| |
|
10.4.3.6 |
Keep
three petri dishes (as clause 10.4.3.5) in the incubator
at 35°C- 37°C for 24 + 2 hours. In case of no colony
occurs, incubate thpetri dishes for another 24 hours. |
| |
|
10.4.3.7 |
The colony occurred
from Salmonella on brilliant green, sulfadiazine
agar, shall help link to dark red or colourless,
translucent or opaque. The colony occurred from
salmonella shigella agar shall be pale pink or colourless,
translucent or opague or black in the middle. The
colony occured from bismuth sulphite agar shall
be black to black brown usually accompanied with
metallic sheen or sometimes green. Fish the-, colonies
suspected to be Salmonella on brilliant green sulfadiazine
agar, Salmonella shigella and bismuth sulphite agar
then inocubate the culture into triple sugar iron
agar slants and lysine iron agar slants, making
both a streak and stab inoculation. |
| |
|
10.4.3.8 |
Keep the 2 test
tubes in incubator at 35°- 37°C for 2.4 ±2 hours. |
| |
|
10.4.3.9 |
The
Salmonella occurred cm. triple sugar iron agar slants
shall be red on the surface and yellow at the bottom
of the test tube perhaps with black colour occurred
from hydrogensulphide. |
| |
|
10.4.3.10
|
The Salmonella
occurred on lysine iron agar slants shall be violet
both can the surface and at the bottom of the test
tube accompanied with black colour occurred from
hydrogensulphide. Fish the lysine iron agar slant
then streak and stab into triple sugar iron agar
slant. Keep the test tube in incubator at 35°- 37°C
for 24 ± 2 hours. Note the confirm test. |
| |
|
10.4.4
Test method for coliform |
| |
|
10.4.4.1 |
Pipette 1 cm3 of each subjected sample of clause
10.4.3.2 to three petri dishes. |
| |
|
10.4.4.2 |
Pour 15-20 cm3 of violet red bile agar to each petri
dish, mix thoroughly and then allow to solidify.
|
| |
|
10.4.4.3 |
Repour 3-4 cm3 of violet red bile agar into each
petri dish and allow to solidify again, invert the
petri dishes and incubate at 37 ± 1°C for 18-24
hours. |
| |
|
10.4.4.4 |
In case of using, the violet red bile agar, the
coliform shall give the opague red violet colony
of at least 0.5 mm in diameter and shall also give
reddish zone of precipitated bile. The number of
coliform occurred shall be not more than 1. |
| |
|
10.4.4.5 |
In case of using the desoxy cholate agar the coliform
shall give red colony. Remark. The reagent, agar
and apparatus shall be pasteurized before use. |
| |
10.5 |
Moisture
content
10.5.1 Apparatus
10.5.1.1 Weighing balance: having a
readability of 4 significant figures:
10.5.1.2 Aluminum container of 41.5
cm in diameter provided with a slightly fitting
lid 10.5.1.3 Electrical oven equipped
with thermostat
10.5.1.4 Desiccator with an efficient
desiccant
10.5.2 Procedure
Weigh accurately about 5 g of the sample in a dried
and weighted aluminum container provided with a
slightly fitting lid. Heat the uncovered dish with
its lid in an electrical oven at 1.00 2°C for 2
hours. Remove the container from the oven and immediately
cover it. Cool the container in the desiccator and
weight. Repeat this process of heating for 1 hour,
cooling and weighing till the difference in weight
between two successive weighings in less than one
milligram. |
