03 Jul 11 Chemistry and its role in maximising food
This is the International Year of Chemistry – thus it’s appropriate to highlight how, with the help of chemistry, we are eating safer, healthier, and more sustainable food than ever before…
Opportunities are greater than ever before for cutting-edge science to improve food and agriculture. Chemistry, in particular, can help provide a safe, healthful, and sustainable food supply to meet a growing worldwide population.
In this International Year of Chemistry, the central science should be acknowledged for its necessity in growing, developing, improving, processing, and protecting our foods. Analytical chemistry, biotechnology, and food technology join forces to help feed both developing nations and more advanced economies.
Chemistry has already helped ensure that today’s food is the safest, most affordable, and most nourishing in history. Detailed understanding of the chemical structures, stabilities, and reactivities of the essential nutrients has guided agricultural breeding, processing, and food formulations to optimize seed stability, commodities, and food products, virtually eliminating essential nutrient deficiencies.
Analytical chemistry allows detection of trace contaminants in food from deliberate or accidental adulteration, helping reduce people’s exposure to dangerous levels of pesticides, industrial chemicals, and heavy metals, and dramatically improving response to the rare exposure incidents when they occur.
“Chemistry has already helped ensure that today’s food is the safest, most affordable, and most nourishing in history.”
However, new dangers will inevitably emerge in foods, and chemists are vital to discovering and eliminating them. For example, acrylamide, a possible human carcinogen, can form when starchy foods are fried or baked. It forms when asparagine reacts with a reducing sugar in a variant of the Maillard browning reaction. The chemical sleuthing that identified acrylamide as a widespread toxicant in foods is a story unto itself (J Agric Food Chem, DOI: 10.1021/jf020302f).
Detection of acrylamide with parts-per-billion sensitivity has allowed scientists to understand its formation and to develop technologies to prevent its formation (J Agric Food Chem, DOI: 10.1021/jf0730486). Food chemists and biochemists are working with plant scientists to breed new potato varieties with low free-asparagine content that will produce less acrylamide during browning.
Scientists analyze not only produce, but the carnivore’s intake, too. During last year’s Deepwater Horizon oil spill crisis, a small army of chemists assessed the possible contamination of seafood. The oil leaking into the Gulf of Mexico contained polycyclic aromatic hydrocarbons, some of which are potential carcinogens. To date, over 300,000 animals in the Gulf have been tested, and none of the shrimp, finfish, or crabs contain the hazardous hydrocarbons at levels of concern set by the Food & Drug Administration. In fact, according to FDA, the levels fell below detection limits in the vast majority of the samples.
The rapid results from analytical laboratories allowed most fishing areas in the Gulf to reopen within four months; within a year all areas were opened. Gulf seafood is now the most tested seafood in the world. Testing continues to search for any significant residual toxicants and exposures.
Analytical food chemistry is also contributing tools for detecting the illegal contamination of food with adulterants such as melamine. In 2007 and 2008, pet foods, milk, and infant formula were illegally spiked with melamine to provide increased levels of nitrogen, making the products appear to contain more protein than was actually present. The tainted products caused kidney and urinary tract problems in domesticated animals and thousands of people. In response to the crises, regulatory agencies in many countries quickly established maximum allowable melamine levels and developed laboratory methods to measure melamine cyanurate.
Analytical chemists worldwide have been busy improving the food safety surveillance systems that protect global food supplies from melamine. Recently, researchers have developed methods suitable for rapid automated screening of a large number of samples (Anal Chem, DOI: 10.1021/ac200926e ). They have also developed methods to detect contamination in nonlaboratory settings (J Agric Food Chem, DOI: 10.1021/jf2008327).
Microbial contamination of food can also cause outbreaks of food-borne illness. Here, too, chemists play an important role. The chemistry-based tools of biotechnology enable rapid, accurate detection and identification of pathogenic bacteria.
A vivid example of the combination of biology and chemistry in the analysis of food is the polymerase chain reaction (PCR). Along with pulsed-field gel electrophoresis, PCR has brought speed and precision to researchers identifying the precise organisms that cause contamination. With these chemical tools, scientists can discover within hours whether a single microbial strain has caused multiple outbreaks that might otherwise have been viewed as an isolated incident. For instance, scientists used a sophisticated form of PCR to pinpoint a source of Escherichia coli O157:H7 in spinach originating from a single farm during a 2006 outbreak that caused product recalls in several states……