5 replies to this topic

[astro]

Hi

 

Before I start I know my thoughts on this but I was hoping to get some other thoughts and advice.

 

We are a high care prep facility for chopped fruit. Our current process for example is grapes are devined by hand, wash in a grape bath with chemicals then enter the high care side into trays ready to put into pots.

 

Currently operations have just gone off as we having a big project for automation, so as said they have gone out as they know best purchased a desteming machine to mechanically remove the grapes form the stem they they will go through a UV tunnel. So what are people thoughts and do you see a problem with this as I may need some help.

 

If I can give more info let me know

 

Cheers 

[jfrey123]

What's the end use?  For example, a lot of the grapes you buy in store still bunched comes with notes for the users to wash before consuming.  But you're saying you're a cut fruit facility, so I'm guessing you're packing grapes in tray offerings.  I would be uncomfortable with deleting the wash step entirely.  I don't know enough about UV tunnels to have a helpful insight, but I'd speculate you'll end up with a bunch of dirty grapes that have been "sanitized" via UV.

 

Probably sounds great to one of your execs, "Sanitize without water!"  But the grapes are still dirty to begin with.

[Tony-C]

Hi astro,

 

Removing the washing stage and replacing it with UV would concern me as well.

 

UV works well on flat surfaces that are close to the light so for example flat packaging such as foil lids.

 

The problem with UV is the proximity and shadowing, I have experienced these problems on a new production line and in the end the project switched to a rinse.

 

My question would be how is the UV tunnel set up to ensure that all parts of the fruit receive UV coverage at the right intensity to kill the microbes of concern?

 

Kind regards,

 

Tony

Edited by Tony-C, 13 December 2025 - 06:44 AM.

[GMO]

I agree with previous comments on UV having limitations.

I have to admit though I have some reservations too about destemming first before decontamination steps. Admittedly I've not worked in grapes but I'd imagine the number of damaged fruits after destemming could put pathogens in contact with a surface it's difficult to clean off (i.e. where the stem joined) and some grapes will be actually oozing juice there providing a food source. Gut feel and gut feel alone, I'd like to use a water bath using appropriate disinfectant chemicals then destem after it.

 

BUT it has to be said, those wash processes are MUCH less effective than you think. 1-2 log reduction is often the best you'll get. And if you can overcome shadowing, UV is pretty effective against viruses which are probably a pretty high risk on your product. If you could incorporate a washing process AND UV that would be better. But I'd max out whatever you do on the validation.

[Tony-C]

I have to admit though I have some reservations too about destemming first before decontamination steps. 

 

Interesting you say that GMO, I had someone who worked in one of my NPD teams that did some research on where to do the washing step in the process of preparing produce.

 

Are you saying that de-stemming after washing is better based on any scientific evidence? if so please post a link.

 

Kind regards,

 

Tony

[GMO]

Interesting you say that GMO, I had someone who worked in one of my NPD teams that did some research on where to do the washing step in the process of preparing produce.

 

Are you saying that de-stemming after washing is better based on any scientific evidence? if so please post a link.

 

Kind regards,

 

Tony

 

No it's purely gut feel, and, I suppose thinking of the toffee apple Listeria outbreak where pathogens either from the surface or from the stick then grew like billy-o once it came in contact with the juice from breaking the surface. I am fond of grapes personally and when removing the stem, it does feel that the skin breaks on a relatively frequent basis. That skin breaking as well will put juice into whatever equipment you're using to decontaminate either using up the disinfectant or creating great growth conditions (or both).

 

But yep, just based on gut feel. If you have any papers from your ex-colleague or ones they know of, I'd be interested and I'm sure the OP would be too.