Comparative Impacts of Vacuum and Hot-Air Drying on Physico-Chemical Properties, Sensory Quality, and Antioxidant Capacity of Shiitake and White Oyster Mushroom Jerky

Wong, Pey Hau (2026) Comparative Impacts of Vacuum and Hot-Air Drying on Physico-Chemical Properties, Sensory Quality, and Antioxidant Capacity of Shiitake and White Oyster Mushroom Jerky. Final Year Project (Bachelor), Tunku Abdul Rahman University of Management and Technology.

Text Wong Pey Hau_Full Text.pdf Restricted to Registered users only Download (1MB)

Abstract

The growing demand for sustainable, plant-based snacks has positioned mushrooms as promising candidates for texturised jerky. Beyond sustainability, mushrooms offer complete essential amino acids and a native microfibrillar network that replicates meat-like texture without ultra-processing. However, the high moisture content and perishability necessitate effective preservation strategies. This study investigates the impact of hot-air drying (HAD) and vacuum drying (VD) on the physico-chemical properties, antioxidant retention, and sensory acceptability of mushroom-based jerky derived from shiitake (SM) and white oyster (WOM) mushrooms. Antioxidant assays revealed significantly higher (p < 0.05) activities in VD samples: DPPH inhibition reached 72.25 ± 0.04% in VD WOM compared to 55.90 ± 0.06% in HAD WOM; FRAP values peaked at 44.58 ± 0.04 μmol Fe²⁺/g in VD SM versus 23.08 ± 0.17 μmol Fe²⁺/g in HAD SM; ABTS inhibition exceeded 61% in both VD groups, significantly higher than HAD SM (39.79 ± 1.26%) and HAD WOM (43.71 ± 0.21%). Total phenolic content was highest in VD SM (1.44 ± 0.00 mg GAE/g), while total flavonoid content was highest in VD WOM (2.17 ± 0.04 mg QE/g). Texture analysis showed HAD SM had the greatest hardness (2024.25 ± 121.04 g), gumminess (2024.28 ± 121.06), and chewiness (1979.42 ± 83.40), whereas VD WOM was softest (841.68 ± 34.93 g). Colour L* values indicated HAD WOM was significantly darker (7.00 ± 0.66) than VD SM (17.03 ± 4.23). Proximate analysis revealed VD SM retained higher protein (9.32 ± 0.10%), but lower fat (9.96 ± 0.50%) compared to HAD SM (17.20 ± 0.45%). Sensory evaluation (n=55) showed no significant differences in overall attributes (p > 0.05). To fulfill the objective of structural and organoleptic optimisation, VD is determined to be the superior processing methodology. VD successfully optimises structural formation by preserving cellular elasticity and preventing case-hardening defects, while fully maintaining baseline consumer sensory parity with conventional convective drying. Future work should incorporate accelerated storage studies and expanded microbial profiling to balance antioxidant retention, textural quality, and microbial safety for commercial scalability.