nonamide and 20 g ofpolysorbate-80 in
37、to a small beaker (50 mL). Heat the mixtureon a hot plate (low setting) for a minimum of 10 min todissolve N-vanillyl-n-nonamide. Quantitatively transfer theheated mixture into a 1-L volumetric flask using hot (about70C) spring or distilled water. Cool to room temperature.Dilute the transferred solu
38、tion to 1 L using room temperature(20C) spring or distilled water. Dilute 10 g of this solution to1 L in a second 1-L volumetric flask. Stopper and refrigerate.Final concentrations equal 6 ppm N-vanillyl-n-nonamide, 200ppm polysorbate-80. This is the “stock solution.”10.1.4 For each test, dilute the
39、 stock solution of N-vanillyl-n-nonamide to 0.40 ppm N-vanillyl-n-nonamide and 13.3 ppmpolysorbate-80 in 20C spring or distilled water by diluting13.4 g of the stock solution to 200 mL with room temperaturewater. This diluted solution is referred to as the “control” foreach test.10.1.5 Low Heat Chil
40、i Pepper SamplesOn the day of thetest, combine 4.0 g of the low heat chili pepper sample and0.04 g of polysorbate-80 in a 600-mL beaker and dilute to 200mL with 70C spring or distilled water and place on thepreheated (4 min on high) hot plate stirrer on medium stirspeed. Set the hot plate stirrer on
41、 high heat for 1.5 min then onmedium heat for 20 min of simmering (90C) and stirring.Filter the extracted pepper using coffee or qualitative filterpapers. Dilute 100 g of the filtrate with 100 g of 20C spring ordistilled water. Final concentration of the extracted and dilutedsolution is 10 000 ppm c
42、hili pepper and 100 ppm polysorbate-80.10.2 Sample Presentation:10.2.1 A round or conference table is preferred, but boothsmay be used as long as all panelists are able to be “monitored”by the panel leader. Conduct the test with all five to ten trainedpanelists simultaneously as the process is timed
43、 by the panelleader (if a panelist misses a panel, he or she must also betimed during his or her “make-up” test). Red lights arerecommended to mask color differences.10.2.2 Serve panelists 10-mL portions of each sample incoded medicine cups. Serving temperature should be at roomtemperature and equal
44、 for all samples. The control is alwaysserved first, coded “C.” The test sample is served second, witha random two-digit code. Evaluate two sets of samples (controland test sample) per sitting. Use a 15-cm line scale anchored at0 cm (0 heat), 1.25 cm (threshold heat), 5.0 cm (slight heat),10.0 cm (m
45、oderate heat), and 15 cm (strong heat) is used. Aseparate scale is used for each set of samples. Order of thepresentation of the sample sets should be balanced to avoidposition bias.10.2.3 The tasting procedure is as follows:10.2.3.1 Rinse before the first sample (control) with un-salted soda cracke
46、r and 20C spring or distilled water, or both.Allow 15 s between rinsing and sampling.10.2.3.2 Evaluating left to right, take the entire first sample(control) in mouth, hold for about 5 s, swallow slowly.10.2.3.3 Wait 30 s (timed) from initial intake keeping mouthclosed.10.2.3.4 Rate the first sample
47、 as “slight” on ballot.10.2.3.5 Alternately rinse with 20C spring or distilledwater and chew on an unsalted soda cracker during a 60-sinterval (timed).10.2.3.6 Rinse with 20C spring water (immediately) priorto the second sample. Allow 15 s between rinsing andsampling.10.2.3.7 Take the entire second
48、sample (test sample) inmouth, hold for about 5, swallow slowly.10.2.3.8 Wait 30 s (timed), keeping mouth closed.10.2.3.9 Rate second sample.10.2.3.10 Panel dismissed if only one test sample is to beevaluated.10.2.3.11 If two test samples are being evaluated, wait 5.0min (timed). Rinse well with spri
49、ng or distilled water andunsalted crackers during this time.10.2.3.12 Repeat 10.2.3.1-10.2.3.9 for the second set ofsamples.10.2.4 Note that the control is rated before each test sample.11. Interpretation of Results11.1 Sensory heat ratings are obtained by measuring thedistance (in centimetres to the first decimal place) from the lefthand side of the scale (0) to the mark placed on the ballot foreach sample. Values range from 0.0 to 15.0, as the scale is 15cm long.11.2 Individual panelist ratings are averaged to generate apanel mean.11.3 Sensory heat ratin
