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Accurate humidity control is the key to maintaining quality fresh produce in cold storage. All cold storage systems remove water vapor from the air in the store room. The dry air increases transpiration and water loss from the stored product, resulting in lost weight and lost value. Potatoes stored without added humidity can lose 10-12% of their weight over six months. Optiguide's "dry fog" can reduce weight loss to 2% without wetness. Only the Optiguide system can provide controlled high humidity at 95-98% RH and preserve freshest quality. Evaporative coolers and spray disc systems can't reach this level with uniform coverage and no water on the crop.
Not only potatoes! Sweet potatoes, carrots, onions and bulbs all remain fresh and dry with Optiguide's controlled "dry fog".
The Tabor FogRight uses micro droplets of water to produce a true dry fog. The OptiSense controller constantly senses the RH, up to 98% without becoming saturated, and turns the fogger on and off. Adding water vapor to the air reduces the transpiration rate of the tubers. The tubers remain dry on the surface, and keep their moisture within.
The fogger system can be installed in rooms with a plenum, or in open circulation rooms, for storage in bins, bags, or bulk. Its modular design allows installation in the largest or smallest storerooms, and more rooms can be added-on with reduced marginal cost.
Prevents weight loss: High relative humidity means the surrounding air cannot hold more water vapor, so the weight of the water stays in the potato, not evaporated into the air.
Maintains price: Water loss and less firmness mean lower quality potatoes - and lower prices for the crop. Quality prices after storage with Optiguide's Controlled Humidity Solution pay back installation costs in the first season.
Extends storage time: Since potatoes maintain higher quality for a longer time, there is little danger of "deteriorating rooms" Stores can hold their crop for the best market periods.
Extends shelf life: After storage, a full, firm potato has a longer shelf life from grocer to consumer.
Maintains Firmness: As water loss breaks down cell turgor, potatoes lose firmness. High humidity keeps potatoes firm for the sharpest, most even cuts, so that chips and fries absorb less oil in frying.
Maintains starch content: In potatoes stored with poor humidity control, starch converts to sugar. High humidity prevents starch breakdown for whiter color in crisps and fries and chips.
Allows higher storage pile: With uniform high humidity and no condensation, firm potatoes can be stored in higher bulk piles. Increasing pile height by 10% without loss of quality saves storage costs.
Used for spray treatments: The Tabor FogRight Atomizer has a large 1.5 mm orifice. It can be used for anti-sprouting and anti-bacterial spray, without clogging.
Onions stored at 80% RH keep fresh without mold.
Carrots can be stored at 0 C. Only the Tabor FogRight's "dry fog" evaporates directly into the air without icing - even at below 0 C.
For major potato users, today's losses can be tomorrow's savings. At a contract price of $100 a ton, 100,000 tons of potatoes in storage can lose $1 million in six months. Optiguide's Controlled High Humidity can save $800,000.
Even smaller users save: A 6,000 ton potato storeroom can hold product worth over $1 million. Weight loss of 10% means $100,000 going up in the air each season. The Optiguide system can reduce weight loss by 75%, at a cost of $15,000. This means savings $75,000 per season from reducing weight loss alone. The Optiguide system pays for itself 5 times over in one season!
But that's only the savings from weight loss. Higher quality and longer storage ability make the Tabor FogRight Atomizer and OptiSense Humidistat a profit-making team.
Regev Cold Storage is one of the largest cold storage facilities for potatoes in Israel. Since 1998 they have equipped 13 cold storage rooms with the FogRight Atomizer and the OptiSense Humidistat. In their third season with the system, they built a new facility with three rooms - and installed the complete Optiguide system.
Yehuda Hamawi, Managing Director, explains: "In each of our 1500-ton rooms, we have four atomizer nozzles. They supply "dry fog" which maintains 95% RH, and we don't get any standing water. Each season we give the atomizers an annual maintenance check just before the season. It takes 4 or 5 hours for the job. In May of 1999 we tried the OptiSense Humidistat - which gives the controls to the atomizers - in one cold storage room. After that first season, we have now put the Humidistat in all 13 of our rooms and connected them all up to the central computer. This way we can keep a full history of the relative humidity in each room - and we can also change the humidity settings from the central computer. We are very satisfied with the operation."
Galil Cold Storage in northern Israel uses the Optiguide system in 14 rooms and intends to equip more next season. "We have used the Tabor FogRight Atomizers for 4 years, mostly for storing carrots in rooms from 300 to 400 tons. The results have been very good. Now the growers insist that we store their produce using "dry fog" humidifiers," says Brian Eisen, Operations Manager.
 
Low Sugar Chips A major international potato chip producer had two rooms of identical potatoes, all harvested from the same grower, on the same day, stored by their supplier in southern Israel. They were already using a humidity system with a timer that gave them 85% RH. They installed the OptiSense Humidistat and FogRight Atomizer in one room, and raised the RH to 95%. After 3 months storage, they processed the potatoes for chips, and called us to look at the results:
 
The American Journal of Potato Research reports on tests of the Optiguide Tabor FogRight system, conducted in 1999 by Israel's Volcani Agricultural Research Center. The summary:
"A new fogger -the Tabor Atomizer system - features unique atomizers based on compressed air and water. The droplets have a very small mass (less than 10 m.) and behave like a dry cloud, producing 96-98 % relative humidity (RH) without depositing free water on the tubers. After 6 months of storage at 10 C, with 96-98% RH applied with the Tabor Atomizer System (room A), 92-94% RH applied with a spin-disk humidifier (room B) and 82-86% RH with no added humidity (room C), the weight losses for stored potatoes were 2%, 7% and 12%, respectively. The firmness of the tubers expressed as Newtons (N) required to penetrate the tubers before storage and after 6 months in room A, B, or C was 76, 74, 68, or 63 N, respectively."
Data from "Using the Tabor Atomizing System to Maintain Weight and Firmness in Stored Potato Tubers" , Uzi Afek, Janeta Orenstein, and Ephraim Nuriel; American Journal of Potato Research (2000) 77:203-205.
For the full research paper and more information, please contact us.
 
Storage rooms need anti-bacterial treatments to clean the storeroom before the season. Potatoes in long-term storage must be treated to prevent sprouting. Uniform spraying in a full storeroom is a difficult and sometime dangerous task. The FogRight Atomizer does double duty for all spray applications: fungicides, anti-sprouting agents, anti-bacterials. Its automatic operation allows uniform dosage throughout the stored crop and avoids the hazard to workers' health, and to the environment.
The large 1.5 mm orifice in the nozzle won't clog like pin-hole foggers do, so very little annual maintenance is required. The spray is atomized into the air to reach all surfaces uniformly throughout the bulk pile or in all the bins. By controlling temperature and humidity, the spray can remain in the air or can be allowed to condense on the produce. Automatic controls enable spraying with no exposure of workers.
Makhteshim - Agan, a world leader in agricultural chemicals, is using the Tabor FogRight Atomizer as the exclusive delivery system for its new hydrogen peroxide anti-sprouting formula, now being tested.
Optiguide's Atomizer has been tested in spray applications of HPP (Hydrogen Peroxide Plus) at the Gilat Experimental Station. From their report:
"Potatoes (Solanum tuberosum L.) samples, cv. Desiree, were treated for sprout control and stored at 10 1 C for 6 months. Those treated four times with HPP (hydrogen peroxide plus), applied with the "Tabor Atomizing System" had a 0% rate of sprouting, while the non-treated control had 84%.
...Results of the present study show that HPP applied with the Tabor Atomizing System is effective as a sprout inhibitor. The technology of this fogger is based on compressed air and water; it produces very small droplets that have almost no mass, carrying the HPP as a weightless gas that covers the potatoes in the storage rooms.
...Application of HPP by fogging with the Tabor Atomizer is a method that is friendly to the environment, easy to implement, and inexpensive."
-from "Using HPP (Hydrogen Peroxide Plus) to Inhibit Potato Sprouting During Storage", U. Afek, et al; American Journal of Potato Research (2000) 77:63-65.
For the full research report and more information on spray treatments using the Tabor FogRight Atomizer, please contact us.
 
Controlled Atmosphere storage at -2 to + 4 C slows down the transpiration process and prevents decay, but very low-temperature cold storage dries the fruit, as water is lost into the dry cold air. Drier fruit is lower quality fruit, and the lost water means lost weight and lost profit. Washington State apple growers have reported weight loss of 5% over the 8 month storage period.
Long term storage in sealed CA rooms demands the most reliable humidity addition system, and complete control from outside the storeroom. The "dry fog" Tabor FogRight Atomizer and the OptiSense Humidistat are the perfect solutions for apples, pears, persimmon, and kiwi. And they are the only system that works at below 0 C without icing.
The FogRight atomizer has no moving parts and uses compressed air to produce "dry fog". Its large 1.5 mm orifice won't clog like pin-hole foggers. The air compressor can be placed outside of the storeroom, or it can be fed with storeroom air to maintain the proper CA mix.
And the OptiSense Humidistat uses fiber optical technology to control high humidity up to 95-98% RH - where other humidity meters get stuck. It is more accurate and more reliable at high humidity than any other RH meter on the market. It allows full outside computer control and tracking of the humidity level in the sealed Controlled Atmosphere room - every 4 minutes for the entire storage period. Settings can be monitored and changed from an outside PC to ensure ideal humidity throughout the storage period.
Reduces weight loss: High relative humidity means the surrounding air cannot hold more water vapor , so the weight of the water stays in the fruit, not evaporated into the air.
Maintains firmness: As water loss breaks down cell turgor, fruit loses firmness and skin shrivels. High humidity keeps the water in for full, firm fruit.
Increases price: Water loss and less firmness mean lower quality - and lower prices for the crop. Quality prices after storage with Optiguide's Controlled Humidity Solution pay back installation costs in the first season.
Full control and recording of RH levels and fogger activity from outside the CA room, presented as a chart or a graph.
Extends storage time: Since higher RH maintains higher quality for a longer time, there is little danger of "deteriorating rooms." Stores can hold their crop for the best market periods.
Extends shelf life: After storage, a full, firm pear or apple has a longer shelf life from grocer to consumer.
A 1000 ton CA store room can hold $200,000 of apples. If weight loss is 5% over the season, that's $10,000 evaporating into the air. A high humidity system can reduce the loss to 2%, or $4000. The $6000 system pays for itself the first year.
Even bigger savings come from high prices after storage. A 4% weight loss or shriveled skin will reduce a Class I apple to Class II, with a 30% drop in price.

The Optiguide system has been tested and used in CA facilities in northern Israel and at Stemilt Growers in the U.S.A, Washington State's leader in apples and pears.

The results of seven-month tests run in 1997 at the Post Harvest Fruit Research Lab of the Israel Fruit Growers Association appear below:
 
Kiwi, litchi, and other fruit can be stored for 6 months at -1 C to +1 C. Persimmons store well at -2C. High humidity during storage helps to preserve fresh quality and firm produce. But adding humidity to minus 0 C cold rooms runs the risk of freezing nozzles or worse: adding wet spray which will freeze into ice on the fruit. The Tabor FogRight Atomizer's "dry fog" is the perfect solution, when it is controlled by the OptiSense Humidistat.
Using supersonic compressed air, the Tabor FogRight produces micro-droplets which evaporate into the air before they reach the floor - even in -0 temperature. And the large 1.5 mm orifice in the fogger nozzle won't freeze or clog like pin-hole orifice foggers. Heating tape on the pipe system keeps the lines open, and the FogRight delivers true high humidity "dry fog" without icing the fruit.
Accurate control is necessary to provide just the proper amount of water vapor that the air can hold. The OptiSense Humidistat uses patented optical technology to control the high humidity up to 95-98% RH - where other humidity meters get stuck. It constantly senses the relative humidity in the room and electronically turns the atomizers on or off to maintain the perfect levels. The OptiSense is more accurate and more reliable at high humidity than any other RH meter on the market. It allows full outside computer control and tracking of the humidity level in the freezer - every 4 minutes for the entire storage period.
Reduces weight loss: High relative humidity means the surrounding air cannot hold more water vapor , so the weight of the water stays in the fruit, not evaporated into the air.
Maintains firmness: As water loss breaks down cell turgor, fruit loses firmness and skin shrivels. High humidity keeps the water inside for full firm fruit.
Increases price: Water loss and less firmness mean lower quality - and lower prices for the crop. Quality prices after storage with Optiguide's Controlled Humidity Solution pay back installation costs in the first season.
Full control and recording of RH levels and fogger activity from outside the CA room, presented as a chart or a graph.
Extends marketing time: Stores can hold even sensitive products to extend supply for the best market periods.
Extends shelf life: After storage, a full, firm pear or apple has a longer shelf life from grocer to consumer.
 
Dozens of storage facilities in Israel are using the Optiguide system at below 0 temperature for persimmons, kiwi, and litchi.
 
Optiguide provides Controlled Humidity Solutions for all the needs of herb growers and others shipping leafy vegetables.
After picking, fragile fresh herbs need quick cooling to maintain shelf life after transport. The Tabor FogRight Atomizer in the quick cooler speeds the cooling process and chills the herbs or lettuce to below 5 C in 4 hours. The OptiSense Humidistat controls the high humidity at 95-98% RH. This quick cooling allows herbs picked in the morning to be shipped the same day. Refrigeration in the cold chain can then continue, maintaining turgor without weight loss.
When the greens are taken out of the cooling room for packing, the Tabor FogRight Atomizer continues to add humidity to 70% RH in the packing room, ensuring that the cold and humid chain is maintained.
Certain herbs such as Basil are heated at high humidity to prevent blacking of the leaves, and to extend shelf life. Here the Tabor FogRight Atomizer can provide 98% RH even at 38 C.
Finally, the Tabor FogRight doubles as a spray treatment system. Its large 1.5mm orifice won't clog like pin-hole foggers, and its tough plastic material is not harmed by chemical sprays.
High humidity air is able to lose heat and reduce its temperature faster than dry air. Thus the chilling process is speeded up, and more water is retained in the leaves of the vegetables and herbs.
Optiguide's Tabor FogRight atomizer supplies high-humidity "dry fog" with droplets less than 10 microns in diameter. The patented technology is the acceleration chamber, which uses supersonic-speed air to atomize the water droplets. The OptiSense Humidistat uses optical technology to control high humidity up to 95-98% RH - where other humidity meters become saturated.
Quicker pre-cooling so that herbs and leafy vegetables remain fresher, and can be shipped the same day.
High RH keeps the water in the leaves, maintaining turgor for full freshness.
Longer shelf life for shipped products.
Higher quality products can reach the consumer.
The system is so effective that Agrexco, Israel's leading fresh produce exporter, now requires that all its herb growers use high-humidity quick-cooling for all their export produce. And the Tabor FogRight Atomizer and OptiSense Humidistat are leading the way.
Lettuce, cabbage, peppers, and many other vegetables benefit from quicker cooling, when high humidity is added to the quick-cool facility.
Tests using the Tabor FogRight's high humidity to speed up the pre-cooling process and increase shelf life have been carried out by Israel's Volcani Center for Agricultural Research. Their conclusion:
" a) Pre-cooling time can be reduced to 2-4 hours if the herbs are properly stacked crosswise in well-ventilated field boxes, without over-stuffing the packs. b) The pre-cooling is effective only in cold rooms equipped with a fogger producing 96-98% RH. In these conditions, there is essentially no weight loss even after 20 hours of cooling. The herbs remain fresh and vigorous."
- from "Development of Postharvest Technology to Improve Stability of Fresh Herbs intended for Export" N. Aharoni, C Chalupowicz, Z. Aharon, O. Dvir and D. Aharoni, A.R.O. Institute of Technology and Storage of Agricultural Products, 1998.
For the full research report and more information, please contact us.
Optiguide's involvement with herbs and vegetables doesn't start only after harvest. See our Controlled Humidity Solutions for Greenhouses.
 
Distribution centers for supermarkets and greengrocers face a special problem for cold storage. Arriving produce is already days from the farm and the most reliable high quality systems must be used to ensure that the cold chain is maintained to the final consumer.
Optiguide's Tabor FogRight Atomizer and OptiSense Humidistat provide the Controlled Humidity Solution to preserve quality and increase shelf life. High humidity in cold storage above 95% invigorates transported produce and presents a fresh high quality product to the consumer.
Optiguide's Tabor FogRight atomizer supplies high-humidity "dry fog" with droplets less than 10 microns in diameter. The water evaporates into the air before it reaches the ground. The Tabor FogRight has a large orifice which doesn't clog, like pinhole nozzles do. The floor stays dry, and maintenance is minimal. The patented technology is the acceleration chamber, which uses supersonic speed air to atomize the water droplets.
The OptiSense Humidistat uses optical technology to control high humidity up to 95-98% RH - where other humidity meters get stuck. It allows both independent display and full central computer control and tracking of the humidity level in the cold storage rooms.
Maintains freshness: As water loss breaks down cell turgor, fruit and vegetables lose freshness. High humidity keeps the water in, for full, firm, fresh produce.
Extends shelf life: Distribution centers can hold even sensitive products to supply stores daily and avoid product loss.
Increases price: Water loss and less firmness mean lower quality - and lower prices. Quality prices after storage with Optiguide's Controlled Humidity Solution pay back installation costs in the first season.
Higher quality produce reaches the consumer.
Israel's leading supermarket chain, Super-Sol, has used the Optiguide Controlled Humidity Solution for 3 years in their fresh produce logistical center south of Tel Aviv.