Expired Milk Under the Microscope

  • Published on:  4/7/2019
  • Microscopic footage of milk before it expires, after it expires on its "best-by-date" and after being incubated to speed up microbial growth. I also tested for bacteria at each stage with a petri dish to quantify bacterial colonies. I believe the most common bacteria after the milk was incubated to be lactobacillus because of the following criteria: gram positive rods, growth on complex medium (milk, Tryptic soy agar), non-pathogenic since the milk was pasteurized, Indole negative, Citrate negative. This is the best guess I can make with the medium and tests available to me in my lab. Visit the links below for more information on:Homogenization: https://en.wikipedia.org/wiki/Homogen...)Pasteurization: https://en.wikipedia.org/wiki/Pasteur...Expiration dates and how to store milk: https://www.eatbydate.com/dairy/milk/...Curd: https://en.wikipedia.org/wiki/CurdWhey: https://en.wikipedia.org/wiki/WheyI used a Nikon D3300 DSLR camera and a Leica ATC 2000 Microscope for this video.The Microscope magnification of each shot is shown in the bottom right hand corner. Music is written and produced by Sci-inspi.