Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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METHOD OF MAKING FRESH CHEESE WITH ENHANCED
MICROBIOLOGICAL SAFETY
FIELD
[00011 Described herein is a high moisture, preserved cheese product having
enhanced microbial food safety and methods of making the high moisture,
preserved
cheese product. Enhanced microbial food safety is achieved by using a
combination of
organic food preserving acids, a nisin component and an enzyme system.
BACKGROUND
[0002] Food processors have long felt the need for methods to prolong the
shelf life
of foodstuffs and/or increase microbiological stability of such foodstuffs. By
increasing
the amount of time a foodstuff is stable, processors can mitigate inventory
losses due to
spoiled foodstuffs. Prior methods, such as, the use of packaging,
preservatives, and/or
specific storage parameters (e.g., refrigeration) have been used to stave off
spoilage.
[0003] Bacterial contamination of foods is known to be responsible for
spoilage
and for the transmission of food borne illness. In particular, Listeria
monocytogenes has
been associated with such foods as raw milk, cheeses (particularly soft-
ripened
varieties), ice cream, raw vegetables, fermented raw meat sausages, raw and
cooked
poultry, raw meats (of all types), and raw and smoked fish. Listeria
monocytogenes is a
psychrotrophic food borne pathogen which is very widespread in the environment
and in
foods. The ability of Listeria monocytogenes to grow at temperatures as low as
3 C
permits multiplication in refrigerated foods.
[0004] Bacteriocins are antimicrobial peptides that are produced by bacteria
and
which have bactericidal action against closely related species. One of the
most
extensively characterized bacteriocin is nisin which is produced by a lactic
acid type
bacteria and which may be used to prevent growth of Gram-positive bacteria in
a wide
variety of different food products, particularly dairy products (see, e.g.,
U.S. Patent
Publication No. 2008/0152757; U.S. Patent 2,744,827; U.S. Patent 4,584,199;
U.S.
Patent 4,597,972; and U.S. Patent 5,527,505).
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[0005] Currently, most commercial refrigerated unaged, high moisture cheese
products with relatively high pHs (e.g. above about 5.0) have a very limited
shelf life and
do not have secondary barriers to psychrotrophic pathogens. However, there
have
been efforts to enhance the microbiological safety of such cheese products.
Generally,
known methods to enhance microbiological safety in food products include
cooking,
adjusting water activity, adjusting pH, and/or using preservatives. However,
these
methods are generally expensive and therefore increase the cost of storing and
producing the foodstuff while, in some cases, diminishing the organoleptic
properties of
the food product.
SUMMARY
[0006] A high moisture preserved cheese product and a method of preserving a
high moisture cheese product is described herein. The high moisture preserved
cheese
product comprises a high moisture cheese and a preservative blend of: (i) at
least one
food grade organic food preserving acid or its food grade acceptable water
soluble salt
which can include citric acid and water soluble salts thereof and/or sorbic
acid and
water soluble salts thereof, (ii) a nisin component, (iii) and an enzyme
system which is
active against gram positive and gram negative bacteria as well as yeast and
molds,
and remains active to inhibit such bacterial in a pH range of 3.6 to 8.3. The
preservative
blend of organic preserving acid, nisin component and enzyme system is in an
amount
and the ingredients of such blend are in relative amounts to provide a high
moisture
preserved cheese product with less than 1 log cfu/g of pathogenic gram
positive and
gram negative bacteria for at least about 7 days when stored immediately after
its
production at 55 F, and preferably 45 F. In another aspect, the preserved
cheese
product is aseptically packaged immediately or nearly immediately after its
production
and the aseptically packaged preserved cheese product will have less than 1109
cfu/g
for at least 7 days if the aseptic package is opened just after packaging and
stored at
55 F, preferably 45 F. The preserved cheese product exhibits organoleptic
properties
similar to the same non-preserved cheese for at least 7 days after its
production and
storage which is open to the atmosphere and is at 55 F, preferably 45 F. The
animal
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and fungal enzyme is commercially available as a blend under the name of Sea-i
from
BIENCA S.A, Avenue Reine Astrid 262, Seneffe 7180, Belgium. The method for
preserving the high moisture cheese product, includes mixing the preservative
blend of
the at least one organic food preserving acid which can include citric acid
and/or sorbic
acid, a nisin component, an enzyme system into curd which is a precursor to
the high
moisture cheese product. As with the preserved cheese product aspect of the
invention, in the method described herein, the preservative blend of organic
preserving
acid, nisin component and enzyme system is in an amount and the ingredients
are in
relative amounts effective to provide the high moisture preserved cheese
product with
less than 1 log cfu/g of pathogenic gram positive and gram negative bacteria
when
stored for at least about 7 days at 55 F, and preferably 45 F, with the
preserved cheese
product exhibiting organoleptic properties similar to the same high moisture
cheeses.
As described herein a "high moisture cheese product" has a moisture content of
at least
about 40 weight percent water. Additionally, aseptically packaged means
packaged to
the exclusion of microorganisms other than those carried by the packaged
product,
such as the preserved cheese product.
[0007] In one important aspect the food preserving acid is a blend of citric
acid and
sorbic acid. In an important aspect the blend of citric and sorbic acid is
combined with
the enzymes and nisin component such that the blend has 500 parts by weight,
based
upon the weight of the blend, sorbic acid, 900 parts by weight, based upon the
weight of
the blend, citric acid, 210 parts by weight, based upon the weight of the
blend, nisin, 12
parts by weight, based upon the weight of the blend, enzyme system.
[0008] In yet another important aspect, sorbic acid or its water soluble salt
comprises about 0.1 weight percent, based upon the dry solids of a fresh
cheese curd
which is a precursor of the fresh cheese, citric acid or its water soluble
salt comprises
0.18 weight percent, based upon dry solids of the cheese curd, nisin comprises
about
0.0042 weight percent, based upon dry solids of the cheese curd, enzyme system
comprises 0.00024 weight percent, based upon the dry solids of the cheese
curd.
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DETAILED DESCRIPTION
[0009] The high moisture preserved cheese product described herein has and
enhanced microbial food safety such that the combination of an organic acid,
nisin and
enzyme system provide a preserved cheese product that retains the taste and
organoleptic properties of the same cheese that does not have the combination
of acid,
nisin and enzyme system, but will provide a product with less gram positive
and gram
negative bacteria as described herein than the same cheese preserved with the
same
weight percents of food preservative acids, nisin and where weight percent of
the
enzyme system is replaced by sorbic (e.g. replacing enzyme system) and citric
acid
(replacing enzyme system).
[0010] The method described herein may be used in the production of any high
moisture, cultured dairy product, such as, but not limited to, fresh Mexican
cheeses,
such as queso fresco, mozzarella cheese, ricotta cheese and cottage cheese.
The
cheeses produced by the methods described herein advantageously enjoy
microbiological safety after removal of the preserved cheese from its
packaging,
rendering the cheeses more microbiologically stable over a longer period of
time.
[0011] Queso fresco or queso blanco is a creamy, soft, and mild unaged white
cheese. The name queso blanco is Spanish for "white cheese", but similar
cheeses are
used and known throughout the world by different names. Queso blanco is a
fresh and
slightly salty cow's milk cheese (which salts can include CaCl2, whereas queso
fresco
may be made from a combination of cow's and goat's milk. Both of these cheeses
will
be referred to herein as queso fresco cheese.
[0012] Queso fresco cheese is made by pressing the whey from rennet coagulated
cheese curd. Queso fresco generally has a high water activity of over 0.89 and
a high
pH ranging from about 5.25 to over 6Ø A typical queso fresco cheese has a
good melt
restriction. That is, when the cheese is exposed to moderate heat treatment
such as
boiling or microwave for a short period of time, it should remain in good
shape and not
melted unlike most other cheese products. Queso fresco, like other high
moisture, fresh
cheeses, if contaminated, will support growth of microbial contaminants in a
matter of
days without the addition of preservatives. Specifically, because of its
relatively high
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pH, queso fresco is susceptible to the growth of bacterial pathogens such as
Gram-
positive bacteria, including Listeria monocyto genes and Clostridium botulinum
as well
as Gram-negative bacteria such as Escherichia coil 0157:H7 and Salmonella. In
order
to be considered microbiologically stable, the cheese should not allow the
inoculated
pathogenic bacteria to grow more than 1 log in cfu/g in at least one month
under
refrigerated conditions. Most commercial queso fresco products on the market
today do
not meet these criteria.
[0013] Generally, the high moisture dairy products described herein retain
desirable
organoleptic qualities while having inhibiting bacterial growth by virtue of
blend of at
least one organic food preserving acid which can include citric acid and/or
sorbic acid, a
nisin component and an enzyme system. For example most currently commercially
available queso fresco cheese products have a shelf life (not more than 1 log
cfu/g) of
not more than three days when stored at about 45 F, as compared to queso
fresco
cheese products preserved by the blend as described herein.
[0014] The bacteriocin nisin is produced by fermentation using the bacterium
Lactococcus lactis. Commercially it is obtained from natural substrates
including milk
and is not chemically synthesized. It is used in processed cheese production
to extend
the safe, usable life by suppressing gram-positive spoilage and pathogenic
bacteria.
Due to its highly selective spectrum of activity it is also employed as a
selective agent in
microbiological media for the isolation of gram-negative bacteria, yeast and
molds. Two
commercially available antimicrobials containing nisin are Nisalpin and
Novasinim (both
from Daniso A/S, Denmark). Typically, Nisaplin contains less than about 3.0
weight %
nisin, the remainder consisting of NaCl, proteins, carbohydrates and moisture.
When
referring to a nisin component herein the component not only includes nisin,
but also
other ingredients which include carriers, salts, protein and carbohydrates.
[0015] Nisin is an inhibitory polycyclic peptide with 34 amino acid residues
used as
a food preservative. It contains the uncommon amino acids lanthionine,
methyllanthionine, dehydroalanine and dehydro-amino-butyric acid. These amino
acids
are synthesized by posttranslational modifications. In these reactions a
ribosomally
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synthesized 57-mer is converted to the final peptide. The unsaturated amino
acids
originate from serine and threonine.
[0016] Sorbic acid is a preservative used to inhibit molds, yeast and fungi
in many
foods and beverages. Generally, water soluble food grade salts of sorbic acid
are
preferred for their water solubility.
[0017] Citric acid is a weak acid and preservative. Food grade citric acid
and its
water soluble salts may be used as a part of the preserved cheese product and
method
described herein and is recognized as a safe food additive.
[0018] Sea-i is an enzyme system sold by BIENCA S.A., Belgium. Sea-i has a
range of activity to inhibit both Gram positive and Gram negative bacteria, in
addition to
yeasts and molds. Further, the enzyme system Sea-i is activated when
hydrated, with
at least 20% free moisture, in the system in which it is used. Sea-i is
deactivated by
heat (in excess of 50C), pH (active in the range of 3.6 to 8.3), sanitizers
(in particular
oxidizing agents) or over the passage of time. Upon deactivation Sea-i
becomes
protein with no catalytic activity.
[0019] Sea-i inhibits metabolite production and has either a bacteriostatic
effect
(by extending the latency phase) or bactericidal effect (killing micro-
organisms)
depending on the initial contamination.
[0020] The blend of organic food acid, nisin and enzyme system may be added
individually or premixed and blended into the cheese making process, such as
blending
the acids, nisin and enzyme system into the curd precursor having at least 20
weight
percent moisture to the cheese product to provide a homogeneous mixture of
blend and
curd. In a preferred embodiment, the preservative blend is blended with the
curd after
the separation of the whey in order to minimize loss of the components of the
preservative blend. Following the blending of the acid, nisin, enzyme system
with the
curd, the curd and preservative blend are mixed so that the preservative blend
is
homogenously dispersed throughout the curd. Generally this mixing takes from
about 8
to about 10 minutes.
[0021] Advantageously, although the preserved cheese product described herein
remains microbiologically stable longer after opening or exposure to
microbiological
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contaminants, the cheese does not suffer from adverse organoleptic properties.
For
example, in conventional queso fresco cheese, it is desirable to prevent post-
process
acidification. If post-process acidification occurs, the acid produced by
natural
microflora during storage will result in rapid acidification of the cheese and
the
characteristic crumbly texture and melt restriction properties are lost and an
undesirable
fermented flavor will develop. By using the methods described herein, risk of
post-
process acidification is mitigated or eliminated by using a blend which
includes citric
acid, sorbic acid, nisin and an enzyme system such as Sea-i . Thus, the
methods
described herein can be used to produce a preserved queso fresco cheese that
may be
safely stored for an extended period of time after opening without losing the
typical
physical and organoleptic characteristics of queso fresco cheese.
[0022] A better understanding of the present embodiment and its many
advantages
may be clarified with the following examples, given by way of illustration.
Comparative Example 1: Preparation of Control Queso Fresco Cheese.
[00231 A queso fresco cheese without enhanced microbial stability was prepared
as
described hereinbelow. No antimicrobial compounds were added.
1. Add CaCl2 (0.01% of 45% stock solution, diluted in deionized water) to milk
in
vat;
2. Slowly heat milk in vat with agitation ¨ target about 88 F (range of about
86 to
about 90 F);
3. Add the pre-made starter culture at 2%;
4. Hold 15 min with agitation;
5. Add rennet (0.01% of 2x Chymax, diluted in deionized water);
6. Hold 40 minutes with no agitation;
7. Cut curd and heal for 10 minutes ¨ no agitation;
8. Slowly heat curd and whey to about 106 F over about 20 min ¨ with
agitation;
9. Hold for 5 minutes with no heat and no agitation;
10. Pump curd and whey to drain table, stir and drain whey (curd pH 6.2-6.5);
11. Let stand for 5 minutes;
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12. Pack cheese into individual packages/casings; and
13. Refrigerate the cheese.
[0024] The resulting cheese had a moisture content of about 48% and a pH
of about
6.3. The queso fresco was then stored at 45 F for six weeks, during which time
the
queso fresco was analyzed for bacterial growth, in particular Listeria,
Salmonella and
E.Coli at 45 F and 55 F. Bacterial growth exceeding 1 log CFU / gram was
considered
a failed test.
Table 1: Bacterial Growth in Queso Fresco Control at 45 F
Interval (Day) Listeria Salmonella E.Coli
0 _*
1 Pass Pass Pass
3 Pass Pass Pass
Fail Pass Pass
7 Fail Pass Fail
Fail Pass Fail
14 Pass
21 Pass
24 Pass
28 Pass
35 Pass
42 Pass
* Indicates not tested.
Table 2: Bacterial Growth in Queso Fresco Control at 55 F
Interval (Day) Listeria Salmonella E.Coli
0 _*
1 Pass Pass Pass
3 Fail Fail Fail
5 Fail Fail Fail
42
* Indicates not tested.
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Example 2: Queso Fresco with the Addition of Sorbic Acid, Nisin and Sea-i
[0025] Queso fresco was prepared in the same manner as in Example 1.
However,
after step 10 wherein the whey is drained from the curd, a premixed
antimicrobial blend
was added to the curd. The antimicrobial blend included sorbic acid, Nisaplin
and Sea-
le. Further, the blend included 7 parts Nisaplin, 5 parts sorbic acid and 6
parts Sea-i .
The blend was added to the curd, and the curd and blend were mixed for about 8-
10
minutes to achieve a homogenous dispersion of the blend throughout the curd.
In
particular, the curd and blend combination included 0.07% Nisaplin, 0.05%
sorbic acid
and 0.06% Sea-i . As with Example 1, the queso fresco was stored at both 45 F
and
55 F for six weeks, during which time the queso fresco was analyzed for
bacterial
growth, in particular Listeria, Salmonella and E.Coli at 45 F and 55 F.
Bacterial growth
exceeding 1 log CFU / gram was considered a failed test.
Table 3: Bacterial Growth in Queso Fresco with Antimicrobial Combination at 45
F
Interval (Day) Listeria Salmonella E.Coli
0
1 Pass Pass Pass
3 Pass Pass Pass
Pass Pass Pass
7 Pass Pass Pass
Pass Pass Pass
14 Pass Pass Fail
* Indicates not tested.
Table 4: Bacterial Growth in Queso Fresco with Antimicrobial Combination at 55
F
Interval (Day) Listeria Salmonella E.Coli
0
1 Pass Pass Pass
3 Pass Pass Pass
5 Pass Pass Fail
7 Pass Pass Fail
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Pass Fail
14 Pass Fail
* Indicates not tested.
Example 3: Queso Freso with the Addition of Citric Acid, Sorbic Acid, Nisin
and Sea-i0
[0026] Queso fresco was processed using the procedures of Example 2, but with
the addition of citric acid. The relative amounts of sorbic acid, Nisaplin and
Sea-ie
remained the same as in Example 2. Further, the overall percentage of sorbic
acid and
Nisaplin in the curd / blend combination remained unchanged. The blend
included 7
parts Nisaplin, 5 parts sorbic acid, 6 parts Sea-Ks and 9 parts citric acid.
The blend was
added to the curd, and the curd and blend were mixed for about 8-10 minutes to
achieve a homogenous dispersion of the blend throughout the curd. In
particular, the
curd and blend combination included 0.07% Nisaplin, 0.05% sorbic acid, 0.06%
Sea-is
and 0.09% citric acid. As with Example 1, the queso fresco was stored at 45 F
for six
weeks, during which time the queso fresco was analyzed for bacterial growth,
in
particular Listeria, Salmonella and E.Coli at 45 F and 55 F. Bacterial growth
exceeding
1109 CFU / gram was considered a failed test.
Table 5: Bacterial Growth in Queso Fresco with Antimicrobial Combination at 45
F
Interval (Day) Listeria Salmonella E.Coli
1 Pass Pass Pass
3 Pass Pass Pass
5 Pass Pass Pass
7 Pass Pass Pass
10 Pass Pass Pass
14 Pass Pass
* Indicates not tested.
Table 6: Bacterial Growth in Queso Fresco with Antimicrobial Combination at 55
F
Interval (Day) Listeria Salmonella E.Coli
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0
1 Pass Pass Pass
3 Pass Pass Pass
Pass Pass Pass
7 Pass Pass Pass
Pass Pass Pass
14 Pass Pass Pass
* Indicates not tested.
Example 4: Queso Fresco with the Addition of Citric Acid, Sorbic Acid, Nisin,
Sea-i
and an "Activated Culture"
[0027] Queso fresco was processed using the procedures of Example 3, but an
"activated culture" was added to the antimicrobial combination. In particular,
the
"activated culture" is a low acid, nisin producing culture as described in
U.S. Patent
Publication No. 2008/0152757. The relative amounts of each component of the
blend
included 7 parts Nisaplin, 5 parts sorbic acid, 6 parts Sea-i , 9 parts citric
acid and 1
part activated culture. Within the curd and blend combination, the Nisaplin
comprised
0.07%, sorbic acid comprised 0.05%, Sea-i comprised 0,06%, citric acid
comprised
0.09% and the activated culture comprised 0.01%.
Table 7: Bacterial Growth in Queso Fresco with Antimicrobial Combination at 45
F
Interval (Day) Listeria Salmonella E.Coli
0
1 Pass Pass Pass
3 Pass Pass Pass
5 Pass Pass Pass
7 Pass Pass Pass
10 Pass Pass Pass
14 Pass Pass Pass
* Indicates not tested.
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Table 8: Bacterial Growth in Queso Fresco with Antimicrobial Combination at 55
F
Interval (Day) Listeria
Salmonella
E.Coli
0
1 Pass
Pass
Pass
3 Pass
Pass
Pass
5 Pass
Pass
Pass
7 Pass
Pass
Pass
10 Pass
Pass
Pass
14 Pass
Pass
Pass
* indicates not tested.
Example 5: Microbial Stability of Queso Fresco at Refrigeration Temperature.
[0028] The microbial stability of the inventive cheese
from Example 3 above was
compared to the cheeses of Examples 2 and 4 under refrigeration conditions.
Two
pathogens capable of growing under refrigeration conditions were used. The
psychrotrophic pathogens included both Gram-positive (Listeria monocytogenes)
and
Gram-negative bacteria (Escherichia coh).
[0029] The inventive cheese sample of Example 3 and the
cheeses of Examples 2
and 4 were inoculated with L. monocytogenes and E. coil and were stored at 45
F for a
period of 5 weeks. The results of the growth of L. monocytogenes and E. coli
in the
cheeses at 45 F are summarized in Tables 9 and 10 below.
Table 9. Average Growth of L. monocytogenes in Queso Fresco cheese during
storage at 45 F
Treatment 0
3 5 Time (days)
7 14
Example 3 , 20
10 , <10
<10 <10
Example 2 <10
<10 <10
<10 <10
Example 4 <10
<10 <10
<10 <10
Values in the above table are reported in colony forming units (cfu) per gram
of cheese.
[0030] The data shows that the blends of Examples 2, 3
and 4 effectively inhibited
the growth of Listeria monocytogenes at refrigeration temperature.
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Table 10. Growth of E. coil in Queso Fresco cheese during storage at 45 F
Time (days)
Treatment 0 3 5 7 14 21 28 35
Example 2 56.7 10 <10 <10 <10 <10 <10
Example 3 110 <10 170 <10 <10 <10
Example 4 <15 <100 <10 <110 <10 <10 <10
Values in the above table are reported in colony forming units (cfu) per gram
of cheese.
[0031] The data shows that the blends of Examples 2, 3 and 4 effectively
inhibited
the growth of E. coli at a refrigeration temperature of 45 degrees Fahrenheit.
Example 6: Microbial Stability of Queso Fresco at Abused Temperature.
[0032] The microbial stability of the inventive cheese from Example 3 above
was
compared to the cheeses of Examples 2 and 4 at a slightly abused temperature
(55 F).
The cheeses of Examples 2, 3 and 4 were inoculated with L. monocytogenes and
E. coil
and was stored at 55 F for a period of 5 weeks. Samples were taken for L.
monocytogenes and E. coli analysis periodically. The results are shown in
Tables 11
and 12 below.
Table 11. Growth of L. monocytogenes in Queso Fresco cheese during storage at
55 F
Time (days)
Treatment 0 3 5 7 14 21 28 35
Example 2 20 <10 <10 1766.7 349066
Example 3 <10 <10 <10 <10 9050 165275 708000
Example 4 <10 - <10 <10 <10 <7285 5093 <13030
Values in the above table are reported in colony forming units (cfu) per gram
of cheese.
[0033] The data shows that the cheese of Example 2 supported a rapid growth
of L.
monocytogenes noticeable on day 7 while the cheeses of Examples 3 and 4
effectively
inhibited the growth of Listeria monocytogenes at 55 F at least through seven
days.
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Table 12. Growth of E. coil in Queso Fresco cheese during storage at 55 F
Time 'days)
Treatment 0 3 5 7 14 21 28 35
Example 2 56.7 30 50 606.7 6240
Example 3 110 35 <10 <15 <40 <2600 <3400 <850
Example 4 <15 <10 <10 <1 <500 <4800 <10 <130
Values in the above table are reported in colony forming units (cfu) per gram
of cheese.
[0034] The data shows that the cheese of Example 2 supported a rapid growth
of E.
coil noticeable on day 7 while the cheeses of Examples 3 and 4 effectively
inhibited the
growth of E. coil at 55 F at least through seven days.
Example 7: Sensory evaluation of the traditional Queso Fresco and Formulations
of
Examples 2, 3 and 4:
[0035] A formal consumer evaluation was performed in areas with a relatively
larger
population of Mexican Americans. The products were evaluated in several
categories
including general rating, purchase intent, flavor, texture, melting and
appearance. The
assessment results are shown in Table 13.
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Table 13. Consumer sensory evaluation scores of Queso Fresco cheese
Category
Control Example 2
Example 3 Example 4
(no antimicrobial)
_
General ratings:
(
_ Overall opinion of Appearance (9 pt) _
7.23/7.86
7.61/7.77 7.42/7.82
7.53/7.82
Overall opinion (9 pt.)
7.08/7.57
7.19/7.17 _ 7.24/7.56
7.27/7.20
Expectation ("better or same" %)
82/96
93/87 _ 88/95
83/91
Flavor: Purchase intent (5 pt.)
3.86/3.8 1
3.96/3.39 3.97/3.62
4.01/3.55 -
Overall flavor liking (9 pt.)
6.91/7.52
7.08/7.11 7.24/7.45
7.16/7.3
Flavor strength ("just right" %)
53/92 ,
42/81 56/88
_ 56/83
Milky/dairy (lust right" %)
52/95
55/85 55/87
49/89
Saltiness ("just right" %)
64/93
54/71 68/84
68/79
Sourness ("just right" %)
62/95 .
66/92 -1 71/90
65/89 _
After taste ("moderate" %)
69/9
75/17 82/15
60/16
Pleasantness after taste (%)
77/86
86/47 86/71
77/86
Texture/Melting:
_ {
Overall texture liking (9 pt.)
7.09/7.58
7.23/6.98 7.19/7.43
7.14/7.41
Crumbliness liking (9 pt.)
7.22/7.59
7.17/7.05 7.36/7.55
7.25/7.34
Melting liking (9 pt.)
6.96/7.2
7.01/6.69 7.02/7.07
7.03/7.19
Cutting liking (9 pt.)
6.99/7.38 _
7.12/6.92 7.06/7.82
6.97/7.21
Firmness as Cutting ("just right" %)
31/86
24/74 7/79
28/83 _
Creaminess (just right" %)
49/90
33/80 43/81
42/84
Firmness (lust right" %)
52/86
38/78 39/89
41/85
Smoothness (lust right" %)
55/85
38/85 _ 50/83
47/87
Moistness liking (9 pt.)
60/90
48/83 49/82
50/86 .
Appearance:
1
Overall appearance liking (9 pt.)
7.1/7.67
7.22/7.36 7.39/7.55
7.38/7.54
Color (lust right" %)
69/95
70/95 , 60/96
62/92
Moist appearance (lust right" %)
59/94
55/80 50/83
59/94
The results are shown based on the scores from Los Angeles / Houston
[0036] The consumer evaluation results suggest
that the cheese of Example 3 was
at parity to the control (traditionally made base cheese without any
inhibitors). The
cheese of Example 3 did not significantly change the overall quality profiles
of the
cheese, nor impact consumer acceptance of the cheese. Further, the cheese of
Example 3 provided superior ratings over the cheeses of Examples 2 and 4.
Example 8: Alternative Combinations Reviewed
[0037] Alternative combinations were prepared and
reviewed for organoleptic
qualities and bacterial growth, in particular Listeria, Salmonella and E.coli.
Each
combination was tested under two different temperature conditions: 45 F and 55
F.
Although some of the alternative combinations tested did inhibit bacterial
growth over a
long period of time after package opening, the organoleptic qualities of the
combinations
along with the bacterial resistance was unacceptable. In assessing the
bacterial
growth, the presence of a bacterium of 1 log CFU was considered a failed test.
15
CA 02684721 2009-11-05
Table 14: Combination of Nisaplin, Sorbic Acid, Sea-i and Pediocin at 45 F
Interval (Day) Listeria Salmonella E.Coli
0 * * *
1 Pass Pass Pass
3 Pass Pass Pass
Pass Pass Pass
7 Pass Pass , Pass
Pass Pass Pass
14 Pass Pass Fail
21 Pass Pass Fail
24 Pass Pass *
28 Pass Pass *
35 Pass Pass *
42 Pass Pass *
49 Pass , Pass *
56 Pass Pass *
70 Pass Pass *
84 _ Pass Pass *
98 Pass Pass *
* Indicates not tested.
Table 15: Combination of Nisaplin, Sorbic Acid, Sea-i and Pediocin at 55 F
Interval (Day) Listeria , Salmonella E.Coli .
0 * * *
1 Pass Pass Pass
3 Pass _ Pass Pass
5 _ Pass _ Pass Pass
7 Pass Pass Fail
10 Pass Fail Fail
14 Pass Fail *
21 Pass * *
24 Fail * *
28 Fail _ * *
-
16
CA 02684721 2009-11-05
35 Fail *
*
* Indicates not tested.
Table 16: Combination of Nisaplin, Sorbic Acid, Sea-i and a Low Acid, Nisin
Producing Culture at 45 F
Interval (Day) Listeria Salmonella
E.Coli
_
0 * *
*
1 Pass Pass
Pass
3 Pass Pass _
Pass
Pass Pass Pass
7 Pass Pass
Pass
Pass Pass Pass
14 Pass Pass
Pass
21 Pass Pass
Pass
24 Pass Pass
Pass
28 , Pass Pass
Pass
35 Pass Pass
Pass
42 Pass Pass
Pass
49 Pass Pass
Pass
56 Pass Pass
Pass
70 Pass Pass
Pass
84 Pass Pass
Pass
98 Pass Pass
Pass
* Indicates not tested.
Table 17: Combination of Nisaplin, Sorbic Acid, Sea-le and a Low Acid, Nisin
Producing Culture at 55 F
Interval (Day) Listeria Salmonella
E.Coli
0 *
*
1 Pass Pass
Pass
3 Pass Pass
Pass
5 Pass Pass
Pass
_
7 Pass Pass
Pass
10 Pass Pass
Pass
_
14 Pass Pass
Pass
21 Pass Pass
Pass
17
CA 02684721 2009-11-05
24 Pass Pass Pass
28 Pass Pass Pass
35 Pass Pass Pass
42 Pass Pass Pass
49 Pass Pass Pass
56 Pass Pass Pass
70 Pass Pass Pass
84 Pass Pass Pass
98 Pass Pass Pass
* Indicates not tested.
Table 18: Combination of Nisaplin, Sorbic Acid, Sea-i and AM1079 at 45 F
Interval (Day) Listeria Salmonella E.Coli
0
1 Pass Pass Pass
3 Pass Pass Pass
Pass Pass Pass
7 Pass Pass Pass
Pass Pass Pass
14 Pass Pass Pass
21 Pass Pass Pass
24 Pass Pass Pass
28 Pass Pass Pass
35 Pass Pass Pass
42 Pass Pass Pass
49 Pass Pass Pass
56 Pass Pass Pass
70 Pass Pass Pass
84 Pass Pass Pass
98 Pass Pass Pass
* Indicates not tested.
Table 19: Combination of Nisaplin, Sorbic Acid, Sea-i and AM1079 at 55 F
interval (Day) Listeria Salmonella E.Coli
18
CA 02684721 2012-07-27
0 * * *
1 Pass Pass Pass -
3 Pass Pass Pass
Pass Pass Pass
7 Pass Pass _ Pass
Pass Pass Pass
14 Pass Pass Pass
_
21 Pass Pass Pass
24 Pass Pass Pass
28 Pass Pass Pass
35 Pass Pass Pass -
_
42 Pass Pass Pass
49 Pass Pass Pass -
56 Pass Pass Pass
70 Pass Pass Pass
84 Pass Pass _ Pass
98 Pass Pass Pass
_
* Indicates not tested.
[0038] All percentages throughout this specification are by weight percent
unless
otherwise specified.
19
