Processed food rethink? Researchers call for plant-based product reclassifications

Researchers have challenged current processed food classification systems, suggesting that prioritizing biochemical composition and the nutritional value of plant-based foods like tempeh and soy chunks that retain soybean phytochemicals is more effective.

The study from the University of Turku, Finland, shows how various processing methods impact the nutrition of plant-based foods since many of them are classified as ultra-processed. However, it reveals that this label does not reflect the nutritional potential of such foods. 

Nutrition Insight speaks to Kati Hanhineva, professor of Food Development, and Jasmin Raita, doctoral researcher at the university, who call for new food classifications that prioritize biochemical composition over processing techniques. They believe this would provide a healthier and more accurate understanding of plant-based diets.

“Phytochemicals could indicate how well the original composition of the plant-based raw material has been preserved,” says Hanhineva. “If there are no phytochemicals left in the product, it indicates that the product has undergone heavy industrial processing, after which the biochemical composition is completely different from that of the original plant used as a raw material.”

Ultra-processed labels bring confusion

The researchers discuss the dangers to consumer trust and public health messaging of current food classification systems that incorrectly label nutrient-rich fermented products as ultra-processed.

Current food classifications ignore key health-promoting compounds like phytochemicals.“The term ‘ultra-processed’ can be confusing for consumers, as that food category may include products with possible health benefits as well as products with negative health impacts. Moreover, even the categorization of the different foods is subject to errors and has proven to be difficult even for scientists, let alone consumers,” says Hanhineva.

“Often the negative health effects of ultra-processed foods are associated with consuming sugar- or artificially-sweetened drinks and pastries, for example. However, due to the lack of consistency within this classification system, some nutrient-rich products, such as tempeh, are also categorized as ultra-processed even though there are no reported negative health impacts related to their consumption.”

According to Raita, this causes confusion because, although the classification system advises against eating ultra-processed foods, consumers are unsure of what these foods are or what ultra-processing is in general. 

“Based on these existing systems, plant-based foods are often classified as ultra-processed, which might lead consumers to avoid them, even if there is no scientific reason.”

Discarding healthy versus processed duality

The researchers describe how prioritizing phytochemical content over processing categories changes perceptions of healthy versus processed foods.

Fermented foods like tempeh still pack powerful nutrients, even if labeled “ultra-processed.”“Food processing is not a bad thing, and it does not make food products unhealthy. If we would focus on the phytochemical composition instead of these processing categories, then it would be clearer to see the impact of the used processing technique on the biochemical composition of the raw material and its nutritional value,” comments Raita.

“Often, the term processed already has a negative nuance, and by focusing on the phytochemical composition, it could be improved to a more positive tone. The whole ‘healthy’ versus ‘processed’ setup should be discarded, as not all natural products are healthy, and not all processed foods are unhealthy.”

The focus should be on the product’s nutritional makeup and quality, where the phytochemical content is also important, according to Hanhineva. The processing method itself has no effect on human health.

She affirms that fermentation can enhance nutrient availability. “The impact of processing on the product depends on the technique used. Fermentation is a great example of a processing technique that can improve nutritional qualities.”

“It would also be beneficial to acknowledge other processing techniques that can improve the biochemical and nutritional compositions of foods, to distinguish them from techniques that degrade bioactive compounds.”

The study, published in Nature Food, focused on soy-based products and their isoflavonoids. It found that processing methods changed the levels of isoflavonoids in the food. Foods made from protein concentrates or isolates, like plant-based burger steaks, ended up with low isoflavonoids. However, lightly processed foods, like tofu and soy chunks, retained a high level of isoflavonoids from the original soybean.

Demand can drive regulation 

The researchers discuss the regulatory and industrial obstacles to incorporating biochemical composition into food labeling and classification.

“Different countries have different regulations related to what can be presented in food labels,” says Hanhineva. “To include the biochemical composition of a product in food labeling, it would require the corresponding analysis of the food product, and for phytochemicals, there are not yet validated methods available.” 

Not all processing is bad — some methods, like fermentation, boost nutritional value.However, Raita notes these methods could be developed quickly if consumer interest in these compounds surges, which would pressure industry and regulatory organizations to disclose the food’s biochemical makeup on labels.

Improving biochemical richness

The researchers offer suggestions on how the industry can preserve or improve the biochemical richness of plant-based foods while balancing convenience, shelf life, and taste.

Raita takes fermentation as an example, as it can be used to “improve shelf life, as well as the sensory properties of plant-based foods, while enhancing their biochemical compositions.” 

“Other processing techniques that would preserve the phytochemicals could also be used. By using the whole plant material, industries could develop products that are convenient to eat and would still include the bioactive compounds present in the raw material.”

Hanhineva adds that various spices and herbs could help create delicious plant-based foods, which would enhance their flavor and include bioactive compounds. “In general, it should be seen as an opportunity for the industry to develop new products by choosing such food technological processes that enable preserving the biochemical richness of the food.”

“Highly processed plant-based protein-rich foods have been on the market for such a short time that it is too early to say anything for certain about the healthiness of all processed plant-based products as a whole, but research on this topic is active.” 

However, she notes that in population-based epidemiological studies, phytochemical-rich food groups are generally considered healthy, whereas phytochemical-poor food groups usually do not contain them. “Therefore, it is justified that the range of phytochemicals should be better recognized in categorizing foods.”

Previously, we spoke to Frank Jaksch, CEO of Ayana Bio, about how plant cell culture technology could reshape the future of processed foods, making them healthier without compromising taste or accessibility.