Impact of the power density on the physical properties, starch structure, and acceptability of oil-free potato chips dehydrated by microwave vacuum drying

The Effect of Pretreatments on the Physical Properties and Starch Structure of Potato Chips Dried by Microwaves under Vacuum

“…Potato samples were dried in a microwave vacuum dryer that used an inverter system to control the magnetron power outside and a rotatory vacuum chamber. Gomide et al [ 6 ] describe this equipment in detail.…”

“…Microwave energy input was gradually reduced during drying (1200-720-240-120 W), keeping the sample’s temperature below 60 °C. Power manipulation was used to obtain a high drying rate while preventing samples from not achieving the potato starch’s gelatinization range temperature, close to 69–76 °C [ 6 ], to avoid significant changes in the starch structure. Furthermore, it was guaranteed that in each moment of power reduction, the mass of the drying material was approximately equal in the three processes to ensure the same variation of power densities between them, enabling comparison.…”

“…The drying experiments were conducted using the same parameters and procedures reported by Gomide et al [ 6 ], who evaluated the impact of power density on the physical characteristics and acceptability of chips produced from raw potato slices. Thus, their experimental data were compared with those obtained in the present study for potato chips produced from pretreated samples.…”

“…Oil-free potato chips can be produced by dehydration. Microwave vacuum drying (MWVD) is a suitable process that operates at mild temperatures and results in crispy chips in shorter times than those observed for freeze- and air-drying [ 5 , 6 , 7 , 8 , 9 , 10 , 11 ].…”

“…Therefore, pretreatments that favor retrogradation can be associated with MWVD since this drying method promotes minimal starch changes when conducted below the gelatinization temperature, as reported by Gomide et al [ 6 ], who conducted MWVD of raw potatoes. However, the pretreatments that favor retrogradation with MWVD have not been reported in the literature, and are deserving to be studied as an alternative to developing tasty and healthy food.…”