الفهرس 
I. Hard/Ras cheeseOnly 14 pages are availabe for public view
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Abstract
Cheese, considered is one of the most important suppliers of biogenic amines (BA) , the low-molecular-weight organic bases that are
common constituents of many foods. It can be formed in fermented foods
such as cheese, wine, beer, sausages and fish products at higher levels
(100–1000 mg kg_1) however they may have unwanted health
consequences for consumers. Ras cheese is one of the popular hard cheeses in the Mediterranean
countries, particularly in the Middle and Near East. In Egypt, it is the
main traditional hard cheese and manufactured in a high proportion under
artisan conditions from raw cow’s or mixture of cow’s and buffalo’s milk
with using starter cultures 1.5% and marketed when it has a queried sharp
flavour closed to kefalotyic cheese after 3 to 6 months Cheese is represent one of the food could be subjected to deterioration
due to contamination, hydrolysis and oxidation of its components from
lipid (lipolysis) and protein (proteolysis) by enzymatic as well as microbial
reactions. Otherwise, fat of cheese becomes rancid as a consequence of
oxidation and oxidative rancidity takes place by autooxidation and
microorganisms. Recently, interest on the effect of malonaldehyde, one of
the major products of the oxidation of polyunsaturated fatty acids, on
human health has been reported by many authors that is mutagenic and
carcinogenic. Cheese is represent one of the food could be subjected to deterioration
due to contamination, hydrolysis and oxidation of its components from
lipid (lipolysis) and protein (proteolysis) by enzymatic as well as microbial
reactions. Otherwise, fat of cheese becomes rancid as a consequence of
oxidation and oxidative rancidity takes place by autooxidation and
microorganisms. Recently, interest on the effect of malonaldehyde, one of
the major products of the oxidation of polyunsaturated fatty acids, on
human health has been reported by many authors that is mutagenic and
carcinogenic. The mutagenicity of malonaldehyde has been demonstrated by the
Ames salmonella revertant procedure while its carcinogenicity was
observed on the skin of mice. Therefore, the fat quality (lipolysis) of hard cheese as affected by storage for 6 months at refrigerator (150C and 85%
humidity) in correlation with biogenic amines content will be in the scope
of this study. Also, microbiological parameters represent a good indicator of
keeping quality of different food items. The microbiological quality of
fresh and ripening cheese distributed in Egypt had been studied extensively
The present study was aimed to: 1. Determine the biogenic amines contents (mg/100 gm) of hard cheese
as affected by ripening for 6 months at refrigerator (150C and
humidity 85%). 2. Evaluate the microbiological quality of hard cheese as affected by
storage at room temperature at intervals in correlation with biogenic
amines formation 3. Investigate Correlation between different herbs used as thyme and
black seed toward microbiological parameters and biogenic amines
formation of hard cheese had studied . The obtained data could be summarized as follow: I. The affect of adding some herbs on the formation of biogenic amines
in hard cheese storage for six months The percent of recovery for all detected amines were ranged 61.16 to
93.76 %. The highest recovered amine was recorded for tryptamine while
the lowest one was spermidine. The eight detected amines could be ranged
with the recovery values as follow: tryptamine histamine
phenylethylamine cadaverine putrescine tyramine spermine
spermidine. Habbat Al-barakah powder (HAP) The total biogenic amines content of fresh hard cheese samples was
recorded 2.068 mg.100g-1 . The highest recovered amine was recorded for
tyramine while the lowest one was spermine . The average concentrations
of tyramine, phenylethylamine, histamine, putrescine, cadaverine,
spermidine and spermine were 0.121, 0.152, 0.119, 1.160, 0.160, 0.272,
0.048 and 0.036 mg.100g-1, respectively. After 6 months of storage at 150C
and 85% relative humidity, the average concentrations were increased by
the rates of 9.09, 4807.89, 329.41, 4175.86, 5843.75, 675.74, 443.75 and
711.11 % for all of these amines, respectively. By other meaning, the total
biogenic amines detected in cheese samples was increased by the ratio of
3278.92% as the result of storage for 6 months at 150C and 85% relative
humidity. The biogenic amine, tyramine, was constituted 70.98% of the
total amines content detected in both fresh and storage cheese samples. On
the other side, the same data indicated the effect of adding Habbat Albarakah
powder (HAP) on the formation rate of biogenic amines in hard cheese samples. It could be noticed that the adding of 250 mg.kg-1 of HAP
leads to decrease in the total content of biogenic amines by the ratio
21.57%. The average concentrations of tyramine, phenylethylamine,
histamine, putrescine, cadaverine, spermidine and spermine were decreased
by the rates of 13.53, 21.11, 23.85, 21.11, 24.16, 23.70, 17.28 and 14.26%,
respectively. With the increasing of HAP concentrations, all of these
amines were recorded and gradually decreased by different ratios
individually. The adding of 1000 mg.kg-1 of HAP leads to decrease in the
average concentrations of average concentrations of tyramine,
phenylethylamine, histamine, putrescine, cadaverine, spermidine and
spermine were decreased by the rates of 56.03, 48.32, 52.36, 48.45, 55.81,
51.77, 52.28 and 48.45%, respectively. So, the highest rate of decreasing
was recorded for tryptamine and the lowest one for phenylethylamine. Thyme powder (TP) The adding of 250 mg.kg-1 of TP leads to decrease in the total content
of biogenic amines by the ratio 13.70%. The average concentrations of
tyramine, phenylethylamine, histamine, putrescine, cadaverine, spermidine
and spermine were decreased by the rates of 9.09, 13.45, 16.21, 14.25,
12.46, 8.09, 10.42 and 7.40%, respectively. With the increasing of TP
concentrations, all of these amines were recorded and gradually decreased
by different ratios individually. The adding of 1000 mg.kg-1 of TP leads to
decrease in the average concentrations of average concentrations of
tyramine, phenylethylamine, histamine, putrescine, cadaverine, spermidine
and spermine were decreased by the rates of 36.14, 38.29, 40.05, 43.20,
36.14, 37.56, 43.80 and 60.11%, respectively. So, the highest rate of
decreasing was recorded for spermine and the lowest one for tryptamine
and putrescine. Habbat Al-barakah powder (HAP) plus Thyme powder (TP) The adding of 250 mg.kg-1 of HAP plus TP leads to decrease in the
total content of biogenic amines by the ratio 23.57%. The average
concentrations of tyramine, phenylethylamine, histamine, putrescine,
cadaverine, spermidine and spermine were decreased by the rates of 20.82,
32.03, 16.91, 23.21, 21.87, 11.34, 20.82 and 27.67%, respectively. With the
increasing of the mixture concentrations, all of these amines were recorded
and gradually decreased by different ratios individually. The adding of
1000 mg.kg-1 of HAP plus TP leads to decrease in the average
concentrations of average concentrations of tyramine, phenylethylamine,
histamine, putrescine, cadaverine, spermidine and spermine were decreased
by the rates of 48.32, 59.80, 51.99, 53.45, 55.90, 61.55, 55.90 and 59.33,
respectively. So, the highest rate of decreasing was recorded for cadaverine
and the lowest one for tryptamine and putrescine.
II. The effect of mixture Habbat Al-barakah (HA) plus Thyme powder TP) on microbial examination of hard cheese as affected by
storage for 6 months The total bacterial count (TBC), lactic acid bacteria (LAB) and
molds+yeasts (MY) of fresh hard cheese samples were recorded 1.4 x107,
0.7 x107 and 0.3 x104 cfu/ml, respectively. After 6 months of storage at
150C and 85% relative humidity, the average concentrations were increased
by the rates of 235.7, 171.4 and 5966.7% for all of these parameters,
respectively. On the other side, the same data indicated the effect of adding
HAP plus TP on the growing rate of bacterial groups in hard cheese
samples. It could be noticed that the adding of 250 mg.kg-1 of herbs
mixture leads to decrease in the total count of total bacterial count (TBC), lactic acid bacteria (LAB) and molds+yeasts (MY) by the ratios 12.8, 10.5
and 114.8%, respectively. With the increasing of herbal mixture
concentrations, all of these bacterial parameters were recorded and
gradually decreased by different ratios individually. The adding of 1000
mg.kg-1 of herbal mixture leads to decrease in the average count of total
bacterial count (TBC), lactic acid bacteria (LAB) and molds+yeasts (MY)
were decreased by the rates of 38.30, 47.37 and 46.15%, respectively III. Correlation analysis When all biogenic amines were included in the statistical analysis,
there was a negative significant (p<0.05 and p<0.01) relationship between
tested herbal concentrations [HAP (R2 = 0.709), TP (R2=0.625) and HAP
plus TP (R2= 0.739)]. The negative relationship between different
microbiological parameters and biogenic amines content in hard cheese
interpreted the potential effect of antioxidants in herbs, essential oils,
phenolics etc, on the formation pathways of BA in hard cheese In additional, important differences were found between different
microbiological parameters and biogenic amines content of hard cheese.
When all biogenic amines were included in the statistical analysis, there
was a positive significant (p<0.05 and p<0.01) relationship between tested
herbal concentrations [HAP (R2 = 0.871), TP (R2=440) and HAP plus TP
(R2= 0.875)]. The positive relationship between different microbiological
parameters and biogenic amines content in hard cheese interpreted the role
of different microbial species on the formation of BA in hard cheese.