Abstract:
To preserve the quality of the yellow mealworm, different drying methods are being
explored by farmers and processors. However, the energy costs associated with these methods
are usually high for smallholder insect-rearing farmers. Thus, the core aim of this study was to
investigate different drying procedures and their impact on the chemical composition of yellow
mealworm larvae. Yellow mealworms (exposed to sun, oven and freeze drying) were later analyzed
for their chemical composition and body color. Crude protein (CP) content of freeze and oven-dried
mealworms were similar (p > 0.05), but higher (p < 0.05) than those of the sun-dried samples. The
b (yellowness) color of the sun-dried samples scored the lowest value (p < 0.05) in comparison
with both oven and freeze-dried samples. The majority of the essential amino acids were higher
(p < 0.05) in the sun-dried mealworms than both oven and freeze-dried samples. Similarly, the fat
content of sun-dried mealworms was higher (p < 0.05) than if they had been oven or freeze dried.
However, SFA (saturated fatty acids), PUFA (polyunsaturated fatty acids) and n-6 fatty acids were
similar (p > 0.05) for all drying methods. We, therefore, conclude that sun drying resulted in the
same nutritional composition as freeze and oven drying despite the noted color changes. Freeze and
oven-drying strategies can be used to formulate mealworm-based feed and food products without
noticeable nutritional changes. For the benefit of small-scale insect-rearing farmers, an appropriate
drying technology that is affordable and easy to use should be developed considering the needs and
experiences of these farmers.
