1、Designation: F1308 98 (Reapproved 2014)Standard Test Method forQuantitating Volatile Extractables in Microwave SusceptorsUsed for Food Products1This standard is issued under the fixed designation F1308; the number immediately following the designation indicates the year oforiginal adoption or, in th
2、e case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers complete microwave suscep-tors.1.2 This test method covers a p
3、rocedure for quantitatingvolatile compounds whose identity has been established andwhich are evolved when a microwave susceptor sample istested under simulated use conditions.1.3 This test method was collaboratively evaluated with avariety of volatile compounds (see statistical evaluation). Forcompo
4、unds other than those evaluated, the analyst shoulddetermine the sensitivity and reproducibility of the method bycarrying out appropriate spike and recovery studies. Theanalyst is referred to Practice E260 for guidance.1.4 For purposes of verifying the identity of or identifyingunknown volatile comp
5、ounds, the analyst is encouraged toincorporate techniques such as gas chromatography/massspectroscopy, gas chromatography/infrared spectroscopy, orother techniques in conjunction with this test method.1.5 A sensitivity level of approximately 0.025 g/in.2isachievable for the compounds studied in Tabl
6、e 1. Where othercompounds are being quantitated and uncertainty exists overmethod sensitivity, the analyst is referred to Practice E260 forprocedures on determining sensitivity of chromatographicmethods.1.6 The values stated in SI units are to be regarded asstandard. No other units of measurement ar
7、e included in thisstandard.1.7 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 regulatory limitations p
8、rior to use. Specific safetyhazards warnings are given in 10.2, 11.1, and 11.6.2. Referenced Documents2.1 ASTM Standards:2E260 Practice for Packed Column Gas ChromatographyF1317 Test Method for Calibration of Microwave Ovens2.2 TAPPI Standards:T 402 Standard conditioning and testing atmospheres forp
9、aper, board, pulp handsheets, and related products3TIS 808 Equilibrium relative humidities over saturated saltsolutions33. Terminology3.1 Definitions:3.1.1 microwave susceptorsa packaging material which,when placed in a microwave field, interacts with the field andprovides heating for the products t
10、he package contains.3.1.2 volatile extractablesthose chemical species whichare released from the microwave susceptor and can be detectedin the headspace under conditions simulating those underwhich the susceptor is used. Extractability does not necessarilymean migration of the extractable species to
11、 the product beingheated on the susceptors.4. Summary of Test Method4.1 Volatile extractables are determined by subjecting asample of the susceptor material to microwave heating, fol-lowed by headspace sampling and gas chromatography. Quali-tative analysis may be carried out on a gas chromatograph(G
12、C) coupled to an appropriate detector capable of compoundidentification. Volatile extractables are quantitated by compari-son with standards of known concentration.5. Significance and Use5.1 This test method is intended to measure volatile extract-ables that may be emitted from a microwave susceptor
13、 materialduring use. It may be a useful procedure to assist in minimizing1This test method is under the jurisdiction of ASTM Committee F02 on FlexibleBarrier Packaging and is the direct responsibility of Subcommittee F02.15 onChemical/Safety Properties.Current edition approved April 1, 2014. Publish
14、ed April 2014. Originallyapproved in 1990. Last previous edition approved in 2008 as F1308 98(2008).DOI: 10.1520/F1308-98R14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
15、refer to the standards Document Summary page onthe ASTM website.3Available from Technical Association of the Pulp and Paper Industry (TAPPI),15 Technology Parkway South, Norcross, GA 30092, http:/www.tappi.org.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19
16、428-2959. United States1the amount of volatile extractables either through susceptordesign or manufacturing processes.5.2 Modification of this procedure by utilizing appropriatequalitative GC detection such as a mass spectrometer in placeof the flame ionization detector may provide identification of
17、volatile extractables of unknown identity.6. Interferences6.1 Gas ChromatographyBecause of the potentially largenumber of chemical species that can be analyzed using thismethodology, not all species will be resolved from one anotheron a particular GC column under a given set of conditions.Techniques
18、 available to the analyst to verify the identity of thespecies being quantitated include retention time comparisonsusing alternate GC conditions or using an alternate GC columnto verify identification. Good judgement of chromatographicresults is always important.4,5,6Refer to Practice E260 forguidan
19、ce.6.2 ApparatusBecause this test method is designed fortrace volatiles, and is highly sensitive, contaminants on vials,septa, syringes, etc. can lead to misinterpretation of results.Preparing apparatus properly and carrying out blank determi-nations as specified in the procedure is essential to min
20、imizethis possibility.7. Apparatus and Reagents7.1 Microwave OvenCalibrated, 7006 35 W, no turntable.See Test Method F1317.7.2 Humidity Chambers, operated at 50 % RH and 23C.7.2.1 Requirements for constant temperature-humiditychambers and equilibrium relative humidities over saturatedsalt solutions
21、are outlined in TAPPI Methods T 402-om-88, andTIS 808-03.7.3 Vials, headspace, 20 mL (actual volume 21.5 mL). Toensure against extraneous peaks in the gas chromatographictraces, wash vials thoroughly and dry in a 125C air oven fora minimum of 4 h before using.7.4 Vial Crimp Caps.7.5 Septa, Polytetra
22、fluoroethylene (PTFE)/silicone. To en-sure that the septa are free of volatiles, cover the bottom of a15-cm petri dish with septa, PTFE-polymer side up. Micro-wave at full power for 10 min. Place microwaved septa into avacuum (greater than 29 in.) oven at 130C for 16 h.7.6 Crimping Tool for vials.7.
23、7 Syringe, 2 mL, gas-tight with valve. Store syringe in90C oven between uses.7.8 Gas Chromatograph equipped as follows:7.8.1 FID Detector, compatible with capillary columns.7.8.2 Injector, split/splitless compatible with capillary col-umns.7.8.3 Automated Headspace Sampler, Optional.7.8.4 Column, DB
24、-5, 30 m, 0.25-mm inside diameter, 1-mfilm thickness, or 0.32 mm. (A short piece of deactivated0.25-mm fused silica column may be placed between theinjector and the column to serve as a guard column.)7.8.5 Peak-Area Integration System compatible with GCsystem.Alternatively, a chart recorder and hand
25、 integration canbe used.7.9 Fluoroptic Thermometry System .7.10 Temperature Probes, high temperature.7.11 Beaker, 600 mL.7.12 Oven, hot air, set for 90C.7.13 Stopwatch.7.14 4-Heptanone.7.15 Standard SolutionsRegular Method:7.15.1 Internal Standard Solution (245 g/mL4-Heptanone)To approximately 950 m
26、L of distilled water ina 1-L volumetric flask add 300 L of 4-heptanone. Mix welland dilute to volume with water.7.15.2 Standard Solution 1: (Prepare fresh daily.)To ap-proximately 475 mL of internal standard solution in a 500-mLvolumetric flask, add 50 L of each of the compounds to bequantitated. Mi
27、x well, and dilute to volume with internal4McCown, S. M., and Radenheimer, P., “An Equilibrium Headspace GasChromatographic Method for the Determination of Volatile Residues in VegetableOils and Fats,” LC/GC, Vol 7, No. 11, 1989, pp. 918924.5McNeal, T. P., and Breder, C. V., “Headspace Gas Chromatog
28、raphic Determi-nation of Residual 1,3-Butadiene in Rubber-Modified Plastics and Its Migrationfrom Plastic Containers Into Selected Foods,” Journal of the Association ofAnalytical Chemists, Vol 70, No. 1, 1987, pp. 1821.6McNeal, T. P., and Breder, C. V., “Headspace Sampling and Gas-SolidChromatograph
29、ic Determination of Residual Acrylonitrile in Acrylonitrile Copoly-mer Solutions,” Journal of the Association of Offcial Analytical Chemists, Vol 64,No. 2, 1981, pp. 270275.TABLE 1 Analyte Recovery Without MicrowavingCompound ( n)ARecoveryMean, %WithinLaboratoryVariability, %OverallVariability, %Not
30、e(s)BBenzene 5 97.7 7.8 9.02-Butoxy-ethanol 4 98.7 6.7 8.4 1Dibutyl Ether 5 109.7 16.5 23.7Dodecane 3 101.1 10.7 10.7 1, 22-Furfural 4 99.7 11.7 12.0 1Furan-2-Methanol3 100.0 14.1 16.4 1, 3Isobutyl Alcohol 4 96.0 7.1 7.9 4MethyleneChloride5 103.5 16.7 22.62-Propanol 3 99.9 11.4 12.0 4Styrene 5 100.8
31、 8.5 9.3Toluene 4 102.7 9.9 10.9 4Overall 101.1 11.6 14.4An = number of laboratories submitting data on compound.BNotes: Collaborating laboratories provided the following reasons for not sub-mitting data on a particular analyte:1. The analyst felt interaction was occurring among various analytes and
32、 spentseveral days investigating. The laboratory manager refused to allow additionaltime for collaborative study.2. The analyst questioned the solubility of the analyte and did not add to thespike mixture.3. A fresh standard was not prepared fresh daily. This compound degradesmeasurably in water in
33、24 h.4. The analyst experienced coelution of peaks under conditions of collaborativestudy on his/her particular system.F1308 98 (2014)2standard solution. If difficulty is experienced with dissolutionof analyte, alternate standard solution procedure may over-come this difficulty.7.15.3 Standard Solut
34、ion 2Repeat 7.14.2 using 25 L ofeach compound.7.15.4 Standard Solution 3Repeat 7.14.2 using 10 L ofeach compound.7.16 Standard SolutionsAlternate Method:7.16.1 Alternate Internal Standard Solution (1225 g/mL4-Heptanone)To approximately 150 mL of helium-spargedorthodichlorobenzene (ODCB) in a 200-mL
35、volumetric flaskadd 300 Lof 4-heptanone. Mix well and dilute to volume withODCB.7.16.2 Alternate Standard Solution 1 To approximately 75mL of alternate internal standard solution in a 100-mL volu-metric flask, add 50 L of each of the compounds to bequantitated. Mix well, and dilute to volume with al
36、ternateinternal standard solution.7.16.3 Alternate Standard Solution 2 Repeat 7.15.2 using25 L of each compound.7.16.4 Alternate Standard Solution 3 Repeat 7.15.2 using10 L of each compound.7.17 Susceptor BlankObtain a representative sample ofsusceptor material to be tested. Bake in an air oven over
37、nightat 100C or higher to remove any volatile materials present.Store blank susceptor strips in humidity chamber 1 at 50 % RHand 23C until equilibrium moisture content is reached. Anexposure time of 24 h is generally adequate for most paper-based products. Strips should remain in the conditioningenv
38、ironment until needed for analysis.7.18 Syringe Needle, 13 gage.7.19 Variable Voltage Transformer, OptionalThis can oc-casionally be used for minor adjustments to line voltage tobring power output of the microwave oven into the specifiedrange.8. Instrument Setup8.1 Determine sample test conditions a
39、s follows:8.1.1 Set up microwave susceptor in the configuration of itsintended use, that is, a popcorn bag filled with popcorn, a pizzadisk with pizza on top, etc.8.1.2 Place temperature probes (7.10) on susceptor surface,disturbing the normal food load as little as possible. If thesusceptor has are
40、as where the food does not normally contactthe surface, place the probes in these areas. Place the productin the center of the microwave oven.8.1.3 Cook the product in accordance with normaldirections, for the maximum cooking time. Record this time.Record the probe temperature(s), preferably at 5-s
41、intervals,but at intervals not to exceed 15 s during cooking.8.1.4 Place 250 mL of room-temperature distilled water intoa 600-mL beaker. Place the beaker in the center rear of themicrowave oven.8.1.5 Cut a 10 by 65-mm (6.5-cm2= 1-in.2) portion fromthe susceptor sample to be tested. Insert carefully
42、into the20-mL headspace vial.8.1.6 Using a 13-gage syringe needle, pierce a hole into aheadspace vial septum. Place the septum on the vial and crimp.8.1.7 Insert one temperature probe (7.10) through the sep-tum hole into the vial and manipulate it until it is in contactwith the active face of the su
43、sceptor material. Place the vial onits side in the center of microwave oven, crimp end towardright of the oven, and susceptor with active face up.8.1.8 Microwave at full power, recording the probetemperature, preferably at 5-s intervals, but at intervals not toexceed 15 s.8.1.9 Plot the temperatures
44、 from 8.1.3 and 8.1.8 on the samegraph.8.1.10 Compare the plots. If the trace from 8.1.8 closelyapproximates or is slightly higher than the plot from 8.1.3 thenthe test time will be equal to the maximum product cook timeof the product in that oven. If the trace is substantially higheror lower than t
45、hat of the susceptor with product, then adjust themass or surface area, or both, (by changing container size) ofthe water (using a fresh sample of room temperature distilledwater) as necessary to achieve a similar profile. Record themass of water and type of container that gives the bestagreement be
46、tween the test sample and the product temperatureprofiles.8.2 Set up the gas chromatographic system to meet thefollowing criteria.8.2.1 Injector Temperature250C.8.2.2 Detector Temperature250C.8.2.3 Column Temperature:8.2.3.1 Initial40C for 4 min.8.2.3.2 ProgramAdjust to give a retention window of:(1
47、) At least 15 min for volatile compounds bracketed by2-propanol and dichlorobenzene, retention time for 2-propanolof approximately 3 min and retention time for dichlorobenzeneof approximately 20 min.(2) Providing a separation of Di-n-butyl ether and styrene ofR = 0.5 or greater. For a 30-m by 0.25-m
48、m column this isapproximately 4C/min with a nominal carrier flow of 1.5mL/min.8.2.4 Attenuation or sensitivity, or both, set to give aninternal standard peak height of 60 to 90% of full scale onrecorder or integrator.9. Sampling9.1 The sample of microwave susceptor selected for extrac-tion should be
49、 representative of the entire susceptor.9.2 The sample should be undamaged, that is, laminationintact, uncreased (unless this is normal configuration) andunaltered.9.3 Carefully cut a 10 by 65-mm (6.5 cm2= 1 in.2) portionfrom the susceptor. Carefully trim away any frayed edgesbefore testing. Store susceptor test strips in humidity chamber2 at 50 % RH and 23C until equilibrium moisture content isreached. An exposure time of 24 h is generally adequate formost paper-based products. Strips should remain in the condi-tioning environment u
