ppt for lpt 321.pptx

8/18/2019 PPT for LPT 321.pptx

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LECTURE NOTES FOR THE UNDERGRADUATECOURSE (2013-2014 Batch)

LPT – 321 MEAT SC ENCE (1!1)

D"# $# DUSH%ANTHAN& M#'#Sc#& Ph#D#&PROFESSOR

DEPARTMENT OF L 'ESTOC$ PRODUCTS TECHNOLOG% (MEAT SC ENCE)&

MADRAS 'ETER NAR% COLLEGE&

CHENNA – 00 00201


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201


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STRUCTURE AND COMPOSITION OF MUSCLE

Meat - composed primarily - muscle associated co!!ecti"e tissues li#eadipose tissue $%at& 'o!e a!d cartila(e as )ell as epit*elial a!d !er"oustissues a!d co!!ecti"e tissue proper+S#eletal muscle - pri!cipal source o% muscle tissues i! meat+ Small amou!to% smoot* mMuscle - also prese!t i! meat+

T*e muscle , co!!ecti"e tissues to t*e .ualitati"e a!d .ua!titati"ec*aracteristics o% meat+Meat is !ot sy!o!ymous )it* muscle e"e! t*ou(* it is made mostly o%muscle+T*e skeletal muscles co!stitute - a'out /0-102 o% t*e carcass )ei(*t o% meata!imals+I! additio! - co!sists o% some smooth muscle primarily - compo!e!t o% 'lood"essels+Cardiac muscle - co!%i!ed solely to t*e *eart+

T*ese muscles co!stitute a'out /3-402 o% t*e li"e )ei(*t or /0-132 o% t*ecarcass )ei(*t o% meat a!imals+


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MUSCLE FI9RE• T*e structural u!it o% s#eletal muscle tissue - muscle

fibre. • :i(*ly speciali6ed cell• Muscle %i'res co!stitute ;0-or "olume - remai!i!( "olumes- e8tracellular %luid+

• Muscle %i'res - lo!( u!'ra!c*ed t*readli#e cells )*ic*taper sli(*tly at 'ot* e!ds+

• ?ary co!sidera'ly i! diameter ra!(i!( %rom @3 µm tomore t*a! @33 µm $@ µm micrometer o!e millio!t*o% a meter& )it*i! t*e same species a!d e"e! )it*i! t*esame muscle+


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NUCLEIS#eletal muscle %i'res - multi!ucleated due to

treme!dous "ariatio! i! t*eir le!(t* - !um'er o% !ucleiper %i're is !ot co!sta!t+A %i're se"eral ce!timeters lo!( - se"eral *u!dred !uclei- re(ular distri'utio! e"ery 0 µm alo!( its le!(t*e8cept !ear te!di!ous attac*me!ts )*ere t*ey i!creasei! !um'er a!d are more irre(ularly distri'uted+T*e !um'er o% !uclei - i!creases - "ici!ity - myo!eural

>u!ctio!+I! mammalia! muscle !uclei - located - perip*ery -%i're >ust 'e!eat* - sarcolemma+Ellipsoidal i! s*ape - lo!(est a8is orie!ted parallel to t*elo!( a8is o% t*e %i're .


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M OFI9RILSA! or(a!elle u!i.ue to muscle tissue+Lo!( t*i! cyli!drical rods @ to < µm i! diameter+

9at*ed 'y t*e sarcoplasm - e8te!d t*e e!tire le!(t* - muscle %i're+Muscle %i're - 03 µm diameter -%rom @333 - =333 $more& myo%i'rils+Cross-sectio!s - myo%i'rils )ell-ordered array o% dots - t)odisti!ct si6es - myofilaments $)it*i! t*e myo%i'rils&+

T*e myo%ilame!ts - thick a!d thin filaments - myo%i'ril+lo!(itudi!al sectio! - t*ic# %ilame!ts - ali(!ed parallel to eac*ot*er - arra!(ed i! e8act ali(!me!t across t*e e!tire myo%i'ril+T*i! %ilame!ts - ali(!ed across - myo%i'ril - parallel - eac* ot*er -t*ic# %ilame!ts+Arra!(eme!t 7 t*ic# %ilame!ts o"erlappi!( - certai! re(io!s alo!(- lo!(itudi!al a8es - accou!ts - c*aracteristic 'a!di!( - striatedappeara!ce - myo%i'ril+T*is 'a!di!( e%%ect - ta#es %orm - alter!ati"e li(*t a!d dar# areas

- term striated muscle i! re%ere!ce to s#eletal muscle+


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it*i! li(*t a!d dar# 'a!ds o% t*e myo%i'rils - areas - di%%ere!t de!sityLi(*t 'a!d - si!(ly re%racti"e "ie)ed - polari6ed li(*t - descri'ed as -isotropic - called t*e I band9road dar# 'a!d - dou'ly re%racti"e - or a!isotropic- i! polari6ed li(*t -

desi(!ated t*e ! band +A 'a!d - muc* de!ser t*a! - GIH 'a!d+9ot* t*e A a!d I 'a!ds - 'isected 'y - t*i! li!es+GIH 'a!d - 'isected - dar# t*i! 'a!d - li!e +T*e u!it - myo%i'ril 'et)ee! t)o ad>ace!t li!es - a S!"C#$%"%.

Sarcomere i!cludes 'ot* a! A 'a!d a!d t*e t)o *al% I 'a!ds located o!eit*er side - A 'a!d+Sarcomere - repeati!( structural u!it o% t*e myo%i'ril - 'asic u!it e"e!ts -muscleHs co!tractio!-rela8atio! cycle occur+

Sarcomere len&th - !ot co!sta!t dime!sio!s 7 GIH 'a!d - aredepe!de!t o! t*e state o% co!tractio! - time t*e muscle is e8ami!ed+I! - ce!tral re(io! - A 'a!d - area - sli(*tly less de!sity t*a! -remai!der 'a!d - li(*ter re(io! - called - ' (one .Narro) de!se 'a!d - $ li!e - 'isects - ce!ter - A 'a!d+A re(io! - lo) de!sity appears )it*i! - : 6o!e o! eit*er side - M li!e -

pseudo ' (one +


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M OFILAMENTS


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M OFILAMENTST*ic# 7 t*i! 'a!ds di%%er i! t*eir dime!sio!s - c*emical compositio! - properties 7positio! )it*i! t*e sarcomere+T*ic# %ilame!ts - @4-@1 !m $!a!ometers& i! diameter 7 @+0 µm lo!( - co!stitute t*e A

'a!d sarcomere co!sist myosin - re%erred to - myosin filaments. :eld i! tra!s"erse a!dlo!(itudi!al re(ister 'y t*i! cross 'a!ds located periodically alo!( t*e le!(t* a!d 'y crossco!!ectio!s i! t*e ce!tre o% t*e A 'a!d+ T*e ali(!me!t o% t*ese cross co!!ectio!s i! t*e ce!tre o% t*e A 'a!d correspo!ds to t*etra!s"erse de!sity c*aracteristics o% t*e M-li!e+

T*i! %ilame!ts - 1- !m i! diameter - e8te!d appro8imately @+3 µm o! eit*er side - li!e -co!stitute GIH 'a!d sarcomere - co!sist primarily - actin - re%erred to - actin filaments. ' (one - less de!se t*a! - rest - A 'a!d - ce!tre re(io! 'et)ee! t*e e!ds o% t*e opposi!(acti! %ilame!ts+

idt* - ' (one "aries - state o% co!tractio! - muscle+De!sest area - A 'a!d - o! t*e eit*er side - ' (one - 'ot* t*e acti! a!d myosi! %ilame!ts -prese!t+)I* band co!tai!s o!ly - t*i! acti! %ilame!ts - least de!se 'a!d o% t*e e!tire myo%i'ril+Myosi! %ilame!ts - ' (one re(io! - sarcomere - orie!ted - de%i!ite *e8a(o!al patter! si8t*i! %ilame!ts surrou!d eac* t*ic# %ilame!t+


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LINE ULTRASTRUCTURE


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- LINE ULTRASTRUCTURELo!(itudi!al sectio! - acti! %ilame!t o! o!e side - + line lies 'et)ee!t)o acti! %ilame!ts - opposite side - + line.

I!dicati!( - acti! %ilame!ts per se do !ot pass t*rou(* - li!e +Acti! %ilame!ts - 'elie"ed - termi!ate at - li!e+ Ultra-t*i! %ilame!ts - + filaments - co!stitute - material - li!e 7t*ey co!!ect - acti! %ilame!ts o! eit*er side o% it+

Near - li!e - eac* acti! %ilame!t co!!ects to %our %ilame!ts t*atpass o'li.uely t*rou(* - li!e+Eac* - 4 %ilame!ts - co!!ects - acti! %ilame!t - ad>ace!t sarcomere+Structural arra!(eme!t - li!e - eac* acti! %ilame!t - o!e sarcomere

orie!ted - ce!tre - %our acti! %ilame!ts - !e8t sarcomere+Lo!(itudi!al sectio!s - o%%set $or o'li.ue& arra!(eme!t - %ilame!ts results - c*aracteristic 6i(6a( patter! - li!e 7 e8plai!s )*y a!acti! %ilame!t o! side - li!e appears - lie 'et)ee! t)o acti!%ilame!ts o! eit*er side o% it+

PROTEINS OF T E M OFILAMENTS


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PROTEINS OF T:E M OFILAMENTSProtei!s acti! a!d myosi! co!stitute ;0- 32 -myo%i'ril 7 remai!i!( - re&ulatory proteins. So !amed - direct or i!direct re(ulatory %u!ctio!s -ade!osi!e trip*osp*ate-acti!-myosi! comple8+Ot*er re(ulatory protei!s - tropomyosi! tropo!i! t)o

M protei!s J-acti!i! C protei! a!d K-acti!i! listed -decreasi!( order o% co!ce!tratio! - myo%i'ril+Protei!s - t*ic# a!d t*i! %ilame!ts - re(ulatory protei!sare re%erred to as myofibrillar proteins.

T*e re(ulatory protei!s - associated - "arious eleme!ts- myo%i'ril+ Tropomyosi! "irtue - imi!o (roupco!tri'utes - %oldi!( amo!( polypeptide c*ai!s t*atresults i! t*e %ormatio! o% a (lo'ular $sp*erical& s*apedmolecule appro8imately 0+0 !m i! diameter+

Blo'ular molecule re%erred actin $(lo'ular acti! & a!d


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Blo ular molecule re%erred - -actin $(lo ular acti! & a!das suc* co!stitutes t*e mo!omeric $si!(le molecule& %ormo% acti!+

T*e %i'rous !ature o% t*e acti! %ilame!t occurs 'ecause o%t*e lo!(itudi!al polymeri6atio! $li!#i!(& o% B-acti!mo!omers to %orm -actin $%i'rous acti! &+I! F-acti! t*e B-acti! mo!omers are li!#ed to(et*er i!

stra!ds muc* li#e t*e 'eads o! a stri!( o% pearls+T)o stra!ds o% F-acti! are spirally coiled arou!d o!ea!ot*er to %orm a super *eli8 t*at is c*aracteristic o%t*e acti! %ilame!t+

From t*is *elical arra!(eme!t o% B-acti! mo!omers t*eacti! %ilame!tHs o"erall diameter o% appro8imately 1- !mca! 'e readily "isuali6ed+T*e isoelectric p' $p: o% mi!imum electrical c*a!(e a!d

solu'ility& o% acti! is appro8imately 4+;+

Myosi! - 03-002 - myo%i'rillar protei! 7 c*aracteri6ed - *i(*


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Myosi! 03 002 myo%i rillar protei! 7 c aracteri6ed i(proportio! - 'asic 7 acidic ami!o acids ma#i!( - *i(*ly c*ar(edmolecule+Acti! - possesses a relati"ely lo) c*ar(e+ T*e isoelectric p: o%

myosi! is appro8imately 0+4+ Myosi! )it* lo)er proli!e co!te!tt*a! acti! *as a more %i'rous !ature+Structure - myosi! molecule - elo!(ated rod s*ape - t*ic#e!edportio! at o!e e!d+

T*ic#e!ed e!d - myosi! molecule - usually re%erred - head re&ion 7 lo!( rod-li#e portio! - 'ac#'o!e - t*ic# %ilame!t - tail re&ion. Portio! - molecule 'et)ee! - *ead 7 tail re(io!s are called t*eneck.:ead re(io! - molecule is dou'le *eaded 7 pro>ects laterally%rom t*e lo!( a8is - %ilame!t+Myosi! is su'>ected to t*e proteolytic $protei! 'rea#do)!& actio!o% t*e e!6yme trypsi! it is split !ear t*e !ec# i!to t)o %ractio!st*at di%%er i! molecular )ei(*t li&ht meromyosin a!d heavy

meromyosi!+


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I! ce!tre - ! band - eit*er side - $ line - myosi! %ilame!t co!tai!s -


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ytail portio! - myosi! molecules )it*out - (lo'ular *eads+T*is re(io! )it*i! ' (one - eit*er side - M li!e - pseudo ' (one. Polarity - myosi! %ilame!ts - suc* t*at *eads o! eit*er side - 'are

ce!tral re(io! - ! band - orie!ted - o'li.ue a!(le a)ay - $ line. Protrudi!( *eads - %u!ctio!ally acti"e sites - t*ic# %ilame!ts - muscleco!tractio! - myosi! *eads %orm cross 'rid(es - acti! %ilame!ts+Duri!( muscle co!tractio!s eac* myosi! *ead attac*es - B-acti!molecule - acti! %ilame!t+Formatio! - cross 'rid(es 'et)ee! t*rou(* - i!teractio! - acti! 7myosi! %ilame!ts produces - c*emical comple8 - actomyosin. Formatio! - actomyosi! results - ri(id 7 relati"ely i!e8te!si'leco!ditio! - muscle+

Actomyosi! - ma>or %orm - myo%i'rillar protei!s - %ou!d - pm muscle7 ri(idity - %ollo)i!( deat* $ri(or mortis& lar(ely due - comple8+Tra!sie!t compou!d - li"i!( a!imal si!ce cross 'rid(es 'et)ee!acti! 7 myosi! %ilame!ts - 'ro#e! duri!( - rela8atio! p*ase -co!tractio! cycle+ $Cross 'rid(es - !o!e8iste!t i! muscle )*e! it is atrest+&


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BOLBI COMPLE


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Bol(i comple8 - located - sarcoplasm !ear !uclei - co!sist - %latte!ed "esicles -appare!tly %u!ctio! - co!ce!trati!( 7 pac#a(i!( apparatus - products -meta'olic productio! li!e - cell+Muscle %i're multi!ucleated - !umerous Bol(i comple8es+

?esicles - (ol(i comple8 resem'le - mem'ra!es - sarcoplasmic reticulum+SMOOT: MUSCLE

Prese!t - (reatest .ua!tity - )alls - arteries lymp* "essels 7 (astroi!testi!al 7reproducti"e tracts - i!"olu!tary !ature - lo!( u!e"e!ly t*ic#e!ed - ce!tre 7taperi!( - 'ot* - sides+Myo%i'rils - *omo(e!ous 7 do !ot s*o) alter!ati!( dar# 7 li(*t 'a!ds li#e s#eletalmuscle+No or M-li!es - SR - !ot muc* de"eloped+ Smoot* muscle - poorly - 'lood

CARDIAC MUSCLEPossesses - u!i.ue property - r*yt*mic co!tractility - co!ti!ues - early em'ryo!icli%e u!til deat*+ Resem'le c*aracteristic properties - 'ot* s#eletal a!d smoot*

muscle - also i!"olu!tary+Fi'res - rou!ded to irre(ular - s*ape 7 (i"e o%% 'ra!c*es - mi8ed up - !ear'y %i'res+Nucleus - placed - ce!tre - %i're+ Myo%i'rils depict striatio!s similar to s#eletalmuscle+Sarcoplasm s*o)s !umerous 7 more mitoc*o!dria t*a! - s#eletal or smoot*muscle+I!tercalated discs are prese!t at t*e positio! o% -li!es+

CON?ERSION OF MUSCLE TO MEAT


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CON?ERSION OF MUSCLE TO MEATCo!"ersio! o% $uscle to $eat - result - series - 'ioc*emical 'iop*ysicalc*a!(es i!itiated - muscle - deat* - a!imal due - stoppa(e - 'loodcirculatio!+Immediate c*a!(e - 'leedi!( - co!sumptio! - o8y(e! supply - muscleresulti!( - i!*i'itio! - cytoc*rome system 7 o8idati"e p*osp*orylatio!+Sarcoplasmic ATP depletes t*e ATP le"els - i!crease t*e i!or(a!icp*osp*ate - stimulates - 'rea#do)! - (lyco(e! to lactic acid+I!e%%ectual resy!t*esis - ATP 'y a!aero'ic (lycolysis ca!!ot mai!tai! - ATPle"el a!d drops - actomyosi! %orms 7 i!e8te!si'ility - ri(or mortis e!sue+Loss - e8te!si'ility re%lecti!( actomyosi! %ormatio! proceeds slo)ly at %irst$t*e delay period& t*e! - (reat rapidity $t*e %ast p*ase& e8te!si'ilityremai!s co!sta!t - lo) le"els+T*e time - o!set - ri(or - (i"e! temperature depe!ds most directly - le"el -ATP+Sy!t*esis o% ATP %rom creati!e p*osp*ate 7 ADP or 'y (lycolysis ca!!otmai!tai! - ATP le"el - too lo!(+:i(*er (lyco(e! co!te!t - muscle ca! prolo!( - time - some e8te!t - !oti!de%i!itely+

Ri(or Mortis


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(T*e %irst a!d most co!sidera'le post-mortem c*a!(e )*ic* occurs i!muscle is "i&or mortis - C*aracterised

'y *arde!i!( 7 co!tractio! - "olu!tary muscles

'y a loss i! tra!spare!cy - sur%ace - muscle causi!( dull!ess a!d'y sti%%e!i!( o% t*e >oi!ts+

It is %ollo)ed - sli(*t i!crease - temperature - carcass to @+0 C ormore a'o"e !ormal - 'ee% carcasses 7 temperature (radually drops -surrou!di!( atmosp*ere+O!set - ri(or - accompa!ied - lo)eri!( - )ater *oldi!( capacityDue to drop i! p: 7 co!se.ue!t approac* - muscle protei!s - t*eirisoelectric poi!t or due - de!aturatio! o% sarcoplasmic protei!sE"e! )*e! ri(or mortis occurred at *i(* p: - loss - )ater *oldi!(

due - disappeara!ce - ATP 7 co!se.ue!t %ormatio! - actomyosi!+Additio! - ATP - post-mortem muscle - Marc* 9e!dal %actor - stilloperati!( restores - :C to)ards - in vitro le"el+O!ce ri(or - complete t*e muscle remai!s placid 7 i!e8te!si'lepro"ided - #ept %ree %rom - co!tami!atio! - !o resolutio! - ri(or+

Contd…


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T*e lo)ered ATP le"els - di%%icult - mai!tai! - structural i!te(rity - protei!s+T*e lo)eri!( p: - accumulatio! - lactic acid also ma#es lia'le - de!ature+De!aturatio! - %re.ue!tly accompa!ied - loss o% po)er - 'i!d )ater 7 %all - p:causes - myo%i'rillar protei!s approac* - isoelectric poi!t+ 9ot* - causee8udatio!+De!aturatio! - sarcoplasmic protei!s - ma#es - lia'le - attac# cat*epsi! -E!6ymes - capa'le - 'rea#i!( do)! e"e! colla(e!ous co!!ecti"e tissue - muscle7 cause te!derisatio! - meat duri!( a(i!(+T*e 'rea#do)! protei!s - peptide 7 ami!o acids 7 accumulatio! - "arious

meta'olites %rom (lycolytic 7 ot*er processes a%%ord - ric* medium - 'acteria+A'se!ce - micro'ial spoila(e - t*e *oldi!( - u!processed meat a'o"e t*e%ree6i!( poi!t @+0 C is #!o)! as )Conditionin& !&ein&, "ipenin& a!d orTenderi(ation* - lo!( 'ee! associated - a! i!crease - te!der!ess 7 %la"our+Accumulatio! - lactic acid 7 lo)er le"el - muscle p: - importa!t postmortem

c*a!(e - co!"ersio! - muscle - meat+Rate 7 e8te!t - p: decli!e "aria'le - i!%lue!ced - species - %ood a!imal"arious pre-slau(*ter %actors e!"iro!me!tal temperature etc+Bradual decli!e co!ti!ues - appro8imately p: ; - li"i!( muscle duri!( %irst%e) *ours $0-1 *ours& 7 t*ere - little drop - !e8t @0-=3 *ours - ultimate p: -ra!(e o% 0+0 0+;+

Rate o% p: decli!e - e!*a!ced - *i(* e!"iro!me!tal temperature+ Lo)


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ultimate p: - desired - c*ec# - proli%erati!( microor(a!isms - stora(e+S*arp decli!e - postmortem p: - 'e%ore - dissipatio! - 'ody *eat t*rou(*carcass c*illi!( - cause de!aturatio! o% muscle protei!s - Muscles depictpale so%t a!d e8udate $PSE& co!ditio!+Co!trary - muscles - mai!tai! a co!siste!tly *i(* p: duri!( postmortemco!"ersio! - meat depict a dar# %irm a!d dry $DFD& co!ditio! - 9ot* t*eco!ditio!s are u!desira'le+Pre-ri(or meat - .uite te!der - its tou(*!ess i!creases u!til ri(or mortis

completed - co!ti!ues - tou(* - some more time+Resolutio! - ri(or due de!aturatio! de(radatio! - a(i!( meat - te!der+Duri!( co!"ersio! to meat - muscle - suscepti'le - i!"adi!(microor(a!isms - 'ody de%e!ce mec*a!ism stops operati!( 7 mem'ra!eproperties altered - Rapid decli!e - muscle p: - causes de!aturatio! -

colla(e!ous co!!ecti"e tissue+O!ly a%ter t*e 'ioc*emical c*a!(es - ta#es place muscle co!"erted tomeat+ T*at meat is te!der a!d %it %or co!sumptio!+Esse!tial to allo) t*e process o% Conditionin&, !&ein&, ripenin& ortenderisation u!processed meat #ept a'o"e t*e %ree6i!( poi!t $-@+0 C& i!

t*e a'se!ce o% micro'ial spoila(e+

POSTMORTEM CHANGES


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• S*a+,ht " ./ /.. a a* - S " ./ 5h6 ca* a ch ca* cha , -7 "a* h.+" ." 7 a6

• R +*t , th c. 7 " . ./ + c* t. at• at *. ./ .86, +55*6 - + c* + t. 8 a ,+ at .

(9* ,)• St." .86, 6.,*.9 5* t - h 9 t . - a ".9 c 5ath:a6 -

c t"at c6c* - c6t.ch". 6 t #• St." - c" at 5h. 5hat (CP) + - " 5h. 5h."6*at . - ADP t. ATP

(c" at 5h. 5hat ! ADP ; ATP ! c" at ) - .. 8ha+ t #

• E ",6 ta9.* - h /t - a a ".9 c 5ath:a6 " +*t , - 9" a< .: -,*6c., - *act c ac #• Th - c. t + t ** a** - ,*6c., t." - + c* - 8ha+ t #• R 6 th - ATP - a a ".9 c 5ath:a6 - .t .+,h - a ta - " =+ "

ATP * 7 * > - 5* t - /." at . - act. 6. " +*t , - . t - " ,."."t #

• 5."ta t cha , - ta< 5*ac +" , 5. t ."t 5 " . a"L. ./ H. . taP. t ."t ,*6c.*6 a 5H c*R ,." M."tL. ./ P".t ct . /". 7a , M c"..",aD ,"a at . + t. P".t .*6t c E ?6L. ./ St"+ct+"a* t ," t6

L. ./ H. . ta


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o H. . ta cha – 6 t - 5h6 .*., ca**6 9a*a ct " a* 7 ". t - h *5 - 9. 6 - c.5 +5 - t" - .86,/ c c6& 8t" 7a" at . t 5 "at+" & ",6 +55*6& tc#&

*. to H. . ta - c. t".** - "7.+ 6 t - c a - 4- +t

a/t " 9* ,#o a9 c - 9*.. +55*6 - *. - 9. 6 h at a t 5 "at+" ta"t

c* ,#

P. t ."t ,*6c.*6 a 5H c*• A9 c - .86, & a a ".9 c ,*6c.*6 * a - /." at . - *act cac - ,*6c., " "7 @

• Acc+ +*at . - *act c ac *.: " .: - + c* 5H - 5."ta t5. t ."t cha , - c. 7 " . - + c* - at#

• Rat > 8t t - 5H c* – 7a" a9* - /*+ c - 5 c - /..

a a* – 5" - *a+,ht " /act." & 7 ". ta* t 5 "at+" & tc#

. t 5 c - ,"a +a* c* c. t + - 5H -


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* 7 , + c* - / " t / : h.+" ( - h.+" ) > - * tt*".5 - 8t 1 -20 h.+" – , 7 , - +*t at 5H -

"a , - # – # #Rat - 5H c* - ha c - h ,h 7 ". ta*t 5 "at+" #L.: +*t at 5H - " - ch c< - 5".* / "at ,

c"..",a +" , t."a, #Sha"5 c* - 5. t ."t 5H - 9 /." -5at . - 9. 6 h at th".+,h ca"ca ch ** , -

ca+ at+"at . - + c* 5".t #

M+ c* 5 ct 5a* & ./t a 8+ at (PSE) c. #C. t"a"6 - + c* - a ta - c. t t*6 h ,h 5H+" , 5. t ."t c. 7 " . t. at 5 ct -a"


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R " M "t


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R ,. M. tC. t"act . - + c* a/t " ath - a .th " 5."ta t5. t ."t cha , - 5".c - c. 7 " . - + c* - at#' "6 : **-< .: - 5a"t c+*a" * 7 * ." c. c t"at . - ATPc. 5* 8 - M, !! - " =+ " - 9" a< , - act. 6. 9. >9" , , - + c* - " *a8 tat > a – ".5 5 " a tact. 6. c". 9" , 9 , - /." > + c* ,"a +a**69 c. * > * 8t 9* + " - 8t " a**6 a55*

/."c #P " . at *6 /.**.: , 8 a ,+ at . - act. 6./." at . 5".c 7 "6 *.:*6 - / " t > + c* - " *at 7 *6

8t 9* > *a t c - 5 " . - *a6 5ha - " ,." ."t #Act. 6. /." at . 5 c< +5 > + c* 9 , - *..

8t 9 * t6 - 5ha - /a t ." . t 5ha - " ,." ."t #A** - c" at 5h. 5hat (CP) – 5* t - ADP - . *. , " -5h. 5h."6*at – ATP - + c* 9 c. =+ t 8t 9* >

t //#

Sta, a"< - c. 5* t . - " ,." ."t - "a5 #


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Normal meat

PSE m eat DFD meat

P. t ."t 5H c* - 7 "6 *.: ." 7 "6 /a t - . t >


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c. 5* t . - " ,." ."t - "a5 #O t - " ,." ."t - ha c - a 9 t t 5 "at+"a9.7 20 C#

Ph . . - " ,." ."t " 9* - + c* c. t"act .- * 7 , a a* + c* 8c 5t - " ,." ."t - "" 7 " 9*+ " ." a* c. t . #R .*+t . - " ,." ."t ta< 5*ac + - c".9 a*

,"a at . - + c* t"+ct+" - + c.+" - t #P" -" ,." at - =+ t t " - t.+,h < 5 -c" a , + t * " ,." ."t - c. 5* t #

C. t + - t.+,h - . ." t - " .*+t . - " ,." +- at+"at . ." ,"a at . ." a, , - at a,a9 c. t "#O t - " ,." ."t - acc. 5a - c" a - :at "h.* , ca5ac t6#T"+ 7 :h " ,." ."t ta< 5*ac - h ,h 5H + -

a55 a"a c - ATP > c. =+ t /." at . - act. 6.

L. ./ P".t ct . /". 7a , M c"..",a


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D+" , 5. t ."t 5 " . - 9. 6 / c cha t.5 .5 "at ,> 9"a 5".5 "t - a*t " #D+" , c. 7 " . – at - + c* - =+ t + c 5t 9* - 7a ,

c"..",aE8c 5t - *.: 5H - . t - .th " 5 cha , /a7.+" 9act " a* ,".:th#Ha * , 5" ca+t . - c a"6 - 5" 7 t c. ta at . - at#

D ,"a at . + t. P".t .*6t c E ?6S 7 "a* a+t.*6t c *6 . . a* ?6 ca** cath 5 - " a

act 7 - * 7 , + c* t + - act 7at - + c* 5H c* #E ?6 t at - ,"a at . - + c* 5".t t"+ct+" #Cath 5t c ?6 - ca5a9* - 9" a< , .: - c.**a, .+ c. ct 7t + + c* > ca+ t " at . - at +" , a, ,

L. ./ St"+ct+"a* t ," t6P. t ."t a*t "at . - 9"a 5".5 "t t at - ,"a at . -

+ c+*a" 5".t #P".," 7 "+5t . - 6./ 9" **a" t"+ct+"R .*+t . - " ,." ."t - < .: - .cc+" + - t ,"at . - -*

t"+ct+" #Ra5 c* - + c* 5H - at+"at . - c.**a, .+ c. ct 7

t +

NUTRITI?E ?ALUE OF MEAT


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Meat - !utritious %ood - %ully di(esti'le - appeali!( - eyes 7 pleasi!( - se!se ol%actio!Attri'uted - its a'u!da!t *i(* .uality protei!s esse!tial %atty acids $EFA&importa!t mi!erals 7 9-comple8 (roup o% "itami!s+

Meat Protei!sMeat co!c+ source - protei!s - %ar superior - pla!t protei!s - "ery *i(* 9iol+ ?alue+Lea! meat cuts - @1+0-=32 protei!s - ric* - esse!tial ami!o acids $EAA& !otsy!t*esis - 'ody 7 de%icie!t diet )ill lead - protei! mal!utritio!Myo%i'rillar 7 sarcoplasmic protei!s - "ery *i(* .uality co!tai! EAA+

Co!!ecti"e tissue protei!s - lo)er le"els - tryptop*a! 7 sulp*ur co!tai!i!( ami!oacids+ Colla(e! - esse!tially poor - lysi!e co!te!t .Meat Fats• Co!tai! ample amou!t EFA 7 !utritio!al dema!d - 'ody easily met i m %at• Caloric "alue - %at - meat - attri'uted - %atty acids - tri(lycerides+ Num'er - calories

- lea! meat - less t*a! - deri"ed - e.ual )ei(*ts - ma!y ot*er %oods+• Caloric "alue - particular meat depe!ds - amou!t - %at - meat cuts+ Importa!t FA -

meat %at - oleic acid $u!saturated FA& %ollo)ed - palmitic a!d stearic acids$saturated FA&+

• EFA i! *uma! diets - li!oleic li!ole!ic a!d arac*ido!ic acids+• Por# 7 or(a! meats - (ood sources o% li!oleic 7 li!ole!ic acids+ E8cess dietary

li!oleic acid is co!"erted to arac*ido!ic acid i! *uma! 'ody to meet its dema!d.

P*osp*olipids - compo!e!ts - cell )all 7 mitoc*o!dria 7 play "ital role - cellularmeta'olism Meat %at co!tai!s some ua!tity o% c*olesterol a!d 'lood c*olesterol le"el


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meta olism Meat %at - co!tai!s some .ua!tity o% c*olesterol a!d lood c*olesterol le eli!creases a%ter i!(estio! o% c*olesterol i! %ood+ ell #!o)! t*at our 'ody is capa'le o%sy!t*esi6i!( more c*olesterol t*a! is !ormally i!(ested+ Or(a! meats - remar#a'le *i(*c*olesterol co!te!t as compared to s#eletal meat+

Mi!eralsMeat - (ood source - all mi!erals e8cept calcium - i! close associatio! - lea! tissues i! meatPotassium - most a'u!da!t %ollo)ed 'y p*osp*orus+ Meat - (ood source o% iro! - re.uired -sy!t*esis *aemo(lo'i! myo(lo'i! 7 certai! e!6ymes - plays "ital role mai!tai!i!( (ood*ealt*+ :uma! 'ody - limited capacity to store iro! mai!ly - li"er - a part o% re(ular dietaryi!ta#e+ Meat pro"ides t*is importa!t mi!eral i! a %orm t*at is easily a'sor'ed i! t*e

system+?itami!sLea! meat - e8celle!t source - 9-comple8 (roup - "itami!s - o!ly traces %at-solu'le "itami!s- restricted - 'ody %at+ ?itami! C - a'se!t - lea! meat - certai! or(a!s co!tai! it - mi!or.ua!tities+ Amo!( - 9-comple8 (roup o% "itami!s t*iami!e ri'o%la"i! 7 !iaci!co!ce!tratio!s - .uite *i(*

Por# surpasses se"eral meats - 9-comple8 "itami!s are co!cer!ed - lea! por# *as 0-@3 timesmote t*iami!e t*a! ot*er meats+ Mo!o(astric a!imals - pi(s i!ta#e o% "itami!s i! %eed isdirectly re%lected i! t*eir tissues+Se"eral or(a! meats - less protei! 7 %at - s#eletal meats - more eco!omical sources o%protei! 7 "itami!s t*a! retail cuts o% s#eletal meats Li"er - ric* source iro! ri'o%la"i!!iaci! 7 "itami!Nutriti"e "alue s#eletal 7 or(a! meats - properly utilised to alle"iate t*e mal!utritio!+


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FRAUDULENT SUBST TUT ON OF MEAT AND TS


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RECOGN T ON

The differentiation of the muscle and fat of animals is ofimportance in connection with the possible substitution ofinferior and at times repugnant meat for that of good quality.The substitutions – practiced - horseflesh for beef, chevon formutton, mutton for venison, beef for mutton and occasionallythe flesh of the cat for hare or rabbit.Not difficult to differentiate the flesh and fat - animals in thecarcass form or in joints by means of anatomical confirmation.

ecognition of horseflesh or other meats in minced or insausage form depends on tests of chemical or biological

nature.!n the handling of meats and preparation of meat food productsattempts are sometimes made to substitute meat of lesserquality for that of higher quality with the object of deceivingpublic and gain more profit. The level of the mi"ing may varyfrom # to $$%. !f it is #&&% it is substitution.

Various types of meat being substituted as mentioned above - differentiateorrecognizeb ythreem ethods


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or recognize b y three m ethods.• They are

o Physical or physiological methods.o Chemical tests ando Biological tests

• These m ethods ar e al so classied as f ollows:o Physical and chemical techniques

Fatty acid pattern,Histidine d i-peptides an d

Direct probe mass Spectrometry.o Immunological techniquesAgar Gel Immuno Diffusion (AGID)Counter Immuno Electrophoresis (CIE)Enzyme Linked Immuno Sorbent Assay (ELISA)

o Electrophoretic TechniquesPolyacrylamide gel electrophoresis (PAGE)SDS Polyacrylamide gel electrophoresis (SDS PAGE)Polyacrylamide gel isoelectric f ocussing (PAGIF)Agarose i soelectric focussing (AGIF)

o DNA Assay Techniques

Ph6 ca* M th.' i l diff h i (


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'natomical differences - each species - carcass ( appearance -muscle ( fat colour, odour, te"ture and taste - provided - generaldifference between species - earlier days - food analysis.

)an be attempted - provided meats - form of joints and in carcassform

Carcasses of Different Species of Food Animals1# H."

• Nec* and the bones of limbs are longer than the o".• +ternum of horse is canoe shaped.• No diarthrodial joint between the first and second sternal ribs.• There are # pairs of ribs and are narrower than those of o".

2# B+**o assive muscles - nec* ( shoulder ( hindquarters - well-bredanimals.

o Nec* ( Ligamentum nuchae - thic*er ( stronger than - o".o 'nterior part – ischio-pubic symphysis - well developed ( forms

a distinct tubercle. !nguinal canals are patent.

3. Ox


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esser muscular development - bull - nec* and shoulderregion.

/ven covering - fat - e"terior. +crotal fat - prominent, nodular ( more or less pointed. 0elvis is narrow and usually contains a relatively large

quantity of fat. 1at is usually plentiful over the *idneys andalong the sub-lumbar region.

4. Cow Thigh - less rounded, very noticeable - hind quarters2sun*en round3 – pelvis, anterior tubercular pelvis broader -o".

4dder – present - removed triangular area of attachment isnoticeable on each side of midline of the abdominal wall.5eifers - udder - slightly developed and consists chiefly offat.

!n old cows the udder is soft, spongy, round and pendulous.

5. Sheep


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• Sh 5 ca"ca (:h th " ." : ) cha"act " -a9+ a t > 7 t" 9+t . – S C /at#

• Ra ca"ca - t ,+ h 96 ," at + c+*a"7 *.5 t - " , . – c< > h.+* " -

ligamentum nuchae - *a", a t". , - c< th c<> ,+ a* ca a* a" 5at t#

6. oat • G.at a" *. , a * a - * tt* S C /at& < 6 /at

a9+ a t 7 5.." ca"ca #• S C c. ct 7 t + - t c ca .t 9

" .7 c. 5* t *6# P *7 ./ ,.at *. , a a"".:#!. "og

Ca"ca - 5 , ca .t a *6 9 ta< - a 6 .th " a a* -. t c.+ t" - < * /t - ca"ca # B+t 7 :h th

< " .7 th " h.+* 9 . // c+*t6 t / cat .

D#FF$%$&'#'A'#O& OF CA%$CASS$S OF FOOD A(A)S


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Differentiation of Carcasses of "orse and Ox )arcass of the horse and o" may be differentiated by the followingdetails

#. !n the horse - unusual length - sides is noticeable, togetherwith the great muscular development of the hindquarters.

6. The thoracic cavity is longer in the horse7 this animalpossesses # pairs of ribs, whereas the o" has #8 pairs.

8. The ribs in the horse are narrower but more mar*edly curved.9. The superior spinous processes of the first si" dorsal vertebrae

are more mar*edly developed in the horse and are lessinclined posterior.

:. !n the forequarter, the ulna of horse e"tends only half thelength of the radius7 in the o" it is e"tended and articulates withthe carpus.

;. !n the hindquarter, the femur of the o" possesses no thirdtrochanter7 the fibula is only a small pointed projection, but in

the horse it e"tends two–third the length of the tibia.


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processes articulate - each other - si"th articulating -similar manner – sacrum - do not articulate in the o".

. The horse carcass shows considerable developmentof soft yellow fat beneath the peritoneum, especiallyin the gelding and mare, but in the stallion the fat isgenerally of a lighter colour and almost white. !n the

o" the *idney fat is always firmer, whiter and moreabundant than in the horse.$. 5orseflesh is a dar* red, initially brown or reddish

brown on e"posure to atmosphere the colour turns

bluish. arbling is absent in horsemeat7 it is firm butstic*y in nature due to high glycogen content.5orsemeat has a pronounced sweet taste, repulsive odour and well defined muscle fibre. =eef lac* thebluish tin e.


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CHEM CAL METHODS OR TESTS)onsist of the determination of


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) The content of glycogen in flesh, The percentage of linoleic acid in fat, The amount of iodine absorbed by unsaturated fatty acids in fatand

The refractive inde" of fat.

1# T t /." G*6c., C. t t ./ M at

5orseflesh is richer than the flesh of other food animals in glycogen. !n horsemeat glycogen is found in large quantities irrespective of age.• 5orse – &.: to #.& %• =eef - &.& to &.:%• 0or* and mutton - nil.

D a 7a ta,#. The flesh should be tested for the content of glycogen soon after theslaughter as it disappears from the flesh quic*ly.

6. iver of all food animals especially pig liver contains more glycogenwhen they are used in sausage ma*ing it gives a high percentage. +o

care must be ta*en in interpretation of results.

2# L .* c Ac T t !dentification of horse fat when admi"ed with beef or lard or suet -


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demonstrating the presence of # to 6% of linoleic acid >ther animal fats - not present in proportion higher than &.#%.

3# . 'a*+

=ased - amount - iodine absorbed - unsaturated fatty acids present - fat (varies - different animals. The iodine values of animal fats are

5orse fat - " 1at - 8 to 9; +heep 1at - 8: to 9;

0ig 1at - :& to


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'pplicable to mince or sausage meat*recipitation test

ost valuable one - based -development - certain antibodies - blood serum from

another animal. =lood serum - specific immuni?ed rabbits mi"ed - test tube - filtered e"tract -suspected meat.

Turbidity - solution first occurs - specified meat - present ( followed - definiteprecipitation.

0recipitation test is a protein reaction is of value for detection of flesh, organ fat

or intestines. @reatest value with raw meat - if meat - well boiled or fried - impossible to e"tractprotein from it

Complement fixation 4tili?es - normal component - serum complement - thermolabile mi"ture -

substances capable - reacting - any antigen–antibody system or lyses - antigen

agglutinated - antibody. )ertain antigen–antibody reaction - not produce any visible result e.g.

precipitation, agglutination - detected - fact that they use or fi" complement thusma*ing - no longer available for other reactions

)omplement - derived from guinea pig serum ( indicator system normallyconsists of sheep red cells and rabbit serum 2heated to destroy its own

complement before use in the test3.


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$)#SA !n / +!' technique relies - ability of antibodies to bind with specific antigens.4sed - blood grouping tissues typing and bacteriological wor* the / !+' test


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4sed - blood grouping tissues typing and bacteriological wor the / !+ test- applied - meat identification because - differences in protein composition -food animals are generally slight.

/ !+' - applied - detection of boar taint and soya in a variety of products. 'n e"tract 2containing antigens3 made from the meat sample underinvestigation - placed - petri dish or test tube ( adding different specific sera2containing antibodies3.

'ntibody - binds - corresponding antigen forms a comple" - afterwardsrecogni?ed and bound - second antibody containing an en?yme – catalyses -reaction - produce a colour.

!f - horsemeat - reaction – presence - specific horse serum. 0ositive identification - carried out - short time - ; h ( able to detect lowlevels of suspect meats, - as low as 8%.

Aiagnostic *it - routine use - commercial practice is available - usespolystyrene tubes and gives a mar*ed colour reaction in positive cases (colour - more accurately measured using a spectrophotometer.

0ossibility of adapting the test for coo*ed samples - being investigated >ther techniques - species identification include electron microscop+,electrophoresis, -arious chemical procedures, agar gel diffusion and

gas li/uid chromatograph+ .

$n0+me #mmunoassa+ $n0+me )in1ed #mmunosor2ent Assa+ $)#SA


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E ?6 a a6 –S+cc c h6 "., a - ?6 a7a *a9* 5 c / c ." / 8=+a t t // " t 5 c # A ?6 a a6# S=+a t tat 7 t " at . ./ a t , 96 5* + . //+ . . *6 5. 9* 96 +9 ct 7 c. 5a" . ./ " +*t 9 t: 7a" .+

*+t . ./ a 5* 8t"act a th. ./ ta a" ." .9 ct 7ata ca 9 " 7 /". ." .5h t cat + . 5" c 5 tat .

t ch =+ # E ?6 -* < + . ."9 t a a6 (EL SA) . ./7 "a* 5.: "/+* =+a t tat 7 + .*., ca* 5".c +" & :h ch a"

.t . t." 96 5" c 5 tat . # H " th a t 9. 6–a t , t "act ..cc+" a . . .* c+*a" *a6 " .9 * ? . a "t +"/ac a

/.**.: 96 a ./ a ?6 ch ca**6 9. t. . ./ th+ . " a, t # EL SA a : **- ta9* h t ch =+ & 5a"t c+*a"*6

c* ca* *a9."at." :h " t 5".7 "a5 a a*6 ./ 9 .*., ca*/*+ a t + /." a 6 a t , a a t 9. 9.th =+a* tat 7

c" , a =+a t tat 7 a, . t c 5".c +" # /.. c. t".**a9."at." & t ha 9 a55* : th . +cc t. th

t " at . ./ .6a 5".t at 5". +ct & :h ch "7 a a. * /." a** /.. ".t ##


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" ct EL SA


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Th t ch =+ 7.*7 th a55* cat . ./ 5 c -

5 c / c a t 9. . t. th 5".t (t t a t , )c.at . t. th 5*a t c +"/ac ./ c". t t" 5*at #Th " c., t . ./ a t , " +*t th /." at ../ a t , a t 9. 6 c. 5* 8 & :h ch a" t ct96 th " ?6 * < a t - ,G ." 5".t –A(a t 9. 6– t ct.") 5". +c , 7 9* c.*.+"" act . : th a +9 t"at # Th c.*.+" t t6

a +" .9 ct 7 *6 at a 5 c / :a7 * ,th a c". EL SA 5*at " a " a a9 ."9a c 7a*+ #Th a a =+at 9a c 6 t /." 5" + 5t 7

at 5 c at . ./ a9.+t 3#0 5 " c t a +*t "at . #


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DAS – EL SA - + . t" c EL SA

Th / " / EL SA ( + t" EL SA) " + " t


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Th /." ./ EL SA ( + . t" c EL SA) " =+ " t:.5 c – 5 c / c a t 9. 6 " a, t # Th 5*a t c +"/ac ./

th c". t t" : ** 5" -c.at : th . . 5 c / ca t 9. t. ca5t+" a t , /". a 5* 8t"act +" ,t:. ." th" " 5 at c+9at . # Th c. ( t ct.")

5 c – 5 c / c a t 9. a" th a55* t. /". th t.5-ha*/ ./ th a : ch# Th t ct." a t 9. ( ?6c. +,at a t 9. 6& a t - ,G ." 5".t –A) +9 =+ t*65". +c c.*.+" : th a +9 t"at # Th DAS–EL SA ha

5".7 5 c / c t6 a t 7 t6 a 5*.6 t.t ct 0# 5 "c t a +*t "at . ./ at# Th c. "c a**6

a7a *a9* A+ t"a* a ch c< at 6 t & t ,+ h c*. *6" *at 5 c * < th catt* 9+//a*.& h 5 ,.at ."h." . < 6#


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C. 5 t t 7 EL SATh th " 7a" a t ./ EL SA th c. 5 t t 7 /." # Th /."


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7.*7 th a55* cat . ./ 5" - c+9at at 8t"act (t ta t , c+9at : th < .: a .+ t ./ 5 c / c a t 9.

PBST) . t. th a t , -c.at 5*at # P" - c+9at .t ? . *6 h. .*.,.+ a t 9. a : ** t ** 9 /"

t. t "act : th th 5*at -9.+ a t , # S+9 =+ t*6& tha a6 c. 5* t th + +a* :a6 96 a , ?6 -

c. +,at a t ,G a +9 t"at /." th c.*.+"7 *.5 t#

th /." ./ EL SA& th a8 + c.*.+" 7 *.5 tcat ,at 7 " 5. a a,a t th 5. t 7 : th * tt*

c.*.+"# Th =+ c< a t 7 /." ./ EL SA 5".7th a t - 5 c a t "a a" a . . 5 c / c& c th

5a"at a t , -a t 9. 6 t "act . at th . .7a* t* 7 *& :h ch .9 6 th *a: ./ a act . :h "a// t6 a7 t6 c. "at . a" 5."ta t /." 5 c / c t6#


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. * ct" c F.c+ ,p5 at which proteins will be precipitated is the isoelectric point also species


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p5 at which proteins will be precipitated is the isoelectric point - also speciesspecific.

/lectrophoretic technique - utili?es - charge – surface - protein - drive - through agradient gel. 0olymeric compounds - ampholytes set up - p5 gradient.

0roteins applied - gel reaches a point where their surface charges - neutral, theisoelectric point . +ubsequent fi"ing ma*es the protein precipitated and fi"ed -same point as bands.

0attern of protein bands thus resulted for a particular meat e"tract is species

specific. Nature - pattern specificity - protein bands - utili?ed - identify meat species -determining - location, density and area - bands.

Bide range of animal species - identified - coo*ed meats by staining isoelectricfocusing gels - band pattern of the en?yme adenylate *inase 2'C3 ( creatine*inase 2)C3 provided the meat - not heated above #6&D) 2'C3 or #&:D) 2)C3.

/lectrophoretogram - heated horsemeat ( beef persisted - feature –differentiation

0roteins almost lost - configuration ma*ing mi"ed species interpretation difficult. !/1 patterns - coo*ed meat mi"tures - more comple" ( ma*e specificinterpretation difficult.


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ELECTROPHORET C TECHN UES ' powerful technique - protein separation - characteristic bandpatterns supporting gel differentiate meat species basis


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patterns - supporting gel - differentiate meat species - basis -electrophoretic mobility 2agar gel electrophoresis – '@/, starchgel electrophoresis – +@/ or polyacrylamide gelelectrophoresis – 0'@/3, isoelectric focusing – !/1 2ampholinegels–!/1 0'@/ or +A+-0'@/3 or both–mobility and 0! 2two –dimensional 0'@/3 of proteins.

S. + . c6* +*5hat PAGE (SDS PAGE)

Eariant – 0'@/ - used - separating protein sub-units (determining - molecular weights.

0olypeptide dissociated - proteins 2by heating3 bind - +A+ (+A+-polypeptide comple"es having same charge F mass ration- subjected - sieving polyacrylamide gel migrate according -molecular weights - polypeptides.

+A+ 0'@/ permitted identification of meats in meat mi"ture

and in commercial sausages


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T:.- . a* * ct".5h."4tili?es two completely independent parameters


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4tili?es two completely independent parameters20! ( molecular weight3 - separate comple"mi"tures or proteins.

1irst dimension - electro focusing - performed -ampholine 0'@/ plate

+tained strip containing proteins - interest inincubated in buffer having +A+ ( laid directly -moulded trench - +A+–gradient gel for seconddimension separation.

!n - 6-A – proteins - further separated 2highresolution3 - basis - sub-unit molecular weight -permitting identification between proteins - similar

isoelectric point


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.9 * , * a + .9*.tt , Technique - electro focusing - immobiline gels -


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complementary to traditional electro focussing methods

using carrier ampholytes - immobilines are acrylamidederivatives designed to co-polymerise with gradient isbased - relative concentrations of the immobiline at eachpositions.

)ovalently bound immobiline gradient 2narrow p5gradient3 allows higher resolution than the conventionalcarrier ampholyte-based p5 gradients.

ow conductivity - gel permits - application - high voltage

( p5 gradient not affected - long focusing times. Aiffusional or electrophoretic transfer of focused proteinsfrom - polyacrylamide gel onto nitro-cellulose membranes- order - ma*e them accessible - identifying reaction -

termed immunoblotting


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MMUNOCHEM CAL METHODS 5omologous responses of coctoprecipitins 2antibodies againstcoo*edFheat denatured proteins of meat3 - assessed by various


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immunochemical techniques - microhaemagglutination,

immunodiffusion 2agar gel diffusion-'@!A3, roc*etimmunoelectrophoresis ( counter immunoelectrophoresis 2)!/3( en?yme immunoassays 2different forms of / !+'3 recogni?ethe species of origin.

A t "+ • =iological product raised - phylogentically distant animal against

- specific protein 2immunogen3.• )ontains antibodies derived - lymphocytes.

• arge number - different ( distinct lymphocytes - stimulated -responses - antigenic sites - immunogen.

• )onsequently antisera containngi a heterogenous mi"ture -different antibodies - varying specificity ( affinity 2polyclonal

antibodies3

5eterogeneous antiserum - high dilution may behave -homogenous reagent since antibodies - highest affinities willonly be reacting.5 g it ti i d ifi ti 2di t


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5omogeneity - antiserum - increased - purification 2directabsorption3 - cross-reactions, affinity chromatography (inhibition by bloc*ing and concentration.

5omogenic antisera containing monospecific antibodies -varied applications - immunoassays - detect, distinguish quality,sensiti?e or neutrali?e homologous antigens.

M. .c*. a* A t 9. Techniques - producing monoclonal antibodies involveimmuni?ation – mice - specific protein ( harvesting - spleenwhen - mouse - optimally secreting antibodies.

+pleen - homogeni?ed - produce - sterile cell suspension -active lymphocytes 2= lymphocytes3. 1usion - lymphocytes (myeloma cells - induced - polyethylene glycol ( fused cells -selected - unfused - 5'T 25ypo"anthine – 'minopteridin –Thyronidine3 medium - cultures only hybridomas.

o

+urviving hybridomas - plated out - agar ( cultured - give singlecells clones.o )lones - cultured ( cultured medium - tested - presence -

antibodies


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antibodies.o 0ositive clones - recloned ( cultured - further investigationo +elected hybridoma cell culture - derived form a single cell -

antibody secreted - predefined nature ( specificity.

+ . //+ .

A,a" , * + . //+ .>uchterlonyGs 2#$$93 methods - double diffusion involving - use- agar coated plates - wells - both antigens ( antibodies -employed - recogni?e homologous antigens.Cnown ( un*nown samples - meat ( mi"ture - meat - differentdilutions - tested against - raised antisera.

eactants diffuse - gel ( positive reaction - indicated -formation - immuno precipitates 2opaque lines3 - point -

equivalence each antigen antibody pair


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C.+ t " + . * ct".5h." (C E)

0rinciple technique similar to '@!A


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0rinciple - technique - similar to @!A

Aiffusion of antigen and antibody is facilitatedby the application of low voltage current. /lectro-osmosis created - al*aline agar gelchanges - charge on gamma globulins2antibodies3 ( moves them towards cathode.

eat proteins moving towards anode produceprecipitin lines - point - equivalence.

+amples - meat diluted up to # in 8&& - readilydetected - )!/ ( utili?ed - detect low levels ofadulteration


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La+" * R.c< t + . * ct".5h." (R E) 'ssay - migration - antigens - electrophoreticfi ld l i i ib d b i l


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field - gel containing antibody - basis - electro

immuno diffusion or sometimes called electroimmunoassay.

'garose containing - antibody - poured - give -

gel - uniform thic*ness.Bells - punched out - gel at one end - varioussamples migrated - gel ( formed precipitationline – sample - characteristic roc*et shape base- height - antigen.@reater concentration - antigen will migratefurther - gel before reaching a point of

i l


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ppt for lpt 321.pptx

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