Cold storage - Onions room

[Kevin Yeo]

Dear all,

To size a chiller room (0 to -3 deg C) for onion and garlic room. Any special coatings required on unit coolers cooling coil?

Products are exposed and stacked using pallets.

Any other things to take note, such as ventilation etc?

Thanks a lot...

[botrous]

Yes the odor of the onion and garlic , you sure need a super shower each time you enter the room :)

[Temprite]

I couldnt say for sure but, I think you would definetly have to treat the evaporator.

Underbench fridges are notorious for losing the evap coils due to the corrosive nature of the foods that are stored in them.

Some manufactures supply treated evaporators or you can buy cans of it yourself to treat the coils.

Chemi mentioned spraying I think epoxy resin into evaporator coils in a coolroom storing cheese I think.

He may well be able to give you some good advice.

[US Iceman]

Kevin,

Here is some additional information you may find useful,

http://vric.ucdavis.edu/selectnewtopic.undergnd.htm

Look under the section titled "Recommended Storage Conditions"

http://www.extension.umn.edu/distribution/cropsystems/DC7060.html#1005-26

Here is a link to a coating supplier. I have used this before on applications where corrosion was anticipated. Since this is a coating, it can be damaged. Once this happens, it is only a matter of time until the corrosion gets under the coating.

http://www.heresite.com/index.htm

I don't have any first hand experience with this commodity, but hope the information above helps you.

You might also try the ASHRAE handbooks. Otherwise, you need to find someone who has done this before.

I would recommend the pallets be stacked on racks to promote even air circulation over the products. Also, the pallets should not be stacked too close to the walls.

This allows the air to circulate around the pallets, and helps to maintain a uniform air temperature around the pallets.

The unit coolers should be located away from the walls at least equal to the unit cooler height. More if possible.

I would also suggest the air flow from the unit coolers to be directed towards the storage doors. This helps to control infiltration of moisture and helps to reduce condensation on the bottom of the unit coolers, when warm air enters.

I would not recommend the unit coolers be placed above the storage doors. This is when condensation occurs on the unit cooler drain pans.

Regards,

[frank]

Any special coatings required on unit coolers cooling coil?


Don't forget to allow for the decrease in effiecency of the coil due to the coating when sizing the evaporator

[Steve Wright]

US Iceman is right on target.

We have done these rooms with the heresite coating, it gives good corrosion protection, minimum heat transfer reduction (less than 1%), and no bridging.

You might also consider using copper fins.

Steve

[chemi-cool]

Hi Steve/
Its the first time I hear about keeping onion and garlic in cold storage.
We keep them uot' in the sun so they will get dry.

Chemi:)

[Peter_1]

Goedhart makes stainless steel evaporators +/- 20% to 30 % more expensive than the standard types.

I think you have to store them the same way we store here apples and pears in a CA.

[Steve Wright]

Yea Chemi

In the US we eat our onions wet and our garlic dry.

Haven't you heard that the Vidalia onion is the sweetest in the world, we have people that make sandwiches out of them.

I like to hear from you and guys like Peter_1 because I'm learning about how you guys do things in the other part of the world.

Steve

[botrous]

Haven't you heard that the Vidalia onion is the sweetest in the world, we have people that make sandwiches out of them.


I can't support onions , the only way that i eat it , is coocked , and with other things , maybe in salad (occationally) . . . but eating an onion sandwich ....................................

[chillin out]

I can't support onions , the only way that i eat it , is coocked , and with other things , maybe in salad (occationally) . . . but eating an onion sandwich ....................................
Onions are my farourate food have them with anything or just on there own.

mmmmm nice.:) :)

[botrous]

Annnnnnd girls will like you Chillin , after some fresh onions , you will be the most wanted by women :)

[US Iceman]

Hi Botrous,

I went to school with a girl who ate onion and peanut butter sandwiches. She was a very nice looking girl who had no shortage of guys chasing her.

Perhaps if it was the guys eating the sandwich and chasing girls the situation might be different??? :D

Sometimes it does not matter, heh? :p

US Iceman

[botrous]

Perhaps if it was the guys eating the sandwich and chasing girls the situation might be different???

I bet this is true

[chillin out]

Annnnnnd girls will like you Chillin , after some fresh onions , you will be the most wanted by women
Hope not, wife might not like that.:)

I went to school with a girl who ate onion and peanut butter sandwiches. She was a very nice looking girl who had no shortage of guys chasing her.

Perhaps if it was the guys eating the sandwich and chasing girls the situation might be different???

Sometimes it does not matter, heh?

US Iceman
Reply With Quote
You saying I want guys chasing me?;)

[botrous]

Hope not, wife might not like that

She sure will not :)

[US Iceman]

Hi Chillin out,


You saying I want guys chasing me?

That is not exactly what I had in mind!!! :o

US Iceman

[Vandy422]

US Iceman is right on target.

We have done these rooms with the heresite coating, it gives good corrosion protection, minimum heat transfer reduction (less than 1%), and no bridging.

You might also consider using copper fins.

Steve

I have specked Heresite before but with poor results as it is brittle and pops off of the fins. Carrier had recommended an Epoxy Ecoat called ElectroFin which we now recommend on harsh or corrosive applications. Have not had any complaints in 3 years.

[Kevin Yeo]

Guys,

Thanks for the useful information.

rgds,
Kevin

[john doersom]

We stored WALA-WALA and Vidalia in our cold storages during the years 1992-1996.

Ideal storage is 65% Rel. Humidiy at 34 deg.F.

We were able to convert our apple storage buildings to make the above parameters for the onions.

Onions came to us wet. For the first 3 days, we used the evaporator fans to dry them out. When the rooms got to be about 65% rel. hum, we then started lowering the temp.

To keep the RH in check, it was necessary to create a load (heat gain) by turning on the defrost heaters for an hour at a time on one system while refrigerating the room with the other system.

AIR MOVEMENT over the boxes of onions is crucial.

Sweating of the onions will occur in July after taking them out of the cold storage. However, the refrigerated containers used for shipment kept the temp at 55 deg. F, and the RH at 65%.

Ideal marketing is put the onons in an air conditioned food market., not in a walk-in cooler.

[Chandra]

Hi,
I am planning to start a Cold Storage units for Onions and Tomattos. I live in India. Could you please someone kindly guide me - what are the procedure and where can i find information about how to store onions/tomato/potato, what type of cold-storage units require to store onions /tomattos/potato.

Thanks
Chandra

[Josip]

Hi, Chandra :)

welcome to RE forums...


Hi,
I am planning to start a Cold Storage units for Onions and Tomattos. I live in India. Could you please someone kindly guide me - what are the procedure and where can i find information about how to store onions/tomato/potato, what type of cold-storage units require to store onions /tomattos/potato.

Thanks
Chandra

Please make search on RE forums....there are a lot of posts with links to appropriate documentation regarding...harvesting...post harvesting...and storage of onion/potato/tomato

for beginning, here is one link....

http://www.fao.org/inpho/content/compend/text/ch26.htm#TopOfPage

hope that is of some help;)

....it is not a simple task at all:D

Best regards, Josip :)

[rajgulati]

To get the temperature of onions you must run your compressor at lower suction i.e. 12- 15 C TD. As TD is higher RH decreases. In onion cold store you require hot gas or electric heaters defrosting and heater bank at the front of cold coils i.e at the discharge of air.


Thx.
regards

[jwasir]

Hi Chandra,

For Onions and garlic storages, RH plays a vital role.

You have to use reheat system.



Regards,

[Samarjit Sen]

Hello Chandra,

What exactly would you like to know about the storage facilitiy. Every product has its individual requirement. To be able to help you, I would like to know the specific product, quantities, from where is it coming ie. from the field after harvesting or are they from the market etc.

[Samarjit Sen]

Hi jwasir,

Onion and garlic requires a RH ranging from 70 to 85%. I do not feel that reheat is required. The evaporators should be capable of maintaining this RH. It is because of these reasons, that I always suggest that individual produces should have separate rooms as each product requires a different temperature and humidity

[jwasir]

Dear Mr. Sen,

In one case we were having problems as garlic was getting wet but temp. was going down.

So we have to add some resisitive heaters in the room.

You are absolutely correct that individual produces should have separate rooms.

Sometimes there is misconception between absolute humidity and relative humidity.

[Michael Kennedy]

Hi,
I am planning to start a Cold Storage units for Onions and Tomattos. I live in India. Could you please someone kindly guide me - what are the procedure and where can i find information about how to store onions/tomato/potato, what type of cold-storage units require to store onions /tomattos/potato.

Thanks
Chandra

Hi
This is my first post to Re

[Magoo]

respiration rates are high and humidity control is critical, would recommend stainless steel pipe and fin evaps and CO2 monitoring with lots of fresh air make up, as they can go to mush over night if RH and CO2 get out of spec..
cheers Magoo

[nike123]

Hi
This is my first post to Re

I love tradesman's!
After journalists, then politicians and lawyers, they are most agile kind of peoples. I wish I could have at least 10% of their agility.;)

[cakabo28]

be careful about moisture otherwise onions can leaf out and turn green :)

[The MG Pony]

Well michael keep going at that rate will end up being your last post!