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This study investigated the effects of microwave-assisted freezing on the quality attributes of button mushrooms (Agaricus bisporus). Four levels of microwave power (0, 10, 20, 30%) were applied to the mushroom samples during freezing. The quality attributes of the frozen and thawed mushrooms were then evaluated. The results suggested that higher microwave power produced the smaller and more uniform ice crystals. Moreover, the browning index of the mushroom samples increased with increasing microwave power. The textural properties (hardness) of the mushrooms were also affected by the microwave power, showing higher values as the power increased. Furthermore, the ratio of the microwave operating system's power to the freezer power was low and approximately 20% at the highest power level. Therefore, these findings confirm the potential of microwave-assisted freezing for reducing freeze damage to mushroom tissue and, thus, provide frozen mushroom with a better texture. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the impact of the flow behavior index (n) on heat transfer and fluid flow in carboxymethyl cellulose (CMC) solutions during the thermal process within a cylindrical container. The study employed a numerical model based on the finite element method to solve the governing equations for mass, momentum, and energy conservation. Four different values of n were considered, ranging from 0.25 to 1, representing varying degrees of non‐Newtonian behavior. The results revealed that this index significantly influenced the apparent viscosity of the fluid, subsequently affecting the fluid flow patterns and heat transfer. Specifically, the n = 0.25 fluid exhibited a notably higher Grashof number (GR) and velocity compared to the n = 1 fluid. The average GR for the n = 0.25 fluid was ~2300 times larger than that of the n = 1 fluid, while the average velocity for the n = 0.25 fluid was ~37 times higher. In addition, the study identified the presence of secondary flow in the CMC solution with n = 0.25, which enhanced fluid mixing and heat transfer. Notably, the slowest heating zone for the n = 1 fluid remained fixed at the mid‐height of the can, whereas for the n = 0.25 fluid, it continuously shifted and contracted, ultimately settling at the 10% height from the bottom of the can. These findings underscore the critical importance of considering the non‐Newtonian characteristics of the fluid and convective flow during heat transfer processes in product applications. Practical applications: The study investigates the impact of flow behavior indices of the CMC solution on heat transfer and fluid dynamics within cylindrical containers. By examining parameters such as concentration, temperature, and heating duration, the researcher aims to optimize thermal processing for liquid food products containing thickening agents, such as sauces, soups, or dairy items. These findings significantly contribute to ensuring the safety, quality, and nutritional value of diverse liquid food products. Moreover, the study's insights may lead to energy savings and reduced environmental impact by minimizing heating time and temperature during thermal processing. In summary, this research bridges scientific understanding with practical applications, benefiting both consumers and the environment. [ABSTRACT FROM AUTHOR]

A model for simultaneous heat and mass transfer during the cooking process of frozen hamburger has been developed, using a modified form of Darcy's law to describe the capillary flow of moisture and Fourier's second law in cylindrical coordinates to describe the heat transfer. The effects of cooking time (0 to 12 min), cooking temperature (140 to 160 °C), and patty thickness (10 to 14 mm) during the hamburger cooking process on temperature profile, moisture content, and inactivation kinetics of Salmonella bacteria were investigated. The results showed that the predicted temperature and moisture values are in good agreement with the measured data. Due to the low convective heat transfer coefficient in the upper part of the sample at the beginning of the cooking process, non-uniformity in temperature was observed, which was resolved by flipping the hamburger and resulted in a reduction in cooking time. In addition, an increase in the heating temperature results in an increase in the rate of evaporation and moisture loss from the hamburger patty. The simulation results showed that at a cooking temperature of 140 °C and a patty thickness of 14 mm, all points of the hamburger will not achieve a 12D reduction of Salmonella and there is a possibility of salmonellosis under these conditions. [ABSTRACT FROM AUTHOR]

The aim of this research was to investigate the impact of the number of hamburger flips on cooking loss and the safety of hamburger patties during contact heating. To achieve this, a kinetic model describing the thermal inactivation of Salmonella serotypes during the cooking of hamburger patties was developed and coupled with heat and mass transfer equations (moisture and fat loss). The model also incorporated the effect of shrinkage during cooking. The results showed that while increasing the number of flips helps to distribute heat more evenly and decrease the temperature difference across the patty, which can increase safety, it can also lead to greater loss of moisture and fat during cooking. In addition, although shrinkage has a significant effect on cooking loss in the model, its inclusion did not improve the accuracy of the model in predicting experimental data. Practical Applications: The research highlights the importance of not only conveying the risks of consuming undercooked hamburgers, but also providing guidance on how to cook hamburgers thoroughly while retaining their juiciness and flavor. This information is crucial for hamburger producers to promote best practices for cooking hamburgers that meet both safety and taste criteria. The study also emphasizes the role of the effects of consecutive flipping and product shrinkage on cooking loss, as well as temperature changes during single‐sided contact heating of frozen hamburger patties. By understanding these factors, hamburger producers can develop cooking protocols that minimize cooking loss while ensuring product safety and taste. Overall, this research has practical applications for the hamburger industry, as it provides a scientific basis for optimizing cooking processes that can improve product safety, quality, and taste. [ABSTRACT FROM AUTHOR]