FDA sensory analyst William Parsons sniffs a sample of canned mackerel to check for spoilage. Get this and other FDA sensory analysis and entomology photos on Flickr.
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At a Food and Drug Administration laboratory in Jefferson, Arkansas, sensory analysts’ noses—not their microscopes—are their essential tools. These specialists in this FDA regional lab use their sense of smell for detecting odors of decomposition to make sure domestic and imported seafood and seafood products are fit for consumption. These analysts are part of the lab’s food filth team, which includes entomologists (those who study insects) and a filth and sanitation specialist. The team investigates a host of other food products to test for contamination.
All of their tasks are an important part of the agency’s work under the Federal Food, Drug, and Cosmetic Act, which protects the public from food that’s filthy, putrid or decomposed, or is in any other way harmful to human health. While FDA uses a wide range of sophisticated tools and technologies to protect the food supply, the power of the human nose cannot be underestimated.
“You always hear, ‘If it smells like fish, don’t eat it,’” says FDA sensory analyst William Parsons, standing in the modern Arkansas lab. “For the lay person, that’s good advice. But for us analysts, we have to codify it a bit more. We have to know which specific odors indicate spoilage and which don’t. For instance, ‘fishy,’ for us, means ‘low quality’ in most fish, but it’s a natural odor for several species like sardines or herring.”
Parsons and other FDA sensory analysts undergo thorough training to learn how to sniff out spoilage or contaminants such as petroleum products in seafood and seafood products.
“Odor memory is one of the strongest recollections that humans have,” Parsons explains. He relies on it to recognize, for example, sulfurous, sour or fruity odors that signal decomposition in fish. But he also knows that a rice-like or briny smell in shrimp is typical of high-quality product.
Parsons and his colleagues also do chemical testing for histamine, a byproduct of spoilage in certain species of fish such as tuna or mahi-mahi.
“While we also perform sensory analysis on samples of these species, it’s essential that we determine how much, if any, histamine is present in those samples, as scombrotoxin poisoning is potentially dangerous to people sensitive to histamine,” he explains.
FDA sensory analysts often work in teams of two to determine which samples can move forward and which need to be rejected. The lab’s regulatory work must be precise and beyond reproach if challenged in a court of law. And ensuring that products are safe remains paramount.
It may be off-putting to know, but so-called “filth” can get into our foods during the growing, manufacturing and shipping process. Insect parts, other foreign substances or mold can have many sources, and we often don’t even see them. These substances may be present in food naturally and unavoidably, or as the result of intentional or unintentional bad practices. The identification and confirmation of filth can help determine how the material got into a product. Even more importantly, the analysis helps FDA scientists determine whether a food item carries a potential health risk.
In addition to sensory analysts, ORA labs are staffed by entomologists and other analysts who test imported and domestic foods for contaminants. These food samples are collected during inspections of food manufacturing and storage facilities, or through targeted/random collections at border crossings.
“With world commerce, food items come into the United States from all over the world,” explains FDA entomologist Howard G. Semey. So FDA remains ready to ensure that these items meet U.S. standards for sanitation, identity and labeling according to the law.
Semey and the filth team examine everything from packaging to the foods themselves to search for safety issues. Their work is vital, particularly because some contaminants such as certain insects (and even traces of these items) can carry diseases and bacteria.
It is nearly impossible to grow, harvest or process raw products that are totally free of non-hazardous, naturally occurring defects. Recognizing this, FDA has set maximum allowable limits for these defects (Food Defect Action Levels). Above those limits, the food is considered adulterated. And defects that are harmful to the consumer are not allowed at any level.
FDA takes actions to prevent adulterated products from reaching consumers whether they are domestic or imported.
Agency staff also examine labels to make sure manufacturers aren’t making unsubstantiated health claims or giving consumers false or misleading information.
Fish and shellfish contain high-quality proteins and other essential nutrients, and a well-balanced diet that includes a variety of fish and shellfish can contribute to heart health and aid in children’s proper growth and development. To guard against spoilage and contamination in your own home, follow FDA’s tips for seafood safety.
This article appears on FDA’s Consumer Updates page, which features the latest on all FDA-regulated products.
November 12, 2014