Should people eat more bugs?

Black soldier fly larvae, whilst well-established as a popular feeder insect for our animals, could soon be making it to our own plates.

Black soldier fly larvae (Hermetia illucens)

The larvae of the black soldier fly (Hermetia illucens), sometimes referred to as ‘calci-worms’ contains more iron and zinc than lean meat and more calcium than meat. The much eco-friendlier way of farming yields many times the protein of cattle-grazing or even growing soybeans.

New research by Leah W. Bessa et al at the University of Queensland has analysed the potential for utilising these insects in human diets in the aftermath of the COVID-19 pandemic. With over 2 billion people already consuming insects as part of their diet, the cultural barriers preventing this new diet option in the West, whilst deep-rooted, may begin to crumble as we are exposed to the benefits of consuming insects.

Their research confirmed:

- 0.5 hectares of black soldier fly larvae farming can produce more protein than cattle grazing on around 1200 hectares of farmland or 52 hectares of soybeans.

- The macro and micronutrient compositions are excellent for human consumption.

- The chitin content, while difficult to digest for some species, acts as a valuable fibre in the human body.

- The nutritional composition of the larvae changes drastically over time, allowing them to be harvested at the ideal times to be utilised for specific purposes including food, processed protein, butter and fat alternatives.

- Up to 50%-70% of lipid contents can be effectively utilised to create butter substitutes.

- Insects can be used to make beef patties and sausages and were rated well by consumers against vegetarian patties.

- Black soldier fly larvae can play an important role in breaking down organic matter. This matter/substrate can be altered to change the nutritional composition of the larvae.

However, there are also certain barriers preventing the bug boom:

- Larvae would have to be reared on clean ‘waste’ to prevent harmful levels of heavy metal uptake and these would have to be monitored rigorously.

- Larvae are innately decomposers, meaning there is a risk of microbial colonies in the substrate which could potentially be harmful.

- Although insect chitin is a promising alternative to crustaceans, it can still cause allergic reactions in some individuals.

Crispy bamboo caterpillar

The promising research may be the start of new things to come. However, a new surge in consuming bugs in the West is highly unlikely. An analysis of cultural exposure helped identify patterns in insect consumption. For example, Thai consumers were repulsed at the thought of consuming mealworms. Equally, Kenyan consumers found termites to be familiar, but mealworms to be disgusting. However, Dutch consumers found mealworms to be the most culturally acceptable insect to eat. Chinese consumers preferred to eat their insects whole, but Westerners preferred them to be processed and disguised in other foods.

Bessa writes: “Although consuming BSFL, among other insect species, may be a controversial topic in the Western culture met with disgust and apprehension, cultural attitudes and preferences can change. In order to normalize BSFL, farmers and producers need to create and maintain a constant, inexpensive supply of BSFL-based products making them readily available for consumers to try at will. BSFL has the potential to become an accessible and inexpensive insect species; however, there needs to be a strong drive to shift their role from only an animal feed option to that of a viable human food source.” 

“Understanding the functional properties of BSFL will allow for optimization of processing parameters to ensure that products of good quality and sensory properties can be produced, which is the most important aspect determining consumer acceptance. Last, the farming of BSFL specifically for human consumption needs to be developed and optimized to create a low-priced, safe, and standardized supply of BSFL that will make the development and use of BSFL desirable in the food industry.”

Belalang Goreng (crispy fried grasshopper)

Source: Bessa LW, Pieterse E, Marais J, Hoffman LC. Why for feed and not for human consumption? The black soldier fly larvae. Compr Rev Food Sci Food Saf. 2020;19 2747-2763