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Methylene Blue Reductase Test ( Analysis of Milk)

Methylene Blue is an organic compound , in dark green or lustrous crystalline powder, used in the treatment of methemoglobinema, as a strain in pathology and bacteriology, and as a diagnostic aid in the detect ion of premature rupture of fetal membranes.

Objective: To check microbial load in the milk sample. To check the quality of milk sample.

Requirements:1. Milk sample 2. Methylene Blue dye3. Test tubes4. Test tubes holder5. Test tubes stand6. Water bath or incubator7. Dropper or Pipettes and its tips8. Swab cotton9. Aluminum foil

Procedure : A. Take test tubes and pour 10 ml of milk sample in each test tubes.B. Then labeled the test tubes.C. Then add drops of Methylene Blue Dye in each test tubes.D. Next incubate the test tubes at 37 C in water bath for 15 minutes.E. Result: Absorb the color of the test tubes with respect to times.F. If the color is changed its means that the milk sample having contamination

( Load of Microbes), and the quality of milk is not good, while if there is no color changed in the test tubes, its means the quality of the concern milk sample is good.

Amjad Khan Afridi 8th August , 2016

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Interpretation:

If dye color is disappear in 30 minuets , its means that the milk has very bad ( Poor) quality.

If dye color is disappear in 1 hour , its means that the milk has bad quality. If dye color is disappear in 6 hours , its means that the milk has fair quality. If dye color is disappear in 8 hours, its means that the milk has good quality. If dye color is disappear in 24 hours, its means that the milk having

excellent quality.

Demonstrated By Madam Sadira 8th August , 2016

Prepared by Amjad Khan afridi, 7th semester

Amjad Khan Afridi 8th August , 2016