Sensors & their Application in Food Processing Industries

In a food processing plant, food has to be carefully monitored for its safety and quality during the entire production process.

- Dawn C.P. Ambrose, Central Institute of Agricultural Engineering, Regional Station, Coimbatore

As for the applications of monitoring technologies, they range across the food industry. These monitoring technologies comprises of process control (the moisture content of the food; viscosity and texture); pH and conductivity (acidity and salt content); sugar content (glucose and sucrose are the main sugars monitored); food freshness including the detection of microbes (Escherichia coli, Salmonella, etc.) and the detection of microbial toxins (liquid and gas); ingredient freshness (milk, meat, etc.); frying oil (viscosity and chemical make-up) and food quality including taste (electronic nose).

The conventional analytical methods for assessing quality and safety are very tedious, time consuming and require skill. Therefore there is a need to develop quick, sensitive and reliable techniques for quick monitoring of food quality and safety. This can be overcome by the application of sensor automation technique in the food processing industries. Sensors are components that are used to measure, monitor and control parameters such as temperature, pressure, liquid levels etc. for proper functioning of a food processing plant. They transform real magnitude into an electric signal transmitted to human readable display system. Sensors are of two types i.e., at line sensors and on line sensors. Common applications of sensor in the food processing include process monitoring, shelf-life investigation, freshness evaluation, quality control etc.

Sensors used in food processing industries Due to their high level of functionality or application different sensors are used in the food processing industries which are explained below:

Thermo-sensors