I am teaching Introduction to Microbiology to non-Biology majors. In my career as a scientist, I have always worked with one culture tube at a time and so, taught that to my students.

My professor, on the other hand, wants us to teach the students to open two tubes at the same time, so that you can transfer tube to tube immediately.

I can see that this reduces the risk of aerosol from the loop (broth culture) while you are replacing the culture tube onto the rack. However, I am more concerned about students dropping (or mixing up) the tubes, caps or loop, while in the somewhat awkward position. Since we are not flaming the tubes anymore, I am not sure it is worth getting them through this learning curve.

In addition, for inoculation of slant or stabbing and streaking the deep slant (eg. TSI), where a considerable amount of visual is required on the sterile media, I am not sure that handling the open stock tube at the same time is a good idea.

I know holding two tubes at the same time can become second nature very fast, but I thought I would just find out what most microbiologist prefer to use and teach.