Busisiwe Gunya¹, Patrick Julius Masika^{1, 2,}, Arno Hugo³, Voster Muchenje¹

Background: Eisenia foetida are used as a feed source. However, information on nutrient composition and fatty acid profiles of earthworm E.foetida is limited, making it complex to include them into feed formulation. Objective: The aim of this study was to determine the nutritive value of freeze-dried and oven-dried earthworms, E. foetida. Design: The earthworms were oven- or freeze-dried, then analysed for nutrient composition (protein, fat, moisture and minerals) according to AOAC method and fatty acids using gas chromatography. Results: Protein content was higher in freeze-dried earthworms while fat content of earthworms was not influenced by drying methods used. Most minerals (macro and micro) of E. foetida were significantly different except for calcium (P < 0.05) with freeze-dried E. foetida having the predominant minerals than oven-dried earthworms. Most of essential fatty acids were significantly higher in oven-dried E. foetida than in freeze-dried earthworms. No significant differences (P > 0.05) were observed on Margaric, Vaccenic, Arachidic, Tricosanoic, omega-3, SFA, MUFA, n-3, PUFA: SFA and PUFA/MUFA between oven-dried and freeze-dried samples. Conclusions: The study revealed that freeze-dried E. foetida can serve as a better source of nutrients than oven-dried earthworms whereas fatty acids were better in oven-dried E. foetida than freeze-dried E. foetida. These results indicated that the effects of drying methods on E. foetida nutritive value were different.

chemical composition, drying methods, Eisenia foetida, fatty acids