Comparative Assessment of Drying Methods on Selected Quality Properties of Edible Caterpillars (Lepidoptera litoralia)

Abstract

This study assessed the effects of five drying methods on selected quality properties of edible caterpillar (Lepidoptera litoralia) flour, with emphasis on proximate composition, functional properties, mineral content, and vitamin content. The methods evaluated were air drying (A: 8 days), sun drying (S: 6 days), oven drying (O: 65 °C, 5 h), microwave drying (M: 300 W, 12 min), and cabinet drying (C: 70 °C, 4 h). Most measured chemical and functional properties differed significantly among treatments (p < 0.05). Moisture content ranged from 4.97% (O) to 12.46% (A). Protein content was highest in the air-dried sample (35.46%) and lowest in the sun-dried sample (29.55%), while fat content ranged from 27.51% to 36.13%. Ash content was highest in the air-dried sample (4.97%) and lowest in the cabinet-dried sample (2.74%). Crude fibre content ranged from 3.86% to 6.82%, and carbohydrate content ranged from 4.16% to 26.94%. Water absorption capacity ranged from 198.95% to 276.64%, while oil absorption capacity ranged from 92.89% to 141.38%. Air drying produced the highest values for both properties. Sun drying yielded the highest dispersibility (74.66%) and solubility index (41.93%). Potassium was the predominant mineral, ranging from 245.69 to 413.62 mg/100 g. Air drying produced the highest sodium, potassium, magnesium, and zinc values, whereas the sun-dried sample had the highest mean iron value. Cabinet drying produced the highest vitamin A content (3.85 g/100 g), while air drying produced the highest vitamin E, vitamin B12, and vitamin C contents. Overall, controlled oven, cabinet, and microwave drying reduced moisture more effectively, whereas air drying retained higher levels of several nutrients and functional properties. The selection of a drying method should therefore balance moisture reduction, nutrient retention, and the intended food application.