Effect of pulsed electric field treatment on the kinetics of rehydration, textural properties, and the extraction of intracellular compounds of dried chickpeas

Abstract

This study investigated the effect of pulsed electric fields (PEF) pretreatment on rehydration kinetics, firmness, and release of intracellular components of dried chickpeas during rehydration at 35 to 65°C. After soaking preconditioning, chickpeas were subjected to PEF treatments (2.5 and 3.3 kV/cm, 0.2 to 12.0 kJ/kg, 15 µs pulse width, 20 Hz frequency). PEF treated and untreated chickpeas were dried in crossflow air dryer and their rehydration at constant seed/water ratio of 1:5 was studied for 24 hr. During rehydration, moisture, firmness, and concentration of released proteins, carbohydrates and raffinose family oligosaccharides (RFO) were determined and described using appropriate mathematical models. PEF treatment led to up to 70% higher rehydration rates of dried chickpeas. This increase corresponds to rehydration time of approximately 1.5 hr, as opposed to 5 hr for untreated samples. Firmness of PEF treated chickpeas (for energy inputs higher than 3 kJ/kg) during rehydration decreased up to 30% compared to untreated samples. The firmness of untreated samples after 300 min of rehydration was achieved at much shorter times (up to 30 min) for PEF treated samples. At the end of 300 min of rehydration, more than 47.7%, 76.1%, and 86.6% of total raffinose, stachyose, and verbascose, respectively has been extracted, but only 0.03% of nutritionally valuable proteins from PEF treated chickpeas. Consequently, this study demonstrates that PEF processing could be implemented in dried chickpeas processing as pretreatment, for the reduction of rehydration time prior to cooking and of intestinal discomfort caused by RFO.

Combined effect of pulsed electric field and osmotic dehydration pretreatments on mass transfer and quality of air‐dried pumpkin

“…Air‐drying energy consumption ( W DR ) was evaluated for all studied samples, in order to estimate the potential energy savings obtained from the use of either OD or PEF as pretreatments or the combined effect of PEF and OD processes before air‐drying. The W DR was calculated as a ratio of the total energy consumed to achieve 80% moisture reduction, according to Equation (8) (Andreou et al., 2021a,b): $$\begin{equation}{W_{{\rm{DR}}}} = \frac{{A \cdot v \cdot {\rho _{{\rm{air}}}} \cdot {t_{{\rm{AD}}}} \cdot {{\Delta}}T \cdot {C_{\rm{p}}}}}{{{m_0}}}\;\end{equation}$$where A = 0.2886 m 2 , v = 1.5 m/s, ρ air (at 60°C and atmospheric pressure, 1 atm) = 1.029 kg/m 3 , C p (at 60°C and atmospheric pressure 1 atm) = 1.009 kJ/kg/K, and m 0 = 0.3 kg.…”

“…The cost of OD process was estimated at the selected optimal conditions (55 • C, 120 min, 1/5 (ws/w OD ) and formulation of OD solution (40% glycerol, 10% trehalose, 10% galacto-oligosaccharides, 2.0% ascorbic acid, 2.0% sodium chloride, and 1.5% calcium chloride in strained yoghurt whey). It was estimated that the OD solution cost would be approximately 0.33€/kg fresh pumpkin, assuming that the reconstitution of OD solution would be at least 5 times, as suggested by literature (Andreou et al, 2021a(Andreou et al, , 2021b. The total cost of the OD process was estimated at approximately 0.35€/kg pumpkin.…”

Application of emerging thermal and nonthermal technologies for improving textural properties of food grains: A critical review

“…Limitations in the large-scale application of PEF treatment of food grains and the way forward A recent study observed that thermal processing above 90 • C without calcium addition should be avoided to prevent the severe degradation of texture parameters (up to 70%) of PEF-treated beans due to loss of structural integrity caused by increased temperature (Alpos et al, 2022). From an industrial perspective, the production of legumes with a decreased rehydration time before cooking and the simultaneous release of undesirable carbohydrates is expected to have a higher level of customer acceptance (Andreou et al, 2021). Moreover, PEF treatment can destroy cell membranes and alter the mechanical properties of plant tissues, leading to changes in their physical and textural properties.…”

“…In another study, PEF pretreatment resulted in softening of chickpea tissues owing to a faster rate of water uptake during rehydration. With the increasing intensity of PEF treatment (> 3.6 kJ/kg), the firmness of samples rapidly decreases (Andreou et al., 2021). Amylolytic enzymes hydrolyze the glycosidic linkages in starch to produce soluble maltose and glucose (Barman & Dkhar, 2015).…”

Ozone treatment promotes physicochemical properties and antioxidant capacity of fresh-cut red pitaya based on phenolic metabolism

“…Postharvest treatment plays an important role in improving the storage life of fruits and vegetables. Pulsed electric fields ( 5 ), heating ( 6 ), cold plasma technology ( 7 ), edible coating ( 8 ), and pulsed light ( 9 ) are some of the emerging technologies for postharvest treatments. Currently, attention is focused on ozone as a powerful antibacterial agent, characterized by rapid decomposition and oxidation, and is approved by the U.S. Food and Drug Administration as an antibacterial additive in direct contact with food.…”