4 Factors Effecting Shelf Life and Storage Life of Fresh Fish

8/18/2019 4 Factors Effecting Shelf Life and Storage Life of Fresh Fish

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Factors influencing storage &shelf life of fresh fish

Icelandic InternationalDevelopment Agency (ICEIDA)

Iceland

United Nations University FisheriesTraining Programme (UNU-FTP)

Iceland

National A!atic "eso!rces "esearchand Development Agency (NA"A)

#ri $an%a

Department o& Fisheries andA!atic "eso!rces (DFA")

#ri $an%a

Quality and safety issues in fish handling-----

A course in quality and safety management in

fishery harbours in Sri Lanka

NARA, DFAR, !"DA and #N#-F$%


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Content

& 'hat is shelf life

& Factors affecting shelf life

& (o) to determine shelf life


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Learning Objectives

After this lecture *artici*ants )ill be familiar

)ith+

& Shelf life and factors affecting shelflife of fish ra)

materials

& some monitoring method to determine shelf life of

fish


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Shelf life

& Shelf life can be defined as the *eriod of time that the fish isfit for consumption

& $he limit of shelf life ie )hen the fish becomes unfit forconsum*tion can be determined based on sensory, chemical ormicrobial criteria

& $ime and tem*erature of storage can also be used as criteria todetermine the limit of shelf life

& Quality parameter rather than a safety *arameter


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& !om*osition

& ethod of catching

& %ost har.est treatment& %rocessing /eg free0ing, drying1

Factors affecting shelf life of fishFactors affecting shelf life of fish


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• Larger fish s*oil more slo)ly than small fish

& Flat fish kee* better than round fish& Lean fish kee* longer than fatty fish under aerobic storage& 2ony fish are edible longer than cartilaginous fish

Intrinsic factorsBiological properties influence fish composition

and shelf life


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Factors affecting composition of fish

Season S*a)ning /fat content 3 )ater1

Age 4oung, se5ually mature fish

Se5 Female 3 male

"n.ironment Feed, )ater tem*erature

2ody location Light 3 dark muscles

$y*e of fish Sharks, Ray fish contain highurea%elagic 3 demersal fish


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Method of catching

6 Long line 6 Trawl net 6 Gill net 6 Beach seine

Quick landing Not damaging to fish


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Post-harvest treatment

& (andling on board

%ro*er bleeding, gutting, cleaning

& - Rate of chilling /es*ecially fatty fish1 3 tem*eraturecontrol

& 7%, hygiene, SS8%

& %ackaging, storage 3 en.ironmental conditions

& #nloading 3 auctioning

& Loading, trans*ortation, retail sales 3 *rocessing


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Fish sho!ld reach the end cons!mer in minim!m time

Prolonged time lo'er the sensory !ality o& &ish

ime from the harvest


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Number of unacceptable lots (out of nine) of skipjack tuna transported

from Beruwala fishery harbour to Matugama & Horana

(!anegamarachchi" et al #$$#)

Microbiological !ualit" of fish


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Fluctuation of core temperature in s#ipjac# tuna handled atdifferent time periods along the Mathugama distribution


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E. coli counts of skinned skipjack tuna inmulti-day boats, at pier, in transportvehicles, at stall and at retailed stage



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Post harvest processing influences $ater activit" and

the rate of spoilage changes

Water activity Shelf life

ater activity a'

%resh fish a $'

ried fish a $

%ro*en fish a $+


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%andling on-board

1. Quick landing

2. Stunning !rain spiking !leeding

". Gilling # gutting

$. %lace in a chilling system for &uick cooling

'. Transfer to ice storage


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&ate of chilling ' temperature control

( ) ' ) 1( )

shelf life **S shelf life **S shelf life **S

)ra! claw 1(.1 1 '.' 1.+ 2., ".-

Salmon 11.+ 1 +.( 1.' ".( ".-

Sea !ream "2.( 1 +.( $.(

%acked cod 1$ .( 1 ,.( 2." ".( $./

)alculated 1 2." $.(

ariation o& #hel& li&e 'ith temperat!re

,ate of chilling -helf life

""#* "elative rate o& spoilageHHHuss" .''/


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Pac#aging methodsfor prolonging shelf life

+odi&ied atmospheric pac%aging

Mechanical gas flushing

and sealing with fish fillets

0acuum 1acking


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(ffect of pac#aging on the shelf lifeType of %roduct Storage

temp.Shelf life 0weeks

ir 3% 4%

4eat 0!eef pork poultry 1.( $.$5) 1 " 1 12 " 21

Lean fish 0cod pollockrockfish tre6ally

(.( $.(5) 1 2 1 2 1 "

7atty fish 0herring salmon

trout

(.( $.(5) 1 2 1 2 1 "

Shellfish 0cra!s scampi

scallops

(.( $.(5) , 2 , "

8armwater fish 0sheepshead

swordfish tilapia

2.( $.(5) , 2 2 $

Huss .''/


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(ffect of transportation onshelf life of fish

& %ro*er *acking 3 storage& #se of bo5es

& Adequate icing 3 cooling

& (ygienic conditions


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Methods to determine shelf life

& Sensory e6aluation 6 $orry or "# scheme for cooked fish, Quality nde5 ethod /Q1

for ra)9)hole fish

& )hemical analyses 6 #nfit for consum*tion )hen for instance $:2-N, $A, biogenic

amines ha.e reached a certain le.el

& 4icro!iological analyses

6 #nfit for consum*tion )hen $:! ; -


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Sensor" anal"sis )orr" scheme*Influence of different temperature during

storage )0°, !° and "#°$ on the shelflife

of haddoc# fillets

Adapted from: Olafsdottiret al., 2006

Ch i l d i bi l l i


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Chemical and microbial anal"sis%addoc# fillets stored at +,C .,C and /0,C

TVB-N

(Total volatile basic nitrogen)

TVC (total viable counts) and

Photobacterium phosphoreum (Pp)

Adapted from: Olafsdottiret al., 2006

Quality parameter 9escription Score


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1IM-schemefor Sea bass

Q y p p

Skin )olour: Bright, iridescent pigmentation (

appearanc Rather dull, becoming discoloured (head) 1

Green, yellowish, mainly near the abdomen 2

;dour Fresh seaweedy, neutral (

Cucumber, metal, hey 1

Sour, dish cloth 2

Rotten "

Te


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Changes in sensor" attributes during storage

"yes are

cloudy, sunken

"yes are clear

and conca.e

7ills ha.e

characteristic, red

colour, mucus

absent

7ills are discoloured

)ith e5cessi.e

mucus


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2 curve to predict the storage timeremaining for herring stored in ice or sea

$ater at +,C


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&eferences

& (uss, (( /ed1

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4 Factors Effecting Shelf Life and Storage Life of Fresh Fish