Influence of extraction techniques on the quality characteristics of silkworm pupal oil: A comparison of Soxhlet and maceration method

Silkworm pupae, a valuable by-product of sericulture, represent a rich source of proteins, essential fatty acids, cholesterol, chitin and vitamins, with potential nutritional, cosmetic and pharmaceutical applications. The present study ascertained oil extraction from silkworm pupae using two methods: Soxhlet and maceration. The quality characteristics analyzed included physicochemical properties and compositional characteristics (pH, color, moisture, viscosity, carotenoids, cholesterol, unsaponifiable matter and tyrosinase inhibition activity) and oxidative stability indices (free fatty acid, acid value, peroxide value, p-aniside value, TOTOX value and iodine value). Results indicated that the quality characteristics have been significantly affected by different extraction methods. The comparative analysis revealed distinct variations between the two extraction techniques: Soxhlet showed pH (6.17), color (14Y + 1.5R), moisture (0.1%), viscosity (35.00 cP),carotenoids (10µg/g), cholesterol (154.96µg/mL), unsaponifiable matter (1.81%), and tyrosinase inhibition activity (IC₅₀ = 25.04mg/mL) and maceration showed pH (6.0), color (14Y + 1.2 R) moisture(0.2%), viscosity (31.00 cP), carotenoids (12µg/g), cholesterol (160.825µg/mL), unsaponifiable matter and tyrosinase inhibition activity (IC₅₀ = 6.60mg/mL).The Soxhlet method showed free fatty acid (1.40%), acid value (2.8 mg KOH/g), peroxide value (2.44 meq/g), P-aniside value (5. 267), TOTOX (9.8) and iodine value (120 gI2/100 g), while as the maceration method had showed free fatty acid (0.95%), acid value (1.9 mg KOH/g), peroxide value (2.00 meq/g), P-aniside value (5. 267), TOTOX (9.2) and iodine value (119 gI2/100 g). These results affirm the influence of the extraction methods on the quality indices of the silkworm pupal oil.