The effect of Blanching, packaging and storage period on moisture content and oil absorption in microwave-dried potato

Potato is known as a valuable source of starch which plays an important role in human nutrition. Proper storage conditions should be considered to protect the nutritional properties of potato after drying. The effect of three packaging materials (transparent biaxially oriented polypropylene laminate (BOPP); semitransparent BOPP; polyethylene-polyamide (PE-PA) laminate) in three packaging conditions (vacuum, N2, natural atmosphere) and in two temperature treatments (blanching in hot water; steam) on microwave-dried potato (Solanum tuberosum L.; Solanaceae) cubes was studied. Moisture content and oil absorption decreased in microwave dried potato by increasing storage time from 60 to 120 days. The moisture loss rate in vacuum packed samples in polyethylene polyamide film was less than BOPP. Steam blanched samples not only had more moisture but also absorbed less amount of oil. The dried and packed potatoes under nitrogen atomospher and in transparent BOPP had the highest percentage of oil absorption with 9.75% and 9.87%, respectively. Changes in the internal structure, moisture and gelatinization of starch in the surface are factors affecting the absorption of oil. Blanched samples with steam and vacuum packed in polyethylene polyamide films, have the best results in increasing the shelf-life and reducing oil absorption.