Mohsen Ranjbaran

• PhD
• Senior Engineer - Process Development at Illumina

Nucleic-acid biosensors have emerged as useful tools for on-farm detection of foodborne pathogens on fresh produce. Such tools are specifically designed to be user-friendly so that a producer can operate them with minimal training and in a few simple steps. However, one challenge in the deployment of these biosensors is delivering precise sample vo...

Laboratory-based nucleic acid amplification tests (NAATs) are highly sensitive and specific, but they require the transportation of samples to centralized testing facilities and have long turnaround times. During the Coronavirus Disease 2019 (COVID-19) pandemic, substantial advancement has been achieved with the development of paper-based point-of-...

Foodborne outbreaks caused by fecal contamination of fresh produce represent a serious concern to public health and the economy. As the consumption of fresh produce increases, public health officials and organizations have pushed for improvements in food safety procedures and environmental assessments to reduce the risk of contamination. Visual ins...

Rapid nucleic-acid biosensors are useful for on-farm detection of foodborne pathogens on fresh produce during pre-season and pre-harvest stages. Such tools aim to be user-friendly so that a producer could operate them in a few simple steps and detect multiple targets. Currently, an easy-to-use device for on-farm applications does not exist commerci...

Paper-based biosensors are microfluidic analytical devices used for the detection of biochemical substances. The unique properties of paper-based biosensors, including low cost, portability, disposability, and ease of use, make them an excellent tool for point-of-care testing. Among all analyte detection methods, nucleic acid-based pathogen detecti...

Fecal contamination of fresh produce from human and animal sources is a public health concern due to the risk of foodborne illnesses. The current standard laboratory procedures for microbiological analyses usually require an enrichment step that involves several hours. Molecular techniques such as polymerase chain reaction (PCR) have been used to d...

Background: Understanding interactions between bacteria and fresh produce is of practical importance in the prevention and mitigation of foodborne and plant diseases. Microfluidic approaches, which usually operate at the same scale as produce–bacteria interactions, provide a platform for understanding interactions and detecting contamination. Scope...

The landscape of mathematical model‐based understanding of microbial food safety is wide and deep, covering interdisciplinary fields of food science, microbiology, physics, and engineering. With rapidly growing interest in such model‐based approaches that increasingly include more fundamental mechanisms of microbial processes, there is a need to bu...

While it has been understood that vacuum cooling can result in bacterial infiltration into plant leaves, the details of the contamination and infiltration pathways could be explored further. We investigated contamination/infiltration pathways via experimental and modeling work wherein 1) microorganisms (Escherichia coli strain K12) external to the...

Evaporation of sessile droplets on the surface of plant leaves is a process that frequently occurs during plant growth as well as postharvest processes. Evaporation-driven internal flows within sessile droplets can transport microorganisms near the leaf surface, facilitating their adhesion to surface microstructures such as trichomes, and infiltrat...

Light is one of the factors that can play a role in bacterial infiltration into leafy greens by keeping stomata open and providing photosynthetic products for microorganisms. We model chemotactic transport of bacteria within a leaf tissue in response to photosynthesis occurring within plant mesophyll. The model includes transport of carbon dioxide,...

Selective or enhanced heating of a solid in a solid–liquid mixture in microwaves that can lead to enhanced boiling and possibly bumping was studied. A soup containing broth and particulate foods was heated in a cylindrical container in a standard domestic microwave oven. Heating patterns were obtained using a coupled three dimensional thermal‐elect...

Evaporation-driven internal flows within a sessile droplet can transport microorganisms close to the leaf surface and facilitate their infiltration into the available openings, such as stomata. Here, using microfabricated surfaces out of polydimethylsiloxane, the sole effects of evaporation of sessile droplets in contamination of plant leaves was s...

Vacuum cooling of leafy greens can quickly lower their temperature, thus efficiently extending their shelf-life. However, passive bacterial infiltration into the leaf through openings such as stomata or wounds during this process presents a risk. This study develops a mechanistic model of stomatal infiltration and elaborates controlling parameters....

The kinetics of combined hot air-infrared thin layer drying of paddy was studied. The mechanical quality aspects of paddy kernels dried at different drying conditions were evaluated in terms of percentage of cracked kernels and also required failure force obtained from bending tests. The well-known Artificial Neural Network (ANN) modeling technique...

Computational Fluid Dynamics (CFD) was applied threedimensionally to simulate the drying behavior of paddy in a deep-bed dryer. The commercial CFD software Fluent 6.3.26 was used. The deep-bed paddy drying process and performance were studied by incorporating user-defined function (UDF) in Fluent written in C language. The predicted drying paramete...

A general mathematical model of heat and mass transfer was developed to simulate the microwave-assisted fluidized bed drying of bulk grain. The model was solved using the well-known Runge-Kutta-Gill method. The model is capable of predicting the moisture content of soybean as well as the drying air parameters (i.e., drying air temperature and moist...

The drying behavior of moist spherical particles in a microwave-assisted fluidized bed dryer was simulated. The two-fluid Eulerian model incorporating the kinetic theory of granular flow was applied to simulate the gas–solid flow. The simulations were carried out using the commercial computational fluid dynamics (CFD) package Fluent 6.3.26. The eff...

The drying characteristics of soybean during combined hot air-microwave drying were examined. The experiments were carried out for combination of five microwave power densities (0.89, 1.6, 3.2, 4.3, 5.3 W/g) and four levels of air temperatures (30, 40, 50 and 60 °C). Among several models which were fitted to the experimental data, the Modified Two...

In the present study the drying behavior of moist spherical particles in a pilot-scale microwave-assisted fluidized bed dryer was modeled. The Eulerian multiphase model was used to simulate the hydrodynamics of fluidized bed within the framework of the commercial CFD package, Fluent 6.3.26. To expand the ability of Fluent to simulate the drying pro...

To simulate the drying process of green fig during hot air drying, the finite element method was applied. The governing equation of the moisture transfer was discrete to a system of first order differential equations for all nodes which was solved by finite difference method. For the purpose of grid study, three different grid resolutions were used...