The study – published inFood Control– evaluated the potential of edible insects as alternative protein source, examining the microbiological composition of fresh, processed and stored insects.
The researchers, from Wageningen University in The Netherlands and the Food and Agriculture Organization of United Nations (FAO), revealed that spore forming bacteria are a potential spoilage and safety risk for insect protein – even in cooked insects. However the team, led by Harmke Klunder of Wageningen, found that simple preservation methods – such as the use of lactic fermented cereals – are promising for protection against spoilage and the extension of shelf-life.
“Similar to other animal derived products, insects are rich in nutrients, moisture and contain their gut microflora providing a medium for growth of unwanted micro-organisms in certain conditions,”noted Klunder and her team.
“This makes insects susceptible for microbiological hazards if proper heat treatment or storage conditions are not applied,”they warned.“Edible insects need to be processed and stored with care.”
Protein potential
Klunder and her colleagues noted that growing pressure on the worlds’ livestock production sector in combination with continued undernourishment for many people in the world, have persuaded many to search for alternative protein sources.
One such solution would be to tap in to the ever growing market for insects, which are comparable to conventional livestock meat in terms of nutritional content.
“Edible insects are a well-appreciated food consumed in various regions in Asia, Africa and America,”they noted, adding that it has been estimated that nearly 1800 insect species are used for human consumption globally.
Indeed, last year were reported that a paper published by the UK Food Standards Agency found the use of purified or partially purified insect protein in processed foods could become a commercially viable possibility if a reliable source could be identified.
Sustainable nutrition?
While insects have not traditionally been used for food in the European Union, it is estimated by the FAO that around 2.5 billion people across the world have diets that routinely include insects. And the FAO is interested in promoting edible insects as a highly sustainable source of nutrition.
Despite the relatively widespread consumption of insects as food, information concerning their cross-border trade, economic importance, or food safety aspects of their processed products remains limited, said the researchers.
“In principle there are three ways insects could be consumed. First as whole insects, recognizable as such; second, whole insects processed in some powder or paste; third, as an extract such as a protein isolate,”explained the researchers.
“Due to increasing commercialization of insect farming and trade ... an exploratory evaluation of microbial content of fresh, processed and stored insects seemed timely,”they added.
Insect protein
In the new research, Klunder and her team analysed the use of insects for protein enrichment of food products and the microbiological content of whole edible insects as fresh, processed and stored insects.
The team found that a heating step is sufficient for inactivation ofEnterobacteriaceae,“however a remaining potential risk with edible insects is the presence of spore-forming bacteria.”
“Alternative preservation techniques without the use of a refrigerator were explored of which drying and acidifying seemed practical and promising,”said Klunder and her co-workers.
They added that the use of insect protein for the enrichment of fermented food products is possible, and provides mutual benefits –“as the decreased pH in lactic acid fermented products prevents the growth of potentially harmful microorganisms.”
Source: Food Control
Published online ahead of print, doi: 10.1016/j.foodcont.2012.02.013
“Microbiological aspects of processing and storage of edible insects”
Authors: H.C. Klunder, J. Wolkers-Rooijackers, J.M. Korpela, M.J.R. Nout