Influence of Structure on Saltiness and Sweetness of Dehydrated Food Products

Abstract

Pore structure of foods influences the quality and texture of dehydrated food products. The development of food products with different pore structures and its effect on the sensory characteristics of the products were investigated. Potatoes and bananas were osmotically pre-treated using salt and sucrose solutions, respectively, and dehydrated with various drying methods, such as air drying, freeze drying, and vacuum drying, in order to obtain different pore structures. Simple mathematical models were developed in order to correlate the structural properties with process conditions. Depending on the drying method, porosity varied from 5% to 75% for potatoes and from 15% to 60% for bananas. Porosity was higher for the samples that were freeze-dried at lower pressures, followed by samples freeze-dried at higher pressures and, finally, vacuum- and air-dried samples. The surface areas of the dried samples varied between 0.961 and 3.040 m²/g, which are typical values for dehydrated foods. Freeze-dried potatoes and bananas were found to be saltier and sweeter (Score 6.5–7.8), respectively, than air- and vacuum-dried products (Score 4.8–5.8). Bananas and potatoes with the highest porosity and the highest specific surface areas presented more intense taste, providing the opportunity of reducing the levels of salt and sugar of the produced products without affecting the salty or sweet taste.

Keywords:

• Freeze drying
• Osmotic dehydration
• Porosity
• Saltiness
• Specific surface area
• Sweetness

ACKNOWLEDGMENT

The project was funded by the John S. Latsis Public Benefit Foundation. The sole responsibility for the content lies with its author(s).