UV lights in food production

[pastrygirl]

Recently I watched a visit to an Entemann's bakery where they ran all the doughnuts under a UV light to kill mold spores before packaging.  A few days later I was at Staples, where they had 'room sanitizing' UV lights on clearance and I'm thinking it couldn't hurt to get one and shine it on my bonbons before I cap them.  Also to sanitize the kitchen in general, especially the walk-in fridge. 

 

Does anyone have experience with UV lights in a food production setting?  Will the cheap one from the office supply store help me at all? 

 

thanks!

[Jim D.]

Very intriguing idea.  I found this on the Environmental Protection Agency website:

 

If properly designed, ultraviolet germicidal irradiation (UVGI) cleaners that use ultraviolet radiation from UV lamps may destroy indoor biological pollutants such as viruses, bacteria, and some molds that are growing on the moist interiors of HVAC surfaces (e.g., cooling coils, drain pans, or ductwork).  But typical UVGI cleaners used in homes have limited effectiveness in killing bacteria and molds. Effective destruction of some viruses and most mold and bacterial spores usually requires much higher UV exposure than is provided in a typical home unit.

 

Also found this info:

 

As effective as UVGI may be, it's not a practical mold solution all the time for several reasons. The first is that the light must come in direct contact with the mold spores in order to kill them. This makes it possible to kill mold spores in the air and on solid surfaces. The light may not penetrate deeply enough, however, to kill mold spores safely tucked away in porous surfaces, like drywall.

 

On the other hand, one assumes that a company as large as Entenmann's must have support for what they are doing (inspectors, e.g.).

[dcarch]

I have been using UV light to sanitize everything during the entire pandemic. 

I also us UV light to generate ozone to sanitize fruits and vegetables which I don't want them to be watery or soapy.

 

Please read up on UV light before using. There are many kinds of UV light and some dangers if used improperly.

 

dcarch

 

[pastrygirl]

 

@Jim D. good points.  The doughnuts pass through on a conveyor belt, only getting a brief exposure so it must be super strong? 

 

@dcarch can you tell me what you use? 

[rotuts]

perhaps the idea 

 

is to kill some spores ,on the surface ,  to extend shelf life

 

knowing full well its not going to kill them all.

 

 

[Jim D.]

@pastrygirl, too bad the Entenmann's photo is not taken so as to show the brand name of the machine.  That would reveal a lot.

 

I also found this useful information on the type of UV light that would be required:

 

The type of ultraviolet light that's able to effectively get rid of mold is UV-C, which is a very short wavelength of UV light. Because of how beneficial UV light can be at the right amounts, this light is commonly used for disinfection purposes, which can include treating ballast water with UV disinfection.

[gfweb]

I'd want to see data on spores. Those are designed to survive and are particularly tough.

 

And, yes, UV-C is the right one.

[gfweb]

A quick google yields a bunch of manufacturers claiming 99% sporocidal activity.  Still looking for a research paper or 2.

 

99% sounds great but all it takes is one survivor.  Typically there are hundreds of spores that contaminate, so there would certainly be survivors of UVC. 

 

I'm tempted to say that Entenmann's must know what they are doing, and I'm sure that they do, but I'd bet the UVC on the doughnuts is just part of a comprehensive facility-wide plan to minimize spoilage.

[dcarch]

51 minutes ago, pastrygirl said:

 

@dcarch can you tell me what you use? 

 

I can only tell you that UV light is very powerful at 50w that I am using. When I put a bag of bananas under the light for 15 minutes, the bananas will get a suntan even they are in a thick plastic bag.

 

I cannot tell you exactly about my setup because I don't want to endanger anyone if somehow the details are not properly considered.

 

dcarch

Edited February 23, 2022 by dcarch (log)

[rotuts]

I don't think UV light is necessarily used to

 

sterilize , even if that's possible .

 

many many years ago i worked

 

in a Univ. Infectious disease Lab.

 

back then , the dept. made all or most of the 

 

petri-dish medium to grow what was needed in the

 

Univ. Hospitals ID identification lab 

 

what's were your ' cultures ' go to sort out.

 

in the room where all this got done , and much more 

 

when the door was shut at night , banks of UV lights came

 

on.  not a few , one or two , but like arrays of fluorescent like  lights on

 

the ceiling.   when the door was opened

 

they turn off .  im sure thy were not looking 

 

to have a sterile ' kitchen'  in the morning 

 

but one w less chance of contamination when making 

 

media  ( the gell the bottom of the peri-dishes )

 

if something needed sterilizing 

 

( liquid media in flasks )

 

it got autoclaved.   im sure the liquid

 

poured into the already sterile plastic perti dishes 

 

had to have been autoclaved , then cooled

 

before the ' pour '

 

and indeed , the room was a big kitchen .

Edited February 23, 2022 by rotuts (log)

[pastrygirl]

8 minutes ago, dcarch said:

I cannot tell you exactly about my setup because I don't want to endanger anyone if somehow the details are not properly considered.

 

Thanks, I understand.  I'm reading up on the risks.

 

After 15 min, are the bananas warm?  Would your light melt chocolate or butter?  I hadn't thought about how hot it might be.

 

I worry about whatever is floating around in the air while the bonbons sit and crystallize, but sounds like treating the kitchen as a whole

when un-occupied would be safer than treating the items directly while I am working in the room. 

 

 

 

[rotuts]

any bakery that uses flour

 

has to be a Yeast-Buds paradise 

 

some are at work helping 

 

your bread to rise. 

[gfweb]

Might be unanticipated Osha issues w UV

[rotuts]

the media room

 

had the odor of agar , w hints of

 

sheep's blood .

 

I do recall the UV lights were very difficult to turn on

 

manually .

Edited February 23, 2022 by rotuts (log)

[dcarch]

15 minutes ago, pastrygirl said:

After 15 min, are the bananas warm?  Would your light melt chocolate or butter?  I hadn't thought about how hot it might be.

 

The UV killing of microbes is not with heat. The high energy UV light waves destroy. break apart biological molecules, making them not functional.

 

Chemical sanitizers claim to be 99% effective. May be. But it will require 100% contact. When you spray, the droplets will not give you 100% contact with germs.

 

 

dcarch

[dcarch]

17 minutes ago, rotuts said:

I do recall the UV lights were very difficult to turn on

 

manually .

 

For ballast powered Mercury bulb UV light yes. And if you turn the light off, you have wait 5 to 10 minutes cool off time before they can be turned on again. But there are ones that work like a regular florescent tube, on and off just flip a switch.

 

UV kills germs in air with 100% coverage.

 

I don't trust LED UV lights.

 

dcarch

 

Edited February 23, 2022 by dcarch (log)

[rotuts]

excellent points 

 

@dcarch 

 

by difficult to turn on

 

re those lab kitchen lights 

 

I meant by a DoDo in the middle of the day .

 

if one would need and be able to afford

 

a UV system where the kitchen // prep area 

 

in a home , got tossed at night 

 

w Pet , and other sorts of safety 

 

it would be interesting to see 

 

what was accomplished .

 

I mean that neutrally 

[dcarch]

1 minute ago, rotuts said:

if one would need and be able to afford

UV germicidal light may be affordable. My setup is about $50, not including extension cord and a tripod to move the light around different parts of the house.

 

dcarch 

[dcarch]

Totally off-topic.

 

If you have no life, and you are a maker and fixer of things like me, you can get glue that sets instantly with UV light. The kind of glue a dentist uses.

 

dcarch

[cdh]

Are you using one of those water purifier setups that  has a long UV bulb inside a quartz tube inside a sealed and non-seethrough housing?   UV generally is pretty scary... it is not visible, but if you look at it without eye protection you can wreck your retinas really quick... 

Edited February 23, 2022 by cdh (log)

[Kerry Beal]

Hubby built me three UV sterilizers at the onset of Covid - one went to the isolation center to sterilize N95 masks, face shield etc. The other to one of the clinics. 

 

 

 

Perhaps it's time to bring them home for chocolate - however I haven't had a moldy ganache for a long time (it would be really bad form since I'm the shelf life tutor for Ecole Chocolat).

 

 

[gfweb]

1 hour ago, rotuts said:

the media room

 

had the odor of agar , w hints of

 

sheep's blood .

 

I do recall the UV lights were very difficult to turn on

 

manually .

I spent a long time around hot agar. Every once in a while I catch a whiff of boiling yeast extract and it takes me back to my youth. 

 

 

[Kerry Beal]

3 minutes ago, gfweb said:

I spent a long time around hot agar. Every once in a while I catch a whiff of boiling yeast extract and it takes me back to my youth. 

 

 

For me it's the grape jelly smell of pseudomonas 

[gfweb]

4 minutes ago, Kerry Beal said:

For me it's the grape jelly smell of pseudomonas 

That too. 🙂

[KennethT]

57 minutes ago, Kerry Beal said:

Hubby built me three UV sterilizers at the onset of Covid - one went to the isolation center to sterilize N95 masks, face shield etc. The other to one of the clinics. 

 

 

 

Perhaps it's time to bring them home for chocolate - however I haven't had a moldy ganache for a long time (it would be really bad form since I'm the shelf life tutor for Ecole Chocolat).

 

 

I used to use a UV device for psoriasis and it had 4 sets of bulbs that looked just like yours!