New Chapman University study finds relatively low rates of substitution for America's favorite types of seafood

Chapman University

The seafood industry is known for its complex global supply chains and diverse market offerings, which can make accurate labeling a challenging task. Now, a new study from Schmid College of Science and Technology at Chapman University and Oregon State University offers a fresh perspective on seafood labeling practices in the United States: Substitution rates for the most popular seafood species in the U.S. remain relatively low, providing consumers with greater confidence in the seafood choices they make.

Published on January 2, 2025 (version of record) in Food Control, this study specifically examines the mislabeling rates for the top 10 most-consumed seafood products in the U.S. for the first time. These products represent nearly 80% of U.S. seafood consumption and include species such as shrimp, salmon, and canned tuna.

Led by Sarah Ahles, Christina A. Mireles DeWitt, and Dr. Rosalee S. Hellberg, the research team conducted a comprehensive meta-analysis of U.S. seafood mislabeling, drawing on 35 studies (including peer-reviewed papers, government investigations, and NGO reports) and 4,179 samples collected across 32 states. Using tools such as Google Scholar and Web of Science, the researchers conducted an exhaustive review and filtered out studies that did not meet rigorous criteria, creating the most informative dataset on U.S. seafood mislabeling to date. The dataset included fish and shellfish, with the exception of sharks, rays, and skates.

The study found that species substitution for the top 10 most-consumed seafood products in the U.S. occurred in just 13.9% of cases, far lower than the substitution rates observed for less frequently consumed species. This suggests that when it comes to popular choices like salmon, shrimp, and tuna, the issue of substitution is not as widespread as often assumed.

Substitution rates were higher for less commonly consumed species like snapper, amberjack, and halibut. However, the overall trend for America’s favorite seafood remains encouraging. For example, red snapper was substituted in 83.3% of cases, but this does not reflect the experience of everyday seafood consumers, who are more likely to purchase popular items with relatively low substitution rates.

Interestingly, mislabeling rates varied significantly across different retail settings. Restaurants exhibited a much higher mislabeling rate (55.4%) compared to grocery stores (26.2%). However, even at restaurants, species substitution for top seafoods remains relatively low. Mislabeling was more prevalent in certain product forms, with sushi and sashimi showing the highest rates at 67.5%, followed by ceviche and poke at 54.7%. Still, these product forms represent a small fraction of the overall seafood market, where the majority of consumers are less likely to face mislabeling.

The study highlights the need for better consumer education and compliance with FDA seafood labeling standards. For example, while the term “salmon” is often used generically, consumers can benefit from more specific species identification. Atlantic salmon, for instance, is primarily imported and farm-raised, whereas other varieties are largely wild-caught, suggesting the importance of clearer labeling to make informed decisions.

While the findings highlight that seafood mislabeling remains an issue—particularly for certain species and product forms—the study offers a reassuring message about the reliability of the most popular seafood choices. The low substitution rates for these products should give consumers greater confidence in their seafood choices, especially as awareness and standards improve.

Funded by the Seafood Industry Research Fund, the study calls for further research and outreach to reduce mislabeling and improve transparency within U.S. seafood markets.

 

About Chapman University

Founded in 1861, Chapman University is a nationally ranked private university in Orange, California, about 30 miles south of Los Angeles. Chapman serves nearly 10,000 undergraduate and graduate students, with a 12:1 student-to-faculty ratio. Students can choose from 123 areas of study within 11 colleges for a personalized education. Chapman is categorized by the Carnegie Classification as an R2 "high research activity" institution. Students at Chapman learn directly from distinguished world-class faculty including Nobel Prize winners, MacArthur fellows, published authors and Academy Award winners. The campus has produced a Rhodes Scholar, been named a top producer of Fulbright Scholars and hosts a chapter of Phi Beta Kappa, the nation's oldest and most prestigious honor society. Chapman also includes the Harry and Diane Rinker Health Science Campus in Irvine. The university features the No. 4 film school and No. 66 business school in the U.S. Learn more about Chapman University: www.chapman.edu.

 

Media Contact:
Carly Murphy, Public Relations Coordinator | carmurphy@chapman.edu | Desk: 714-289-3196 | Mobile: 714-497-9683

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Journal

Food Control

DOI

10.1016/j.foodcont.2024.111110 

Method of Research

Randomized controlled/clinical trial

Article Title

A meta-analysis of seafood species mislabeling in the United States

 

Chickpea and pea tempeh under development as new plant-based protein foods

UMass Amherst team will create and test new fermented food products to counteract the negative effects of Western diet

University of Massachusetts Amherst

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University of Massachusetts Amherst food scientist Hang Xiao is tackling a new challenge in his ongoing aim to develop tasty, nutritious and sustainable plant-based alternatives to animal meat. 

His new research, funded with a four-year, $387,000 grant from the USDA’s Pulse Crop Health Initiative, focuses on fermenting dry chickpeas and dry peas to create a new type of tempeh, traditionally made with soybeans. Preliminary research suggests that chickpea and pea tempeh may help offset the health risks of the Western diet, such as obesity, fatty liver, hyperlipidemia and diabetes. 

The challenge Xiao faces is uncovering the science involved in a process that’s been practiced for hundreds of years. He will use the expertise of two UMass Amherst co-investigators to carry out the research –  sensory scientist Alissa Nolden, assistant professor of food science, and John Gibbons, associate professor of food science, who uses genomic approaches to study fungi in fermented foods.

“Tempeh is a fermented, fungal food that originated from Indonesia but is now gaining popularity all around the world because it’s a good approach to producing plant-based protein food,” says Xiao, year in and year out one of the world’s most highly cited researchers, according to data analytics company Clarivate. “Tempeh fermentation is mainly done empirically without a scientific understanding of the molecular basis by which fungal fermentation impacts product functionality, such as nutritional and sensory properties and health impact. This limits our ability to develop tempeh-based meat alternatives with optimal functionalities.”

Functionality includes both taste and nutrition. For the chickpea and pea tempeh to function practically as a plant-based meat option, it needs to be tasty. 

“If it’s not tasteful, people won’t like it, and they won’t consume it frequently enough to offer health benefits,” Xiao says. “That’s one of the major challenges of plant-based protein.”

Xiao is also using “smart fermentation” in another project to develop a high-quality, plant-based protein from soybean meal, the byproduct of soybean oil extraction.

In the new project, Xiao and team will develop the tempeh products from chickpeas and peas and then “study the dynamic changes – because the fungi will be utilizing the nutrients in the peas and then transform them into different compounds. And this will have an impact on the nutritional value and the sensory properties of the final products,” he says. 

The food scientists will conduct a chemical analysis to determine which compounds, including amino acids and flavonoids, are produced during fermentation. Preliminary data suggests a nutritious high-fiber, low-fat tempeh will result.

The team will also gather a panel of consumers to rate the sensory profile of the tempeh products – their taste, smell and texture. Finally, the researchers will determine the health impact of tempeh in an obese rodent model induced by the Western diet high in animal fat and sugar, a scenario designed to mimic the way many people typically eat. 

“People consume everything mingled together,” Xiao says. “This dietary intervention is a preventive measure. We want to see if the tempeh products counteract the bad influence of the high-fat, high-sugar diet.”

Preliminary research showed promising results – that feeding obese mice chickpea tempeh did inhibit high-fat diet-induced body weight gain, fatty liver formation and negative changes in the gut microbiome, among other impacts. “These findings are important because they suggested that tempeh fermentation enhanced health benefits of chickpeas and provided a strong rationale to develop pulse-based tempeh with desirable health functions,” the grant summary concludes. 

 

Dung data: manure can help to improve global maps of herbivore distribution

University of New South Wales

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Dung is actually an important resource for millions of people worldwide. Photo: Professor David Eldridge studies herbivore dung on a field trip to Fowler's Gap

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Credit: Prof. David Eldridge

Researchers have used dung records to create high-resolution maps of herbivore distribution around the world. Their new study, recently published in Nature Food, reveals a strong positive relationship between dung presence and grazing pressure, meaning the amount of dung found in a particular location could help us understand approximately how many herbivores live there.

Many people consider dung simply as the manure left behind by horses and cows at country shows, or something to be avoided when you visit the cousins’ farm. But dung is actually an important resource for millions of people worldwide.

Dung also acts a biological footprint – it can tell us a lot about our environment, such as what animals are grazing where, and what this might mean for environmental health.

Now, scientists from Australia, Spain, China and Saudi Arabia, led by Professor David Eldridge from UNSW Sydney, have produced the first global assessment of dung produced by livestock and native grazing animals in drylands – arid and semi-arid environments that occupy about 40% of the world’s land area.

The research revealed hotspots of dung production, but also highlighted that broadly speaking, livestock and wild herbivores – animals like horses, cows and kangaroos that only eat vegetation – don’t occupy the same spaces on earth.

“Understanding where herbivores are distributed is important for a number of reasons,” says Prof. Eldridge. “It helps us to improve our understanding of the grazing industry, like the spread of bovine diseases. If we have a better understanding of where animals are, we've got a better understanding of where we might need to target particular land management practices.”

Estimating livestock density

Current assessments of livestock density are based on crude estimates of environmental variables such as mean annual rainfall, temperature, and some soil variables. These environmental variables are broad indicators of habitats that are likely to be occupied by herbivores, because more productive systems generally have more grass and therefore support more herbivores.

International organisations such as the United Nations Food and Agriculture Organisation (FAO) need to know where livestock are concentrated, and in what numbers. To do this they use relatively coarse computer models.

Improving these existing methods of predicting herbivore distribution is central to a number of agricultural industries. So, Prof. Eldridge and his team set out to solve some of these challenges with a somewhat unusual solution.

Dung – a byproduct of meat production, a source of nitrogen and phosphorus fertiliser – is used in building construction, and as a fuel for cooking by millions of people around the world. “Measuring and mapping dung could be a useful resource to help these organisations fine tune coarse predictions of animal distribution,” says Prof. Eldridge.

Methods & findings

The research team assembled 50 global datasets that included the mass of dung produced and measures of grazing pressure by different herbivores, including antelopes, sheep, and kangaroos.

Their analysis showed that all but one of these datasets showed strong positive relationships between dung production and grazing pressure.

“These data show a strong positive correlation, or positive relationship, between the amount of dung produced and animal grazing pressure,” says Prof. Eldridge. “If we know how much dung there is, then we can predict where the animals are distributed.”

The team also combined livestock and wild herbivore dung mass data from surveys at 760 dryland sites worldwide, representing independent measurements of herbivory, to generate high-resolution maps.

“The surprising thing that we found is that when you model where native herbivores are and where livestock are, there's some overlap, but in general, there are a lot of areas where they don't interact,” says Prof. Eldridge. “This could be due to direct competition for resources or avoidance by wild herbivores of potential livestock-borne parasites and diseases.”

The researchers located hotspots of dung production in central Africa, northern and eastern Australia, the Eurasian grasslands, east central India, and the west coast of the United States of America. Dung production was shown to be lower in north-central Africa and west-central China.

Dung as a scientific tool

Global assessment of livestock distribution is critically important for land use planning, for estimating gross methane emissions, predicting global meat production, or predicting where livestock may be at risk from pests and diseases such as brucellosis.

It also improves the ability of organisations to predict trends in global food production and the impacts of drought and natural disasters on food security.

Counting dung can often be easier and more efficient than counting animals, Prof. Eldridge explains.

“For example, one paper shows how dung counts often give us a better estimate of elephant densities than aerial surveys of the animals themselves. Dung counts are also efficient ways of studying habitat preference of elusive herbivores that are hard to detect or occur in very low numbers,” he says.

But dung can also help researchers at more local scales. “Knowing the location of dung in different paddocks can tell us about the habitat preference of different herbivores and how they interact. This could provide farmers with better information on where to place fences, watering points and other infrastructure to improve livestock production,” says Prof. Eldridge.

Assessments of dung are not without their complexities, Prof. Eldridge explains. “Many farmers in Asia and Africa collect dung, reducing the potential field assessment and therefore potentially underestimating the amount of dung produced by animals.”

Some animals such as deer bury their dung, and in many tropical countries, dung beetles and termites break this dung down in just a few days, making regional assessments more difficult.

“These and other issues make it difficult to come up with robust assessments of animal densities,” says Prof. Eldridge. “However, even when we accounted for areas where people collected dung, there was still strong relationships with grazing pressure.”

Despite the challenges, this research provides a world-first, comprehensive global map of the dung of livestock and wild herbivores in drylands, and paves the way for organisations to incorporate dung data into livestock maps and models.

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Journal

Nature Food

DOI

10.1038/s43016-024-01112-9 

Method of Research

Data/statistical analysis

Subject of Research

Not applicable

Article Title

Dung predicts the global distribution of herbivore grazing pressure in drylands

Article Publication Date

14-Jan-2025

 

Volcanic eruption caused Neolithic people to sacrifice unique "sun stones"

Archaeologists and climate scientists from the University of Copenhagen can now show that ritual sacrifices of sun stones coincided with a large volcanic eruption hat made the sun disappear throughout Northern Europe.

University of Copenhagen - Faculty of Humanities

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Two so-called sun stones, which are small flat shale pieces with finely incised patterns and sun motifs. They are known only from the island of Bornholm in the Baltic Sea

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Credit: National Museum of Denmark

Throughout history, volcanic eruptions have had serious consequences for human societies such as cold weather, lack of sun, and low crop yields. In the year 43 BC when a volcano in Alaska spewed large quantities of sulphur into the stratosphere, harvests failed the following years in the countries around the Mediterranean, causing famine and disease. This is well-documented in written sources from ancient Greece and Rome. 

We do not have written sources from the Neolithic. But climate scientists from the Niels Bohr Institute at the University of Copenhagen have analysed ice cores from the Greenland ice sheet and can now document that around 2,900 BC a similar volcanic eruption took place. An eruption that must have had equally devastating consequences for the Neolithic peoples who lived in Northern Europe at the time and who were deeply dependent on agriculture.  

This new insight into a climate episode in the Neolithic period has led archaeologists from the University of Copenhagen, the National Museum of Denmark and the Museum of Bornholm to view their findings of so-called "sun stones" from the Neolithic Vasagård site on Bornholm in a new light, and they have just published a scientific article on the phenomenon in the journal Antiquity:

"We have known for a long time that the sun was the focal point for the early agricultural cultures we know of in Northern Europe. They farmed the land and depended on the sun to bring home the harvest. If the sun almost disappeared due to mist in the stratosphere for longer periods of time, it would have been extremely frightening for them,” says archaeologist Rune Iversen from the University of Copenhagen, who has participated in the excavations at the site led by the Museum of Bornholm and the National Museum. He adds:  

“One type of find that is completely unique to Bornholm is the so-called sun stones, which are flat shale pieces with engraved patterns and sun motifs. They symbolized fertility and were probably sacrificed to ensure sun and growth. Sun stones were found in large quantities at the Vasagård West site, where residents deposited them in ditches forming part of a causewayed enclosure together with the remains of ritual feasts in the form of animal bones, broken clay vessels, and flint objects around 2,900 BC. The ditches were subsequently closed.”   

Rune Iversen and his colleagues believe that there is a very high probability that there is a connection between the volcanic eruption, the subsequent climate changes and the discovery of the ritual sun stone sacrifices.

“It is reasonable to believe that the Neolithic people on Bornholm wanted to protect themselves from further deterioration of the climate by sacrificing sun stones – or perhaps they wanted to show their gratitude that the sun had returned again.”

Major cultural changes
As if an acute climate deterioration around 2,900 BC was not enough, Northern European Neolithic cultures were also affected by other disasters; New DNA studies of human bones have shown that the plague was very widespread and fatal.

During the same period when the Neolithic people were affected by both climate change and disease, archaeologists can also document a shift in the traditions they had held on to for a long time. The so-called Funnel Beaker Culture, which had been dominant until about 5,000 years ago with its characteristic ceramics and passage graves, was gradually disappearing. 

“At the causewayed enclosure we have excavated on Bornholm, we can also see that, after the sacrifice of the sun stones, the residents changed the structure of the site so that instead of sacrificial ditches it was provided with extensive rows of palisades and circular cult houses. We do not know why, but it is reasonable to believe that the dramatic climatic changes they had been exposed to would have played a role in some way, Rune Iversen concludes.   

Sun stones to be exhibited in Copenhagen
Four of the sun stones from Vasagård on Bornholm can be experienced from 28 January in the prehistoric exhibition at The National Museum of Denmark in Copenhagen. They probably exemplify one of the earliest depositional practices connected to a Neolithic sun-cult in South Scandinavia, which are also known from the Nordic Bronze Age with objects like the sun chariot.

"The sunstones are completely unique, also in a European context. The closest we get to a similar sun-cult in the Neolithic is some passage graves in southern Scandinavia or henge structures like Stonehenge in England, which some researchers associate with the sun. With the sun stones, there is in my mind no doubt. It is quite simply an incredible discovery, which demonstrates that depositions honouring the sun is an ancient phenomenon, which we encounter again in South Scandinavia during the climate disaster caused by a volcanic eruption in the year 536 AD, where several large gold hoards were deposited as sacrifices,” says Lasse Vilien Sørensen,  who is senior researcher at The National Museum of Denmark and co-author of the research paper.

Volcanic eruption 2,900 BC
The researchers can document reduced radiation from the sun and consequent cooling, which can be traced in both the United States and Europe around 2,900 BC. 

Dendrochronological analyses of fossil wood show signs of frost in the spring and summer months both before and after 2,900 BC.

And ice cores from the Greenland ice cap and the Antarctica contain sulphur, which is a sign of the occurrence of a strong volcanic eruption.

The archaeological site Vasagård is located on Bornholm in the Baltic Sea 

Credit

University of Copenhagen

Journal

Antiquity

DOI

10.15184/aqy.2024.217 

Method of Research

Observational study

Subject of Research

Not applicable

Article Title

Sun stones and the darkened sun: Neolithic miniature art from the island of Bornholm, Denmark

Article Publication Date

16-Jan-2025

 

Asteroid impact sulfur release less lethal in dinosaur extinction

Vrije Universiteit Brussel

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Approximately 66 million years ago, the Chicxulub asteroid, estimated to be 10-15 kilometer in diameter, struck the Yucatán Peninsula (in current-day Mexico), creating a 200-kilometer-wide impact crater. This impact triggered a chain reaction of destructive events including a rapid climate change that eventually led to the extinction of the non-avian dinosaurs and in total about 75% of species on Earth. The main culprit is most likely the “impact winter”, which was caused by massive release of dust, soot, and sulfur into the atmosphere, leading to extreme cold, darkness, and a collapse in global photosynthesis, with lasting effects on ecosystems for years to decades after impact.

Most previous studies considered sulfur as the most crucial factor in driving the cooling and extinction after the impact event. However, estimates of the volume of sulfate aerosols released from the vaporization of the impacted rocks in Mexico have varied widely over two orders of magnitude from one study to another. This is because such estimates are largely based on uncertain parameters, such as the proportion of sulfur-bearing rocks at the impact location, the size, velocity, and impact angle of the asteroid, and the resulting shock pressures of sulfur-bearing minerals.

In the new study, Katarina Rodiouchkina and colleagues used sulfur concentrations and isotopic compositions from new drill cores of impact rocks within the crater region, combined with detailed chemical profiles across K-Pg boundary sediments around the world. This way, the authors were able to empirically estimate, for the first time, the total amount of sulfur released into the atmosphere due to the Chicxulub asteroid impact event.

“Instead of focusing on the impact event itself, we focused on the aftermath of the impact “, explains chemist Katerina Rodiouchkina. “We first analyzed the sulfur fingerprint of the rocks within the crater region that were the source of sulfate aerosols released into the atmosphere. These sulfate aerosols distributed globally and were eventually deposited from the atmosphere back onto the Earth’s surface in the months to years after impact. The sulfur was deposited around the K-Pg boundary layer in sedimentary profiles all over the world. We used the corresponding change in the isotopic composition of sulfur to distinguish impact-related sulfur from natural sources and the total amount of sulfur released was calculated through mass balance.“

The scientists revealed that a total of 67 ± 39 billion tons of sulfur were released, approximately five times less than previously estimated in numerical models. This suggests a milder "impact winter" than previously believed, leading to a less severe temperature decline and faster climate recovery, which could have contributed to the survival of at least 25% of species on Earth following the event. While sulfur remains the primary driver of global cooling, it is important to note that a recent study by the Royal Observatory of Belgium and VUB suggests a massive plume of micrometer-sized fine dust may have played a crucial role in creating a two-year-long dark period, blocking photosynthesis and further compounding the environmental impacts.

The study was a collaboration between Luleå University of Technology, Ghent university (UGent), Vrije Universiteit Brussel (VUB), Royal Observatory of Belgium (ROB), Université Libre de Bruxelles (ULB), Leibniz-Institute for Baltic Sea Research Warnemünde (IOW), University of Greifswald, University of Rostock, Australian Laboratory Services (ALS) Scandinavia AB, Katholieke Universiteit Leuven (KU Leuven), and the Royal Belgian Institute of Natural Sciences (RBINS). This research was supported by the Research Foundation Flanders (FWO) through the EOS-Excellence of Science program (project ET-HoME) and Hercules funding for the acquisition of a multi-collector ICP-mass spectrometer at UGent, VUB Strategic Research Program, Chicxulub BRAIN-be (Belgian Research Action through Interdisciplinary Networks) and the FED-tWIN project MicroPAST both through the Belgian Science Policy Office (BELSPO).

 

Reference:

Katerina Rodiouchkina, Steven Goderis, Cem Berk Senel, Pim Kaskes, Özgür Karatekin, Michael Ernst Böttcher, Ilia Rodushkin, Johan Vellekoop, Philippe Claeys, Frank Vanhaecke. Reduced contribution of sulfur to the mass extinction associated with the Chicxulub impact event. Nature Communications (2025). DOI: 10.1038/s41467-024-55145-6

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Journal

Nature Communications

DOI

10.1038/s41467-024-55145-6