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Yield and sensory evaluation of the processed cheese from sudanese white cheese

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Abstract

Trails for manufacturing the processed cheese from the Sudanese white cheese is done during this study. The processed cheese was made from Sudanese white cheese with different ripening time (15 days and 30 days) from milk with different fat present (2.2% and 4.4%). At time of processing the processed cheese was packed into two types of packaging (glass and plastic) and stored at 4º C for 3 months. The yield of the processed cheese and the Sudanese white cheese made out of it from 4.4 fat % of milk after 15 and 30 days ripening were 2.850 Kg and 1.75 Kg and 2.750 Kg and 1.50 Kg respectively, while that made from 2.2 fat % yielded 2.0 Kg and 1.25 Kg and 2.0 Kg and 1.2 Kg, respectively. On other hand as judged by the panelists the colour, taste, flavour, texture and saltiness of the processed cheese showed noticeable changes during storage period. The processed cheese made from Sudanese white cheese after 15 days ripening was more stable and acceptable. Also glass packaging was more acceptable compared to plastic packaging (70% and 30%, respectively). The overall acceptability showed that the processed cheese made from white Sudanese cheese after 15 days ripening from milk with 2.2 fat % was the best of the cheese tried (4.4%). Hence, the present study concluded that the Sudanese white cheese could be further reprocessed to obtain the processed Sudanese cheese.
Research Journal of Animal and Veterinary Sciences, 2: 47-52, 2007
© 2007, INSInet Publication
Corresponding Author: El Zubeir Ibtisam, E.M., Department of Dairy Production, Faculty of Animal Production, University
of Khartoum. P. O. Box 32, Postal code 13314, Khartoum North, Sudan.
E-Mail: Ibtisammohamed@hotmail.com Fax: +249 185 321246
47
Yield and Sensory Evaluation of the Processed Cheese from Sudanese White Cheese
Nour El Diam, M.S.A. and El Zubeir Ibtisam, E.M.
Department of Dairy Production, Faculty of Animal Production,
University of Khartoum. P. O. Box 32, Postal code 13314, Khartoum North, Sudan.
Abstract: Trails for manufacturing the processed cheese from the Sudanese white cheese is done during
this study. The processed cheese was made from Sudanese white cheese with different ripening time (15
days and 30 days) from milk with different fat present (2.2% and 4.4%). At time of processing the
processed cheese was packed into two types of packaging (glass and plastic) and stored at 4º C for 3
months. The yield of the processed cheese and the Sudanese white cheese made out of it from 4.4 fat %
of milk after 15 and 30 days ripening were 2.850 Kg and 1.75 Kg and 2.750 Kg and 1.50 Kg
respectively, while that made from 2.2 fat % yielded 2.0 Kg and 1.25 Kg and 2.0 Kg and 1.2 Kg,
respectively. On other hand as judged by the panelists the colour, taste, flavour, texture and saltiness of
the processed cheese showed noticeable changes during storage period. The processed cheese made from
Sudanese white cheese after 15 days ripening was more stable and acceptable. Also glass packaging was
more acceptable compared to plastic packaging (70% and 30%, respectively). The overall acceptability
showed that the processed cheese made from white Sudanese cheese after 15 days ripening from milk with
2.2 fat % was the best of the cheese tried (4.4%). Hence, the present study concluded that the Sudanese
white cheese could be further reprocessed to obtain the processed Sudanese cheese.
Keyw ords: Sudanese white cheese, processed cheese, yield, sensory evaluation, storage, ripening,
packaging
INTRODUCTION
There are two main types of cheeses in Sudan
namely Sudanese white cheese (Gibna bayda) and
braided semi hard cheese (Mudaffarra). Other types of
cheese provided recently by Sudanese industries, are
Mozzarella and Roome. However the processed cheese
is not yet produced by the Sudanese industry, as this
cheese could be stored for longer periods and excess
milk could be converted into processed cheese.
Traditionally, processed cheese was made by heating
and stirring mixture of natural cheese, chelating salts,
fat and water at temperature between 70 and 95º C for
short time about 5 to 10 minutes . Turhan and
[13]
Dervisoglu reported that processed cheese made by
[17]
using Ior cheese (produce from skim milk), butter,
dried skim milk and tri sodium citrate. They concluded
that 20% Ior cheese addition resulted in a high quality
and spreadable processed cheese. Soft cheese was used
to manufacture spreadable processed cheese by adding
3.5% emulsifying salts and 15– 25% water and 0.08%
Arabic gum . They concluded that locally produced
[5]
soft cheese in Iraq could be used instead of imported
semi-hard cheese to make processed cheese of
acceptable quality.
White cheese made by coagulating heated milk
(90 ºC) with a 2.5% citric acid solution to pH 5.5 have
been reported to be used in a processed cheese
formulation blend up to level of 33% . They
[6]
concluded that the appropriate levels and the right kind
of the emulsifying salt, together with an optional
proportion of white cheese in the blend, could produce
processed cheese product with good rheological
characteristics. There are other reports of cheese like,
Queso blanco cheese and a Latin American Counter
part of Asian Paneer, have also been used for
processed cheese manufacture . Moreover, emulsifying
[9]
salt and water were added in varying proportions
before processing for 15– 25 minutes at 85º C. T heir
results indicated that the cheese with 1.5 % sodium
citrate + 35 % water and 3.0 % sodium citrate + 50%
water yielded the best products with smooth texture
and mouth feel and good flavour characteristic.
Cheese made from pasteurized milk received the
highest organoleptic scores after 90 days at room and
refrigerator temperature (92% and 88%, respectively).
However cheese made from raw milk received the
highest organoleptic scores after 60 days at room and
after 90 days at refrigerator temperature . The storage
[3]
at room temperature for 4 months of market processes
Res. J. Anim. & Vet. Sci. 2: 47-52, 2007
48
cheeses had a more pronounced effect on the quality
and reheological properties of processed cheeses . On
[4]
the other hand Singh and Kanawjia concluded that
[14]
the sensory characteristics of flavour and texture of
processed cheese decreased during storage at 37º C.
Similarly Hamed et al. reported that the score for
[4]
flavour, texture, colour and general appearance of fresh
and stored processed cheese showed a general tendency
to decrease throughout the storage period.
Tewari et al. used trisodium citrate and disodium
[16]
hydrogen phosphate as emulsifiers in 1: 0, 0: 1, 2: 1,
1: 1 and 1: 2 and they found that the most suitable
TSC: DSHP combination was 1: 2, when added at 3%.
Disodium phosphate and trisodium citrate produced
properties closest to those of all fat reference cheese
with trisodium citrate providing the most meltability .
[15]
On the other hand Siew et al. reported that the dairy
[13]
proteins play the important role of emulsifiers the
majority of the proteins are caseins, the emulsification
potential of which is improved by the use of chelating
salts. They added that the solubilized casein is able to
interact with water and fat under agitation and heating
and on cooling will form a gel structure.
This study is a trial to produce processed cheese
from Sudanese white cheese with different fat levels
and different ripening periods. Also the shelf life and
package materials for the processed cheese were
evaluated.
MATERIAL AND METHODS
Sources of Milk Rennet and Salts: Fresh cow’s milk
(30 liters) was brought from Khartoum University farm,
Rennet tablets were obtained from Chr- Hansen’s Lab
(Denmark), the salt was purchased from the local
market and di-sodium phosphate was a product of
Sigma Chemical Company.
Adjustment of Milk Fat and Cheese Manufacture:
The adjustment of milk fat to be processed and the
manufacture of cheeses were done at the Department of
Dairy Production, Faculty of Animal Production,
University of Khartoum during the period of November
2002 to February 2003. The milk was adjusted to two
different fat % (4.4 and 2.2) using the cream separator.
Manufacture of the Sudanese White Cheese:
Sudanese white cheese was made as described by
Osman from the milk with the two levels of fat %.
[11]
Milk was heated to 45° C then rennet (0.07% gram/L)
was dissolved in little amount of water and added to
the milk at 40º C . Salt (7% gram/ L) and the milk
were stirred for 5 minutes then the mixture was left to
develop a curd. The curd after coagulation was cut by
stainless steel kitchen k nife and kept for 5 minutes to
separate the whey, which was collected and kept in
room temperature. The curd was collected and
transferred into clean wooden moulds lined with clean
clothes then pressed with 1 kg weight over night. In
the next day the curd was cut to cubes and weighted
then transferred into plastic cans and the whey was
added. The cheeses that made from low (2.2 %) and
high fat (4.4 %) content of milk were stored at room
temperature for ripening to both 15 and 30 days.
Manufacture of the Processed Cheese: The cheeses
were cut into small pieces using stainless steel. Then
3% of di-sodium phosphate and 50% of distilled water
were added. It was then mixed using a mixture at
water bath steam (80º C for 5 minutes). Processed
cheese were packed into two types of packaging
(plastic pack and glass pack) and stored at 4º C.
Sensory Evaluation: Panels of 10 untrained panelists
from the staff and students of the Faculty of Animal
Production who are familiar with cheeses were asked
to judge on the quality of the processed cheese using
a sensory evaluation sheet.
RESULTS AND DISCUSSIONS
Comparison between white Sudanese cheese and
Processed Cheese Yield: As shown in Table 1 the
yield of Sudanese white cheese made from 30 liters
milk with 4.4 fat % was 1.750 Kg after 15 days
ripening and was 1.5 Kg after 30 days ripening.
Moreover the yield of Sudanese white cheese made
from 30 liters milk with 2.2 fat % was 1.250 Kg after
15 days ripening and was 1 .2 Kg after 30 days
ripening. The yield of the processed cheese made from
Sudanese white cheese with milk fat of 4.4% after 15
days ripening was 2.850 Kg and after 30 days ripening
was 2.750 Kg. Moreover, the yield of the processed
cheese made from Sudanese white cheese with milk fat
of 2.2 % after 15 days ripening was 2.0 Kg and at 30
days ripening was 2.0 Kg (Table 1). The Sudanese
white cheese which was very popular in Sudan was
used in this study (Table 1) as a raw material to
manufacturing the processed cheese that has an
increasing acceptability in Sudan now a days. This is
due to the greatest shifts that happen in the feeding
habits of a lot of consumers and the change towards
the fast food is increasing and become so common due
to shift of live as most of households went to work
and/or study. This leads to the increasing demand of
such cheeses, in addition to the increased numbers of
foreigners in the country.
The present study revealed that it was reasonable
to produce the processed cheese with acceptable quality
from the Sudanese white cheese. The processed cheese
Res. J. Anim. & Vet. Sci. 2: 47-52, 2007
49
Table 1: Effect of repining and fat level of milk on yield of processed and non processed Sudanese white cheese
4.4% milk fat 2.2 % milk fat
Cheese type ----------------------------------------------------------- -------------------------- ---------------------------------
15 days repining 30 days repining 15 days repining 30 days repining
Sudanese white cheese (Kg) 1.75 1.50 1.25 1.20
------- ------ ------- ------ --------------------------------------------------------------------------------------------------------------------------------------------------------------
Processed cheese (kg) 2.85 2.75 2.00 2.00
Table 2: Sensory evaluation for the processed cheese
Measurements Colour Flavour Taste Body Overall acceptability
------------------------------------------------------------------------ ------------------------------ ---------------------------- ------------------------------ -------------------------- ----------------------------
Ripening Packaging type Fat Storage period 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4
15 days Glass 4.4 % 1 - - - 100 - 20 80 - 100 - - - 100 - - - - - 40 60
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Glass 4.4 % 2 - - - 100 - 50 50 - 40 60 - - 100 - - - - 10 40 50
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Glass 4.4 % 3 - 10 40 50 20 30 30 20 - 40 50 10 80 20 - - 10 40 50 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Plastic 4.4 % 1 - - - 100 - 20 80 - 100 - - - 100 - - - - 10 30 60
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Plastic 4.4 % 2 - - - 100 - 50 50 - 40 60 - - 100 - - - - 30 50 30
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Plastic 4.4 % 3 - 20 30 50 30 50 10 10 - 20 40 40 70 30 - - 40 40 20 -
--------------- -------- -------- -------- ------- -------- -------- -------- ------- -------- -------- -------- ------- -------- -------- -------- ------- --------- ------- -------- -------- -------- ------- -------- -------- ------- -------- -------- --------------------
15 days Glass 2.2 % 1 - - - 100 - 50 50 - 100 - - - 100 - - - - - 40 60
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Glass 2.2 % 2 - - - 100 - 40 60 - 50 50 - - 100 - - - - - 50 50
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Glass 2.2 % 3 - 10 30 60 10 40 50 - - 40 60 - 90 10 - - 10 40 50 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Plastic 2.2 % 1 - - - 100 - 50 50 - 100 - - - 100 - - - - 20 40 40
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Plastic 2.2 % 2 - - - 100 - 50 50 - 30 70 - - 100 - - - - 30 40 30
------------------------------ -------- -------- ------- -------- -------- -------- -------- -------- ------- -------- -------- -------- -------- -------- ------- -------- -------- -------- ------- -------- -------- -------- -------- -------- ------- -------- -------- ----
15 days Plastic 2.2 % 3 - 20 30 50 50 20 30 - - 40 30 30 80 20 - - 40 40 20 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Glass 4.4 % 1 - - - 100 - 10 60 30 - 90 10 - 100 - - - - - 30 70
------------- ------- -------- -------- -------- -------- -------- -------- -------- ------- -------- -------- -------- ------- -------- -------- ------- -------- -------- -------- ------- --------- ------- -------- -------- -------- ------- -------- ----------------------
30 days Glass 4.4 % 2 - 30 70 - 10 40 50 - - 40 60 - 60 30 10 - 20 40 40 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Plastic 2.2 % 1 - - - 100 - 10 60 30 - 90 10 - 100 - - - - - 30 70
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Plastic 2.2 % 2 - 50 50 - 50 50 - - - 30 70 - 70 20 10 - 40 40 20 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Glass 4.4 % 1 - - 40 60 - 50 50 - - 70 30 - 100 - - - - - 30 70
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Glass 4.4 % 2 - 50 50 - - 50 50 - - 50 50 - 60 30 10 - 20 40 40 -
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Plastic 2.2 % 1 - - 40 60 - 50 40 10 - 70 30 - 100 - - - - - 30 70
--------------------------- -------- -------- -------- -------- -------- ------- -------- -------- ------- -------- -------- -------- -------- -------- ------- -------- --------- ------- -------- -------- ------- -------- -------- -------- ------- -------- -------- -------
30 days Plastic 2.2 % 2 - 80 20 - - 40 60 - - 40 60 - 60 30 10 - 40 40 20 -
Colour :- Flavour :- Taste :- Body :- Over all acceptability :-
1/ Un ac cept able 1/ Bland 1/ Abse nt acid 1/ S moot h body 1/ No t acc epta ble
2/ Moderately unacceptable 2/ Slightly intense 2/ Slightly acid 2/ Slightly body 2/ Moderately unacceptable
3/ Slight ly acce ptable 3/ Mo derat ely inte nse 3/ Acid 3/ Har sh bod y 3/ Slight ly acce ptable
4/ 4/ Ac cept able 4/ Ext remely int ense 4/ Exc essive a cid 4/ Pas ty 4 / Accep table
is considered as a stable product with reasonable shelf
life, moreover different types cheese can be used in the
processed cheese . This is a very promising result
[5]
since it would help to minimize and stop the
importation of the expensive pro cessed cheese. This
also utilize and safe the huge quantities of milk which
produce in the rural areas and further processing it in
towns to reasonable longer shelf life cheese (processed)
instead of the Sudanese white cheese.
During the present study comparison between the
processed cheese and white Sudanese cheese on the
yield showed that the processed cheese yielded more
quantities. This is acceptable result as the Sudanese
white cheese was the raw material for the processed
cheese. In spite of the lost of moisture during heating,
there was 50 % of the distilled water added, which
gives more yield. However the fat level did not affect
significantly (P> 0.05) the yield of the processed
cheese, which supported Dimitreli and T homareis[1]
who reported that fat was found to have non significant
effect on the rheological behaviour of processed cheese.
Similarly Lee et al. reported that the change in the
[7]
viscosity profile during cooking occurred in processed
cheese made from a typical formulation as well as
from a fat-free model system. They concluded that this
might indicated that the 'creaming reaction' is primarily
a protein-based interaction, which takes places with or
without the presence of fat and the observed viscosity
profile can be explained in terms of changes in the
protein structure of the molten processed cheese during
processing. On the other hand the reduction in fat
content resulted in significant increases in the mean
Res. J. Anim. & Vet. Sci. 2: 47-52, 2007
50
Table 3: A cceptability of salt level and packaging of the processed cheese
Measurements Saltiness Packaging
---------------------------------------------------------------------------------------------- --------------------------------------- - ------ --------------- ------ -----
Ripening Packaging type Fat Storage period (month) 1 2 3 4 1 2
15 days Glass 4.4 % 1 - 50 50 - 20 80
------- ------ ------- ------ --------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Glass 4.4 % 2 - 70 30 - 20 80
---------------------------------------------------------------------------------------------------------------------------------------------------------- ------ ------- ------ -----------
15 days Glass 4.4 % 3 40 60 - - 20 80
-------------------------------------------------------------------------------------------------------------------------------------- ---------- ---------- ------------------------------
15 days Plastic 4.4 % 1 - 50 50 - 20 80
-------------------------------------------------------------------------------------------------- ---------- ---------- ------------------------------------------------------------------
15 days Plastic 4.4 % 2 - 70 30 - 20 80
------------------------------------------------------------------------- ---------- ---------- -------------------------------------------------------------------------------------------
15 days Plastic 4.4 % 3 40 60 - - 20 80
--------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------------------
15 days Glass 2.2 % 1 - 50 50 - 20 80
------- ------ ------- ------ --------------------------------------------------------------------------------------------------------------------------------------------------------------
15 days Glass 2.2 % 2 - 70 30 - 20 80
----------------------------------------------------------------------------------------------------------------------------------------------------------- ------- ------ -------------- --
15 days Glass 2.2 % 3 40 60 - - 20 80
----------------------------------------------------------------------------------------------------------------------------------- ---------- -------------------------------------------
15 days Plastic 2.2 % 1 - 50 50 - 20 80
----------------------------------------------------------------------------------------------------------- -----------------------------------------------------------------------------
15 days Plastic 2.2 % 2 - 70 30 - 20 80
----------------------------------------------------------------------- ------------------ -----------------------------------------------------------------------------------------------
15 days Plastic 2.2 % 3 40 60 - - 20 80
------------------------------------ ------------------ ----------------------------------------------------------------------------------------------------------------------------------
30 days Glass 4.4 % 1 20 40 40 - 20 80
------- ------ ------- ------ --------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Glass 4.4 % 2 70 30 - - 20 80
------------------------------------------------------------------------------------------------------------------------------------------------------------------- ---------- -----------
30 days Plastic 2.2 % 1 20 40 40 - 20 80
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Plastic 2.2 % 2 70 30 - - 20 80
---------------------------------------------------------------------------------------------------------------- ------------------------------------------------------------------------
30 days Glass 4.4 % 1 20 40 40 - 20 80
-------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------------
30 days Glass 4.4 % 2 70 30 - - 20 80
-------------------------------- ---------- ---------- ------------------------------------------------------------------------------------------------------------------------------------
30 days Plastic 2.2 % 1 20 40 40 - 20 80
------- ------ ------- ------ --------------------------------------------------------------------------------------------------------------------------------------------------------------
30 days Plastic 2.2 % 2 70 30 - - 20 80
Saltines :- Packaging :-
1/ Moderately salted 1/ Plastic
2/ Salted 2/ Glass
3/ Over salted
4/ Too salty
melt time and a decrease in the mean flowability of the
melted cheese and the stretchability of the full fat
cheese (FFC) increased most rapidly attaining mean
values which were significantly higher than those of
the other cheeses at 15 and 30 days .
[2]
Processed Cheese Acceptability: Sensory evaluations
of the processed cheese for all tried cheeses showed
decrease values during storage (Table 2 and Table 3).
According to the panelist, the best colour score was
found in the processed cheese made from Sudanese
white cheese after 15 days ripenin g from milk with 2.2
fat % and packed in glass (Table 2). The processed
cheese made from Sudanese white cheese after 15 days
ripening from milk with 4.4 fat % and packed into
glass revealed the best flavour during the storage
(Table 2). This supported Muir et al. who reported
[10]
that differences in cheese flavours are due to fat
content. The taste of the processed cheese showed
increase scores from absent of acid to excessive acid
during storage period (Table 2). It was clear that the
processed cheese that packed into plastic showed
increase in acid taste compared to the glass packaging
(Table 2). This might be due to the glass packaging
that was sterilized before used and they were more tied
than the plastic ones.
The texture changed during storage periods showed
decrease (Table 2). The processed cheese made from
Sudanese white cheese after 15 days ripening revealed
the best score even with different fat % and different
packaging. This agreed with Singh and Kanawjia and
[14]
Hamed et al. who reported that the sensory
[4]
Res. J. Anim. & Vet. Sci. 2: 47-52, 2007
51
characteristic of flavour and texture of the processed
cheese decrease during storage of the cheese. However
Schar and Bosset mentioned that structure and
[12]
flavour of processed cheese during storage at room
temperature were slowly changed.
The saltiness taste was found to be clear and that
slight changes in salt was noticed by the panelist. This
might be due to added emulsifier salts or it might be
due to the differences between the panelist tastes.
However, no changes in salt were found during
processing of the processed cheese (Table 3). Swenson
et al. added that however significantly higher
[15]
concentration of ash and phosphorus were detected in
bitter cheese samples as it was noticed that the
respective batches of processed cheese slices had been
produced apparently using an over does of specific
emulsifying agent . On the other hand Siew et al.
[8] [13]
reported that the dairy proteins play the important role
of emulsifiers the majority of the proteins are caseins,
the emulsification potential of which is improved by
the use of chelating salts.
Packaging of the processed cheese into glass
showed more acceptability than the plastic (Table 3).
Moreover, they reported that sensory scores of the
processed cheese were decrease during storage and the
rate of decrease being slowest in samples stored in
glass. Moreover Schar and Bosset reported that the
[12]
changes with age of processed cheese are influenced by
four main factors: product composition, processing,
packaging and storage conditions (time and
temperature).
The present study concluded that there is
possibility of using the Sudanese white cheese as a
raw material for preparation of the processed cheese.
Moreover it yielded more quantity that will increase
the incomes, in addition to the high prices of
the processed cheeses. However, the panelist
showed that the most acceptable sample of the
overall acceptability was the processed cheese made
from Sudanese white cheese with 15 days ripening
with 2.2 fat% of milk and packed in glass material
(70%). This might indicated that the higher present of
fat on cheese is not required so the excess fat
could be manufactured into the expensive products
(butter, cream and ghee). T he shorter ripening time is
better than the longer as long as pasteurization is not
practiced, in order to obtained good quality
products with maximum duration. From the results
of the present study we encourage production of
the processed cheese in Sudan from the Sudanese
white cheese as the processing of the cheese maximizes
the utilization of all prod uced cheese, since the small
on uneven pieces can be use. Further work are needed
and recommended on using the natural sources in
Sudan as emulsifiers to produce the processed
cheese from Sudanese white cheese and to understand
in more details the optimum conditions for its
manufacturing.
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... Low fat milk products, particularly low fat cheese represents a good choice for the development of new products with functional properties because the consumers are always looking forward to desirable and healthy products [6]. The higher present of fat on cheese is not required so the excess fat could be manufactured into the expensive products like butter, cream and ghee [7]. Low fat cheeses are usually characterized as having poor body, flavour, and functional properties because of high moisture and low salt. ...
... It was reported that in cheese, the removal or reduction of fat adversely affect the flavour and texture [48]. However the overall acceptability showed that the processed cheese made from white Sudanese cheese after 15 days ripening from partially skimmed milk (2.2 %) was better than that made with full milk fat (4.4%) [7]. Also it was reported that the full-fat Edam cheese had more intensive colour, tender consistency and better taste than the reduced-fat cheese [49]. ...
... Slightly higher sensory scores were reported in some of the cheese samples kept at room temperature and packed into plastic container. The processed cheese packed into glass received more acceptability than the plastic container [7]. On the other hand, hundreds types of cheeses are produced in the world, their styles, textures and flavours depend on the origin of milk, animal's diet, butterfat content, bacteria and mold, the processing, and aging conditions [53]. ...
... However, the findings disagreed with those reported that there was significant change in color, flavor and texture of Sudanese white cheese during the storage [29]. Similarly, it was reported that the scores for color, taste, flavor, texture and saltiness of the processed cheese showed noticeable changes during storage period [44]. On the other hand, it is very difficult to produce long-life tofu, since the smooth and fragile texture of tofu is easily destroyed by retort sterilization [4]. ...
... decrease in the protein content during the storage. Similarly it was reported that the protein content of Sudanese white cheese decreased during storage at cold temperature [5][6][7][8][9][10][11][12][13][14][15]. The decrease in protein content during pickling was a direct result of protein degradation leading to the formation of water-soluble compounds, some of which were lost in pickling. ...
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... The microbiological picture as shown in Table 2revealed that the locally produced cheese is more or less similar in the properties to the imported one. This suggested that it is reasonable to produce the processed cheese with an acceptable quality in Sudan, supporting the previous study that used Sudanese white cheese for production of the processed cheese (Nour El Diam and El Zubeir, 2007). They also reported that the huge quantities (1996) concluded that locally produced soft cheese in Iraq could be used instead of imported semi-hard cheese to make processed cheese of acceptable quality. ...
... The constant increase of moulds and yeasts during storage might be due to the fact that yeasts and moulds counts could metabolize lactic acid and lower pH value . However Nour El-Diam and El-Zubeir, (2007) found that the heat treatment and processing improve the cheese quality via reducing the counts of yeasts and moulds. The coliforms count decrease significantly with the storage period. ...
... However, vacuum packaging is currently not feasible in rural areas of Sudan where the majority of cheese is produced. In a laboratory trial, Nour El Diam and El Zubeir (2007) reported that glass packaging was more acceptable compared to plastic packaging (70% and 30%, respectively). Ceylan et al. (2003) studied the microbiological quality of sikma cheese (white pickled Turkish cheese) and found that the average coliform count was 5.99 log cfu/g, the high coliform content was attributed to the post-contamination during storage. ...
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