Low frequency ultrasound pretreatment of carrot slices: Effect on the moisture migration and quality attributes by intermediate-wave infrared radiation drying

Abstract

The effect of low frequency ultrasound (LFU) pretreatment prior to intermediate-wave infrared radiation (IW-IR) drying on water migration and quality attributes of carrot slices was investigated in this study. Results showed that the vacuole water of LFU pretreated carrot samples decreased, while the cytoplasm and intercellular space water increased by low-field nuclear magnetic resonance analysis. In addition, LFU pretreatment caused the disruption of cell structures and formation of micro-channels, resulting in significant (p<0.05) decrease of drying time required. The IW-IR dried carrot slices with LFU pretreatment showed higher β-carotene content and rehydration ratio in comparison with control samples. The color parameters of ultrasound pretreated dried carrot slices after dehydration were closer to the raw carrot samples. The results of electronic nose showed that the aromatic and volatile organic compounds of dried carrot increased by sonicated pretreatment, while the nitrogen oxides decreased, indicating that LFU can improve the flavor of dried carrot slices.

Effects of Various Nonthermal Pretreatments on the Physicochemical Properties of Dried Ginger (Zingiber officinaleRoscoe) Slices from Two Geographical Locations

“…() used the Weibull model to describe the drying behavior of red bell pepper and established that the R 2 was greater than 0.99, chi‐square values were below 0.001, and with the least RMSE. These results are in agreement with what has been previously reported by other researchers for red bell pepper (Wang et al., ) and cucumber (Kiani et al., ).…”

Optimization of osmosonication pretreatment of ginger (Zingiber officinaleRoscoe) using response surface methodology: Effect on antioxidant activity, enzyme inactivation, phenolic compounds, and physical properties

“…In the current study, the increase in SG with high PT and low UF (Figure e) can be attributed to the ultrasonic cavitation, which permeated the cell membrane and enhance the mass transfer of water and solid from the ginger sample. This result is consistent with the findings of Wang et al (), who revealed that low application of US frequency enhanced SG of carrot sample. The quadratic model that depicts the link between SG and the OS parameters are below (Final Equation in Terms of Coded Factors): …”

“…The RR was measured according to Wang, Xu, Wei, and Zeng () in Equation 6: where W 1 (weights of the samples before rehydration) and W 2 (weights of the samples after rehydration) were measured, respectively.…”

Application of non‐thermal pretreatment techniques on agricultural products prior to drying: a review

“…Consequently, the authors proposed that this could be interesting for the preservation of phenolic compounds and the antioxidant activity when high‐density US and lower drying temperature are applied. Wang et al ., also showed that the application of US enhanced the convective drying process as shown in Table . Cruz et al ., stated that the use of US pre‐dehydration prior to drying of grapes and plums increases drying rate, and drying kinetics as well as improves the physical properties and the general quality aspects of the final products.…”

“…Several works have been done to assess the influence of US pretreatment preceding drying on the physicochemical properties and microstructural alterations of various products. One of the important physical parameters of dehydrated product that enhance consumer acceptance and ensure microbiological stability is the total colour change and water activity respectively . Kroehnke et al ., studied the influence of US pretreatment on convective drying of potato and reported that the total colour change of dried potato significantly decreased when US was applied.…”