The University of Pavia (Ruggeri et al., 2023) has just published on Antioxidants a study where the digestibility of proteins, the antioxidant action and the taste of an atomized powder of crickets bred and processed in Italy are analysed. (1)
1) Atomized cricket powder
Cricket powder object of study – rather than deriving from a traditional process of wet grinding and drying in the oven (or microwave) – was created by spray-drying (atomization). The same technology used to produce powdered milk. The solution is sprayed into a drying tower which instantly transforms it into a very fine powder.
'cricket flour' it is in any case a wording that the European Commission has censored, for reasons of mere appearance. Indeed, DG Sante affirmed that the products of the grinding of foods of animal origin, including insects, must be defined 'dust'(powder), while the term 'flour'(flour) would be used to designate foods of plant origin. (2) Neglecting the existence of fish meal, among the others.
2) Protein digestibility
The digestibility of proteins of atomized cricket powder – measured in vitro, through the PDCAAS (Protein Digestibility Corrected Amino Acid Score) – reached the maximum score (1, out of a range from 0 to 1). Equal to eggs, milk and their proteins, and eggs.
FAO recommends using a different method, the DIAAS (Digest indispensable amino acid score), to better estimate the availability of all the amino acids present in proteins following intestinal absorption. Indeed, the PDCAAS would present some limitations, such as the lack of consideration of the absorption at the level of the ileum (final intestine). (3)
EFSA vice versa recommends the PDCAAS, until sufficient data are available on the digestibility of amino acids in the ileal tract. This is because PDCAAS offers a high availability of faecal protein digestibility data. (4)
The chitin it is a structural polysaccharide – part of the exoskeleton of insects, such as crustaceans and the cell wall of fungi – which becomes part of the overall composition of the powder. It is a prebiotic fiber and can exert positive effects, such as stimulating the intestinal microbiota and contributing to digestion.
its consumption, like that of each fiber, must not be excessive (25-35 g/the). And its intake must be limited by children up to 3 years of age (max 19 g/the), since fibers can compromise the absorption of some essential nutrients for growth and development (e.g. proteins, minerals). (5)
Technology spray-drying however, it also allows to significantly reduce the particle size of chitin, which the atomized powder of crickets contains in an average quantity (3,28%) much lower than the most consumed edible mushrooms (e.g. champignon, pleutorus, shiitake). (6)
4) Antioxidant action
The antioxidant action of atomized cricket powder was tested with DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. The ability to reduce free radicals was thus evaluated, which proved to be effective for a period of time up to 24 hours. This action is probably to be attributed to the bioactive molecules (e.g. vitamins B2, B12 and E) and the proteins present in the powder.
5) Particle size, taste
The particles of atomized cricket powder – measured with an electron microscope (scanning electron microscope, SEM) – have an average size less than half that of traditional cricket flours (diameter 22 μm v. 50-100 μm).
The taste of the atomized powder is consequently more neutral, thanks to the fineness obtained with it spray-drying. The result is greater palatability and sensory acceptance by consumers, compared to traditional cricket flours whose flavor recalls that of toasted hazelnuts.
6) Cytotoxicity tests
The cytotoxicity tests of the atomized powder of crickets were performed by interaction of its suspensions and extracts with tumor cells of the Caco-2 line (colon carcinoma). None of the extracts and suspensions caused cell toxicity, except for the suspensions at the highest concentration. In this case the toxicity was attributed to the concentration per se of the particles, and to the reduced availability of nutrients and gases.
7) Public contributions and funding
A systematic review it was made using atomized cricket powder produced by an innovative agricultural startup based in Milan, Alia Insect Farm. Its founder Carlotta Totaro Fila, a graduate in food science and technology with extensive experience in the food industry infant foodin turn participated in the research.
The project 'ON Foods' (Research and innovation network on food and nutrition Sustainability, Safety and Security—Working ON Foods), where this study takes place, is financed by the Ministry of University and Research (MUR) through the National Recovery and Resilience Plan (PNRR), which is in turn financed by the European fund NextGeneration EU. (7)
8) Provisional conclusions
The product object of study will soon be submitted to an application for authorisation novel food, with the support of our team of WIISE extension, division DO (Food and Agriculture Requirements). In compliance with food safety requirements, no nutritional disadvantages, labeling. (8)
Spray-dried cricket powder it proves to be an 'innovation within innovation', thanks to its strong functional and sensory properties which lead to a greater versatility of this ingredient compared to traditional cricket flour. Sustainable proteins of high biological value, produced in an Italian agricultural micro-enterprise and even healthier than others. (9)
Dario Dongo and Andrea Adelmo Della Penna
Footnotes to the story
(1) Marco Ruggeri, Eleonora Bianchi, Barbara Vigani, Rita Sánchez-Espejo, Mattia Spano, Carlotta Totaro Fila, Luisa Mannina, César Viseras, Silvia Rossi, Giuseppina Sandri (2023). Nutritional and Functional Properties of Novel Italian Spray-Dried Cricket Powder. Antioxidants 12: 112, https://doi.org/10.3390/antiox12010112
(2) European Commission, DG SANTE. Letter 16.5.22 addressed to EFSA to change the name of the novel food authorization application of a cricket powder (NF 2020/1860). Ares(2022)3691415)
(3) FAO (2013). Dietary protein quality evaluation in human nutrition. FAO Food and Nutrition Paper, ISBN 978-92-5-107417-6, https://www.fao.org/ag/humannutrition/35978-02317b979a686a57aa4593304ffc17f06.pdf
(4) EFSA (2017). Scientific Panel on Dietetic Products, Nutrition and Allergies Draft Minutes of the 78th Plenary meeting. https://www.efsa.europa.eu/sites/default/files/event/170404-0m.pdf 4-6 April 2017, Parma (Italy)
(5) Renee Korczak, Alison Kamil, Lisa Fleige, Sharon M. Donovan, Joanne L. Slavin (2017). Dietary fiber and digestive health in children. N 75 (4): 241-259, https://doi.org/10.1093/nutrit/nuw068
(6) Janos Vetter (2007). Chitin content of cultivated mushrooms Agaricus bisporus, Pleurotus ostreatus and Lentinula edodes. Food Chemistry 102 (1): 6-9, https://doi.org/10.1016/j.foodchem.2006.01.037
(7) PNRR, MUR: 14 partnerships for research activities selected. https://www.mur.gov.it/it/news/mercoledi-03082022/pnrr-mur-selezionati-i-14-partenariati-attivita-di-ricerca Press release. 3.8.22
(8) Dario Dongo. Domestic crickets and novel foods, a bit of clarity. GIFT (Great Italian Food Trade). 17.1.23
(9) Andrea Adelmo Della Penna. Replacing red meat with house crickets? The NovRBA project. GIFT (Great Italian Food Trade). 25.5.22