Avcntp Texts

7/23/2019 Avcntp Texts

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UNIT 1: WHAT IS FOOD SCIENCE?

Food Science and Technology is a convenient nae !sed to desc"i#e the a$$lication o%scienti%ic $"inci$les to c"eate and aintain a &holesoe %ood s!$$ly' Food Science has given !s

%"o(en %oods) canned %oods) ic"o&ave eals) il* &hich does not need "e%"ige"ation) easily

$"e$a"ed t"aditional %oods and) a#ove all) va"iety in o!" diets' The Food Scientist lea"ns and

a$$lies a &ide "ange o% scienti%ic *no&ledge to aintain a high +!ality) a#!ndant %ood s!$$ly'Food Science allo&s !s to a*e the #est !se o% o!" "eso!"ces in a s!staina#le anne" and

inii(e &aste'

To #e a Food Scientist and hel$ handle the &o"ld,s %ood s!$$ly to a-i! advantage)yo! need soe %ailia"ity in a n!#e" o% disci$lines incl!ding the a$$lication o% ic"o#iology)

cheist"y) as$ects o% #iocheist"y and soe s$eciali(ed statistics' The investigation o% ho&

#iological ate"ials #ehave in ha"vesting) $"ocessing) dist"i#!tion) sto"age and $"e$a"ation isco$le- and %!ll a&a"eness o% all i$o"tant as$ects o% the $"o#le "e+!i"es #"oad.#asedt"aining'

With the s$ecial t"aining in the a$$lied science *no&n as Food Science) a &ide "ange o%

e$loyent o$$o"t!nities e-ist %o" the t"ained $"o%essional' E-a$les incl!de the /"od!ctDevelo$ent S$ecialist) Senso"y Scientist) 0!ality Cont"ol and 0!ality Ass!"ance S$ecialist)

Technical Sales S$ecialist) esea"ch and Develo$ent Scientist) 2a"*eting) Cons!e" 3ehavio"

and 2anageent to nae a %e&' Food Science can lead to any e-citing and $"od!ctive

ca"ee"s'

A n!#e" o% inte"esting and !ni+!e o$tions in the Food Science and Technology $"og"aincl!de:

Food /"ocessing

/"od!ct Develo$entFood Cheist"y

Food 2ic"o#iology

Food 0!ality 2anageent3iocheist"y

2a"*eting and Cons!e" 3ehavio"

H!an eso!"ce 2anageent and Ind!st"ial elations

Asian St!dies3!siness 2anageent

Why does there seem to be so much chemistry in Food Science? What if I haven't done well

in this subject before?

Food Science "e+!i"es a#o!t the sae ao!nt o% #asic science as othe" science $"og"as'The di%%e"ence is that in Food Science eve"y st!dent gets an e-$os!"e to a &ide "ange o%


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scienti%ic disci$lines and has a chance to s!cceed in o"e a"eas' The cheist"y yo! st!dy in the

$"og"a is not $!"e cheist"y #!t a$$lied cheist"y e'g' in st!dying the %o"ation o% alcohol

d!"ing a &ine %e"entation o" the %lavo" co$onents o% co%%ee' Food Science classes then allo&the st!dent to a$$ly those #asic ideas lea"ned in gene"al science classes'

QUESTI!S

1' What do yo! *no& a#o!t Food Science and Technology?

4' As a Food Scientist) &hat s$eciali(ed s!#5ects do yo! need a$$ly?6' A%te" the t"aining co!"se in Food Science) &hat 5o#s can yo! get?

7' 8ist soe o$tions in the Food Science and Technology $"og"a'

9' Is it "ight i% cheist"y that yo! st!dy in the $"og"a is $!"e cheist"y?

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U!IT "# $%&()*&%TES

Ca"#ohyd"ates a*e !$ a g"o!$ o% cheical co$o!nds %o!nd in $lant and anial cells'

They have the e$i"ical %o"!la CnH4nOn) o" CH4O;n' An e$i"ical %o"!la tells the atoicco$osition o% the co$o!nd) #!t nothing a#o!t st"!ct!"e) si(e) o" &hat cheical #onds a"e

$"esent' Since this %o"!la is essentially a co#ination o% ca"#on and &ate") these ate"ials a"e

called


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chain the ca"#onyl g"o!$ is the ca"#on do!#le.#onded to o-ygen;'The n!#e" o% ca"#ons in the

olec!le gene"ally catego"i(es onosaccha"ides' Fo" e-a$le) th"ee.ca"#on ca"#ohyd"ate

olec!les a"e called t"ioses) %ive.ca"#on olec!les a"e called $entoses) and si-.ca"#on olec!lesa"e called he-oses'

One o% the ost i$o"tant onosaccha"ides is gl!cose de-t"ose;' This olec!le is the$"ia"y so!"ce o% cheical ene"gy %o" living systes' /lants and anials ali*e !se this olec!le

%o" ene"gy to ca""y o!t cell!la" $"ocesses' 2aals $"od!ce $e$tide ho"ones ins!lin andgl!cagon; that "eg!late #lood gl!cose levels) and a disease o% high #lood gl!cose is called

dia#etes' Othe" he-oses incl!de %"!ctose %o!nd in %"!it 5!ices; and galactose'

Di%%e"ent st"!ct!"es a"e $ossi#le %o" the sae onosaccha"ide' Altho!gh gl!cose and%"!ctose a"e identical in cheical co$osition CH14O;) they a"e ve"y di%%e"ent in st"!ct!"e'

S!ch ate"ials a"e called isoe"s' Isoe"s in gene"al have ve"y di%%e"ent $hysical $"o$e"ties

#ased on thei" st"!ct!"e'

*isaccharides

Disaccha"ides a"e t&o onosaccha"ide s!ga" olec!les that a"e cheically 5oined #y a

glycosidic lin*age . O .; to %o" a


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Sta"ch is the $"edoinant sto"age olec!le in $lants and $"ovides the a5o"ity o% the

%ood calo"ies cons!ed #y $eo$le &o"ld&ide' 2ost sta"ch g"an!les a"e co$osed o% a i-t!"e

o% t&o $olye"s: a linea" $olysaccha"ide called aylose and a #"anched.chain $olysaccha"idecalled aylo$ectin' Aylo$ectin chains #"anch a$$"o-iately eve"y [email protected] saccha"ide !nits'

Aylo$ectin is the o"e coon %o" o% sta"ch %o!nd in $lants' Anials sto"e ene"gy in the

!scles and live" as glycogen' This olec!le is o"e highly #"anched than aylo$ectin' Fo"longe".te" sto"age) anials conve"t the %ood calo"ies %"o ca"#ohyd"ates to %at' In the h!an

and anials) %ats a"e sto"ed in s$eci%ic $a"ts o% the #ody called adi$ose tiss!e'

Cell!lose is the ain st"!ct!"al co$onent o% $lant cell &alls and is the ost a#!ndant

ca"#ohyd"ate on ea"th' Cell!lose se"ves as a so!"ce o% dieta"y %i#e" since) as e-$lained #elo&)h!ans do not have the intestinal en(yes necessa"y to digest it'

Sta"ch and cell!lose a"e #oth hoo$olye"s


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also !sed to sta#ili(e dis$e"sions) s!s$ensions) and e!lsions in %oods li*e ice c"ea) in%ant

%o"!las) dai"y desse"ts) c"eay salad d"essings) 5ellies and 5as) and candy' Sta"ches a"e !sed

as #inde"s) adhesives) oist!"e "etaine"s) te-t!"i(e"s) and thic*ene"s in %oods'

QUESTI!S#

1' What a"e onosaccha"ides?

4' What is the ost i$o"tant onosaccha"ides? What is its "ole?

6' E-$lain the te" isoe"s'

7' What a"e disaccha"ides? ive soe e-a$les o% disaccha"ides'

9' Ho& is inve"t s!ga" c"eated?

' What a"e $olysaccha"ides? ive soe e-a$les o% $olysaccha"ides'

' What a"e sta"ch g"an!les co$osed o%?

' Can h!an digest sta"ch o" cell!lose? Why?

' What a"e the i$o"tant "oles o% ca"#ohyd"ates in %ood $"ocessing?

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U!IT -# ,&TEI!S

/"oteins a"e the ost co$le- and i$o"tant g"o!$ o% olec!les #eca!se they $ossess

dive"se %!nctionality to s!$$o"t li%e' Eve"y cell that a*es !$ $lants and anials "e+!i"es

$"oteins %o" st"!ct!"e and %!nction' En(yes) s$eciali(ed $"oteins) cataly(e cheical "eactions

that a"e necessa"y %o" eta#olis and cell "e$"od!ction' O!" !scles a"e ade %"o a va"iety o%

$"oteins) and these $"oteins allo& o!" !scles to cont"act) %acilitating oveent' Othe" ty$es o%$"oteins in o!" #ody a"e the $e$tide ho"onesG ins!lin and gl!cagon a"e t&o coon e-a$les'

/"oteins a"e co$le- $olye"s co$osed o% aino acids' Aino acids contain ca"#on)

hyd"ogen) nit"ogen) and soeties s!l%!" and se"ve as the onoe"s %o" a*ing $e$tides and$"oteins' Aino acids have a #asic st"!ct!"e that incl!des an aino g"o!$ NH4; and a ca"#o-yl

g"o!$ COOH; attached to a ca"#on ato' This ca"#on ato also has a side chain an


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The"e a"e t&enty aino acids %o!nd in the #ody' Eight o% these aino acids a"e essential

%o" ad!lts and child"en) and nine a"e essential %o" in%ants' Essential eans that &e cannot

synthesi(e the in ade+!ate +!antities %o" g"o&th and "e$ai" o% o!" #odies) and the"e%o"e) !st#e incl!ded in the diet'

Aino acids a"e lin*ed togethe" #y a $e$tide #ond in &hich the ca"#o-yl ca"#on o% oneaino acid %o"s a covalent #ond &ith the aino nit"ogen o% the othe" aino acid' Sho"t chains

o% aino acids a"e called $e$tides' 8onge" chains o% aino acids a"e called $oly$e$tides'Altho!gh the te" $oly$e$tides sho!ld incl!de $"oteins) chains &ith less than 1@@ aino acid

"esid!es a"e conside"ed to #e $oly$e$tides) &hile those &ith 1@@ o" o"e aino acid "esid!es a"e

conside"ed to #e $"oteins'

2any o% the a5o" ho"ones in the #ody a"e $e$tides' These ho"ones can in%l!ence

en(ye action) eta#olis) and $hysiology' Ce"tain anti#iotics and a %e& anti.t!o" agents a"e

also $e$tides' The a"ti%icial s&eetene" as$a"tae is a di$e$tide co$osed o% as$a"tic acid and

$henylalanine &ith a ethyl g"o!$ attached at the ca"#o-yl te"inal g"o!$ 8.as$a"tyl.8.

$henylalanine ethyl este";'

The se+!ence o% aino acid "esid!es in a $oly$e$tide chain is c"itical %o" #iological

%!nction' A single st"!ct!"al change "es!lted in a d"aatic alte"ation in $hysiological %!nction'

The a#ility o% an en(ye to cataly(e a $a"tic!la" "eaction de$ends on its s$eci%ic sha$e' Its a lotli*e a *ey and loc*G i% the *ey is #"o*en o" in a di%%e"ent sha$e) it &ont o$en the loc*' The

"ece$to" sites on cell s!"%aces !st #e in a s$eci%ic sha$e %o" $oly$e$tide ho"ones to inte"act

&ith the cell' With t&enty di%%e"ent aino acids and each $oly$e$tide consisting o% h!nd"eds o%aino acids) it is no &onde" that $"oteins $lay s!ch a va"iety o% "oles in the h!an #ody'

$hemistry of ,roteins

The $"otein #ac*#one is %o"ed %"o the $e$tide #onds c"eated %"o the aino and

ca"#o-yl g"o!$s o% each onoe" that "e$eat the $atte"n .N.C.C. o" C.C.N.' The n!#e" andse+!ence o% aino acids in a $oly$e$tide chain is "e%e""ed to as the $"ia"y st"!ct!"e o% a

$"otein' The %"ee aino g"o!$ and ca"#o-yl g"o!$ on o$$osite ends o% a $oly$e$tide chain allo&

$"oteins to act as $H #!%%e"s "esist changes in $H; inside the cell' The aino g"o!$ NH4;acce$ts a $"oton and #ecoes NH6> ;) and the ca"#o-yl g"o!$ COOH; donates a $"oton and

#ecoes dissociated COO.;'

As noted $"evio!sly) each aino acid "esid!e in the $olye" ay have a di%%e"ent sidechain o" cheical g"o!$ attached to it) s!ch as hyd"o-yl OH;) aino NH4;) a"oatic "ingcon5!gate "ings s!ch as the $henol "ing in $henylalanine;) s!l%hyd"yl SH;) ca"#o-yl COOH;)

o" va"io!s al*yl CHn;' This va"iety o% side chain g"o!$s on the $olye" #ac*#one gives $"oteins

"ea"*a#le cheical and $hysical $"o$e"ties' Fo" e-a$le) ca"#o-ylate g"o!$s can %!nction asca"#o-ylic acids COO.;) o" aino g"o!$s can #ehave as #ases NH6>;' This allo&s $"otein

$olye"s to #e !lti%!nctional olec!les) &ith #oth acidic and #asic #ehavio" at the sae tie

Additionally) the $"esence o% hyd"o-yls) ca"#o-ylates) s!l%hyd"yls) and aino g"o!$s allo&s


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hyd"ogen #onding) and the al*yl g"o!$s $"ovide hyd"o$ho#ic inte"actions) #oth &ithin the

$"otein $olye" itsel% and #et&een se$a"ate $"otein olec!les'

In the case o% ac"oolec!les) s!ch as $"oteins) the $olye"ic st"!ct!"e o% theac"oolec!le allo&s it to si!ltaneo!sly ca""y any di%%e"ent cha"ges on di%%e"ent aino acid

"esid!es;' Ho&eve") !nli*e the sall single olec!les) the aino acid "esid!es a"e const"ained#y linea" $e$tide lin*ages and th!s cannot ove %"eely to "andoly associate &ith othe" cha"ged

olec!les' Ass!ing that cha"ged "esid!es &ill see* to #ond &ith the nea"est convenient co!nte"ion) it is ost li*ely that o$$ositely cha"ged aino acid "esid!es located at di%%e"ent $oints

&ithin a single $"otein chain &ill #ond' These st"!ct!"al di%%e"ences "es!lt in the %olding o%

$"oteins into a th"ee.diensional st"!ct!"e) &hich is) in $a"t) "es$onsi#le %o" thei" %!nctional$"o$e"ties as #iocatalysts) st"!ct!"al ate"ials) !scles) and cheical "ece$to"s' /"oteins can #e

sha$ed as long %lat sheets o" in glo#!la" s$he"es' This leads to the naes %i#"o!s o" glo#!la" %o"

$"otein sha$es' 2ost en(yes a"e glo#!la" $"oteins'

In standa"d acid #ase cheist"y) &e *no& that olec!les ca""y elect"ostatic cha"ges #ased

on the ty$e o% atos that a*e !$ a olec!le and the envi"onent o% the olec!le' iven thato$$osite cha"ges att"act) cationic and anionic atos can co#ine to %o" covalent #onds) in

&hich elect"ons a"e sha"ed #et&een atoic o"#itals) o" %o" ionic #onds) in &hich onlyelect"ostatic att"actions e-ist' In sol!tion &ith salle" olec!les) s!ch as HCl an acid; o" NaOH

a #ase;) $"otein olec!les can %"eely ove a"o!nd and associate &ith each othe" on a o"e.o".

less "ando #asis'

/"otein $olye"s e-tend the si$le acid #ase cha"ged cheical s$ecies conce$ts toe-$lain ho& #iological systes have g"eate" levels o% co$le-ity and can !tili(e si$le)

onoe"ic cheical st"!ct!"es li*e aino acids; to c"eate e-+!isitely co$le- #iological

st"!ct!"es li*e anti#odies) !scle) and s*in' /"otein $olye"s have $hysical st"!ct!"e) even &hen

dissolved in li+!ids' The cha"ged and hyd"o$ho#ic "esid!es &ithin a $"otein tend to associate)ca!sing the $"otein to %old !$' When yo! !n%old the $"otein olec!le called denat!"ation;) its

cha"ged "esid!es can "eassociate &ith othe" cha"ged olec!les $"eci$itation o" coag!lation;'/"otein $"eci$itation is &idely !sed to "ecove" "eco#inant $"otein $"od!cts) en(yes) o" in the

$"od!ction o% any coon %oods' Cheeses and soy#ean to%! a"e e-a$les o% coag!lated

$"otein %ood $"od!cts'

Food Uses of ,roteins

/"oteins also se"ve i$o"tant "oles in the $"ocessing o% %ood $"od!cts' They a"e !sed %o"thei" thic*ening) gelling) e!lsi%ying) and &ate".#inding $"o$e"ties in eats sa!sages;) #a*e"y

$"od!cts) cheese) desse"ts) and salad d"essings' /"oteins a"e !sed %o" thei" cohesive and adhesive

$"o$e"ties in sa!sage a*ing) $asta) and #a*ed goods' Egg $"oteins a"e !sed %o" thei" %oaing$"o$e"ties in desse"ts) ca*es) and &hi$$ed to$$ings' 2il*) egg) and ce"eal $"oteins a"e !sed as %at

and %lavo" #inde"s in lo&.%at #a*e"y $"od!cts' /"oteins a"e !sed %o" te-t!"e and $alata#ility in

#a*e"y $"od!cts #"eads) ca*es) c"ac*e"s) and $i((a c"!st; and sa!sages'


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2il* $"otein consists o% @J casein and 4@J &hey $"oteins' The"e a"e %o!" a5o" ty$es

o% casein olec!les: al$ha.s1) al$ha.s4) #eta) and *a$$a' 2il*) in its nat!"al state) is negatively

cha"ged' The negative cha"ge $e"its the dis$e"sion o% casein in the il*' When an acid is addedto il*) the H> concent"ation ne!t"ali(es the negatively cha"ged casein icelles' When il* is

acidi%ied to $H 7') the isoelect"ic $oint the $oint at &hich all cha"ges a"e ne!t"al; o% casein) an

isoelect"ic $"eci$itate *no&n as acid casein is %o"ed' Cottage cheese and c"ea cheesean!%act!"e involves an acid $"eci$itation o% casein &ith lactic acid o" lactic acid $"od!cing

ic"oo"ganiss' Acid casein is !sed in the cheical ind!st"y and as a gla(ing additive in $a$e"

an!%act!"ing'

Casein also can #e coag!lated &ith the en(ye "ennin) &hich is %o!nd in "ennet ane-t"act %"o the stoach o% calves;' ennin &o"*s #est at #ody te$e"at!"e 6KC;' I% the il* is

too cold) the "eaction is ve"y slo&) and i% the il* is too hot) the heat &ill denat!"e the "ennin)

"ende"ing it inactive' The echanis %o" the coag!lation o% the casein #y the "ennin is di%%e"ent%"o the acid $"eci$itation o% casein' The "ennin coag!l! consists o% casein) &hey $"otein) %at)

lactose) and the ine"als o% the il*) and has a %l!%%ie" and s$ongie" te-t!"e than the acid

$"eci$itate' ennet is !sed in the an!%act!"e o% cheese and cheese $"od!cts) and "ennet casein is!sed in the $lastics ind!st"y' Casein is sol!#ili(ed &ith sodi! hyd"o-ide and calci! hyd"o-ide

to $"od!ce sodi! caseinate and calci! caseinate) "es$ectively' Caseinates a"e added to %ood

$"od!cts to inc"ease thei" $"otein content and a"e *ey ing"edients in non.dai"y co%%ee c"eae"s'

A$$"o-iately @J o% soy#ean $"oteins a"e classi%ied as glo#!lins) #ased on thei"sol!#ility in salts' 2o"e s$eci%ically) the $"oteins a"e conglycinin a glyco$"otein; and glycinin'

To%! is an!%act!"ed #y coag!lating the $"oteins in soyil* &ith agnesi! s!l%ate' As

#onding occ!"s #et&een the $ositively cha"ged agnesi! ions and negatively cha"ged anionic

g"o!$s o% the $"otein olec!les) the $"oteins coag!late'

QUESTI!S

1' What a"e $"oteins?

4' Why a"e $"oteins i$o"tant g"o!$ o% olec!les?

6' Desc"i#e a #asic st"!ct!"e o% aino acid'

7' What does essential aino acid ean?

9' Ho& a"e aino acids lin*ed togethe" in $"otein olec!le?

' Disting!ish the te"s


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U!IT .# E!/)+ES

8iving systes contain la"ge $"otein olec!les called en(yes' Those la"ge glo#!la"$"oteins "ange in olec!la" &eight %"o a#o!t 1@)@@@ to seve"al illion' Each o% the tho!sands

o% *no&n en(yes has a cha"acte"istic th"ee. diensional sha$e &ith a s$eci%ic s!"%ace

con%ig!"ation as a "es!lt o% its $"ia"y) seconda"y) and te"tia"y st"!ct!"es' The !ni+!econ%ig!"ation o% each en(ye ena#les it to


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6' The s!#st"ate olec!le is t"ans%o"ed #y the "ea""angeent o% e-isting atos) the

#"ea*do&n o% the s!#st"ate olec!le) o" co#ination &ith anothe" s!#st"ate olec!le'

7' The t"ans%o"ed s!#st"ate olec!les L the $"od!cts o% the "eaction L a"e "eleased %"o

the en(ye olec!le #eca!se they no longe" %it in the active site o% the en(ye'

9' The !nchanged en(ye is no& %"ee to "eact &ith othe" s!#st"ate olec!les'

En(yes a"e e-t"eely e%%icient' Unde" o$ti! conditions) they can cataly(e "eaction

at "ates 1@ to 1@1@ ties !$ to 1@ #illion ties; highe" than those o% co$a"a#le "eactions

&itho!t en(yes'

In living cells) en(yes se"ve as #iological catalysts' As catalysts) en(yes a"e s$eci%ic'

Each acts on a s!#st"ate o" s!#st"ates) &hen the"e a"e t&o o" o"e "eactants;) and each cataly(es

only one "eaction' Fo" e-a$le) a s$eci%ic en(ye ay #e a#le to hyd"oly(e a $e$tide #ond only

#et&een t&o s$eci%ic aino acids' Othe" en(yes can hyd"oly(e sta"ch #!t not cell!loseG even

tho!gh #oth sta"ch and cell!lose a"e $olysaccha"ides co$osed o% gl!cose s!#!nits) the

o"ientation o% the s!#!nits in the t&o $olysaccha"ides di%%e"' En(yes have this s$eci%icity

#eca!se the th"ee diensional sha$e o% the active site %its the s!#st"ate soe&hat as a loc* %its

&ith its *ey' Ho&eve") the active site and s!#st"ate a"e %le-i#le) and they change sha$e soe&hat

as they eet to %it togethe" o"e tightly' The s!#st"ate is !s!ally !ch salle" than the en(ye)

and "elatively %e& o% the en(yes aino acids a*e !$ the active site'

A ce"tain co$o!nd can #e a s!#st"ate %o" a n!#e" o% di%%e"ent en(yes that cataly(e

di%%e"ent "eactions) so the %ate o% a co$o!nd de$ends on the en(yes that acts !$on it' l!cose

.$hos$hate) a olec!le that is i$o"tant in cell eta#olis) can #e acted !$on #y at least %o!"

di%%e"ent en(yes) and each "eaction &ill yield a di%%e"ent $"od!ct'

Factors influence en0yme activity

Seve"al %acto"s in%l!ence the activity o% en(ye' The o"e i$o"tant a"e te$e"at!"e)

$H) s!#st"ate concent"ation) and $"esence o" a#sence o% inhi#ito"s'

The "ate o% ost cheical "eactions inc"eases as the te$e"at!"e inc"eases' 2olec!les

ove o"e slo&ly at lo&e" te$e"at!"es than at highe" te$e"at!"es and so ay not have

eno!gh ene"gy to ca!se a cheical "eaction' Fo" en(yatic "eactions) ho&eve") elevation #eyond

a ce"tain te$e"at!"e d"astically "ed!ces the "ate o% "eaction' This dec"ease is d!e to the

en(yes denat!"ation) the loss o% its cha"acte"istic th"ee.diensional st"!ct!"e te"tia"y

con%ig!"ation;' Denat!"ation o% a $"otein involves #"ea*age o% hyd"ogen #onds and othe"

noncovalent #onds' As ight #e e-$ected) denat!"ation o% an en(ye changes the a""angeento% the aino acids in the active site) alte"ing its sha$e and ca!sing the en(ye to lose its catalytic

a#ility' In soe cases) denat!"ation is $a"tially o" %!lly "eve"si#le' Ho&eve") i% denat!"ation

contin!es !ntil the en(ye has lost its sol!#ility and coag!lates as &ith coo*ed al#!in; the

en(ye cannot "egain its o"iginal $"o$e"ties' En(yes can #e denat!"ed #y concent"ated acids)

#ases) heavy.etal ions s!ch as lead) a"senic) o" e"c!"y;) alcohol) and !lt"aviolet "adiation'


11/19

2ost en(yes have an o$ti! $H at &ith thei" activity is cha"acte"istically a-ial'

A#ove o" #ello& this $H val!e) en(ye activity) and the"e%o"e the "eaction "ate) declines' When

the H>concent"ation $H; in the edi! is changed) any o% the en(yes aino acids a"e

e%%ected and the $"oteins th"ee.diensional st"!ct!"e is alte"ed' E-t"ee changes in $H can

ca!se denat!"ation'

The"e is a a-i! "ate at &hich a ce"tain ao!nt o% en(ye can cataly(e a s$eci%ic

"eaction' Only &hen the concent"ation o% s!#st"ates; is e-t"eely high can this a-i! "ate

#e attained' Unde" condition o% high s!#st"ate concent"ation) the en(ye is said to #e sat!"ationG

that is) its active site is al&ays occ!$ied #y s!#st"ate o" $"od!ct olec!les' In this condition) a

%!"the" inc"ease in s!#st"ate concent"ation &ill not e%%ect the "eaction "ate #eca!se all active sites

a"e al"eady in !se' I% a s!#st"ates concent"ation e-ceeds a cells sat!"ation level %o" a $a"tic!la"

en(ye) the "ate o% "eaction can #e inc"eased only i% the cell $"od!ces additional en(ye

olec!les' Ho&eve") !nde" no"al cell!la" conditions) en(yes a"e not sat!"ated &ith

s!#st"ates;' At any given tie) any o% the en(ye olec!les a"e inactive %o" lac* o% s!#st"ateG

th!s) the "ate o% "eaction is li*ely to #e in%l!enced #y the s!#st"ate concent"ation'

En(ye inhi#ito"s a"e classi%ied acco"ding to thei" echanis o% action as eithe"

co$etitive o" nonco$etive inhi#ito"s' Co$etitive inhi#ito"s %ill the active site o% an en(ye

and co$ete &ith the no"al s!#st"ate %o" the active site' A co$etitive inhi#ito" is a#le to do

this #eca!se its sha$e and cheical st"!ct!"e a"e siila" to those o% no"al s!#st"ate' Ho&eve")

!nli*e the s!#st"ate) it does not !nde"go any "eaction to %o" $"od!cts' Soe co$etitive

inhi#ito"s #ind i""eve"si#ly to aino acids in the active site) $"eventing any %!"the" inte"actions

&ith the s!#st"ate' Othe"s #ind "eve"si#ly) alte"nately occ!$ying and leaving the active site) these

slo& the en(yes inte"action &ith the s!#st"ate' eve"si#le co$etitive inhi#ition can #e

ove"coe #y inc"easing the s!#st"ate concent"ation' As active site #ecoes availa#le) o"es!#st"ate olec!les than co$etitive inhi#ito" olec!les a"e availa#le to attach to the active sites

o% en(yes' Nonco$etitive inhi#ito"s do not co$ete &ith the s!#st"ate %o" the en(yes active

siteG instead) they inte"act &ith anothe" $a"t o% the en(ye' In this $"ocess) called alloste"ic


12/19

QUESTI!S#

1' What do en(yes gene"ally consist o%?

4' What can the co%acto" #e?

6' Ho& do coen(yes &o"*?

7' What is the i$o"tant "ole o% en(ye?

9' Desc"i#e the gene"al se+!ence o% events in en(ye "eaction'

' Why en(yes have thei" o&n s$eci%icity?

' Can a ce"tain co$o!nd #e a s!#st"ate %o" a n!#e" o% di%%e"ent en(yes that cataly(e

di%%e"ent "eactions?

' What a"e the i$o"tant %acto"s that in%l!ence the activity o% en(ye?

' What does denat!"ation o% a $"otein involve?

1@' What does denat!"ation o% an en(ye ca!se?

11' 3y &hat %acto"s can a""angeent en(yes #e denat!"ed?

14' When the en(ye is said to #e sat!"ation?

16' Ho& a"e en(ye inhi#ito"s classi%ied?

U!IT 1# STE&I2I/%TI! 3E&SUS ,%STEU&I/%TI!

The"al $"ocessing cove"s the #"oad a"ea o% %ood $"ese"vation technology in &hich heatt"eatents a"e !sed to inactivate ic"oo"ganiss to acco$lish eithe" coe"cial ste"ili(ation o"

$aste!"i(ation' Ste"ili(ation $"ocesses a"e !sed &ith canning to $"ese"ve the sa%ety and

&holesoeness o% "eady.to.eat %oods ove" long te"s o% e-tended sto"age at no"al "oote$e"at!"e non"e%"ige"ated; &itho!t additives o" $"ese"vatives) and $aste!"i(ation $"ocesses a"e

!sed to e-tend the "e%"ige"ated sto"age li%e o% %"esh %oods' Altho!gh #oth $"ocesses a*e !se o%

heat t"eatents %o" the $!"$ose o% inactivating ic"oo"ganiss) they di%%e" &idely &ith "es$ect tothe classi%ication o" ty$e o% ic"oo"ganiss ta"geted) and th!s the "ange o% te$e"at!"es that

!st #e !sed and the ty$e o% e+!i$ent systes ca$a#le o% achieving s!ch te$e"at!"es'

SE$TI! I# ,%STEU&I/%TI!

/aste!"i(ation is a "elatively ild heat t"eatent given to %oods &ith the $!"$ose o%

dest"oying selected vegetative ic"o#ial s$ecies es$ecially the $athogens; and inactivating the

en(yes' 3eca!se the $"ocess does not eliinate all the vegetative ic"o#ial $o$!lation and

alost none o% the s$o"e %o"e"s) $aste!"i(ed %oods !st #e contained and sto"ed !nde"conditions o% "e%"ige"ation &ith cheical additives o" odi%ied atos$he"e $ac*aging) &hich

inii(e ic"o#ial g"o&th' De$ending on the ty$e o% $"od!ct) the shel% li%e o% $aste!"i(ed %oodsco!ld "ange %"o seve"al days il*; to seve"al onths %"!it 5!ices;' 3eca!se only ild heat

t"eatent is involved) the senso"y cha"acte"istics and n!t"itive val!e o% the %ood a"e inially

a%%ected' The seve"ity o% the heat t"eatent and the length o% sto"age de$end on the nat!"e o% the$"od!ct) $H conditions) the "esistance o% the ta"get ic"oo"ganis o" en(ye) the sensitivity o%

the $"od!ct) and the ethod o% heating'


13/19

2ost $aste!"i(ation o$e"ations involving li+!ids il*) il* $"od!cts) #ee") %"!it 5!ices)

li+!id egg) etc; a"e ca""ied o!t in contin!o!s heat e-change"s' The $"od!ct te$e"at!"e is +!ic*ly

"aised to the $aste!"i(ation levels in the %i"st heat e-change") held %o" the "e+!i"ed length o% tiein the holding t!#e) and +!ic*ly cooled in a second heat e-change"' Fo" visco!s %l!ids) a s&e$t

s!"%ace heat e-change" is o%ten !sed to $"oote %aste" heat t"ans%e" and to $"event s!"%ace

%o!ling $"o#les' In.$ac*age $aste!"i(ation is siila" to conventional the"al $"ocessing o%%oods e-ce$t that it is ca""ied o!t at lo&e" te$e"at!"es' The the"al $"ocessing o% high acid

%oods nat!"al o" acidi%ied; is also soeties te"ed $aste!"i(ation to indicate that "elatively

ilde" heat t"eatent is involved gene"ally ca""ied o!t at #oiling &ate" te$e"at!"es;'

SE$TI! II# STE&I2I/%TI!

Ste"ili(ation i$lies the dest"!ction o% all via#le ic"oo"ganiss and is not the

a$$"o$"iate &o"d to #e !sed %o" the"al $"ocessing o% %oods) #eca!se these %oods a"e %a" %"o#eing ste"ile in the edical sense o% the &o"d' The s!ccess o% the"al $"ocessing does not lie in

dest"oying all via#le ic"oo"ganiss #!t in the %act that togethe" &ith the nat!"e o% the %ood

$H;) envi"onent vac!!;) he"etic $ac*aging) and sto"age te$e"at!"e) the given heat

$"ocess $"events the g"o&th o% ic"oo"ganiss o% s$oilage and $!#lic health conce"n' Inessence) it $"esents a the"al $"ocess in &hich %oods a"e e-$osed to a high.eno!gh te$e"at!"e

%o" a s!%%iciently long tie to "ende" the coe"cially ste"ile' The $"ocess ta*es into acco!ntthe heat "esistance o% the s$o"e %o"e"s in addition to thei" g"o&th sensitivity to o-ygen) $H) and

te$e"at!"e' The $"esence o% vac!! in cans $"events the g"o&th o% ost ae"o#ic

ic"oo"ganiss) and i% the sto"age te$e"at!"e is *e$t #elo& 49@C) the heat."esistant the"o$iles$ose little o" no $"o#le' F"o the $!#lic health $e"s$ective) the ost i$o"tant ic"oo"ganis

in lo&.acid $H M 7'9; %oods is Clostridium botulinum) a heat."esistant) s$o"e.%o"ing) anae"o#ic

$athogen that) i% it s!"vives $"ocessing) can $otentially g"o& and $"od!ce the deadly #ot!lis

to-in in %oods' 3eca!se C. botulinumand ost s$o"e %o"e"s do not g"o& at $H 7'9 acid andedi!.acid %oods;) the the"al $"ocessing c"ite"ion %o" these %oods is the dest"!ction o% heat.

"esistant yeasts and olds) vegetative ic"oo"ganiss) o" en(yes' 3eca!se s$o"e %o"e"s

gene"ally have high heat "esistance) the lo&.acid %oods that s!$$o"t thei" g"o&th a"e $"ocessed atelevated te$e"at!"es 119.149@C;) &he"eas acid %oods need only to #e #"o!ght to @.@ @C %o"

ade+!ate inactivation o% en(yes o" dest"!ction o% vegetative cells) yeasts) and olds'

QUESTI!S

1' What is the di%%e"ence #et&een ste"ili(ation and $aste!"i(ation?

4' The ain $!"$ose o% ste"ili(ation and $aste!"i(ation'6' A"e s$o"e L%o"e" ic"oo"ganiss dest"oyed in $aste!"i(ation?

7' Can $aste!"i(ed %oods #e $"ese"ved in no"al sto"age condition?

9' Does the $aste!"i(ation $"ocess a%%ect g"eatly the senso"y cha"acte"istics and n!t"itiveval!e o% the %ood?

' A"e en(yes inactivated in the $aste!"i(ation $"ocess?

' ive e-a$le o% %ood $"od!cts &hich is t"eated #y $aste!"i(ation' Desc"i#e the stages in the $aste!"i(ation $"ocess'

' What is the e+!i$ent %o" holding the $aste!"i(ation te$e"at!"e called?

1@' What does the te"


14/19

14' What ic"oo"ganis is conside"ed as the ost i$o"tant in te"s o% $!#lic health

conce"n) es$ecially in lo& acid %oods ? Why?

16' What a"e the $h val!es %o" lo&.acid and acid %oods?17' What ta"get ic"oo"ganiss a"e dest"oyed #y heat $"ocessing %o" acid %oods?

19' Why is te$e"at!"e "e+!i"eent o% the"al $"ocessing %o" acid %oods lo&e" than %o" lo&

acid %oods?

U!IT 4# T(E IS$UIT I!*UST&)

W(%T %&E IS$UITS?

3isc!its a"e sall #a*ed $"od!cts ade $"inci$ally %"o %lo!") s!ga" and %at' They

ty$ically have a oist!"e content o% less than 7J and &hen $ac*aged in oist!"e.$"oo%

containe"s have long shel% lives) $e"ha$s si- onths o" o"e' The a$$eal to cons!e"s isdete"ined #y the a$$ea"ance and eating +!alities' Fo" e-a$le) cons!e"s do not li*e #"o*en

#isc!its no" ones that have #een ove" o" !nde" #a*ed'3isc!its a"e ade in any sha$es and si(es and a%te" #a*ing they ay #e coated &ith

chocolate) sand&iched &ith a %at.#ased %illing o" have othe" $leasantly %lavo"ed additions'

(W %&E IS$UITS +%*E?

3isc!its a"e a t"aditional ty$e o% %lo!" con%ectione"y &hich &e"e) and can still #e) ade

and #a*ed in a doestic *itchen' No& they a"e ade ostly in %acto"ies on la"ge $"od!ction

$lants' These $lants a"e la"ge and co$le- and involve conside"a#le echanical so$histication'Fo"ing) #a*ing and $ac*aging a"e la"gely contin!o!s o$e"ations #!t ete"ing ing"edients and

do!gh i-ing a"e ty$ically done in #atches'

The"e is a high deg"ee o% echani(ation in the #isc!it ind!st"y #!t at $"esent the"e a"eve"y %e& co$letely a!toatic $"od!ction $lants' This eans that the"e is a high deg"ee o%

de$endence on the o$e"ato"s to sta"t and cont"ol $"od!ction $lant' It is essential that o$e"ato"s a"e

s*illed in the tas*s they have to do and this involves "es$onsi#ility %o" $"od!ct +!ality' As $a"t o%thei" t"aining they !st *no& a#o!t the ing"edients and thei" "oles in a*ing #isc!its' They !st

#e a&a"e o% the $otential ing"edient +!ality va"iations and the signi%icance o% these'

The"e a"e #asically t&o ty$es o% #isc!it do!gh) ha"d and so%t' The di%%e"ence is

dete"ined #y the ao!nt o% &ate" "e+!i"ed to a*e do!gh &hich has satis%acto"y handling+!ality %o" a*ing do!gh $ieces %o" #a*ing'

Ha"d do!gh has high &ate" and "elatively lo& %at and s!ga"; contents' The do!gh is

to!gh and e-tensi#le it can #e $!lled o!t &itho!t iediately #"ea*ing;) li*e tight #"ead do!gh'The #isc!its a"e eithe" c"ac*e"s o" in a g"o!$ *no&n as sei.s&eet o" ha"d s&eet'

So%t do!ghs contain !ch less &ate" and "elatively high levels o% %at and s!ga"' The

do!gh is sho"t) #"ea*s &hen it is $!lled o!t; &hich eans that it inhi#its ve"y lo& e-tensi#lecha"acte"' It ay #e so%t that it is $o!"a#le' The #isc!its a"e o% the so%t eating ty$es &hich a"e

o%ten "e%e""ed to as


15/19

The achine"y !sed to a*e #isc!its is designed to s!it the ty$e o% do!gh needed and to

develo$ the st"!ct!"e and sha$e o% the individ!al #isc!its'

Seconda"y $"ocessing) &hich is done a%te" the #isc!it has #een #a*ed) and $ac*aging o%#isc!its a"e s$eci%ic to the $"od!ct conce"ned' The"e is no"ally a liited "ange o% #isc!it ty$es

that can #e ade #y given set o% $lant achine"y'

2any #isc!it $"od!ction $lants #a*e at the "ate o% 1@@@.4@@@ *g $e" ho!" and highe" "atesa"e not !n!s!al' iven this and the so$histication o% the $"od!ction line it is ost econoical to

a*e only one #isc!it ty$e %o" a &hole day o" at least an eight ho!" shi%t'

QUESTI!S

1' Which ing"edients a"e #isc!its ade %"o?

4' What oist!"e do #isc!its ty$ically have?6' In te"s o% $ac*aging) ho& is the shel% li%e o% #isc!its $"olonged?

7' D!e to a high deg"ee o% echani(ation in the #isc!it ind!st"y) ho& i$o"tant is the "ole

o% the o$e"ato"s?

9' What "e+!i"eents do o$e"ato"s in #isc!it $"od!ction need to eet?

U!IT 5# F* ,&ESE&3%TI!

Food $"ese"vation is the $"ocess o% t"eating and handling %ood in s!ch a &ay as to sto$ o"

g"eatly slo& do&n s$oilage to $"event %ood#o"ne illness &hile aintaining n!t"itional val!e)

te-t!"e and %lavo"'

/"ese"vation !s!ally involves $"eventing the g"o&th o% #acte"ia) %!ngi and othe" ic"o.

o"ganiss) as &ell as "eta"ding the o-idation o% %at &hich ca!se "ancidity' It also incl!des$"ocesses to inhi#it nat!"al aging and discolo!"ation that can occ!" d!"ing %ood $"e$a"ation s!ch

as the $oly$henolo-idase "eaction in a$$les &hich ca!ses #"o&ning &hen a$$les a"e c!t' Soe

$"ese"vation ethods "e+!i"e the %ood to #e sealed a%te" t"eatent to $"event "e.containation&ith ic"o#esG othe"s) s!ch as d"ying) allo& %ood to #e sto"ed &itho!t any s$ecial containent

%o" long $e"iods'

/"ese"vation $"ocesses incl!de:

Heating to *ill o" denat!"e o"ganiss e'g' #oiling;

O-idation e'g !se o% s!l$h!" dio-ide;

To-ic inhi#ition e'g' so*ing) !se o% ca"#on dio-ide) vinega") alcohol etc; Dehyd"ation d"ying;

Osotic inhi#ition e'g !se o% sy"!$s;

8o& te$e"at!"e inactivation e'g' %"ee(ing;

2any co#inations o% these ethods

One o% the oldest ethods o% %ood $"ese"vation is #y d"ying) &hich "ed!ces &ate" activity

s!%%icient to delay o" $"event #acte"ial g"o&th' 2ost ty$es o% eat can #e d"ied and this is


16/19

es$ecially val!a#le in the case o% $ig eat since this is di%%ic!lt to *ee$ &itho!t $"ese"vation'

2any %"!its can also #e d"ied and the $"ocess is o%ten a$$lied to a$$les) $ea"s) #ananas) angoes)

$a$aya) cocon!t etc' D"ying is also the no"al eans o% $"ese"vation %o" ce"eal g"ains s!ch as&heat) ai(e) oats) #a"ley) "ice'

/"o#a#ly as old as d"ying) any A"ctic co!nities &o!ld $"ese"ve %ood in holes o"la"de"s d!g into the ice' The"e is a t"adition in Scandinavia o% $"ese"ving %ish and es$ecially

he""ings in this &ay' F"ee(ing is also one o% the ost coonly !sed $"ocesses coe"ciallyand doestically %o" $"ese"ving a ve"y &ide "ange o% %ood st!%%s incl!ding $"e$a"ed %ood st!%%s

&hich &o!ld not have "e+!i"ed %"ee(ing in thei" !n$"e$a"ed state' Fo" e-a$le) $otato &a%%les

a"e sto"ed in the %"ee(e") #!t $otatoes theselves "e+!i"e only a cool da"* $lace to ens!"e anyonths, sto"age' Cold sto"es $"ovide la"ge vol!e) long.te" sto"age %o" st"ategic %ood stoc*s

held in case o% national ee"gency in any co!nt"ies'

Canning involves coo*ing %"!its o" vegeta#les) sealing the in ste"ile cans o" 5a"s) and

#oiling the containe"s to *ill o" &ea*en any "eaining #acte"ia' a"io!s %oods have va"ying

deg"ees o% nat!"al $"otection against s$oilage and ay "e+!i"e that the %inal ste$ occ!" in a$"ess!"e coo*e"' High.acid %"!its li*e st"ae""ies "e+!i"e no $"ese"vatives to can and only a

sho"t #oiling cycle) &he"eas a"ginal %"!its s!ch as toatoes "e+!i"e longe" #oiling and additiono% othe" acidic eleents' 2any vegeta#les "e+!i"e $"ess!"e canning' Food $"ese"ved #y canning

o" #ottling is at iediate "is* o% s$oilage once the can o" #ottle has #een o$ened' 8ac* o%

+!ality cont"ol in the canning $"ocess ay allo& ing"ess o% &ate" o" ic"o.o"ganiss' 2ost s!ch%ail!"es a"e "a$idly detected as deco$osition &ithin the can ca!ses gas $"od!ction and the can

&ill s&ell o" #!"st' Ho&eve") the"e have #een e-a$les o% $oo" an!%act!"e and $oo" hygiene

allo&ing containation o% canned %ood #y the o#ligate anae"o#e) Clostridium botulinum&hich

$"od!ces an ac!te to-in &ithin the %ood leading to seve"e illness o" death' This o"ganis$"od!ces no gas o" o#vio!s taste and "eains !ndetected #y taste o" sell'

/ic*ling is a ethod o% $"ese"ving %ood #y $lacing it o" coo*ing it in a s!#stance that

inhi#its o" *ills #acte"ia and othe" ic"o.o"ganiss' This ate"ial !st also #e %it %o" h!ancons!$tion' Ty$ical $ic*ling agents incl!de #"ine high in salt;) vinega") ethanol) and vegeta#le

oil) es$ecially olive oil #!t also any othe" oils' 2ost $ic*ling $"ocesses also involve heating o"

#oiling so that the %ood #eing $"ese"ved #ecoes sat!"ated &ith the $ic*ling agent' F"e+!ently

$ic*led ites incl!de vegeta#les s!ch as ca##age) $e$$e"s) and soe anial $"od!cts s!ch asco"ned #ee% and eggs'

ac!!.$ac*ing sto"es %ood in a vac!! envi"onent) !s!ally in an ai".tight #ag o"

#ottle' The vac!! envi"onent st"i$s #acte"ia o% o-ygen needed %o" s!"vival) hence $"eventing

the %ood %"o s$oiling' ac!!.$ac*ing is coonly !sed %o" sto"ing n!ts'

2odi%ied atos$he"e is a &ay to $"ese"ve %ood o$e"ating on the atos$he"e a"o!nd it'

Salad c"o$s &hich a"e noto"io!sly di%%ic!lt to $"ese"ve a"e no& #eing $ac*aged in sealed #ags

&ith an atos$he"e odi%ied to "ed!ce the o-ygen concent"ation and inc"ease the ca"#on dio-ideconcent"ation' The"e is conce"n that altho!gh salad vegeta#les "etain thei" a$$ea"ance and te-t!"e

in s!ch conditions) this ethod o% $"ese"vation ay not "etain n!t"ients) es$ecially vitains'

"ains ay #e $"ese"ved !sing ca"#on dio-ide' A #loc* o% d"y ice is $laced in the #otto and the


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can is %illed &ith g"ain' The can is then P#!"$edP o% e-cess gas' The ca"#on dio-ide %"o the

s!#liation o% the d"y ice $"events insects) old) and o-idation %"o daaging the g"ain' "ain

sto"ed in this &ay can "eain edi#le %o" %ive yea"s'

Soe %oods) s!ch as any t"aditional cheeses) &ill *ee$ %o" a long tie &itho!t !se o%

any s$ecial $"oced!"es' The $"ese"vation occ!"s #eca!se o% the $"esence in ve"y high n!#e"s o%#ene%icial #acte"ia o" %!ngi &hich !se thei" o&n #iological de%ences to $"event othe" o"ganiss

gaining a %oot.hold'

S!ga" is !sed to $"ese"ve %"!its) eithe" in sy"!$ &ith %"!it s!ch as a$$les) $ea"s) $eaches)

a$"icots) $l!s o" in c"ystali(ed %o" &he"e the $"ese"ved ate"ial is coo*ed in s!ga" to the

$oint o% c"ystali(ation and the "es!ltant $"od!ct is then sto"ed d"y' This ethod is !sed %o" thes*ins o% cit"!s %"!it candied $eel;) angelica and ginge"' The !se o% s!ga" is o%ten co#ined &ith

alcohol %o" $"ese"vation o% l!-!"y $"od!cts s!ch as %"!it in #"andy o" othe" s$i"its'

Food ay #e $"ese"ved #y coo*ing in a ate"ial that solidi%ies to %o" a gel' S!ch

ate"ials incl!de gelatine) aga") ai(e %lo!" and a""o&"oot %lo!"' Soe %oods nat!"ally %o" a$"otein gel &hen coo*ed'

QUESTI!S#

1' What is %ood $"ese"vation?4' What is %ood#o"ne illness?

6' What do $"ese"vation $"ocesses incl!de?

7' Ho& can d"ying ethod $"ese"ve %oods?9' What is the "ole o% cold sto"es in %ood $"ese"vation?

' What is $ic*ling ethod?

' Ho& can g"ains #e $"ese"ved #y !sing odi%ied atos$he"e?..........oooOooo..........

U!IT 6# F* ,%$7%8I!8

Food $ac*aging develo$ent sta"ted &ith h!an*inds ea"liest #eginnings' Ea"ly %o"s

o% $ac*aging "anged %"o go!"ds to sea shells to anial s*in' 8ate" cae $otte"y) cloth and

&ooden containe"s' These $ac*ages &e"e c"eated to %acilitate t"ans$o"tation and t"ade'

Utili(ing ode"n technology) todays society has c"eated an ove"&heling n!#e" o%ne& $ac*ages containing a !ltit!de o% %ood $"od!cts' A ode"n %ood $ac*age has any

%!nctions) its ain $!"$ose #eing to $hysically $"otect the $"od!ct d!"ing t"ans$o"t' The $ac*age

also acts as a #a""ie" against $otential s$oilage agents) &hich va"y &ith the %ood $"od!ct' Fo"

e-a$le) il* is sensitive to lightG the"e%o"e) a $ac*age that $"ovides a light #a""ie" is necessa"y'The il* ca"ton is ideal %o" that' Othe" %oods li*e $otato chi$s a"e sensitive to ai" #eca!se the

o-ygen in the ai" ca!ses "ancidity) &hich is a condition o% s$oiled oil cha"acte"i(ed #y


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o#5ectiona#le odo" and %lavo"' The #ags containing $otato chi$s a"e ade o% ate"ials &ith

o-ygen. #a""ie" $"o$e"ties' /"actically all %oods sho!ld #e $"otected %"o %ilth) ic"oo"ganiss)

oist!"e and o#5ectiona#le odo"s' We "ely on the $ac*age to o%%e" that $"otection'

Aside %"o $"otecting the %ood) the $ac*age se"ves as a vehicle th"o!gh &hich the

an!%act!"e" can co!nicate &ith the cons!e"' N!t"itional in%o"ation ing"edients and o%ten"eci$es a"e %o!nd on a %ood la#el' The $ac*age is also !tili(ed as a a"*eting tool designed to

att"act yo!" attention at the sto"e' This a*es $"inta#ility an i$o"tant $"o$e"ty o% a $ac*age'

The %ood ind!st"y !tili(es %o!" #asic $ac*aging ate"ials: etal) $lant atte" $a$e" and

&ood;) glass and $lastic' A n!#e" o% #asic $ac*aging ate"ials a"e o%ten co#ined to give a

s!ita#le $ac*age' The %"!it d"in* #o- is an e-a$le &he"e $lastic) $a$e" and etal a"e co#inedin a lainate to give an ideal $ac*age' This conce$t can #e easily seen in yo!" $ean!t #!tte" 5a"'

The ain $ac*age containing the %ood $"ia"y $ac*age; is ade o% glass o" $lastic;) the lid is

ade o% etal lined &ith $lastic) and the la#el is ade o% $a$e"'

Each #asic $ac*aging ate"ial has advantages and disadvantages' 2etal is st"ong and agood ove"all #a""ie") #!t heavy and $"one to co""osion' /a$e" is econoical and has good

$"inting $"o$e"tiesG ho&eve") it is not st"ong and it a#so"#s &ate"' lass is t"ans$a"ent) &hich

allo&s the cons!e" to see the $"od!ct) #!t #"ea*a#le' /lastics a"e ve"satile #!t o%ten e-$ensive'

The"e%o"e) co#ining the #asic ate"ials &o"*s &ell in ost cases' So) %o" a $"od!ct li*e il*)&hich is an essential %ood %o" child"en and yo!ng ad!lts and the"e%o"e cannot #e ve"y e-$ensive)

$a$e" a*es a good econoical ate"ial' It also $"ovides a good $"inting s!"%ace' Ho&eve")

since $a$e" a#so"#s &ate") it &ill gain oist!"e %"o the il*) get &ea*e" and %ail) the"e#ye-$osing the il* to s$oilage %acto"s' It ay even #"ea* and &aste the $"od!ct' When a thin

laye" o% a $lastic called $olyethylene is !tili(ed to line the inside o% the il* ca"ton) it se"ves as a

#a""ie" to oist!"e and a*es an econoical) %!nctional $ac*age'

A%te" a*ing a %ood $"od!ct and $lacing it in the a$$"o$"iate $ac*age) a n!#e" o% theseindivid!al $ac*ages !st #e $laced in a la"ge containe" to %acilitate shi$ent' These la"ge"

containe"s a"e called seconda"y $ac*ages' The $a$e"#oa"d #o- is a ve"y coon seconda"y

$ac*age' /lastics also can se"ve as seconda"y $ac*ages' The il* case in &hich a n!#e" o% il*ca"tons a"e delive"ed to the s!$e"a"*et is a good e-a$le'

We cannot disc!ss %ood $ac*aging &itho!t disc!ssing the e%%ects o% $ac*aging &aste on

the envi"onent' Clea"ly) "ecycling is a so!nd a$$"oach' Ho&eve") the $"o#le o%ten lies in

%easi#ility o% collection) se$a"ation and $!"i%ication o% the cons!e"s dis$osed %ood $ac*ages'This ode o% "ecycling is called $ost.cons!e" "ecycling' While it o%%e"s a logistic challenge)

"ecycling is gaining in $o$!la"ity) and the $ac*aging ind!st"y is coo$e"ating in that e%%o"t'

Al!in! cans a"e the ost "ecycled containe" at this tie' /lastic "ecycling is inc"easing) yetost $lastic is "ecycled d!"ing an!%act!"ing o% the containe"sG not as $ost.cons!e" "ecycling'

Fo" e-a$le) t"iings %"o $lastic #ottles a"e "eg"o!nd and "e$"ocessed into ne& ones'

The $lastics ind!st"y is hel$ing to %acilitate cons!e" "ecycling #y identi%ying the ty$e o%

$lastic %"o &hich the containe" is ade' A n!#e" %"o 1 to is $laced &ithin the "ecyclinglogo on the containe"s #otto' Fo" e-a$le) 1 "e%e"s to /ET /olyethylene Te"e$hthalate;) the


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$lastic !sed %o" the la"ge 4 lite" so%t d"in* #ottles' /lastics have the advantage o% #eing light' This

hel$s to conse"ve %!el d!"ing t"ans$o"t and also "ed!ces the ao!nt o% $ac*age &aste'

The"e a"e any inte"esting $ac*aging conce$ts #eing e-$lo"ed #y the ind!st"y to *ee$ !$&ith the changing li%e style o% the cons!e" and ne& technologies' 2any $"o%essionals a"e

involved in designing and an!%act!"ing the ode"n $ac*age' Today,s $ac*age is designed &iththe cons!e",s sa%ety and convenience in ind' E-a$les a"e ic"o&avea#le $o$co"n $ac*ages)

s+!ee(a#le *etch!$ #ottles and the ta$e".$"oo% il* #ottle ca$'

QUESTI!S

1' In te" o% $ac*aging) &hat does #a""ie" ean?

4' What does /"ia"y /ac*age ean?

6' What does Seconda"y /ac*age ean?

7' What dose /"inta#ility ean?

9' E-$lain a#o!t "ancidity

' What is /ET a##"eviated %o"?

' What is /E a##"eviated %o"?

' What does lainated $ac*age ean?

' What a"e the th"ee #asic $ac*aging ate"ials that a*e !$ the %"!it d"in* #o-?

1@' Which $lastic is !tili(ed to line the inside o% the il* ca"ton?

..........oooOooo..........

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