Posted by Joel Leusink on February 9, 2012 under Food Industry | 
Ozone use for the inactivation of listeria
Listeria is a common term to refer to a specific strain of bacteria species. There are seven (7) known species of Listeria. The specific species L. monocytogenes is the cause of Listeriosis, a serious infection caused by eating food contaminated with this strain of bacteria. This disease can be deadly and will pose a greater risk to those with weakened immune system. Both L. monocytogenes, and Liseteriosis, are commonly known only as Listeria, and Listeria illness.
Listeria is found in soils, this can lead to fruit and vegetable contamination. Listeria can also be found in all types of meat products, milk, and eggs. Higher risk foods are any uncooked or undercooked foods, unpasteurized milk, raw vegetables, and some ready-to-eat foods.
Click here to learn more about Listeria from the CDC (Center for Disease Control and Prevention).
Ozone can be used for the reduction, or elimination of L. monocytogenes on food products. Since achieving GRAS approval for the use of ozone for direct contact with food in 2001 the use of ozone for the elimination of L. monocytogenes has increased significantly.
To eliminate Listeria or any other bacteria with ozone successful implementation of ozone is necessary. While every application is different, there are a few fundamentals that will apply in most applications.
Implementation of Ozone
Aqueous Ozone
The most common method of using ozone for pathogen reduction is by dissolving ozone into water. Aqueous ozone is very stable, safe, and easy to manage. Typically, ozone is dissolved into water using an Ozone Injection System and then sprayed onto the surface requiring disinfection. This surface may be a hard equipment surface, or the surface of a food product.
In 2000, the Journal of Food Science published a paper by Kim & Yousef showing the effect of dissolved ozone in a batch reactor on Listeria monocytogenes. Dissolved ozone at 0.4 and 0.8 ppm inactivated 4.6 and 5.7 log CFU/ml within 30 seconds. Additional tests were run at higher dissolved ozone levels. Higher dissolved ozone levels did show faster (immediate) inactivation of Listeria monocytogenes.
Dissolved ozone can be sprayed on food and produce using spray bars, or other spraying methods. Conveyers work well to allow the sufficient contact time, and offer full coverage of the aqueous ozone. It is important that all of the produce is contacted by the aqueous ozone to achieve desired antimicrobial intervention. Contact times can be varied by altering conveyer speeds, spray tip design, and spray bar design/quantity. If water is already used in an application to wash produce it is very simple to add ozone to this water and achieve an antimicrobial intervention step without any major changes to the current processes.
Gaseous ozone
The use of gaseous ozone for the elimination of pathogens is less common. There is less research showing the effects of gaseous ozone on bacteria. The application of gaseous ozone is dependent upon the temperature, humidity, contact time, and ozone levels. Research has been conducted to determine that gaseous ozone will reduce and inactivate L. monocytogenes; however, more research is necessary to determine the effectiveness of ozone within different variables.
Produce in need of disinfection can be placed in chambers, rooms, or even cargo containers for ozone treatment. A sealed area that can contain the produce and ozone gas while maintaining human safety will work. It is necessary to assure sufficient air movement past each piece of produce. Ozone levels from 1.0 — 100 ppm are used in this application with contact times from 20 minutes to 10 hours. For more information on the potential of using gaseous ozone in your application contact our application engineers today.
Click here for more information and to view ozone research papers on this topic
Posted by Joel Leusink on February 6, 2012 under Food Industry |
Ozone use in the production of organic food
Organic food products are gaining popularity throughout the world. As concerns from potentially harmful chemicals, hormones, and other synthetic based products grow, the allure of organic foods continues to increase. Organic foods are typically foods that are grown without pesticides, herbicides, chemicals, or growth hormones. This means the food you are eating is more natural and free of synthetic products.
The National Organic Program (NOP) was established by the USDA to create rules and guidelines to ensure that organic labeled foods are truly organic. The NOP is responsible for administrating and enforcing the regulatory framework for the national organic standards. The NOP regulations cover in detail all aspects of food production, processing, delivery, and sale. There are three levels of organic foods.
- 100% Organic — Products made entirely with certified organic ingredients and methods
- Organic — Products with at least 95% organic ingredients
- Made with organic ingredients — Products containing a minimum of 70% organic ingredients
http://www.ams.usda.gov/AMSv1.0/nop
Only foods that are categorized as 100% Organic, or Organic (95%), are allowed to display the USDA Organic label on the product to consumers.
There are various regulations and rules that will dictate what ingredients can be used for organic food products. Ozone can be used in some organic applications, but not all. The regulations are sometimes hard to find and not in one central location. Below are a few locations in the organic registry where ozone is listed.
Ozone as an ingredient:
Ozone can be used as an ingredient in organic foods. However, these foods will not be able to maintain a 100% organic rating. They will only be allowed an Organic, or Made with organic ingredients label.
This information can be found in CFR 205.605
USDA wording from CFR 205.605
§ 205.605 Nonagricultural (nonorganic) substances allowed as ingredients in or on processed products labeled as “organic” or “made with organic (specified ingredients or food group(s)).”
The following non-agricultural substances may be used as ingredients in or on processed products labeled as “organic” or “made with organic (specified ingredients or food group(s))” only in accordance with any restrictions specified in this section.
Ozone is listed in this section follow link below:
http://edocket.access.gpo.gov/cfr_2011/janqtr/pdf/7cfr205.605.pdf
Ozone in crop production:
Ozone can be used in the production of crops. Ozone is considered a synthetic substance and regulated as such in crop production. Ozone is allowed for cleaning of irrigation systems only. Provided ozone is used in this manner, all crops will maintain 100% organic rating.
This information can be found in CFR 205.601
USDA wording from CFR 205.601
§ 205.601 Synthetic substances allowed for use in organic crop production.
In accordance with restrictions specified in this section, the following synthetic substances may be used in organic crop production: Provided that, use of such substances do not contribute to contamination of crops, soil, or water. Substances allowed by this section, except disinfectants and sanitizers in paragraph (a) and those substances in paragraphs (c), (j), (k), and (l) of this section, may only be used when the provisions set forth in §205.206(a) through (d) prove insufficient to prevent or control the target pest.
Ozone gas — for use as an irrigation system cleaner only.
Link to this section below:
http://edocket.access.gpo.gov/cfr_2011/janqtr/pdf/7cfr205.601.pdf
Ozone in production surface sanitation:
Ozone can be used in food processing, distribution, and retail centers as a surface sanitation on food contact surfaces. This is referenced in CRF 205.605, however it is made clear in the following document:
USDA wording from: The USDA National Organic Program Requirements for Food Retailers and Distribution Centers
The regulations identify some chlorine materials that may be used to sanitize food-contact surfaces, including calcium hypochlorite, chlorine dioxide, and sodium hypochlorite; hydrogen peroxide and ozone are also permitted. See 7 C.F.R. 205.605.
Link to this entire document below:
http://www.fmi.org/gr/USDA_OrganicProgram.pdf
These are the regulations within the NOP that contain ozone. Unfortunately at this time the USDA and the NOP have not given ozone the same latitude it has in other food processing environments similar to the GRAS approval for direct contact with food ozone was given by both the USDA and FDA. We are hopeful that in time, the USDA will allow the use of ozone in more organic applications. As ozone is produced from oxygen, and quickly returns to oxygen after oxidation of potentially deadly pathogens we feel that ozone should be given a greater role in the production of safe 100% organic foods.
Should you have any questions about the use of ozone in your organic growing application, please feel free to contact Ozone Solutions’ Application Engineers, we would be glad to discuss the potential solutions we can offer your application.
See this full webpage on our website at our organic growing with ozone page
Posted by mailman11 on January 26, 2012 under Food Industry, Ozone food |
Take a look a the FDAs following table which outlines treatment methods for controlling food related risks.
FDAs Summary of Literature Findings on Microbiological Safety Issues and Preventive Controls
Source
FDA/CFSAN, 2001c |
Industry/Products
Fresh and fresh-cut produce |
Problem/Risk
- Manure and biosolids
- Water for agricultural uses
- Improper postharvest packing, cooling, and storage practices
|
Preventive Controls Suggested
- Temperature control
- Physical removal of microorganisms
- Use of effective GRAS cleaning agents
- Ozone treatment
- Irradiation
- Biocontrol
|
It should be noted that ozone is the only oxidant specifically mentioned by name for controlling microbiological issues. It is most likely due to the fact that ozone work so well at reducing microbiological counts on produce. Applying a minimal amount of ozone in either gas or aqueous form can achieve impressive results.
To see the actual FDA document, click on the link below:
To learn more about how ozone can help you, see this food processing page.
Posted by mailman11 on January 25, 2012 under Food Industry, ozonated water, Water Remediation |
There have been a lot of question about the efficacy of ozone in warm/hot water. Yes – ozone does work in hot water! See the supporting documentation below.
- Ozone Efficacy in Hot Water – PDF
EPA Chart showing log 4 virus inactivation with ozone vs. temperature
R.N. Kinman (1975) & E. Katzenelson, et al. (1974) reported “As temperature increases, ozone becomes less soluble and less stable in water; however, the disinfection and chemical oxidation rates remain relatively stable. Studies have shown that although increasing the temperature from 0 to 30 deg C can significantly reduce the solubility of ozone and increases its decomposition rate, temperature has virtually no effect on the disinfection rate of bacteria.”
In other words, the disinfection rate was found to be relatively independent of temperature despite the reduction in solubility and reduced stability at higher temperatures.
If hot water reduces the solubility of ozone, how is Ozone Solutions addressing the lower solubility issue?
Generating high ozone gas concentrations provides better ozone mass transfer into water. We generate these high concentrations by:
- using an oxygen concentrator to provide a 90% pure oxygen feed gas to the corona cell thereby increasing the generated ozone concentration
- using a high-frequency ozone generator which can generate ozone concentrations in excess of 7% by weight
Contact Ozone Solutions at 712-439-6880 for more information.
Posted by Joel Leusink on December 23, 2011 under Food Industry |
It’s almost Christmas. Did you buy all your presents? Maybe it’s too late for last minute gift ideas, however, you can use this idea next year.
A refrigerator ozone generator makes a great give for anyone with a refrigerator. This little generator operates off 4 D cell batteries and will provide enough ozone in your fridge to keep mold and bacteria from growing. This will keep food fresh and your fridge smelling pretty!
Strawberries in a normal fridge, and a fridge with ozone for 7-days.
Learn more about ozone and food storage HERE
Wishing you and your family a very Merry Christmas. The Ozone Solutions team will be leaving now for the weekend. We will return in full force next week Tuesday.
Posted by Joel Leusink on December 3, 2011 under Food Industry, Ozone News |
Young people will compete with food safety ozone idea
(Sentinel photo by Joanne Glamm) These students use a skit to present their food safety research on pork. Portraying "pigs" concerned about their health are (from left) Chance Irwin, Claudia Probst, and Renae Zynda who listen as "reporter" Kara Albrecht interviews Morgan Boehme acting as Iowa State University researcher Dr. H. Scott Hurd.
“No more salmonella!” “No more salmonella!” chant three local young people dressed as pigs in skit with a type of Occupy Wall Street protest about food safety.
Claudia Probst, Chance Irwin and Renae Zynda, of Le Mars, are among eight young people who will showcase their research on food contamination Saturday at East High School in Sioux City.
The local students will compete in a regional tournament with other northwest and western Iowa teams by presenting a skit, demonstrating the skills of a robot and answering a challenge.
The competition is part of an international program, FIRST LEGO League.
Read full story HERE
This team met with, and toured Ozone Solutions to learn more about ozone and the potential of ozone in food safety.
To learn more about the First Lego League (FLL) click HERE
Posted by Joel Leusink on October 30, 2011 under Food Industry |
Ozone use in Milling Applications
The use of ozone in milling application has grown substantially since 1997 when ozone was first allowed in food processing applications. There are many areas of use for ozone in the milling industries and as research continues new uses will surely follow.
Overview of ozone use in milling applications
- Ozone is an oxidant used for antimicrobial and pathogen control in many food processing applications.
- Ozone was first allowed in food processing in 1997 with limited application.
- Ozone was given GRAS approval by both the FDA and the USDA in 2001.
- Ozone use in milling has been growing with ongoing research in many areas.
Applications of ozone in milling applications
There are many uses for ozone in the milling industry. While some research is on-going, below is a list of industrial applications where ozone has been used with success.
- Aqueous ozone is used in the grain temper process to inactivate mold and bacteria at the first point of the milling process.
- Ozone gas is used with dry milled product for antimicrobial intervention in process.
- Ozone gas is used for surface sanitation of enclosed equipment.
- Ozone gas is used in conveyors and transport equipment in process as an antimicrobial intervention point between process steps.
Ozone use in temper process
- The temper process adds water to the grain.
- Many grains are tempered to increase the moisture content of the grain prior to milling.
- Ozone can be dissolved into the water that is soaked into the grain.
- Most pathogens are found on the exterior of the grain.
- Fewer pathogens are found within the grain.
- Ozone use in the temper process lowers all pathogen levels in the beginning of the milling process.
Details of ozone use in temper process
Water used in tempering process passes through an ozone injection system to provide aqueous ozone at very high dissolved ozone levels. A minimum of 10 ppm of dissolved ozone is used to ensure residual aqueous ozone can soak completely through the outer later of the grain. Ozone half life in water is 20 minutes in 20-deg C water. After 60 minutes ozone level in water may still be above 2.0 ppm. Aqueous ozone at 2.0 ppm is sufficient for antimicrobial intervention. Aqueous ozone at 2.0 ppm will achieve a four (4) log reduction of bacteria in one (1) second of contact time
Ozone gas use in milling (ozone gas used on milled grain products in process)
- Sealed mixers can be used to mix ozone gas and milled grains (flour, bran, etc.)Mixers commonly used to inject chlorine gas or other chemicals could be used to apply ozone gas to the milled grain. Contact times greater than 30 seconds at ozone levels greater than 20 ppm will achieve excellent reductions in pathogens.
- Ozone can be introduced into pneumatic or mechanical conveyors to disinfect grain in processConveyers that are used to transport milled grains from one location to another can be used to apply ozone gas to the grain. This is an efficient and convenient method of applying ozone gas to the grain.
- Equipment can be sanitized by ozone gas disinfectionMilling equipment can be sealed and exposed to high levels of ozone gas. Ozone gas at effective levels for pathogen reduction can be used in these applications to safely reduce pathogens without the use of chemicals or residuals.
- Ozone gas requires more contact time and higher levels than aqueous ozone.
Practical Information
- The use of ozone in milling has shown increased reduction of bacteria, yeast, and mold reduction over time.Due to cross contamination, residual mold spores, and residual pathogens; mold and bacteria counts in the final product are not dramatically improved immediately. However, over time the mold and bacteria counts are lowered with the use of ozone in process.
- Customers have commented on reduction and complete elimination of mold growth in sifters and other equipment throughout the milling process.
- Shelf life of of some milled products has increased dramatically due to lower bacteria and mold counts.
Research
IOA User Success Report — Harvest States Amber Milling, Huron, OH
- Ozone was used in temper process to replace chlorine.
- APC bacteria reduction of 75-80% using ozone, compared to chlorine.
- After months of operation further reduction of bacteria (up to 95%) was achieved.
Influence of Tempering with Ozonated Water on the selected properties of wheat flour — Dept of Food Engineering, Univ of Gaziantep — Senol Ibanoglu (Oct 14, 2000)
- Aqueous ozone at 1.5 and 11.5 ppm were tested.
- No physical properties or baking quality changes were found.
- Statistically significant reduction in total bacteria and yeast/mold population was found at both ozone levels.
A Comparison between Chlorinated Water and Ozonated Water as an Antimicrobial Treatment during Tempering of Wheat — ASABE Meeting Presentation
- Ozonated water did not have any effect on the color and germination capacity of wheat grains.
- Ozonated water significantly lowered the yeast/mold counts in durum and hard red spring wheat.
View this application page on our website HERE
Posted by Joel Leusink on October 7, 2011 under Food Industry |
E.coli o157:H7 reduction with ozone
Bacteria is not the most common topic for discussion around workplace water coolers. However, in recent years, a specific strain of bacteria has garnered a fair amount of press and discussion. The bacterium strain E.coli O157:H7 has become so popular in the media that most people have a healthy fear of this bacteria.
Escherichia coli (E.coli) is a Gram negative bacterium that is commonly found in the intestines of animals and humans. Specific strains of E.coli are dangerous and can cause food borne illnesses. One of the most dangerous strains of E.coli is O157:H7. This strain of E.coli results in an estimated 2,100 hospitalizations annually in the United States, and can be life threatening.
This strain of E.coli can be found on many vegetables, meats, and even the water supply. Most infections from E.coli O157:57 are caused from food borne illness, mainly undercooked ground beef, however, some have been waterborne. In May of 2000, the municipal water supply of Canadian town Walkerton, Ontario, was contaminated with this pathogen and has been blamed for over 2,000 illnesses and seven (7) deaths.
Antimicrobial interventions to reduce food-borne pathogens are getting harder to find. For example, historically Chlorine has been a low cost and relatively easy to use oxidizer that is effective against a wide variety of pathogens. However, the use of chlorine is becoming more difficult to integrate as the potentially harmful side effects of chlorine are becoming more and more apparent. This is also happening with other antimicrobial interventions such as methyl bromide, chlorine dioxide, and sodium hypochlorite.
A fairly new antimicrobial intervention that is both effective and safe is ozone. The use of ozone is gaining popularity in drinking water, food processing, and surface sanitation. While ozone is effective on a wide variety of pathogens, studies were done to prove that ozone is effective against the deadly strain of E.coli O157:H7. Research has been performed and ozone has proven to be a successful antimicrobial agent in reduction of E.coli O157:H7. We have assembled a few research papers that used ozone on various food products to successfully reduce or eliminate Ecoli O157:H7. These can be found HERE.
Implementation of Ozone
Aqueous Ozone
The most common method of using ozone for pathogen reduction is dissolving ozone into water. Aqueous ozone is very stable, safe, and easy to manage. Typically, ozone is dissolved into water using an ozone injection system and then sprayed onto the surface requiring disinfection. This surface may be a hard equipment surface, or the surface of a food product.
Ozone levels of 2.0 ppm are commonly used for E.coli O157:H7 reduction. Only a few seconds of contact time of the aqueous ozone with the pathogen is necessary for inactivation. See chart below for details. Reference HERE.
Using this data a determination of spray nozzles, spray bars, or even conveyers can be established. It is clearly shown that 2.0 ppm of aqueous ozone is very effective in only a short period of time, while higher ozone levels show only marginal improvement.
Ozone can also be used in drinking water to inactivate Ecoli O157:H7. This has been confirmed by the EPA and recognized as a suitable disinfectant for water. Reference HERE.
Gaseous ozone
The use of gaseous ozone for the elimination of pathogens is less common. There is also less research showing the effects of gaseous ozone on bacteria. The application of gaseous ozone is dependent upon the temperature, humidity, contact time, and ozone levels. Research has been conducted to determine that gaseous ozone will reduce and inactivate Ecoli O157:H7, however more research is necessary to determine the effectiveness of ozone within different variables.
Ozone Solutions did perform research on the effect of gaseous ozone on ground beef to inactive E-coli. This research can be found here.
Below is an excerpt from the Direct Food Additive Petition presented to the FDA in August 2000 to achieve GRAS status for the use of ozone to inactivate Ecoli O157:h7, along with other pathogens.
To see this page on our website with additional information click HERE.
Posted by Joel Leusink on September 17, 2011 under Food Industry, Wastewater Treatment |
We recently updated our OSW-3 Ozone Injection System. This is a small ozone injection system using an ozone generator with integrated air dryer. This is a small and compact ozone injection system for use with water flows up to 10 GPM. Following are the highlights of updates:
- Improved contact tank allows for water pressures up to 50 PSI
- New CM5 Grundfos Pump
- Smaller footprint
- Integrated water trap
- Provisions for all the same optional automation as our popular Waterzone series
The OSW-3 uses a PVC mixing tank to lower costs verses our stainless steel models. The same stainless steel ozone injection pump is used on both the OSW-3 and the Waterzone Ozone Injection Systems. This ensures maximum durability of the system for the long term. In fact, many parts of these systems is same, this helps lower costs while providing a durable system.
Posted by Joel Leusink on July 11, 2011 under Food Industry |
Ozone Helps Produce Last Longer by Extending Shelf Life
Common Applications for Ozone use in Food Storage
- Potato Storage Facilities
- Onion Storage Facilities
- Citrus Fruit Storage
- Vegetable Storage
- Aged Ham Storage
- Cool Meat Storage
- Preservation of Fish and Seafood
- General Cold Storage Facilities
Methods of Ozone Application
- Ozone gas can be distributed throughout a cold storage facility at low levels.
- Ozone-sterilized ice is used to pack fresh fish and seafood to prolong freshness.
- Ozone gas is used in meat coolers to inhibit microbiological growth and extend shelf life.
- Ozone is dissolved into water to wash fruits and vegetables and remove mold and bacteria.
- Low levels of ozone gas can be used in containers to prolong shelf life upon delivery.
- Dissolved ozone is used to wash meat and poultry to remove bacteria and extend refrigerated shelf life
Benefits of Ozone Use in Cold Storage
- Extend shelf-life of the produce within the cold storage facility.
- Air-borne microbiological control
- Low ozone levels (<0.3 PPM) will inhibit microbiological growth in the air.
- High ozone levels can be used for disinfection when room is empty.
- Surface sanitation can be maintained
- By inhibiting microbiological growth pathogens on the surface of produce, containers, and walls will be kept to a minimum.
- Eliminate mold growth from cold storage area.
- Odor control
- Maintain an odor-free cold storage area
- Keep odors from cross contaminating between products
- Ethylene Removal
Extension of Storage Life With Ozone
A few examples
| Food |
Extension |
Storage Conditions |
| Fish |
50-80% |
ozone sterilized ice |
| Salmon |
50% |
ozone sterilized ice |
| Jack Mackerel and Shimaaji (fish) |
1.2 – 1.6 days |
Soak in 30% NaCl cont. 0.6 mg/L O3 30-60 min. every 2 days. |
| Beef (frozen) |
30-40% |
0.4oC; 85-90% RH; 10-20 mg/m3 O3, provided original microbial count is below 103/cm2 |
| Poultry |
2.4 days |
Soak in ice water while passing in O3 (3.88 mg/L) 20 min. |
| Bananas |
substantial |
A few ppm O3 @ 12oC, if fruit is not within a few days of its period of rapid ripening. |
| Strawberries, Raspberries, Currents, Grapes |
100% |
2-3 ppm O3, continuously or several hours each day. |
| Apples |
several |
1.95 cm3 O3/m3 |
| Potatoes |
6 months |
3 mg/L O3; 6-14oC; 93-97% RH |
| Eggs |
8 months |
0.6 ppm O3; 31oF; 90% RH |
| Cheeses |
63 days |
0.2 – 0.3 ppm O3 |
* Source: Review of the Applications of Ozone for Increasing Storage Times of Perishable Foods, Ozone: Science and Engineering, Vol. 4, pp. 147-163, 1982, Pergamon Press Ltd.
More info on food storage with ozone here
Ozone effect on pathogens
