Sun-Dried Tomato Drying – Parameters for Industrial Production of Consistent Tomato Slices

Sun-Dried Tomato Drying – Parameters for Industrial Production of Consistent Tomato Slices

Sun-Dried Tomato Drying Machine

Fresh tomatoes for sun-dried processing start with 90–94 % moisture on a wet basis. They are typically sliced and dried to a final moisture of 5–10 % to reach a water activity below 0.6 for microbial stability and long shelf life.

The high sugar and acid content, combined with lycopene as the primary pigment, makes temperature control critical.

Lycopene degrades with excessive heat or prolonged oxygen exposure, while uneven drying leads to case hardening or inconsistent color.

Traditional open-sun drying relies on ambient conditions but introduces variability in moisture, color, and hygiene.

For industrial production that replicates the characteristic appearance and quality of sun-dried tomatoes, controlled low-temperature drying provides repeatability.

Heat pump dryers maintain stable chamber conditions at 45–60 °C with dehumidification, minimizing lycopene loss while achieving uniform moisture removal across slices.

Mesh belt dryers support continuous throughput for higher volumes with similar temperature profiles. These methods align with the need for bright red color, retained lycopene, and rehydration performance required in final products.

Pre-processing includes washing whole tomatoes, slicing to 4–8 mm thickness for even drying, optional light salting or citric acid dip to reduce browning, and draining excess surface water. Uniform slice thickness directly affects drying time and final moisture distribution.