If there is a basis to allege that a food has initiated the food poisoning or has endured microbial spoilage, the original product or a low serial dilution of it must be utilized in order to prepare a microscope slide for direct microscopic investigation under a microscope such as the digital compound microscope. The Gram stain response and cellular morphology of the bacteria on the microscope slide can possibly imply the necessity for other kinds of examination. Microscopy using a microscope like the digital compound microscope should be performed although the food may have actually endured heat treatment and the microorganisms included may no longer be viable. Huge numbers of Gram-positive cocci on the microscope slide as observed through microscopy under a microscope such as digital compound microscope may suggest that there is some existence of staphylococcal enterotoxin, which is not killed by the heat treatments that can obliterate enterotoxigenic Staphylococcus aureus strains. Big numbers of the sporeforming, Gram-positive rods as seen by means of microscopy using a microscope such as digital compound microscope in a frozen food specimen may denote the existence of Clostridium perfringens, which is an organism that is receptive to low temperatures. Other Gram-positive, sporeforming rods like the Clostridium botulinum or Bacillus cereus may also be existent in the food. When microscopy under a microscope such as digital compound microscope of alleged food reveals the existence of numerous Gram-negative rods, consider the signs and incubation periods reported for the disease under investigation and choose the particular examination procedure for segregating one or more of the genera Campylobacter, Salmonella, Escherichia, Shigella, Yersinia or Vibrio.
The foods can be examined directly through microscopy using a microscope. Microscope glass slides, methanol, xylene, immersion oil, the microscope itself, wire loop and the Gram stain reagents are the things needed. A film of mixed food specimen are to be prepared and to be examined not less than ten fields of every film noticing the prevalent kinds or organisms specifically clostridial forms, Gram-positive cocci and Gram-negative bacilli.
In case of microscopic examination of eggs under a microscope, the materials needed are the microscope slides, bacteriological pipet or metal syringe, north aniline methylene blue stain, lithium hydroxide, a microscope, physiological saline solution, Butterfield’s phosphate-buffered dilution water, xylene and ethanol. Prepare a film to be dried up naturally, stain the microscope slide, washed it and completely air-drying it prior to its examination. Then count the microorganisms viewed.
In case of microscopic examination of dried egg products, completely combine sample, then prepare dilution. Then mix the other materials needed, and allow the bubbles to escape. Put the diluted dried egg material on clean microscope slide and spread it evenly then proceed to the examination of eggs using the microscope. Multiply the number of microorganism found for every field by twice the microscopic factor. Though this is not the very detailed way of determining the microorganisms in the food or eggs since specific quantity of reagents or solutions are still necessary for this to be effective.Continue research on this page