الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Mushrooms have been considered a delicious [001 for
several thousand years. The early history of mushroom culti .ation
is shrouded in antiquity. This study was carried out for:
1- Studying the possibility of producing canned mushrooms and
determine its acceptability among consumers.
2- Studying heat penetration of canned mushrooms.
3- Studying the optimum thermal process time.
The results can be summarized as follow:
• The obtained results indicate that washing did not cause any
major detectable changes in the chemical constituents of
mushroom (Agaricus bisporus). However slight change was
observed in the main constituents after hlanching.
Carbohydrate, protein, ether extract and ash were slightly
decreased. where minor increase was noticed in the crude
fibers. After processing the same previously described pattern
was still observed in the main constituents as moisture and
crude fiber increased while protein and total carbohydrate
decreased.
• The results indicated that the same pattern was obtained for the
chemical constituents of oyster mushroom (Pleurotus
ostreatus), since washing had almost always no effect on
chemical constituents. But the blanching process induced a
slight increase in moisture content and a moderate decrements
in total protein, ether extract, carbohydrate and ash. However
an apparent increase was also observed for crude fiber. Thermal
treatment positively effected both the decrement and/or
increment values of the different constituents.
• Organoleptic evaluation cleared that there were significant
differences between fresh, blanched and/or canned mushroom.
Generally, in most cases scores that had given to processed A.
77
bisporus were higher in most cases than that given to.canned
P. ostreatus.
• Higher the total bacterial count was 6.45xl0
1 and 8.96xl0
1
for
fresh A. bisporus and P. ostreatus, respectively.These counl~
tended to decrease after washini and continued to dectla’l6
obviously after blanching (9.5xIO and l.OOxlOS: respectivl!tyY.
However, the total bacterial counts were recovered in 1lt~.
quantities which represented 14 and 15 microorganisms per
1-00 gram for samples of Agaricus bisporus and Pleurotus
ostreatus thermal treated at 230.9°F (11O.SOC), respectively. As
for spore-forming bacteria the same trend was observed. Since
the spore forming bacteria recovered from samples thermal
treated at 230.9°F (110.5°C) for Agaricus bisporus and
P!eurolus ostreatlls were 9 and 11 per 1·00 gram, respectively.
During storage for 12 months microbial counts anc spore
forming bacteria decreased at different rates.
• Results indicated that the percent decrements in total tacterial
counts of canned Agaricus bisporus and Pleurotus 0. itreatus
thermal treated at 230.9°P (lIG.5°C) were 21.430/0 and 6.670/0,
respectively. While the corresponding values for spore forming
bacteria were 22.22% and 18.18%, respectively.