New opportunity of using pulsed electric field (PEF) technology to produce texture-modified chickpea flour-based gels for people with dysphagia

Abstract

An aging population has driven a need for novel food products that are dysphagia-friendly but still provide adequate nutrition. This study investigated the potential of pulsed electric field (PEF) processing to create gels with varied textures from a chickpea flour slurry (10 % w/w). PEF treatment at 1 or 2 kV/cm and 410–500 kJ/kg induced the formation of soft gels after overnight cooling (24 h, 4 °C). As specific energy increased, the hardness of the gels rose (0.35 ± 0.01 to 2.94 ± 0.19 kPa), along with notable increases in rheological properties, including storage modulus (195 ± 42 to 2350 ± 466 Pa) and yield stress (5.7 ± 5.6 to 423.4 ± 135.2 Pa) of the gels, with textures spanning a range of International Dysphagia Diet Standardisation Initiative levels. However, no differences in these parameters were observed between the two field strengths. Fourier transform infrared spectra and light microscopy revealed that gel formation was mainly attributed to starch gelatinisation (1047/1021 ratio decreased from 0.759 ± 0.007 to 0.699 ± 0.002) caused by a temperature increase due to the Joule effect during PEF, while protein denaturation and aggregation became important in PEF-treated chickpea slurries above 450 kJ/kg, resulting in a more solid-like gel formation. Importantly, gels formed following treatment at 2 kV/cm led to an increase in readily digestible starch (16.28 ± 0.15 to 89.06 ± 1.78 %) and a faster intestinal protein digestion rate (1.16 ± 0.20 × 10⁻² to 1.65 ± 0.04 × 10⁻² min⁻¹) during simulated gastrointestinal digestion. This study demonstrated the use of PEF treatment as a rapid method (44.4–227.4 ms) to produce gels with varying textural and rheological consistencies using a single ingredient, e.g. chickpea flour.