Different microorganisms create different biochemical changes, and an improvement in one functional property may be accompanied by a reduction in another.

For food manufacturers, fermentation should therefore be considered an ingredient-engineering technology, not simply a preservation process.

The relevant question is not:

Can edible insects be fermented?

It is:

Can a controlled fermentation create a better ingredient for a specific food application?

Key Takeaways

• Fermentation can modify flavour, protein structure, digestibility and techno-functional properties of insect ingredients.

• Lactic acid bacteria, yeasts and filamentous fungi can produce very different results.

• Acidification may support microbial control, but fermentation does not replace validated food-safety processing.

• Proteolysis may increase protein solubility and accessibility but can also reduce some structure-forming properties.

• Solid-state fermentation of cricket powder has demonstrated improvements in water absorption, foaming, protein solubility and emulsion stability under specific experimental conditions.

• Fermentation may help integrate insect ingredients into familiar foods such as bakery products, beverages and fermented foods.

• The microorganism and fermentation process should be selected according to the final food application.

1. Fermentation Is Not One Process

The word fermentation covers a wide range of biological processes.

Food fermentation may involve:

• lactic acid bacteria;

• yeasts;

• filamentous fungi;

• mixed cultures;

• microbial enzymes;

• endogenous enzymes present in the food matrix.

Each microorganism interacts differently with the substrate.

As a result, fermentation can influence:

• pH;

• protein structure;

• peptides and free amino acids;

• lipids;

• volatile compounds;

• texture;

• microbial ecology;

• water-binding behaviour;

• emulsification;

• foaming;

• sensory characteristics.

This means that a “fermented insect ingredient” cannot be defined by fermentation alone.

Its properties depend on the complete processing system:

insect species + ingredient format + microorganism + moisture + temperature + fermentation time + oxygen availability + post-processing

2. Why Ferment an Insect Ingredient?

Edible insects can provide protein, lipids, minerals and other nutrients, but they can also present formulation challenges.

Depending on species and processing history, these may include:

• characteristic insect aroma;

• earthy or roasted flavour notes;

• bitterness;

• relatively low protein solubility;

• high lipid content;

• oxidation risk;

• chitin-associated structural material;

• poor compatibility with some food systems.

Traditional fractionation approaches may address some of these issues through:

• defatting;

• protein extraction;

• precipitation;

• filtration;

• enzymatic hydrolysis.

Fermentation offers another possibility.

Instead of simply separating components, microorganisms can biologically transform the ingredient.

This creates opportunities to modify both composition and functionality.

3. Lactic Acid Bacteria

Lactic acid bacteria are among the most important microorganisms in food fermentation.

Species belonging to groups such as Lactiplantibacillus and Latilactobacillus convert fermentable substrates into organic acids and other metabolic products.

In cricket-based ingredients, lactic acid fermentation has been associated with changes in:

• pH;

• organic-acid profile;

• amino acids;

• volatile compounds;

• fatty-acid profile;

• microbial population;

• sensory characteristics.

Acidification itself is technologically important because protein behaviour is strongly pH-dependent.

A change in pH may therefore modify not only microbial conditions but also:

• protein charge;

• solubility;

• hydration;

• interaction with other ingredients.

Fermentation can consequently affect both food safety parameters and formulation behaviour.

4. Fermentation and Food Safety

Fermentation has been used for centuries to improve food preservation.

Acidification and competition from desirable microorganisms can make the environment less suitable for certain undesirable microbes.

However, this principle should not be oversimplified.

Edible insects may carry:

• vegetative microorganisms;

• bacterial spores;

• environmental contaminants;

• post-processing contamination.

A successful fermentation therefore requires control of:

• raw-material quality;

• starter culture;

• fermentation temperature;

• fermentation time;

• pH;

• water activity;

• hygienic processing;

• packaging;

• storage.

Fermentation is one food-safety hurdle, not a substitute for a validated safety process.

Thermal treatment, microbiological specifications and hygienic design may still be necessary depending on the product.

5. Proteolysis: Changing the Protein System

One of the most important biochemical effects of fermentation is proteolysis.

Microbial proteases can break large proteins into:

• smaller protein fragments;

• peptides;

• free amino acids.

This may influence:

• digestibility;

• protein solubility;

• flavour;

• emulsification;

• foaming;

• bioactive peptide formation.

Smaller protein structures may interact more readily with water and digestive enzymes.

This creates the possibility of improving certain nutritional and technological characteristics.

But proteolysis has an optimum.

Excessive protein breakdown can reduce the ability of proteins to create:

• gels;

• structural networks;

• stable interfacial films.

More hydrolysis is therefore not necessarily better.

6. Can Fermentation Improve Digestibility?

Digestibility depends on much more than protein percentage.

In insect ingredients, it can be influenced by:

• protein structure;

• heat treatment;

• aggregation;

• chitin-associated material;

• lipid–protein interactions;

• processing history.

Fermentation may partially modify these barriers.

Microbial enzymes can make proteins more accessible by reducing molecular size and changing the surrounding matrix.

Research reviewed for Acheta domesticus suggests that certain fermentation systems can increase matrix digestibility and alter amino-acid availability.

However, digestibility improvements should be demonstrated experimentally rather than assumed.

Relevant measurements may include:

• in vitro gastrointestinal digestion;

• peptide release;

• amino-acid availability;

• protein digestibility;

• protein-quality indices.

The statement “fermented means more digestible” is scientifically too broad without supporting data for the specific ingredient.

7. Fermentation and Chitin-Associated Structures

Chitin is a structural polysaccharide present in the insect exoskeleton.

From a food-formulation perspective, chitin can influence:

• texture;

• particle perception;

• protein analysis;

• digestibility;

• fractionation efficiency.

Some microorganisms may produce enzymes capable of modifying components associated with the insect structural matrix.

This creates an interesting possibility.

Instead of removing all non-protein material through mechanical or chemical processing, fermentation could potentially modify parts of the matrix biologically.

The effect will depend strongly on the microorganism and process conditions.

8. Flavour May Be the Most Important Commercial Opportunity

Consumer acceptance remains one of the major challenges for insect-based foods.

In many markets, rejection is linked not only to the nutritional concept but also to:

• visible insects;

• unfamiliar appearance;

• aroma;

• aftertaste;

• cultural perception.

Fermentation can modify volatile compounds and therefore change aroma and flavour.

Microorganisms may produce or transform:

• organic acids;

• alcohols;

• aldehydes;

• esters;

• ketones;

• other volatile compounds.

This can potentially reduce some undesirable notes while producing new fermented or savoury characteristics.

For product developers, this is particularly interesting because flavour modification can be achieved at ingredient level before the final product is formulated.

9. Better Flavour Does Not Necessarily Mean Neutral Flavour

Fermentation may improve flavour quality.

It does not necessarily make an ingredient flavourless.

Depending on the microorganism, a fermented insect ingredient may develop:

• acidic notes;

• yeast-like aromas;

• fermented savoury notes;

• mushroom-like characteristics;

• greater umami perception.

These characteristics could be highly desirable in:

• savoury snacks;

• sauces;

• meat analogues;

• bakery products;

• seasonings.

The same profile may be unsuitable for:

• neutral protein beverages;

• vanilla nutrition drinks;

• delicate desserts.

The sensory objective should therefore be defined before choosing the fermentation culture.

10. Solid-State Fermentation

One of the most interesting approaches for edible-insect ingredients is solid-state fermentation.

In solid-state fermentation, microorganisms grow on a moist solid substrate with limited free water.

This approach is widely used in traditional food biotechnology and can be particularly relevant for insect powders.

A 2025 study investigated commercial Acheta domesticus powder fermented with:

• Pleurotus ostreatus;

• Rhizopus oligosporus.

The fermentation changed both nutritional and techno-functional properties.

Importantly, the two microorganisms did not produce identical results.

This demonstrates a fundamental R&D principle:

The microorganism is part of the ingredient-design strategy.

11. What the 2025 Study Found

In the solid-state fermentation study, both fungal systems modified cricket powder functionality.

The researchers reported that fermentation contributed to improvements in properties including:

• water absorption;

• foaming behaviour.

Rhizopus oligosporus also improved:

• protein solubility;

• emulsion stability;

and reduced fat content under the conditions tested.

The study also reported protein metabolisation and the formation of smaller proteins and peptides.

These results are important because they show that fermentation can do more than preserve an insect ingredient.

It can change what the ingredient can do inside a food system.

12. Rhizopus oligosporus

Rhizopus oligosporus is well known for its role in tempeh fermentation.

Its enzyme systems are capable of modifying:

• proteins;

• carbohydrates;

• lipids.

Applying this type of fermentation to insect ingredients creates an interesting bridge between traditional fermentation biotechnology and alternative-protein development.

In cricket powder, the reported improvements in protein solubility and emulsion stability suggest potential applications beyond simple nutritional enrichment.

A fermented cricket ingredient could potentially contribute technologically to the formulation itself.

13. Pleurotus ostreatus

Pleurotus ostreatus, commonly known as oyster mushroom, represents a different fermentation strategy.

Filamentous fungi such as Pleurotus species produce complex extracellular enzyme systems.

In the same cricket-powder study, P. ostreatus fermentation contributed to changes in nutritional and techno-functional behaviour, including water absorption and foaming.

This highlights an important opportunity.

Future insect fermentation systems do not need to rely exclusively on lactic acid bacteria.

The potential microbial toolbox includes:

bacteria + yeasts + fungi + mixed cultures

Each may produce a different ingredient.

14. Protein Solubility

Protein solubility is one of the most important parameters for many food applications.

Low solubility can contribute to:

• sedimentation;

• poor dispersion;

• aggregation;

• inconsistent texture.

Solubility depends on:

• pH;

• ionic strength;

• temperature;

• protein structure;

• processing history.

Fermentation can modify protein size and structure and may therefore alter solubility.

The improvement observed with R. oligosporus demonstrates that biological processing can be used as a functionalisation tool.

But the result should always be tested at the pH and conditions of the final product.

15. Water-Holding Capacity

Water-holding capacity influences:

• hydration;

• texture;

• viscosity;

• product yield;

• moisture retention.

Increased water absorption can be beneficial in:

• bakery;

• nutrition bars;

• fillings;

• structured foods;

• meat analogues.

However, very high hydration may create problems in some applications.

In beverages, for example, excessive water binding may increase viscosity or contribute to instability.

Functionality is therefore always application-specific.

16. Foaming

Foaming requires proteins or other surface-active molecules to move to the air–water interface and create a stabilising layer.

Fermentation can modify:

• protein molecular size;

• surface characteristics;

• flexibility.

The solid-state fermented cricket study reported improvements in foaming-related properties.

This could potentially be relevant to:

• aerated bakery products;

• whipped foods;

• some beverages;

• structured snacks.

Foam capacity and foam stability should nevertheless be evaluated separately.

A system that produces a large amount of foam may not necessarily maintain it.

17. Emulsification

Many foods contain oil and water simultaneously.

Examples include:

• sauces;

• dressings;

• spreads;

• nutrition drinks;

• meat analogues.

Proteins can help stabilise these systems by positioning themselves at the oil–water interface.

Fermentation-induced changes in protein structure can affect this behaviour.

The reported improvement in emulsion stability following R. oligosporus fermentation is therefore technologically important.

It suggests a transition from:

insect ingredient as nutrition

to

insect ingredient as functional food component.

18. Fermentation and Bioactive Peptides

Proteolysis during fermentation can also generate smaller peptides.

Some insect-derived peptides have demonstrated biological activity in laboratory studies, including potential:

• antioxidant;

• antimicrobial;

• antihypertensive;

• anti-inflammatory

effects.

This is a promising research area.

However, laboratory activity should not automatically be translated into a consumer health claim.

Commercial substantiation may require evidence on:

• peptide identity;

• effective concentration;

• stability;

• digestion;

• bioavailability;

• human efficacy;

• regulatory compliance.

Bioactive peptides should therefore be treated as a research opportunity, not an automatic marketing claim.

19. Fermentation Can Also Create Problems

Fermentation is not inherently beneficial.

Poorly controlled processes can produce:

• undesirable microorganisms;

• off-flavours;

• excessive acidification;

• inconsistent protein breakdown;

• texture defects;

• spoilage;

• unwanted metabolites.

The fermentation culture must therefore be:

• food appropriate;

• reproducible;

• well characterised;

• compatible with the target process.

Critical variables should be defined, including:

• inoculum;

• time;

• temperature;

• moisture;

• oxygen;

• pH;

• post-fermentation treatment.

20. Allergenicity Does Not Disappear Automatically

Edible insects can present allergenic risk, including potential cross-reactivity with crustacean and dust-mite allergens.

Fermentation changes proteins.

It should not be assumed to eliminate allergenicity.

Any commercial fermented insect ingredient still requires appropriate:

• allergen assessment;

• labelling;

• regulatory review.

Functional improvement and food safety need to be developed together.

21. Familiar Food Formats May Improve Acceptance

Fermentation has another strategic advantage.

Many fermented food formats are already familiar to consumers.

Examples include:

• bread;

• yogurt;

• fermented drinks;

• sauces;

• savoury products.

Research reviewed for cricket ingredients has examined applications in bread, biscuits, yogurt and beverages.

This matters because product acceptance is influenced by more than the ingredient.

Consumers respond to:

• familiarity;

• visibility;

• taste;

• texture;

• product format.

Integrating insect-derived ingredients into familiar foods may therefore be more effective than emphasising the insect itself.

22. Bakery Applications

Bakery products may be particularly suitable for fermented insect ingredients because they can accommodate:

• darker colour;

• roasted aromas;

• particulate ingredients;

• flavour complexity.

Potential development objectives include:

• protein enrichment;

• improved water absorption;

• flavour development;

• nutritional enhancement.

But formulation still requires evaluation of:

• dough rheology;

• loaf volume;

• crumb texture;

• browning;

• aroma;

• aftertaste;

• shelf life.

Fermentation does not remove the need for product-level validation.

23. Fermented Beverages

Beverages are considerably more demanding.

A fermented insect beverage may require control of:

• protein solubility;

• sedimentation;

• pH;

• viscosity;

• flavour;

• colour;

• microbial stability.

Fermentation may contribute distinctive flavour and nutritional positioning.

But it can also increase formulation complexity.

In liquid systems, functional testing should therefore occur under actual product conditions.

24. Yogurt-Type and Fermented Products

Yogurt and similar fermented matrices may provide an interesting application environment.

These products already have:

• expected acidity;

• fermentation-derived aroma;

• opaque appearance;

• structured texture.

Insect protein could potentially contribute to:

• protein enrichment;

• viscosity;

• nutritional positioning.

Potential technical problems include:

• graininess;

• phase separation;

• syneresis;

• excessive viscosity;

• flavour imbalance.

The interaction between insect proteins and the existing food matrix must therefore be studied.

25. When Should Fermentation Occur?

Fermentation can potentially be introduced at different stages.

Route A

Whole insect → fermentation → drying → milling

Route B

Insect powder → fermentation → drying

Route C

Defatted powder → fermentation → fractionation

Route D

Protein-rich fraction → controlled fermentation

Each route creates a different ingredient.

Fermenting the entire insect matrix may modify protein, lipid and structural components simultaneously.

Fermenting an isolated protein allows more targeted modification.

The correct route depends on the development objective.

26. Fermentation Versus Enzymatic Hydrolysis

Fermentation and enzymatic hydrolysis are related technologies but should not be treated as identical.

Enzymatic hydrolysis

Uses selected enzymes under controlled conditions.

It may provide:

• more precise protein breakdown;

• controllable enzyme dosage;

• targeted hydrolysis.

Fermentation

Uses living microorganisms.

It can combine:

• proteolysis;

• acidification;

• flavour development;

• metabolite production;

• matrix modification.

Fermentation is biologically more complex.

The two approaches may also be combined in future ingredient-development systems.

27. What Should R&D Teams Measure?

A serious fermentation project should go beyond protein percentage.

Composition

• protein;

• lipid;

• moisture;

• ash;

• pH.

Microbiology

• starter performance;

• total counts;

• pathogens;

• spoilage organisms.

Protein Functionality

• solubility;

• water-holding capacity;

• oil-holding capacity;

• foaming;

• emulsion stability;

• gelation where relevant.

Nutrition

• digestibility;

• amino-acid profile;

• peptide distribution.

Sensory

• aroma;

• flavour;

• bitterness;

• acidity;

• colour;

• texture;

• aftertaste.

Shelf Life

• oxidation;

• moisture stability;

• microbiology;

• sensory deterioration.

Only then can fermentation be evaluated as an ingredient-engineering process.

28. A Practical R&D Framework

Before fermenting an insect ingredient, define six points.

1. What problem are we solving?

Flavour?

Solubility?

Digestibility?

Water binding?

Microbial stability?

2. What material are we fermenting?

Whole insect?

Powder?

Defatted powder?

Protein fraction?

3. Which microorganism is appropriate?

Lactic acid bacteria?

Yeast?

Filamentous fungus?

Mixed culture?

4. What food will contain the ingredient?

Bread?

Drink?

Bar?

Sauce?

Meat analogue?

5. What is the technical endpoint?

Target pH?

Flavour?

Solubility?

Water holding?

Emulsification?

6. How will the fermentation be stopped and stabilised?

Drying?

Pasteurisation?

Cooling?

Freeze drying?

Direct incorporation?

This final step is essential for industrial reproducibility.

Conclusion

Fermentation represents one of the most promising biological tools for the next generation of edible-insect ingredients.

It can potentially modify:

• flavour;

• digestibility;

• protein solubility;

• water absorption;

• foaming;

• emulsification;

• microbial ecology.

But fermentation is not automatically beneficial.

Different microorganisms create different ingredients.

An improvement in one property may be accompanied by a reduction in another.

The correct question is therefore not:

Does fermentation improve insect protein?

It is:

Which fermentation process creates the functionality required by the target food system?

This distinction moves edible insects away from novelty and toward professional food ingredient technology.

The future role of fermentation may be to transform biologically complex insect materials into more controlled, functional and application-specific ingredients.

Selected Scientific References

1. Haghayeghi, S.M.H., Osimani, A., Aquilanti, L.
Fermentation of House Crickets (Acheta domesticus): Boosting Quality and Functionality in Cricket-Based Food Ingredients.
Foods. 2025;14(23):4003.
DOI: 10.3390/foods14234003

2. Cricket powder (Acheta domesticus) nutritional and techno-functional properties and effects of solid-state fermentation with Pleurotus ostreatus and Rhizopus oligosporus.
Innovative Food Science & Emerging Technologies. 2025;104:104066.
DOI: 10.1016/j.ifset.2025.104066

3. Mittal, R.K., Krishna, G., Sharma, V.
Biotechnological Advances in Enzymatic Hydrolysis and Fermentation for Edible Insects: Functionality, Acceptability and Safety.
Current Pharmaceutical Biotechnology. 2025;26(9):1287–1302.
DOI: 10.2174/0113892010304236240517060354