Quality Control of Sweeteners: Production, Handling, and Storage - Sweeteners: Nutritional Aspects, Applications, and Production Technology - page 275

Preparationofgumsamplesisdonebyplacingtheminalaskandextractingthemwithamix-
tureofglacialaceticacid,water,andchloroform.Hardorsoftcandysamplesareshakenwithwater
untildissolved(Biemer1989).Milkanddairyproductsarehomogenizedpriortoanalysis,andan
aliquotofahomogeneoussampleistransferredtoalask,followedbytheadditionofdistilledwater.
Themixtureisthoroughlystirred,allowedtostand,andtheniltered(Ni,Xiao,andKokot2009).
Sweeteners are determined in diet jams by mixing the jam with water, followed by mixture
sonicationandilteringthrougha0.45-mmilter(Boyce1999).Preservedfruitsareusuallyground
andhomogenized,weighedintoavolumetriclask,extractedultrasonically,anddilutedtovolume
withwateraftercoolingatroomtemperature.Avolumeofsupernatantisappliedtoaconditioned
Sep-PakC 18 cartridge(ChenandWang2001),andthesubsequentSPEstepfollows.
Beverages,juices,strawberrysweets,andtomatosaucecontainingacesulfameKand/oraspar-
tame can be analyzed with the use of a low injection analysis (FIA) system coupled with a UV
detector.Anadequateamountofbeverageistaken,degassed,diluted,sometimescentrifuged(asin
thecasesofjuices),andilteredthrougha0.2-mmMilliporeilter.Strawberrysweetsareweighed,
crushedinaglassmortar,dissolvedinwaterwiththeaidofanultrasonicbath,centrifuged,and
iltered.Finally,inthecaseoftomatosauce,aportionisdilutedinwater,centrifuged,andexposed
tothesameprocedureasforbeverages(Jiménez,Valencia,andCapitán-Vallvey2009).
Moreover, the pretreatment of a sample of soy sauce, dried roast beef, and sugared fruit
includesplacementinavolumetriclask,waterdilution,mixingthoroughly,andtheadditionofa
portionofthesolutiontoaSep-PakC 18 cartridge.Then,waterispassedthroughthecartridgeto
removetheinterferingsubstances.Otheradditivesareabsorbedontothepackingmaterial,eluted
with acetonitrile-water (2:3 v/v), and collected as eluate, which is then diluted to volume with
acetonitrile-water(2:3v/v;ChenandFu1995).
Fouriertransforminfrared(FTIR)spectroscopyisalsoaquickmethodforthedeterminationof
acesulfameKincommercialdietfoodsampleswithouttheuseofanextractionsteppriortoanaly-
sis.Sampleswithdificultfoodmatrices,suchaschocolatesyrup,coffeedrinks,coffeecreamer,
cranberryjuices,icecream,andinstantchocolatemilk,canbeeasilyanalyzed.Theicecreamsam-
pleisconvertedtoamixtureat60°Cinawaterbathwithcontinuousagitation.Allothersamples
areusedwithoutanypretreatment.Foodsamplesaremixedthoroughlywithultrapurewaterand
maintainedat40°Cinanincubator,followedbyultrasonication.CarrezI(3.6-gpotassiumhexacya-
noferratetrihydratedissolvedandmadeupto100-mldistilledwater)andCarrezIIreagent(7.2-g
zincsulphateheptahydratedissolvedin100-mldistilledwater)solutionsareaddedtosamples,fol-
lowedbycentrifugationat4°C.Supernatantsareseparatedusingasyringetoavoidthefatlayers
andareiltered.Thewater-solubleextractobtainedisdirectlypouredontothesurfaceofattenuated
totalrelectance(ATR-FTIR)accordingtoShimetal.(2008).
9.18 phYSICOCheMICaL MethODS
9.18.1 Capillary electrophoresis
Capacitively coupled contactless conductivity detection (C 4 D) is a relatively new approach for
detection on capillary electrophoresis (CE-C 4 D; Fracassi da Silva and do Lago 1998; Fracassi da
Silva,Guzman,anddoLago2002;Zemannetal.1998).CE-C 4 Dhasbeensuccessfullyappliedforthe
determinationofinorganicandorganiccompoundsinfood(Escarpaetal.2008;Richteretal.2005).
CE-C 4 DwasusedbyBergamo,daSilva,anddeJesus(2011)forasimple,rapid,andsimulta-
neous determination of aspartame, cyclamate, saccharin, and acesulfame K in commercial sam-
ples of soft drinks and tabletop sweetener formulations. A buffer solution containing 100 mmol
L_1 tris(hydroxymethyl)aminomethane (TRIS) and 10 mmol L_1 histidine (His) was used as a