Exploration of Antimicrobial Compounds from Edible Insects and Indigenous Chickens’ Skin and Feathers for Applications in Food and Industry
About the project
UK-registered Partner: University of Hertfordshire – Guogang Ren
Africa-registered Partner: Egerton University – Benard Oloo
Deteriorating food safety in Africa is a major cause of insecurity. We proposed a novel solution to extract antimicrobial compounds from parts of chickens and insects normally discarded during processing and to characterise them as possible food additives to delay spoilage and inhibit pathogenic organisms.
We also included an initial demonstration of inexpensive and sustainable food preservatives for the food industry. Chicken parts (feet, feather, skin, beak) and insects (cricket, locust, nsense) were investigated for their potential antimicrobial properties against representative pathogens E. coli, S. aureus and C. albicans. Extracts were prepared using alkaline hydrolysis or methanol extraction. Antimicrobial inhibition was observed from these extracts.
Our results illustrate the potential of chicken waste products and insect extracts as inexpensive and sustainable food preservatives that warrant further investigation. Poultry egg white and yolk were tested directly for antimicrobial properties, shells were cleaned, and ground followed by water or methanol extraction. Only egg whites showed significant antimicrobial properties.
Different rearing conditions and breed of bird influenced antimicrobial activity. Free range eggs showed the highest antimicrobial activity towards bacterial species, whilst duck eggs showed the highest antimicrobial activity towards yeast. Egg white was tested on sausages (with sodium metabisulphite preservative). At 4 °C, the egg whites enhanced the inhibition of microbial growth and at 16 °C, free range egg white reduced the growth of microbes by more than 50%.
Use of egg white extracts as food preservatives shows potential and the differing specificities of egg white from different species is intriguing.
Learn more about the project in this recording from our recent GCRF AgriFood Africa Project Showcase event.