Modeling of vacuum drying of pressed mycelium (Pleurotus eryngii) and its microstructure and physicochemical properties

Abstract

Mycelium is the vegetative part of the fungus that grows and forms fruiting bodies, called mushrooms. The Pleurotus eryngii variety mycelium is highly nutritious but perishable due to its high moisture content, making its drying necessary for further application. Pressing as a novel pre-treatment was applied to fresh mycelium from 3 to 5 kN force for 20-50 s, and its effect on drying time was observed. The pressed mycelium was further vacuum dried at different temperatures (40-60 C) and pressure (60-260 mmHg) conditions. The drying data was fitted with 10 thin layer drying models, and Akaike information criteria was applied for selecting the best model. The physicochemical properties like browning index (BI), water activity (a w ), water absorption index (WAI), water solubility index, and flowability were calculated. The study found that pressing at 5 kN for 30 s reduced the moisture content from 89% to 52% wb and drying time by 48%-50%. The drying curves showed lower drying time at higher vacuum and temperature conditions. The drying modeling suggested the best fit for Page, Wang and Singh, Verma, and Midilli models (R 2 > .9867, RMSE < .0514, SSE < .0112). The Akaike information criterion showed that the Midilli model is in good agreement with drying data (Akaike increment = 0) at seven conditions. Mycelium dried at 60 C and 60 mmHg showed less a w (0.215 ± 0.004) and BI (28.946 ± 0.066), and maximum WAI (5.365 ± 0.046 g/g). Flowability of the dried mycelium is not affected (p < .05) by vacuum drying conditions. Practical ApplicationsPressing as a non-thermal pre-treatment for drying can be used to reduce the drying time thereby saving the energy. As a natural fortificant, vacuum-dried mycelium has potential in improving the nutritional status of the food products. Furthermore, the drying modeling will aid in the creation of optimum drying conditions for mycelium and the design of a commercial-scale continuous drying system.

Incorporation of Mycelium (Pleurotus eryngii) in Pea Protein Based Low Moisture Meat Analogue: Effect on Its Physicochemical, Rehydration and Structural Properties

“…The increase in MY decreased the free water for syneresis, resulting in a significant increase ( p < 0.05) in WHC of LMMA. This may be attributed to the porous structure of the mycelium [ 31 , 36 ]. The cell structure and porosity highly affected the WHC [ 34 ].…”

Rheological modeling of marjoram fortified rice dough: Empirical and machine learning approach

“…According to thumb rules, models with Δi ≤ 2 have substantial support, while models with 4 ≤ Δi ≤ 7 have relatively less support, and models with Δi > 10 have essentially no support due to their inability to explain some substantial variability of data (Mandliya et al, 2022;Panigrahi et al, 2021).…”