Alternative proteins are rapidly becoming popular, globally, due to their purported health benefits, lower environmental impact and leaning more towards animal welfare in comparison with conventional sources. Such ‘friendly’ proteins include those derived from newfound sources such as plants, algae, fungi, and insects. They also include new approaches such as fermentation, plant-based meat or dairy, cultured meat, among others. Despite the surge in interest towards these protein sources, understanding the food safety risks associated with them is imperative, to say the least.
Plant proteins and plant-based meat products
Due to the allergenicity of soya protein and the requirement for label declaration on food products containing soya, demand for its alternatives, including pea protein, has increased in recent years. There is no requirement for pea protein to be identified as allergen on food labels in most countries. However, a recent report reveals that pea derived ingredients in food products may be a relatively under-recognised source of allergy and anaphylaxis. The report suggests that high doses of protein in pea protein concentrates (60-70 per cent) and isolates (70-95 per cent) may increase the chance of systemic reactions from small amounts of food ingested. Although studies suggest that cooking/ processing decreases the IgE-binding capacity for legume allergens, the effect of cooking/ processing needs to be studied on the food products with pea protein isolate containing much higher amounts of protein than cooked peas.
Individuals allergic to peanut and soy may also experience reactions to pea and lupin protein. Lupin is a legume belonging to the same family as peanuts and so people allergic to peanuts may also react to lupin. Lupin has a history of consumption in some parts of the world, however European Food Safety Authority (EFSA) and Food Standards Australia New Zealand (FSANZ), formerly Australia New Zealand Food Authority, have made it mandatory to declare lupin as allergen in EU and Australia and New Zealand respectively. The United States Food and Drug Administration (US FDA) is actively monitoring complaints of allergic reactions to lupin in US consumers. Although allergen labelling is not required for lupin in the USA, they must still be declared by name in the list of ingredients on the label for consumers to be aware of this ingredient.
Novel plant proteins may also pose other food safety challenges such as microbial and chemical contamination as prevalent in conventional and animal protein sources. A recent study reported a high prevalence (32 per cent) of Clostridium botulinum in 74 samples of plant-based sausages from seven producers in Europe.
The plant protein sources may also face the challenge of chemical contamination such as pesticide residues, mycotoxins, heavy metals depending on the land & water use, agronomic practices, and the surrounding environment. For instance, duckweed (water lentil) has GRAS status based on safety assessment; however, it may still pose potential food safety hazards like heavy metals due to environmental contamination of water resources.
Microalgae like Spirulina & Chlorella have been in use as a source for single cell protein for several decades and the interest in other algal species as protein source is growing. Chemical and toxin contamination are the major safety risks associated with microalgae as a single cell protein source. Environmental contamination of water sources used for microalgal cultivation can lead to uptake and accumulation of heavy metals or pesticide residues in microalgal cells. Environmental cross-contamination with toxin-producing cyanobacteria like Microcystis aeruginosa may result in accumulation of toxins in cells. The allergenicity of new strains or other non-cyanobacterial species needs to be further studied before considering them as protein sources.
Some species of filamentous fungi produce mycoproteins and the one produced with Fusarium venenatum is currently used in foods with brand name Quorn. Post safety and toxicity assessment of mycoprotein, Quorn has the FDA GRAS status. With growing interest in fermentation-based approaches for protein production, fungal sources are also receiving growing interest. The key food safety risks associated with fungal proteins/ mycoproteins are allergens and mycotoxins. There are reports of mycoprotein/ Quorn products causing allergic and gastrointestinal reactions. Studies also suggest that mycotoxin production varies with carbon sources used in fungal cultivation. Further research is necessary to identify the risk factors associated with selected species and carbon sources for mycoprotein production.
Cell-cultured meat and meat products are witnessing great interest from several startups, established animal meat players as well as investors. However, there is a lack of risk assessment and research on the safety of cultured meat, with the current focus being on improving the technology/ process for cultured meat production. The main considerations for the safety assessment of cultured meat include the source of cells, characterisation, production process and nutritional information.
Replicating the characteristics of fresh, unprocessed meat would require several complex technical interventions including simulating the role of blood in delivering oxygen and nutrients throughout the thicker pieces of tissue, as well as co-culturing fat, muscle, and connective tissues. Some cell-cultured meat products being developed may not be identical to conventional animal meat. The final product may contain medium components and additives for cell proliferation and differentiation that can increase to higher concentrations on media recycling. It may also contain hormones and antibiotics, scaffolding materials, other novel ingredients, etc.
The cells may also be genetically modified to express new proteins, generate induced pluripotent stem cells (iPSC), increase cell culture density through an altered signalling pathway. If applied, genetically modified cells may form the core of the final product, hence safety assessments of the resulting products will be required. The continuous sub-culturing and passaging of cell lines may result in changes in cell morphology, function, and proliferation rate due to physiological adaptation or genetic drift, resulting in a final product that has characteristics different to those of conventional meat. The source animal and use of animal-origin ingredients may pose the risk of transmission of infectious diseases and prions. Depending on the cell source, production medium, method, etc., the toxicity and safety assessments may be required to demonstrate the safety of the final food product.
Proteins from insects
Insects are emerging as a viable food and feed option with the nutritional value of insects, the environmental benefits as well as improvements in livelihoods associated with insect farming driving the mass rearing of insects. However, edible insects can also be associated with several food safety hazards including biological agents, chemical contaminants, anti-nutritional factors, etc, depending on the insect species, feed substrate used, as well as on how the insects are reared, harvested, processed and consumed.
While the microbial risks associated with edible insects can be controlled by following good hygienic practices during rearing and processing operations, the chemical contamination or bioaccumulation of heavy metals can be challenging to control and hence can pose significant risks. Insects reared on agri residues may be exposed to mycotoxins, pesticides, toxic metals, among other contaminants
Insect-based foods may pose potential allergenic risks to consumers, particularly to those who are allergic to crustaceans due to allergen cross-reactivity. There is significant overlap in allergenic proteins found in insects and those found in shellfish like crabs and prawns.
A recent study has identified 20 proteins found in cricket food products that could cause serious allergic reactions in some people. With shellfish allergies affecting three per cent of the global population, this may become a significant issue and could mean that insect-based foods need to be tested and labelled correctly to ensure people with allergies do not consume them unknowingly. While evaluating the safety of yellow mealworm as a novel food pursuant to Regulation (EU) 2015/2283, the European Food Safety Authority (EFSA) Panel concluded that the consumption of mealworm may induce primary sensitisation and allergic reactions to yellow mealworm proteins and may cause allergic reactions in subjects with allergy to crustaceans and dust mites.
Safety evaluation and regulatory framework
The national food legislative frameworks can ensure the safety of alternative proteins and some regulatory agencies have started to develop guidance for safety assessments based on available scientific evidence. In December 2020, Singapore became the first country to approve a cultured chicken product using the novel food regulatory framework introduced by Singapore Food Agency (SFA) in 2019. SFA’s novel food regulatory framework requires companies to seek pre-market assessment for novel food such as alternative protein products that do not have a history of being consumed as food. In EU too, the EU Novel Foods Regulation [(EU) 2015/2283], which came into force in January 2018, lists products produced through cell or tissue cultures derived from animals and from new sources such as microorganisms, fungi, algae and animals or their parts (with exception of products that have historical human consumptions prior to May 15, 1997) as novel foods.
All novel food products are subject to a pre-market authorisation, including a safety assessment conducted by the EFSA. However, in case genetic engineering is used in the production of cultured meat, the (Regulation (EC) 1829/2003) Regulation on genetically modified food and feed might apply. In 2021, yellow mealworm (Tenebrio molitor) was deemed safe for human consumption by the EFSA Panel on Nutrition, Novel Foods and Food Allergens, in compliance with the Regulations (EC) 2015/2283. In the USA, the FDA and the USDA-FSIS have agreed upon a joint regulatory framework to regulate the cell cultured food products from livestock and poultry. FDA will oversee cell collection, cell banks, cell growth and cell differentiation, whereas USDA-FSIS will monitor post-harvest processes, including the production and labelling of the final food products derived from the cells of livestock and poultry.
In India, the FSSAI has still not determined the regulatory framework for alternate sources of proteins, except for standards of dairy analogues. The potential FSSAI regulatory pathways for alternative proteins may come under non-specified food framework, which includes novel foods or novel food ingredients or processed with the use of novel technology and articles of food and food ingredients consisting of or isolated from bacteria, yeast, fungi, or algae. Labelling of alternative proteins is critical for letting consumers know what they are eating, what is the source of an ingredient or food product, how it was processed, and potential safety risks like allergens. Several national regulators have already initiated measures in the consumer interest.
However, differences in national regulatory frameworks, safety assessments and labelling can be challenging for industry to offer their products in diverse markets. There is a need for harmonisation or agreement on safety assessment and evaluation procedures for alternative protein sources and consumer benefit measures such as labelling of alternative proteins.
Adoption depends on awareness
Alternative proteins are a growing segment, and there is a need for collaborative efforts by industry and other stakeholders in safety assessments of various alternative protein sources and to ensure the safety of food products with alternative proteins in commercial-scale production. With rising consumer awareness and demand for transparency, there is a need for greater communication of scientific research and scientific evidence with all the stakeholders for wider adoption of alternative protein sources.
Dr Satyanarayana KV, Food Processing Practice Lead, Sathguru Management Consultants, Hyderabad