Effects of Porosity and Thermal Treatment on Hydration of Mushrooms

In this study, hydration of mushroom as a porous food material has been studied considering their biphasic character. It consists of a solid phase that consists of intertwined hyphae and having cell walls with a swellable polymeric matrix and a pore phase made up by the space in between the hyphae. We have investigated the hydration of mushrooms as a function of initial porosity and thermal treatment. Variation in porosity is induced by the natural variation in the growth of mushroom. Porosity is measured by the weight gain during vacuum infiltration of mushroom caps with the mushroom isotonic solution. The hydration of the heat-treated mushroom shows a linear increase with the porosity of mushroom. Storage of mushroom increases the porosity with the number of storage days, which has also been confirmed with X-ray tomography(XRT) measurements. Finally, we show that the hydration of thermal-treated mushroom has two independent contributions, from porosity and temperature of the heat treatment. Current theories deal only with the latter contribution to the hydration of foods and need to be extended for accounting porosity of the food.</p

Change in Water-Holding Capacity in Mushroom with Temperature Analyzed by Flory-Rehner Theory

The change in water-holding capacity of mushroom with the temperature was interpreted using the Flory-Rehner theory for swelling of polymeric networks, extended with the Debye-Hückel theory for electrolytic interactions. The validity of these theories has been verified with independent sorption measurements. The change in water-holding capacity with temperature could be quantified as changes in three model parameters: the Flory-Huggins interaction parameter between the biopolymers and the aqueous solvent phase, the cross-link density of the network, and the biopolymer volume fraction at the relaxed state. The elastic pressure is analyzed using the Flory-Rehner theory, which is traditionally used to describe the swelling of polymers. From the explicit knowledge of the elastic pressure, we can determine how model parameters, such as the cross-link density, depend on temperature. We argue that the dependencies of model parameters can be understood as a consequence of protein denaturation. Having knowledge on how all contributions to the swelling pressure depend on temperature, and composition, we can compute the water-holding capacity of mushroom for a wide range of temperatures and mechanical loads

More efficient mushroom canning through pinch and exergy analysis

Conventional production of canned mushrooms involves multiple processing steps as vacuum hydration, blanching, sterilization, etc. that are intensive in energy and water usage. We analyzed the current mushroom processing technique plus three alternative scenarios via pinch and exergy analysis. The product yield, utility use, exergy loss, and water use are used as sustainability indicators. Whilst re-arrangement of the production process could maximally save up to 28% of the heat input and up to 25% of the water usage, the most important improvement is obtained by re-using blanch water, which improves the overall yield of the preservation and canning process by 9%, also saving water and exergy use in the production