Microscopy of cheese mould 10/6/2017

I popped into the kitchen one hour ago to make my lunch and found the following……

Some people would go “urrrhhhh……” – but for me I thought what a great opportunity to look at this under the microscope!


Observations of non-affected part of cheese as comparison with affected part

I was shocked when I looked at a part of the cheese that appeared not to be affected by mould – in fact the section of cheese used for this came from INSIDE the cheese! I knew that cheese was effectively rotten milk but when I looked I saw active diplococci bacteria and another ciliated round organism which I could not identify. I did not realise the cheese was just so alive! These bacteria became visible at 32x objective (with standard 10x ocular this would equal 320x – however I was using the Bresser camera instead of the an ocular).

All photos and videos below taken with Bresser MikrOkular HD camera.


Video of microscopy of “normal” cheese from the sample showing bacteria that look like small dumbbells moving around (below) – I think these are lactobacilli as on this link – http://blog.microscopeworld.com/2014/11/lactobacillus-under-microscope.html

Video of apparently normal cheddar cheese sample 32x Zeiss long distance objective – initially video is in bright field then changes after a while to phase contrast using Phase 1 annulus that this objective was designed to be used with (below). There is an air bubble in top right of video and the background is out of focus material in different image plane. Bacteria are visible moving in the video. It is worth blowing this up to full screen to view the bacteria.


Cheese-non-mouldy-part-bacteria-cannot-be-seen-10x-bright-field-image-100617.bmp (below):

Cheese-non-mouldy-part-bacteria-present-but-not-obvious-20x-Zeiss-phase-objective-LWD-bright-field-image-100617.bmp (below):

Cheese-non-mouldy-part-showing-active-bacteria-32x-Zeiss-phase-objective-LWD-bright-field-image-100617.bmp (below):

Cheese-non-mouldy-part-showing-active-bacteria-40x-objective-bright-field-100617.bmp (below):


Cheese-non-mouldy-part-showing-active-bacteria-are-diplococci-32x-Zeiss-phase-objective-LWD-bright-field-image-100617II.bmp (below):

Two images below are phase contrast images using 32x Zeiss LD objective and phase 1 annulus that it was designed to be used with. Note the rainbow-coloured segment of a circle in upper right each image is an air bubble:

Microscopy of fungal sample from cheese

I scraped off a sample from the edge of the same cheese as above which as infected with green fungi – photos below show that this did not show bacteria. Instead, there were masses of fungal spores – and virtually nothing else. I think this might mean that the fungi were penicillin types – producing the antibiotic penicillin and killing off any bacteria in its vicinity. Even 1cm into the cheese, the “normal” cheese still had some green in it and those areas had no bacteria but the areas without green tinge were where the bacteria were found. Shows how far the fungi stretches into the cheese – yipes! However if it is penicillin then it is probably the safest bit of the cheese to eat…….

Sample-scaped-from-green-fungi-on-cheese-brightfield-10x-showing-large-numbers-spores-100617.bmp (below):

Sample-scaped-from-green-fungi-on-cheese-brightfield-20x-showing-large-clumps-spores-100617.bmp (below):

Sample-scaped-from-green-fungi-on-cheese-brightfield-32x-showing-detail-spores-100617.bmp (below):

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