الفهرس 
1. INTRODUCTION.Only 14 pages are availabe for public view
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Abstract
corporation of probiotics in plant flavored soft cheese:-
Domiati cheese is the most popular soft cheese in Egypt. It could be consumed fresh or after pickling (3-6) months. Cheese industry has been developed such as adding some plant flavors.
The main objective of this study was to investigate the possibility of making a good quality Domiati cheese by adding sweet and hot pepper extracts and incorporating bifidobacteria, therefore the effect of sweet and hot pepper on the viability of bifidobacteria was studied. The obtained results observed that bifidobacteria could tolerate 2 % of sweet and hot pepper extracts.
The second and third part of this study were to evaluate the effect of adding 2 % of sweet and hot pepper on the quality of the resultant cheese and the viability of bifidobacteria added to these cheese and monitor the change of cheese quality during the pickling period. The obtained results indicated that the most acceptable cheese was made by adding 2 % peppers extract and incorporating bifidobacteria.
The obtained results can be summarized as follows:-
1. Titratable acidity :-
Titratable acidity of all cheese treatments increased throughout the pickling period. All sweet pepper extract and non-flavored treatments except T1 were higher than the control. (T1, T3 and T5) of the hot pepper extract treatments were lower than the control
cheese. The titratable acidity of hot pepper extract flavored Domiati cheese (T3 and T5) were lower than the control obverse the same treatment with sweet pepper extract (T3 and T5) which higher than the control cheese, this may be due to the different effect of capsaicin in hot pepper extract compared to sweet pepper extract.
2. Moisture content :-
Moisture content of all cheese treatments gradually decreased at all the pickling period. The cheese treatment with sweet pepper extract (SPE) showed higher moisture content than the cheese treatments with hot pepper extract (HPE) at any stage of pickling period. T1 was the highest moisture content in the sweet pepper extract flavored cheese, and the other treatments were lower than the control cheese. The hot pepper extract flavored cheese contains higher moisture content than the control cheese along the pickling period.
3. pH value :-
The pH values of all cheese treatments decreased throughout the pickling period. The control and the pepper extract flavored and non-flavored cheese behaved similarly during the pickling period. T1 was generally higher than the other treatments of the SPE and HPE flavored cheese during the period of pickling.
4. Ash content :-
Ash content of all the sweet and hot pepper extracts flavored treatments and non-flavored treatments increased slightly as pickling
period progressed. Sweet and hot pepper extracts did not effect on the ash content of cheese treatments.
5. Fat content :-
Fat contents increased in all cheese treatments during the pickling period. The sweet pepper extract flavored and non-flavored treatments ((T2, T3, T4 and T5) except (T1)) shows a higher fat percent than control cheese. While, the control cheese of hot pepper extract flavored cheese showed a higher fat percent than HPE flavored Domiati cheese (T1, T3 and T5) and lower than (T2 and T4) at any stage of pickling period.
6. Total volatile fatty acids content (TVFA) :-
Total volatile fatty acids contents increased in all sweet and hot pepper extracts flavored and non-flavored cheese during the pickling period. The total volatile fatty acids content of sweet pepper extract flavored cheese (T1) was higher than the other treatments. While, the total volatile fatty acids content of (T2) was higher than the other hot pepper extract flavored and non-flavored treatments at any stage of pickling period.
7. Total nitrogen contents :-
Total nitrogen content of all cheese treatments decreased markedly during the first 4 weeks then it decreased gradually up to the end of pickling period; this decrease was probably due to the protein degradation during the pickling and the formation of water soluble compounds, which were lost in the pickling solution. The
control cheese of sweet pepper extract flavored Domiati cheese was higher than (T1) but lower than the other treatments; while (T1, T3 and T5) of hot pepper extract flavored Domiati cheese were higher total nitrogen content than control cheese and the other treatments.
8. Water soluble nitrogen content (WSN) :-
Water soluble nitrogen content of sweet and hot pepper extracts flavored cheese and control increased throughout the pickling period. Soluble nitrogen content of all treatments increased markedly during the first 4 weeks of pickling period then increased gradually up to the end of pickling period (12 week) as a result of protein degradation. The soluble nitrogen content of SPE flavored Domiati cheese (T1) was higher than the other treatments; while the soluble nitrogen content of the HPE flavored Domiati cheese (T1, T3 and T5) was lower than in the control.
9. The total bacterial counts :-
The bacterial counts of all treatments and control increased during the first 4 weeks then markedly decreased until the end of pickling period. The counts of all treatments (hot pepper extract (HPE) flavored Domiati cheese and sweet pepper flavored (SPE)) behaved the same trend. However, the counts of HPE flavored Domiati cheese were lower than it on SPE flavored Domiati cheese.
10. Bifidobacteria counts :-
The bifidobacteria counts increased during the first 4 weeks then it decreased till the end of pickling period. T2 and T4 in SPE
and HPE flavored cheese were higher counts than T3 and T5 which obtained the pepper extracts. The counts on HPE flavored cheese were lower than it on SPE flavored cheese.
11. Yeasts and molds count :-
The yeasts and molds count decreased or disappeared completely until the end of pickling period. The sweet and hot pepper extracts flavored and non-flavored cheese was lower than control of counts of yeasts and molds at any stage of pickling period. The counts on HPE flavored cheese were lower than it on SPE flavored cheese.
12. Organoleptic properties :-
The organoleptic properties of all treatments of sweet and hot pepper extracts flavored and non-flavored cheese and control increased throughout the pickling period. The highest total score relatively was found in T1, T3 and T5 on the sweet pepper extract flavored Domiati cheese, and the highest total score relatively was found in C, T3 and T5 on the hot pepper extract flavored Domiati cheese.
In finally, the study showed that incorporation probiotics in sweet and hot pepper extracts flavored cheese gave positive results. The counts of bifidobacteria stilled above the required counts, also both the chemical, microbial and organoleptic properties of product cheese were a good and a healthy dairy product.