Refr

igerat
ionandfreezi
ng-arecruci
alforkeepingourf oodf
reshl
onger
.I
tsl
owdownt he
chemicalandbiol
ogical
processesthatmakei tspoil
.Foodsl
ikemeat
,fi
sh,f
rui
ts,
andveggi
es
canstaygoodforaf ewextr
aday s,t
heycanlastf orweeksorevenmonthsi
fwef r
eezet
hem.

Microorgani
sms-likebacteri
a,yeasts,molds,andvi
rusesar eeverywherear
oundus.Itmakes
foodgobadbycausi ngoff
-f
lavors,
slimi
ness,andchangesi ntextur
eandappear ance.
When
keepingperi
shabl
ef oodsatwar mtemper atur
es,i
t'
sli
kegivingthesemi cr
oorganismsaper
fect
envir
onmenttogrowandspoi lourfood.
Thisiswhererefr
igerati
oncomesi nhandybecauseit
helpsslowdownt heirgrowthandkeepsourf oodfr
esherforlonger.

Bact
eri
a-ar
eusual
l
ytheonest
hatspoi
lfoodt
hemost
,especi
all
ywhent
hef
oodi
smoi
st.

Dryandaci
dicf
oods-
aren'
taswel
comi
ngt
obact
eri
a,butt
heycanst
il
lbeaf
fect
edbyy
east
s
andmolds.

Vir
uses-canalsocont
aminateourfood,especi
all
yifwe'
renotcar
eful
abouthy
gienepr
act
ices
l
ikewashingourhandsorseparat
ingrawandcookedf oods

Whenmi croor
ganismscont
aminateourfood,theystar
tadapt
ingtothei
rnewenvi
ronment
.At
fi
rst
,theymightnotgr
owmuch, whichiscal
ledthelagphase.
Butthen,t
heyent
eran
exponenti
algr
owthphase,wher
etheirpopul
ationcandoubleever
yhour
Thegr
owt
hofmi
croor
gani
smsi
nfooddependsonal
otoft
hings

•
food'
schemi
cal
makeup

•
pHl
evel

•t
emper
atur
e

•
humi
dit
y

Prev
enti
ngfoodspoi l
age,i
t'
snotjustaboutkeepingthingscoldbutalsounderstandi
nghow
micr
oorgani
smswor kandmakingsur et
heenv i
ronment sthatarenotideal
forthem togr
ow
andspoil
ourfood.Wecan'tchangethenaturalcharacteri
sti
csoffood,butwehav ewaysto
cont
rolt
heenvir
onmentt okeepourf oodsafe.Thisincludesthi
ngsli
keheating,
cool
ing,
&humidif
ying.

Heati
ng-i
scrucial
f orf
oodsaf et
yasi
tel
i
minat
eshar
mful
bact
eri
a,v
iruses,
andpar
asi
test
hat
cancausefoodborneil
lnesses.
Exampl
e:

CookingtoProperTemperatures:Cooki
ngfoodtothecorrecti
nter
nal
temperatur
eensures
pathogensaredest
roy
ed,withdiffer
entf
oodsrequi
ringspecif
ict
emperat
uresforsaf
ety
.
Cooling-i
sequal
lyi
mportantforfoodsafet
yasheating.
Exampl e:

Prevent
ingBacter
ialGrowth:Pr
opercooli
ngpr
event
sbact
eri
afr
om mul
ti
ply
ingr
api
dlyonf
ood,
reduci
ngtheri
skoff oodbor
neil
lnesses.

Humidify
ing-canplayar
oleinfoodsafety,
especi
all
yinenvi
ronmentswher
emai nt
aini
ngt
he
ri
ghthumidit
ylevel
siscr
ucialf
orpreserv
ingthequal
ityandsafet
yofcer
tai
nfoods.
Example:

Prev
entingDryingOut :Inenvi
ronmentswher efoodisstor
edorprepar
ed,mai nt
ainingadequate
humidi
tylev
elspr eventsfoodsfrom dry
ingout,whichcancompromisetheirt
exture,tast
e,and
over
all
quali
t y
Temperatur
ei salsoabi gfact
ori nhowfastmicroorgani
smsgrow.Microorgani
smsl ike
warmertemper atureusuall
y20-60°.Refr
iger
ati
ngfoodsat4degreesCelsiusorlowert ohelp
sl
owdownt heirgrowth.
Example:

Humi dit
y,ort heamountofwat erintheair-al
soaf fect
showmi cr
oorganismsgrow.I
fit
'stoo
humi d,moldcangr ow, especi
all
yincoldroomswher econdensati
onformsonwal l
sand
ceil
ings.Thi
scanbedanger ousifcontaminatedwat erdri
psontofood.
Diff
erentmicr oor
ganismsr eactdif
ferent
lytooxy gen.Someneedi ttogrow, whi
l
eotherscan'
t
growi nit
spr esence.Bycont r
oll
ingoxygenl evel
s,l
ikeinvacuum packaging,wecanstopsome
microorganismsf rom growing.

Aerobicbacter
ia(
bact eri
asneedsoxy gen):suchasEscher i
chiacoli,Baci
ll
ussubt i
li
s,
Pseudomonasaer uginosa,andMy cobacteri
um tubercul
osis.
Anaer obicmicroorganismsare
thosethatdonotrequi r
eoxygenfortheirgrowthandsur v
ival.I
nstead,theycant hri
vein
envir
onment swit
hlit
tletonooxygensuchasCl ostri
dium species(suchasCl ostri
dium
botul
inum andClostr
idium t
etani
),Bacteroi
desspecies,andsomespeci esofLact obacil
l
us

Threemai nmet hodst okeepourf oodsafe:preventingcontaminati

on,changingthe
envir
onmentt oinhibi
tgr owt h,anddestr
oyi
ngmi croorgani
smswi thheatorchemical s.
Preventingcontamination- stoppi
nghar mf
ul t
hingsf rom gett
ingint
oourfoodordr inks.It'
slike
keepingourfoodsaf etoeatanddr ink.Wedot hisbymaki ngsureourhands,cookingsur faces,
andut ensi
lsareclean.Weal sostorefoodproper l
y,l
ikekeepingrawmeatsepar atef rom other
foods,sogermsdon' tspr ead.
Changingt heenvir
onmenttoinhibi
tgrowth-i
samet hodusedi
nf oodsafetytopreventhar
mful
bacter
iafrom growingonfood.Byadjust
ingfactorsl
iketemper
ature,
humi dit
y,oraci
dit
ylevel
s,
wecancr eateconditi
onsthatar
enotsuitabl
eforbact er
iat
othr
ive.Thishelpskeepourfood
safetoeatandr educestheri
skoffoodborneil
lnesses.

Destr
oy i
ngmi cr
oorganismswit
hheatorchemi
cals-i
samethodinfoodsafety.Wecanuse
ei
therhightemperatur
esorspeci
alcl
eani
ngsol
uti
onstogetr
idofharmful
ger msonourfood.
Thisprocesshelpsmakesureourmealsar
esaf
etoeatandwon'tmakeussi ck.

Anot
hermet
hods:

Usef ilt
ersinv ent
il
ati
onsyst
emsandmai nt
ainposi
ti
veairpressurei
nfoodprocessingareast
o
preventcont aminati
on.
Regul arcleaningofdri
psystemsandavoi
dingcont
actbetweenr awandcookedf oodsal
so
helps.
Frozenf oodsmustbekeptat- 18degr
eesCelsi
usorlower,
andwemustbecar efulnotto
contami natethem duri
ngpackagi
ng.