Biomedical Engineering Reference
In-Depth Information
Other Meats
Radiation treatment of lamb, which serves as a principal meat source in various
countries including India and Greece, was reported by Paul et al.
182
The study
concluded that radiation with 1 and 2.5 kGy extended the shelf life of minced lamb
an additional 1 and 3 weeks, respectively, over the control when stored at 0 to 3°C.
Chunk lamb, which was similarly treated, exhibited an enhanced shelf life of 2 and
4 weeks, respectively, over the control. Both the chunk and mince control samples
appeared greenish and slimy within a week and contained an aerobic plate count of
10
7
and 10
8
cfu/g, respectively. In contrast, samples that were initially radiated did
not exhibit these characteristics during spoilage, primarily due to the elimination of
Pseudomonas
. Irradiation odors, which were not detected in any of the treated
samples by a sensory panel, have previously been reported to occur with dosages
only greater than 6.25 kGy.
57
Interestingly, venison was reported to have a similar
threshold dose.
57
In order to mimic conditions likely to occur during transportation and retail
display, especially in rural India, Naik et al.
183
maintained freshly packaged buffalo
meat at ambient temperatures of 28 to 30°C following slaughter. Under these con-
ditions, a shelf life of approximately 18 h was realized. Following irradiation at
2.5 kGy the shelf life, based on bacteriological, sensory, and chemical analyses, was
extended to 42 h.
Consumed to a lesser extent but still economically important, the shelf life of
refrigerated red or edible offal including tripe (first and second bovine stomach) and
lamb liver was also demonstrated to improve after radiation.
150
Vacuum-packaged, sliced corned beef normally has a shelf life from 2 to 3 weeks
when maintained at 5°C. Spoilage normally coincides with bacterial counts of
it was demonstrated that a dose of 2 kGy was sufficient to double the shelf life of
the product at 5°C, based on taste panel ratings of flavor, aroma, and bacterial plate
TABLE 3.4
Shelf Life Extension of Vacuum-Packaged Sliced Corned Beef Maintained
at 5°C Following Radiation Treatment
Log
10
Units
Reduction in
Initial Population
Time for Population
to Reach 10
8
cfu/g
(weeks)
a
Radiation Dose
(kGy)
Major Spoilage
Microorganisms
0
—
2
Lactic acid bacteria
1
1
3
Lactic acid bacteria
2
2-2.5
4-5
Brochothrix thermosphacta
4
>4
>7
Gram-negative bacteria
Point of visible spoilage.
a
Adapted from Wills et al.
184
Search WWH ::
Custom Search