Effect of postharvest storage on potato (Solanum tuberosum L.) texture after pulsed electric field and thermal treatments

Pulsed electric field (PEF) and mild thermal pretreatments at 60 degrees C (T60) may help preserve texture of plant tissue during thermal processing through pectin modification. However, potato starch may counteract the adhesive role of pectin during thermal processing. Furthermore, postharvest storage of potatoes may result in compositional and textural changes. Therefore, the effect of postharvest storage on potato composition and on texture of untreated, PEF treated and thermally treated tissue was studied. The composition remained unchanged (p-value <0.05), whereas the fresh tissue hardness slightly decreased (p-value <0.0001-0.1387) during storage. Prolonged storage resulted in a softer texture after PEF treatments with total specific energy input (WT) 0.6 kJ/ kg at electric field strengths of 0.74-1.01 kV/cm, whereas the hardness was independent of the storage time if WT 0.6 kJ/kg. Slower texture degradation at 95 degrees C was observed after T60 and, especially, PEF-T60 pretreatment, independently of the storage time.