Module 6: Technological Innovations to Improve Food Safety

Early Technologies

The practices of pasteurization and canning foods were both implemented as early as the 19th century. Canning was widely practiced to preserve food at this time, though 19th century methods were not standardized. This likely contributed to the global disease burden, as improper canning increases the risk of botulism, a paralytic disease resulting from ingesting the potent botulinum toxin produced by the bacterium Clostridium botulinumunder certain anaerobic conditions. Through sufficient heating (to kill the bacterium) and proper canning, canned foods should not contain botulinum toxin, and thus should not cause botulism.(1)

Pasteurization was similarly practiced beginning in the 1800s. Near the turn of the century, people began to realize that milk was the source of many infections, including typhoid fever, bovine tuberculosis, diphtheria, and streptococcus.(2) A method conceived by Louis Pasteur, pasteurization kills harmful bacteria through the application of heat.

Recent Technological Innovations

Many different variations of pasteurization have been invented to treat a variety of foods. Steam pasteurization passed 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 a pressure of 87000 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.(4) 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.(5)

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 FAO, there is significant evidence suggesting that no amount of washing will get rid certain produce of all organisms.(6)

Perhaps the biggest new, 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. This kills the bacteria, rendering them unable to reproduce. Studies have shown that irradiation is effective in controlling bacteria, such as E. coli, on seed sprouts.(7) 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:

 

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.(8)

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.(9) 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.(10) 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.(11) 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(12)
Description: Radura symbol (stylized flower inside broken circle)

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.(13) 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.(14) 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.(15)  

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.(16) 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.(17)

Go To Module 7: Case Studies: Health and Environmental Impacts of Specific Foods >>

Footnotes

(1) Tauxe RV. Food safety and irradiation: protecting the public from foodborne infections. Emerg Infect Dis 2001; 7(Suppl):516–21.

(2) Ibid.

(3) Majchrowicz A. Innovative technologies could improve food safety. Food Review USDA 1999;22:16-20.

(4) Stevens, Shawn. "High Pressure Processing Continues To Show Incredible Promise.”www.defendingfoodsafety.com. Gass Weber Mullins LLC, 21 Oct. 2010. Web. 23 May 2012.

(5) Majchrowicz A. Innovative technologies could improve food safety. Food Review USDA 1999;22:16-20.

(6) FAO. "Food Irradiation - a Better Way to Kill Microbes Associated with Food Borne Illness." www.fao.org. FAO, 14 June 2011. Web. 23 May 2012.

(7) Ibid.

(8) Ibid.

(9) "Food Irradiation." www.cdc.gov. Centers for Disease Control and Prevention, 11 Oct. 2005. Web. 05 June 2012.

(10) Tauxe RV. Food safety and irradiation: protecting the public from foodborne infections. Emerg Infect Dis 2001; 7(Suppl):516–21.

(11) USDA. "Irradiation and Food Safety Answers to Frequently Asked Questions." www.fsis.usda.gov. United States Department of Agriculture, 23 Mar. 2012. Web. 23 May 2012.

(12) UW Food Irradiation Education Group. The Facts. UW Food Irradiation Education Group. uw-food-irradiation.engr.wisc.edu. Web. 25 May 2012.

(13) Majchrowicz A. Innovative technologies could improve food safety. Food Review USDA 1999;22:16-20.

(14) BioMérieux Industry. "BioMérieux Launches Groundbreaking Salmonella Detection Technology to Improve Food Safety." www.biomerieux.com. 11 June 2011. Web. 23 May 2012.

(15) "VIDAS UP Salmonella." www.biomerieux-industry.com. BioMérieux Corporate, 4 June 2012. Web. 05 June 2012.

(16) New Desk. "Investment Awards for Two Food Safety Technologies.”www.foodsafetynews.com. Food Safety News, 23 Feb. 2012. Web. 23 May 2012.

(17) Ibid.