الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Cheddar cheese ~s the nrinci~le ingredl~ in the
processed cheese blend. In Egypt the use af imported Chedda-r’
cheese in the manufacture of pro.ceased cheese is expensive.
so., it was worth while to low.er the cost of manfa.ct.u rd.n g this
favorable type of cheese by using a new t echnf.que , Introduction
of retentates into nrocess cheese making haa been explored
.early. Recently, cheese base was suggested for repl.acement of
cheddar cheese in processed cheese ma.nufacture.
Therefore, this study wa.splanned to investigate the
II II
feasibility of the manufacture of cheese-base from ultrafiltrered
ski mmi lk pcwder to replace natural Cheddar cheese
in the processed cheese blend.
The research was carried out in three parts:
Part I: Local and imported processed cheese samples representea
13 variety were randomly coliected from the Egyptian
market for evaluation. The chemical., physical and
bacteriological properties showed great-variations.
If 11 Correlation coefficient r values between texture and
melting properties and some parameters of processed
cheese were calculated.
Part II:B1.ends from different proportions of young and mature
Cheddar cheese (5 and 10 months’ oLd) were manufactured
to processed cheese to sel.ect the more suitable blend
.hichgive a processed cheese with good properties.
The chemical., physical and organa.lep.tic evuuations
for the resultant processed cheese showed that the
more suitable bl.end was consisted of 75 % yQ;ung +
~5 % mature Cheddar cheese. This was selected as
a control in part III.
Part III: In this part a cheese-base from ultra-filtered recoD.-
stituted skjmmiIk was produced to repl.ace to-tally
or partially the Cheddar cheese in processed cheese
blends. Then the resultant processed cheese was
tested chemically, physically, microbiologically
and sensory evaluted.
The results of this part summarised as follows:
1- For making the cheese bases, reconstituted skimmilk
(20 %) was ultrafilterated followed by
dia.filtration. The retenta.te 12asteurised.,.
fermented” coa-gu1..a..tewdith r.e.naets. then puaped
II II through Alcurd machine for cutting,. strrilig and
removing whey.
The resultant curd divided into tWQ panions.
The first one was salted” pressed and packed to,
produce ” cheese-base I II•
The second portion was trea.ted with ” J.I Savorase-A
proteolytic enzyme, salted, pressed and packed
It II to produce cheese-base II •
2~ Cheese-base I and II w.ere stqred for 2.weeks at laC and
tested perio·dically”’a;s they comparedwith Che.dda([c”aeeae ,
They compared wi.th Cheddar cheese. They were analysed for
chemical com.position, microbiological q..uality and eva.tua.t ed
organolyptically as well as protein ·cie&radauWL .. was
follow.ed through ri};lening.
3- It was found that 2. w.eeksare enough period for ripening
the cheese base.
4- A new.’processed cheese blends were suggested by replacing
young and mature Chadda.r cheese with cheese-base I or
cheese-base II.
5-- The resultant processed cheese w.ere stored at 10” 20 and
30°C and analysed when fresh and a.f ter 3 and 6. months.
6- The chemical composition of the processed cheese from
different blends showed somevariation.s but all of them
lies within the Egyptian legal standards for processed
cheese. pH values of different cheeses also lies within
the best range suggested for this type of cheese (5.41 to
7- The differences in chemical analysis occurred through
stor.age at different temperatures w.ere evaluated statistically.
8- Microbiological properties of processed cheese from different
blends showed soae varia.tiona clUe to the ’Various
treatments and the storage at different tem.peratures-
Generally} all. cheeses considered of good q.uality and
there was no micro.bio~Q.gi.caldefects.
9- The Rhysica~ properties are very important in processed
cheese. The oil separation defect was not detected in
all tested cheeses. Melting index showed great variations
towards the different treatments. A~so the penetrom.eter
zeadi.ng was a..ffected by the composition of the blend as
well as the storage period. The consistency 0 f processed
cheese was affected by the variations in the blend com.psition
as we~l as storage at different tem12eratures.
10- The texture of the processed cheese was evalua.ted using
the instI’OJl machine. from the texture. profile, the hardness.
cohesiveness. gumminess. spr-Lngi.ne aa, chevdness and adhesiveness
were calculated.
11- The col.our of processed cheese from. different bl.ends wa.s
determined s:gectrophotometrically and expressed as O.D.
12- Analysis of variance (F-test) was carried out fo.r al.l
characteristics between treatments storage time,. storage
time x storage temperature and treatment x storage tiJa.e.
13- statistical analysis. showed the correlation coefficients
between the physical. prope r-td.e s and ehead.ca),param.eters..
14- Sensory evaluation was done b;y the panelists and evaluated
sta tistically. The resultant processed cl\~ese from all
bl.enda show.edan acceptahle cheeses and with good keeping
q.uality.
It was concluded that R!,?cessed cheese can successfull.y
manufacture using the ul trafiltrat:ed ski mm; l.k :gowder retentate
a.fter increasing its protein content and ri:2ening for 2 weeks
(cheese-base I) 0·1’ with the a.ddition o.r Savora.se proteolytic
enZ3”M-e (chee se.-baee II) for replacing partially Cheddar cheese
up to 75 % without any defects in its chemi.cak, :physi~ •.
microbiological and o.z-gano.Lep td,c properties.