On food and cooking the science and lore of the kitchen ( PDFDrive ) 1484
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compounds,notablytheoxidesofsilicon,
aluminum,andmagnesium.Glassisa
particularvarietyofceramicwhose
compositionismoreregular,andusually
includesapreponderanceofsilica(silicon
dioxide).Untilfairlyrecently,thesematerials
weremadefromnaturallyoccurringmineral
aggregates:thewordceramiccomesfromthe
Greekfor“potter’sclay.”Themoldingand
dryingofsimpleclaypottery,orearthenware,
datesfromabout9,000yearsago,oraboutthe
timethatplantsandanimalswerefirst
domesticated.Lessporousandcoarsethan
earthenware,andmuchstronger,isstoneware,
whichcontainsenoughsilicaandisfiredata
highenoughtemperaturethatitvitrifies,or
becomespartlyglass.TheChineseinvented
thisrefinementsometimebefore1500BCE.
Porcelainisawhitebuttranslucentstoneware
madebymixingkaolin,averylightclay,with
asilicatemineral,andfiringathighkiln
temperatures;itdatesfromtheT’angDynasty
(618–907CE).Thisfineceramicwas
introducedtoEuropewiththeteatradeinthe
17thcentury,andinEnglandwasfirstcalled
“Chinaware,”andthensimply“China.”The
firstglasscontainerswerenotmoldedor
blown,butlaboriouslysculptedfromblocks,
anddatefrom4,000yearsagointheNear
East.
TheQualitiesofCeramicPotsThe
outstandingcharacteristicofceramic
materialsischemicalstability:theyare
unreactive,resistcorrosion,anddon’taffect
theflavororotherqualitiesoffoods.(One
exceptiontothisruleisthefactthatclaysand
glazessometimescontainlead,whichisa
nervepoison,andwhichcanbeleachedout
intoacidicfoods.Importedceramic
containersmadewithhigh-leadclaysor
glazesstilloccasionallycausecasesoflead
poisoning.)Ceramicpotstendtobeusedonly
inslow,uniformcookingprocesses,
especiallyovenbakingandbraising,because
