Abstract
The mulberry silkworm (Bombyx mori L.) is a common edible insect in many countries. However, the impact of thermal processing, especially regarding Thai silkworm powder, is poorly known. We, therefore, determined the optimum time for treatment in hot water and subsequent drying temperatures in the production of silkworm powder. The silkworms exposed to 90 °C water for 0, 5, 10, 15, and 20 min showed values of Total Phenolic Compounds (TPCs), 2,2-Diphenyl-1-picrylhydrazyl free radical scavenging (DPPH) assay, 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assay, and Ferric Reducing Antioxidant Power (FRAP) assay that were significantly (p < 0.05) higher at the 5 min exposure time compared with the other times. The reduction of microorganisms based on log CFU/g counts was ≥3 log CFU/g (99%) at the 5 min treatment. To determine the optimum drying temperature, the silkworms exposed to 90 °C water for 5 min were subjected to a hot-air dryer at 80, 100, 120, and 140 °C. The TPC value was the highest (p < 0.05) at 80 °C. The silkworm powder possessed significantly (p < 0.05) higher DPPH, ABTS radical scavenging ability, and ferric ion reducing capability (FRAP assay) at 80 °C compared with other drying temperatures. This study indicates that shorter exposure times to hot water and a low drying temperature preserve the antioxidant activities. High antioxidant activities (in addition to its known protein and fat content) suggest that silkworms and silkworm powder can make a valuable contribution to human health.
Highlights
The custom of consuming insects as a food source has been widely practiced by many people from all around the world for thousands of years [1]
Fresh after-silking silkworms (FASSs) showed a high lightness with an L* value of 58.11 ± 0.63 and b* value of 24.45 ± 0.98, indicating that FASS in this study was yellowish
According to Taba and Gogoi [28], fifth instar silkworm exists in three forms, i.e., bluish-white, yellow, and bluish-green
Summary
The custom of consuming insects as a food source (entomophagy) has been widely practiced by many people from all around the world for thousands of years [1]. Global population growth has led to the increase of food consumption, especially protein. Due to the high protein content, short life cycle, and rapid growth cycle, edible insects may serve as an alternative source of protein for humans, as suggested by Meyer-Rochow [2]. Food security is seen as one of the major global concerns, and the benefits of edible insect have been re-evaluated, as insects are rich in protein, fats, minerals, and essential vitamins, and contain low amount of carbohydrates. Insects are abundant and bred in large quantities [3].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
