Module 6: Technological Innovations to Improve Food Safety

Early Technologies

Canning and pasteurization are methods for preserving foods that have been used since  the 19th century. Because canning methods were not standardized, it is thought that improper practices may have contributed to the global disease burden. Improper canning increases the risk of botulism, a paralytic disease resulting from ingesting the potent botulinum toxin produced by the bacterium Clostridium botulinum under certain anaerobic conditions. For this reason it is essential to use proper canning techniques so that bacteria are not able to grow and the food is safe for human consumption.(1)

Pasteurization was similarly practiced beginning in the 1800s. Near the turn of the century, people began to suspect that milk was the source of many illnesses, including typhoid fever, bovine tuberculosis, diphtheria, and streptococcus.(2) Pasteurization is a method developed by Louis Pasteur that uses heat to kill harmful bacteria in food.

Recent Technological Innovations

Many different variations of pasteurization have been invented to treat a variety of foods. Steam pasteurization passed United States Department of Agriculture (USDA) approval for use on beef in 1995. In steam pasteurization, slaughtered (and washed and trimmed) beef carcasses are exposed to pressurized steam for 6 to 8 seconds, which raises the temperature of the carcass to 190-200°F.(3) High-pressure pasteurization (HPP) relies on ultra-high pressure (UHP) technology. Exposing foods (often in their final packages) to UHP water jets that apply up to 87,000 psi for up to 3 minutes destroys pathogens and microbes that spoil the food. This process does not affect the taste, appearance, or nutritional value of the food, nor does it compress the product. UHP water jets can also be used to cut food, such as chicken, fish, and pizza. Cutting food using UHP water jets, instead of traditional knives, decreases the risk of cross-contamination between foods.(4)

Irradiation

Even with strict food production standards, there is no way to ensure that food is completely safe and free of all organisms. In fact, according to the Food and Agriculture Organization of the United Nations (FAO), there is significant evidence suggesting that no amount of washing will get rid certain produce of all organisms.(5)

Perhaps the most significant, non-thermal innovation in food safety is irradiation. Food irradiation uses electron beams, X-rays, or gamma rays to kill bacteria without damaging the produce. High-energy beams do not affect produce, but do damage the DNA of living organisms and kills the bacteria. Studies have shown that irradiation is effective in controlling bacteria, such as E. coli, on seed sprouts.(6) When used in addition to conventional food safety practices (e.g. washing, packaging, heat or chemical treatments, and refrigeration or freezing), irradiation can ensure higher food quality and safety. Irradiation also has the following advantages over conventional food safety practices:

• It does not raise the temperature of the food significantly, and thus does not “cook” the food

• Unlike freezing, it does not produce ice-crystals that affect the food’s texture

• Unlike chemical treatments, it does not leave potentially harmful residue

• It can be used in addition to packaging food, so that food remains safe from contamination after treatment

Irradiation thus has the potential to deal with virulent pathogens that can withstand conventional practices, as occurred with the E. coli outbreak in 2011 that killed 26 people and infected 2,000 more in Europe.(7)

Food that has been treated with irradiation is generally considered safe and not radioactive, because the source of radiation never touches the food, and the energy passes through the food. Irradiating food does not change the nutritional value of the food.(8) In fact, consumers can only distinguish irradiated foods by the presence of the international symbol for irradiation, not by appearance, taste, touch, or smell. Multiple studies have been conducted on the effects of irradiated food on animals, and none has demonstrated ill effects.(9) As a result, irradiation is deemed safe by the WHO, CDC, USDA, and FDA. Today, irradiation is used on more than 40 food products in over 37 countries.(10) In the United States, products approved for irradiation include fruits, vegetables, spices, raw poultry, red meats, wheat, and flour. NASA even provides astronauts with irradiated meat.

Figure: International symbol for irradiated foods.(11)

Ozone

Ozone (O3) is used as a disinfecting agent, often to treat municipal water supplies. Ozone can be used in its gaseous or liquid state. Gaseous ozone can be used as a cleansing agent for water-sensitive products, such as berries. Ozonated water is effective in eliminating pathogens on the surfaces of meat, poultry, and vegetables.(12) However, ozone disinfection systems remain costly—aqueous ozone systems used by large poultry operations cost $150,000, while smaller systems cost $25,000.

Newer Innovations

Another less recognized and more recent technological innovation aimed at improving food safety was developed by bioMérieux, a company specializing in in vitro diagnostics. In 2011, bioMérieux developed a food safety testing method, VIDAS® UP Salmonella (SPT). SPT uses recombinant bacteriophage proteins to detect low levels of salmonella bacteria contamination in food and environmental samples.(13) The use of phage recombinant proteins allows for highly specific targeting of the pathogen. The basic mechanism behind the VIDAS technology involves antibodies capturing the target pathogen and then fluorescing, the intensity of which is subsequently detected.(14)

Just a few months ago, two technological innovations were given investment awards. One technology is nanoRETE, Inc., which uses nanoparticle biosensors for real-time detection of pathogens. nanoRETE uses a handheld device to screen for numerous pathogens and toxins, including anthrax, E. coli, salmonella, and tuberculosis.(15) Seattle Sensors Systems Corporation uses a portable surface plasmon resonance (SPR) technology to detect biohazards in food and in the environment. This technology is also embedded in a portable device and is targeted for use in monitoring production and analyzing factory environments for hazards.(16)

Footnotes

(1) Tauxe, R. "Food Safety and Irradiation: Protecting the Public from Foodborne Infections." (2001) Centers for Disease Control and Prevention. https://wwwnc.cdc.gov/eid/article/7/7/01-7706.

(2) Ibid.

(3) Majchrowicz A. “Innovative technologies could improve food safety.” Food Review USDA 1999;22:16-20. http://ageconsearch.umn.edu/record/266213/files/FoodReview-216.pdf.

(4) Ibid.

(5) Joint FAO/IAEA Programme Division of Nuclear Techniques in Food and Agrigulture. "Food Irradiation - a Better Way to Kill Microbes Associated with Food Borne Illness." (2017) http://www-naweb.iaea.org/nafa/news/food-irradiation.html.

(6) Ibid.

(7) Ibid.

(8) Tauxe, R. "Food Safety and Irradiation: Protecting the Public from Foodborne Infections." (2001) Centers for Disease Control and Prevention https://wwwnc.cdc.gov/eid/article/7/7/01-7706.

(9) Ibid.

(10) USDA. "Irradiation and Food Safety Answers to Frequently Asked Questions." (December 20, 2016) https://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/production-and-inspection/irradiation-and-food-safety/irradiation-food-safety-faq.

(11) UW Food Irradiation Education Group. “The Facts.”https://uw-food-irradiation.engr.wisc.edu/Facts.html.

(12)  Majchrowicz A. “Innovative technologies could improve food safety.” Food Review USDA 1999;22:16-20. http://ageconsearch.umn.edu/record/266213/files/FoodReview-216.pdf.

(13) BioMérieux. "BioMérieux Launches Groundbreaking Salmonella Detection Technology to Improve Food Safety." (June 22, 2011) https://www.biomerieux-usa.com/biomerieux-launches-groundbreaking-salmonella-detection-technology-improve-food-safety.

(14) BioMérieux. "VIDAS UP Salmonella." https://www.biomerieux-usa.com/sites/subsidiary_us/files/doc/vidas-up-flow-chart-8.pdf.

(15) News Desk. "Investment Awards for Two Food Safety Technologies.” (February 23, 2012) https://www.foodsafetynews.com/2012/02/battle-creek-food-safety-tech-accelelerator-awards-investments/. Food Safety News.

(16) Ibid.