On food and cooking the science and lore of the kitchen ( PDFDrive ) 579
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damagesthepectin.Failurescansometimes
berescuedbytheadditionofacommercial
liquidpectinpreparationand/orcreamof
tartarorlemonjuice,andabriefreboiling.
Toomuchacidcancauseweepingoffluid
fromanoverfirmgel.
Uncooked and Unsweetened “Preserves”
Modern preserve making has been
transformed by the availability of
concentrated pectin, extracted and purified
from citrus and apple wastes, which can be
added to any crushed fruit, cooked or not, to
guaranteeafirmgel.“Freezerjams”aremade
by loading up crushed fresh fruit with
supplemental pectin and sugar, letting them
sitforadaywhilethepectinmoleculesslowly
formtheirnetworkandformthegel,andthen
“preserving” them in the refrigerator or
freezer (the uncooked fruit would otherwise
soon be spoiled by sugar-tolerant molds and
yeasts).Pectinisalsousedtomakeclearjelly
candiesandotherconfections.
Foodchemistshavedevelopedseveral
differentversionsofpectinforspecial
commercialapplications.Themostnotableof
theseisapectinthatsetswithouttheneedfor
anyaddedsugartopullwatermoleculesaway
fromthelongpectinchains;instead,the
chainsbondtoeachotherstronglybymeans
ofcross-linkingcalcium,whichisaddedafter
thefruitandpectinmixturehasbeencooked.
Thispectiniswhatmakesitpossibleto
producelow-calorie“preserves”with
artificialsweeteners.
Candied Fruits Candied fruits are small
whole fruits or pieces that are impregnated
with a saturated sugar syrup, then drained,
dried, and stored at room temperature as
separatepieces.Fruitcookedinasugarsyrup
remains relatively firm and maintains its
shape thanks to the interaction of sugar
molecules with the cell-wall hemicelluloses
