Puja
Das
ab,
Prakash Kumar
Nayak
a and
Radha krishnan
Kesavan
*a
aDepartment of Food Engineering & Technology, Central Institute of Technology, Deemed to be University, Kokrajhar, B.T.R. Assam 783370, India. E-mail: k.radhakrishnan@cit.ac.in; Tel: +91-7002909335
bDivision of Research and Innovation, Uttaranchal Institute of Technology, Uttaranchal University, Dehradun 248007, Uttarakhand, India
First published on 13th August 2025
The present study focuses on an extensive investigation into thermosonication as a novel process for enhancing the extraction of bioactive functional compounds from lapsi fruit juice. Process optimization was achieved by using artificial neural networks (ANN) coupled with a genetic algorithm (GA), finding optimum conditions to be 75% amplitude, 40 °C, and 60 minutes. The release performance of principal functional compounds, such as total phenolic content, total flavonoid content, antioxidant activity, and ascorbic acid, was also investigated under these optimized conditions. Among all the kinetic models used, the pseudo-second-order model demonstrated the best correlation (R2 = 0.99, χ2 = 0.09), which indicated that compound release occurred by chemisorption processes. The process also revealed an initial rapid extraction phase, which was then followed by a steady plateau at 60 minutes. The activation energies were in the range of 29.45 to 35.23 kJ mol−1, and this indicated the temperature dependence of the process. Thermodynamic studies revealed that the extraction was spontaneous under all tested temperatures (ΔG: −5.45 to −18.46 kJ mol−1), endothermic in nature (ΔH: 5.44 to 15.64 kJ mol−1), entropy-guided (ΔS: 18.03 to 57.23 J mol−1 K−1) and, therefore, capable of efficiently breaking down the cell walls and facilitating mass transfer. Optimal extraction efficiency was achieved at 40 °C, beyond which heat-induced degradation of labile compounds was observed. Kinetic and thermodynamic studies confirm that thermosonication enables efficient, spontaneous, and temperature-dependent extraction of bioactives from Lapsi juice. The findings support its feasibility for energy-efficient, scalable industrial applications.
Sustainability spotlightThermosonication is a new green technology that holds great potential in improving the nutritional and functional values of underutilized fruits, such as lapsi (Choerospondias axillaris), by supporting sustainable food processing objectives. Through the employment of synergistic combinations of mild heat and ultrasonic waves, this method supports the effective release of bioactive compounds without degradation, which is usually linked with traditional thermal approaches. Unlike using only high temperatures, thermosonication provides a more gentle and controlled extraction condition, with the added benefit of protecting heat-sensitive nutrients and thus enhancing the total yield. Its use for nutrient extraction from lapsi, a fruit native to Sikkim and the Himalayan hilly regions, highlights its potential in unearthing the value of non-conventional plant resources that are often underutilized because of market or processing constraints. By kinetic and thermodynamic modeling, this work gives better mechanistic insights into the mass transfer behavior, energy demand, and compound stability during processing, which are the factors critical to assessing its potential for industrial scalability. Results show that careful control of parameters like temperature and sonication amplitude is important in achieving maximum efficiency without compromising the product quality. Therefore, this study not only emphasizes the technological strengths of thermosonication but also opens the doors for the widespread implementation of sustainable, nutrient-protecting technologies in food supply chains. Finally, this study promotes the translation of regional biodiversity into viable food innovations that benefit the human health as well as environmental sustainability. |
A lesser-known fruit, lapsi (Choerospondias axillaris), is indigenous to Nepal, Bhutan, and some states of Northeast India, including Arunachal Pradesh, Sikkim, and Assam.6 The lapsi tree bears tiny, light-greenish blooms at the start of spring, followed by tiny, oval fruits that are around two to three centimeter in diameter. The fruit has a sour, tangy flavor and turns yellow or crimson when it is fully mature. It contains a variety of nutrients (such as dietary fiber, vitamin C, and vitamin A), has several health advantages, and is well-known for its anti-inflammatory, antibacterial and antioxidant qualities.7 In order to comprehend the improved extraction of bioactive components when heat and ultrasonic waves are applied to plant materials, the complicated topic of extraction kinetics of thermosonicated juices integrates concepts from thermodynamics, mass transport processes, and sonochemistry.2 To describe the kinetics of thermosonication-based extraction, researchers have used a variety of mathematical models (Table 1). The industrial application of thermosonication technology is greatly advanced by the use of kinetic models, which allowed for process optimization, better quality control, and economical scale-up strategies for manufacturing excellent, nutrient-rich juices that retain the bioactive substances from fruits and vegetables and offer a prolonged shelf life.8
Model name | Equations | Terms | Reference |
---|---|---|---|
Second order model |
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K is the pseudo-second-order extraction rate constant, Ct is the extract amount at time t (g L−1), and Ce is the equilibrium concentration (g L−1) | 27 |
Two-site kinetic model |
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M t and M∞ are concentrations of the extracted compound at time t and infinity, F is the fraction of solute released during rapid extraction, (1 − F) represents the portion of solute released during slower extraction, and k1 and k2 are the first-order rate constants that represent the two stages of the extraction process | 28 |
Peleg's model or hyperbolic model |
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k 1 is the Peleg's rate constant at the beginning of the extraction, and k2 is Peleg's capacity constant | 29 |
Fick's model |
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M t and M∞ are concentrations of the extracted compound at time t and infinity, D is the effective diffusion coefficient, and R is the radius | 30 |
Parabolic diffusion model | y = A0 + A1t1/2 | A 0 is the washing coefficient, which indicates the amount of extract extracted instantaneously; A1 is the diffusion rate constant | 31 |
First-order reaction model |
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K is the first-order extraction rate constant, Ct is the amount extracted at time t (g L−1), and Ce is equilibrium concentration (g L−1) | 32 |
Thermodynamic examination of the thermosonication processes entails important parameters, including enthalpy change (ΔH), entropy change (ΔS), and Gibbs free energy change (ΔG). The change in enthalpy (ΔH) is linked with the energy for breaking and forming bonds during the processes. The change in entropy (ΔS) indicates the increase in molecular disorder because of cell disruption. Gibbs free energy change (ΔG) defines the spontaneity of the extraction process and the equilibrium of the reaction. Furthermore, compared with traditional approaches, thermosonication generally lowers the activation energy (Ea) by 15–30%, thus improving the efficiency of the extraction reactions.9 Thermodynamics constants exhibit non-Arrhenius behaviour at the water–solid interface where cavitation effects are most noticeable, are proof that thermosonication modifies reaction pathways by offering substitutes with lower energy barriers.10 In contrast to traditional thermal processing methods, the energy efficacy of thermosonication comes from its capacity to concentrate energy in microscopically precise locations where cell disruption occurs.11 This results in significantly higher extraction yields despite the lower overall electrical inputs; studies have shown savings in energy consumption of 20–45% while accomplishing similar or better extraction of bioactive substances.12 Enhancing the power-to-mass ratio, controlling the loss of heat during sound energy conversion, striking a balance between the residence duration and energy intensity, and creating accurate mathematical models that can forecast phase changes and compound stability under various thermosonication conditions are examples of practical thermodynamic factors in industrial applications.13
The significance of this research extends beyond lapsi fruit to the broader context of underutilized plant resources. Globally, numerous fruits and vegetables remain underexploited due to the challenges in processing and market integration. Thermosonication offers a versatile platform to valorize such resources, aligning with the Sustainable Development Goals by reducing the waste, enhancing the nutritional availability, and promoting the biodiversity in food systems.14 For lapsi, the application of TS not only addresses these goals but also taps into its cultural and economic potential in regions where it is a traditional staple. However, realizing this potential requires a detailed understanding of how TS influences the extraction process at a mechanistic level, which is the focus of this study. Kinetic models, such as the pseudo-second-order model and Fick's diffusion model, have been widely used to describe the solid–liquid extraction in food systems, but their adaptation to TS-processed juices, in which liquid–liquid interactions also play certain roles, remains underexplored.15 Similarly, thermodynamic analyses have been applied to ultrasound-assisted extraction of phytochemicals from herbs and seeds, revealing endothermic processes with positive entropy changes, but data that are specific to fruit juices under TS conditions are limited.
This study builds directly on the foundation laid by an ANN-GA optimization, extending the investigation to the extraction kinetics and thermodynamics of thermosonicated lapsi juice.16 Herein, kinetic models such as pseudo-second-order, Peleg's, two-site kinetic, pseudo-first-order, parabolic diffusion, and Fick's models were employed to characterize the extraction rates and patterns, complemented by thermodynamic calculations of ΔH, ΔS, and ΔG to assess process feasibility and compound behavior.17 The choice of these models is based on their proven applicability in food extraction studies and their ability to capture the complex interplay between ultrasound and heat in TS. The experimental design focuses on a temperature range of 30 °C to 50 °C, with measurements taken at 5 minutes intervals for up to 60 minutes and maintaining the optimized 75% amplitude.
A mutation rate of 0.02 was applied, introducing small, random alterations to the solutions. This low rate ensured that the population maintained diversity and avoided getting trapped in the local optima, allowing the algorithm to explore beyond the immediate vicinity of current solutions without excessively disrupting the evolutionary progress. The GA iterated over 300 generations, providing ample opportunity for the population to evolve toward an optimal solution.18
Given that GA is oriented towards minimizing the fitness function, eqn (1) was minimized to achieve the optimization objective.19
![]() | (1) |
In the context of GA optimization, Y denotes the juice quality attributes predicted by the ANN model, while F stands for the fitness function.
The pseudo-second-order model proved to be suitable and apparent during the extraction studies of different products.3,34,38Eqn (2) presents the kinetic model that was used to calculate the extraction rate of functional compounds in TSLJ.
![]() | (2) |
Boundary conditions: y = 0 at t = 0; y = y at t = t.
Under these boundary conditions, eqn (3) can be formulated from the pseudo-second-order model given in eqn (2).
![]() | (3) |
Further, eqn (3) can be simplified into a linear form, as presented in eqn (4)
![]() | (4) |
![]() | (5) |
![]() | (6) |
Gibbs free energy provides a deeper understanding of the energy changes occurring during the process, aiding the optimization of conditions, such as temperature, time, and sonication intensity, for achieving maximal efficiency.9 This optimization not only enhances extraction yields but also ensures that energy is used efficiently, contributing to sustainable processing practices. The standard free energy of formation (ΔG°) of a compound is a measure of the stability of that compound compared with its elements in their standard states. It can be estimated using the standard enthalpy of formation (ΔH°) and standard entropy (S°) of the compound according to eqn (7).
ΔG° = ΔH° − TΔS° | (7) |
The thermodynamic characteristics of the solute extraction were studied by calculating ΔG°, ΔH°, and ΔS°. Eqn (8) presents the Gibbs free energy (thermodynamic) equation.
ΔG° = −RT![]() ![]() | (8) |
Eqn (9) presents the van't Hoff equation, which was used to calculate ΔH° and ΔS° by combining eqn (7) and (8):
![]() | (9) |
![]() | (10) |
EPs denotes the functional compounds extracted after 30 minutes of ultrasonic extraction at temperature T (K), while EPmax denotes the functional compounds retrieved after comprehensive extractions with optimal sonication time, temperature, and amplitude.
R 2 (coefficient of determination) shows the percentage of variance in the experimental data accounted for by the model. The values nearest to 1 imply a good fit. MSE (mean square error) is a quadratic estimate of the error and gives more weight to larger differences than MAE. It can be helpful in determining which models generate large outliers. χ2 (chi-square statistic) measures the agreement between the predicted and experimental values in terms of the scale of the experimental values. Lower values correspond to better agreement of the model with the experimental data.
![]() | (11) |
![]() | (12) |
![]() | (13) |
The variables utilized in this context are ei for experimental data, pi for predicted values, n for the total number of observations, p for the mean value of the predicted data and e for the mean value of the experimental data. EP stands for extracted functional compounds.
Fig. 1 depicts the hybrid artificial neural network (ANN) and genetic algorithm (GA) system designed to optimize the thermosonication process parameters, namely, the sonication amplitude (X1), temperature (X2), and time (X3). The ANN predicted values for process outcomes, including the yield of bioactive functional compounds, were initially derived with ANN modeling utilizing the input–output relations learned from the network training. These forecasts were then combined with the genetic algorithm, which was used to train the ANN weights and biases to minimize the fitness function, maintaining the forecasted outputs within ±0.044 of the target values.36,37 The GA used standard evolutionary procedures, such as population initialization, fitness assessment, selection, crossover, mutation, and convergence, to achieve the optimal solutions. This combined ANN–GA method improved the predictive accuracy and global optimization, and hence, it was very efficient for the modeling and optimization of sophisticated nonlinear processes, such as thermosonication.
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Fig. 1 Artificial neural network (ANN) and genetic algorithm (GA) framework developed to optimize the thermosonication process parameters. |
Fig. 2 demonstrates the convergence pattern of the genetic algorithm (GA) for the optimization of the thermosonication parameters obtained from the ANN model-predicted values. The y-axis was plotted with fitness values, where greater negative values signified improved model fitting, and the x-axis was plotted with the number of generations.38 The best fitness and mean fitness values initially oscillated around −3.2 with a restricted improvement. Nonetheless, there was a steep decline in the mean fitness at the 200th generation, tending towards the optimal value of −3.4. The optimum fitness was obtained at 75% amplitude, 40 °C temperature, and 60 minutes of sonication time, as annotated on the graph. The steady low fitness variation in values thereafter proves the stability and efficacy of the optimisation process.15
Sl. no | Model | χ 2 (×10−2) | R 2 | RMSE |
---|---|---|---|---|
a Abbreviations: R2 = Coefficient of determination; RMSE = root mean square error; χ2 = chi-square statistics. | ||||
1 | Pseudo second-order model | 0.93 | 0.98 | 0.03 |
2 | Pseudo first-order model | 1.35 | 0.93 | 0.37 |
3 | Peleg's model or hyperbolic model | 1.54 | 0.88 | 0.30 |
4 | Two-site kinetic model | 1.92 | 0.83 | 0.38 |
5 | Fick's model | 2.89 | 0.80 | 0.41 |
6 | Parabolic diffusion model | 2.96 | 0.80 | 0.40 |
Extraction kinetics demonstrated R2 values of 0.99, 0.99, 0.99, and 0.99 with the lowest χ2 values, and Ea values of 32.04, 35.23, 30.09, and 29.45 for TPC, TFC, AOA and AA, respectively. A pseudo-second-order model was employed to examine the characteristics of the model for EPP, EPF, EPAOA, and EPA (Fig. 3–6).40 All the responses exhibited a rapid initial increase with rising temperature and extraction time during the early stages of the TS process.41 This was followed by a more gradual rise, eventually plateauing towards the end of the extraction process, approximately after 55–60 minutes, reaching a saturation stage.42
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Fig. 3 Pseudo-second-order kinetic plot for the total phenolic content extracted from TSLJ at different ultrasonication temperatures. |
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Fig. 4 Pseudo-second-order kinetic plot for the total flavonoid content extracted from TSLJ at different ultrasonication temperatures. |
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Fig. 5 Pseudo-second-order kinetic plot for the ascorbic acid content extracted from TSLJ at different ultrasonication temperatures. |
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Fig. 6 Pseudo-second-order kinetic plot for the antioxidant activity of TSLJ at different ultrasonication temperatures. |
TPC increased with time at all temperatures, with the maximum extraction efficiency at 40 °C, followed by 50 °C and 30 °C. This trend suggested that a moderate heat input (40 °C) increased the phenolic compound solubilization and diffusion, probably due to better cell wall permeability and penetration of the solvent, while a high heat (50 °C) resulted in partial degradation or structural rearrangement, which lowered the extractability.44 The PSO model was a good fit for the data over all temperatures, indicating that the extraction process is governed by chemisorption phenomena, and the slowest step occurs via chemical bonding interaction rather than diffusion alone. The high predictability of the model highlights its applicability to modeling the extraction behavior of phenolics under various thermal conditions, which is essential for process parameter optimization in functional foods and nutraceuticals.
The graph shown in Fig. 3 depicts the pseudo-second-order kinetics of the extraction of TPC from thermosonicated lapsi juice, with a rapid initial increase at 40 °C due to ultrasonic cavitation disrupting the cell walls, followed by a plateau caused by diffusion limitations and potential thermal degradation at 50 °C, which reduces the extraction rate.45 This reflects a mechanism where thermosonication enhances the mass transfer by breaking down the plant matrix, with temperature influencing the balance between the compound release and stability.
Ascorbic acid extraction is highly dependent on time and temperature, as reflected in the graph. In the beginning, the content of ascorbic acid increased exponentially as a result of the rapid release of surface-bound molecules and effective penetration by the solvent, but later on (after 30–40 minutes), the rate of extraction tended to decrease and plateau, signifying equilibrium.47 Temperature is an important parameter influencing this behavior, and extraction at 40 °C yielded the maximum ascorbic acid content, most probably due to increased diffusion and cell membrane permeability without much degradation. At 30 °C, the lower temperature caused retardation in mass transfer and yield, whereas at 50 °C, while diffusion might be quicker, thermal degradation of heat-sensitive ascorbic acid takes place most probably, lowering the final content.48 These findings emphasize the need for optimizing the extraction temperature and time for maximal recovery with minimal nutrient loss, with 40 °C identified as the best extraction temperature condition in this work.
Both the saturation concentration (Sc) of functional compounds in the liquid extract and the pseudo-second-order rate constant (k) increased at 40 °C for all the four responses. The SC values were in the following ranges: TPC (85.89–592.50 mg GAE per mL), TFC (126.64–200.61 mg QE per mL), AOA (57.02–108.01%) and AA (59.63–68.77 mg/100 mL). The k value ranges were found to be as follows: TPC (0.00003–0.00009 mg GAE per mL), TFC (0.00003–0.00008 mg QE per mL), AOA (0.00013–0.00061%) and AA (0.00004–0.00013 mg/100 mL) (Table 3).50 The rise in Sc with increasing temperature could be linked to the dynamic interactions between the juice and cell matrix of the sample. The rate constant also increased with temperature, possibly due to the greater thermal energy required for the extraction of EP.51 Escalating saturation concentrations and rate constants were observed in the extraction of antioxidant compounds, which were comparable with those of the trends observed during the microwave-assisted extraction of fenugreek leaves52 and bioactive compounds of moringa leaves9 within the 30–45 °C temperature range.
Response | Temperature | k | S C | χ 2 (×10−2) | R 2 | RMSE | E a (kJ mol−1) |
---|---|---|---|---|---|---|---|
a Abbreviations: Temperature 30, 40 and 50 °C, TPC = total phenolic content; TFC = total flavonoid content; AOA = antioxidant activity; AA = ascorbic acid; R2 = Coefficient of determination; RMSE = root mean square error; χ2 = chi-square statistic; k = pseudo-second-order rate constant; SC = saturation concentration; and Ea = activation energy. | |||||||
TPC | 30 °C | 9 × 10−5 | 85.89 ± 3.03 | 1.19 | 0.98 | 0.30 | 32.04 |
40 °C | 3 × 10−5 | 592.50 ± 1.81 | 1.47 | 0.99 | 0.33 | ||
50 °C | 8 × 10−5 | 334.39 ± 1.44 | 1.44 | 0.99 | 0.33 | ||
TFC | 30 °C | 3 × 10−5 | 126.64 ± 2.84 | 1.16 | 0.98 | 0.29 | 35.23 |
40 °C | 5 × 10−5 | 200.61 ± 44.66 | 0.12 | 0.99 | 0.09 | ||
50 °C | 8 × 10−5 | 160.13 ± 3.85 | 1.04 | 0.98 | 0.28 | ||
AOA | 30 °C | 2 × 10−4 | 57.02 ± 1.25 | 2.83 | 0.98 | 0.46 | 30.09 |
40 °C | 1 × 10−4 | 108.01 ± 1.51 | 1.30 | 0.99 | 0.31 | ||
50 °C | 6 × 10−4 | 57.17 ± 1.92 | 3.66 | 0.96 | 0.53 | ||
AA | 30 °C | 4 × 10−5 | 62.29 ± 2.92 | 1.21 | 0.98 | 0.30 | 29.45 |
40 °C | 1 × 10−4 | 68.77 ± 2.10 | 0.78 | 0.99 | 0.24 | ||
50 °C | 7 × 10−5 | 59.63 ± 2.40 | 3.57 | 0.98 | 0.52 |
Data fitting to the pseudo-second-order model in this study indicates that the extraction process of bioactive compounds from LJ followed a pseudo-second-order kinetic behaviour. This finding is crucial as it provides insights into the mechanisms underlying the extraction process.53 The high R2 values (>0.99) obtained for TFC, AOA, TPC and AA at 40 °C suggested that the model accurately fitted with the experimental data, indicating a strong correlation between the predicted and observed values. This indicated that the extraction process was well-described by the pseudo-second-order model, and temperature had a significant impact on the extraction kinetics.2 The activation energy values obtained for the four responses (TPC, TFC, AOA, and AA) were around 29.45 to 32.04 kJ mol−1, suggesting that similar energy inputs were required for the extraction of these compounds. This implied that the extraction mechanisms of these compounds were likely similar, possibly involving similar rate-limiting steps, such as diffusion through the cell walls or desorption from solid particles.54 The consistency of the Ea values across different compounds further supported this hypothesis.
The increase in saturation concentration (Sc) at the temperature of 40 °C can be explained by the greater thermal energy available at 75% amplitude. This increased thermal energy helped in breaking down the cell matrix of the sample more effectively, leading to greater release of functional compounds into the liquid phase. As the temperature increased, the molecules in the sample gained more kinetic energy, which enhanced the mobility of the compounds within the sample and promoted their diffusion into the liquid phase.33 This increased mobility and diffusion rate resulted in higher saturation concentrations of the compounds in the liquid phase. Similarly, the increase in the rate constant (k) with temperature reflected the greater thermal energy requirement for the extraction process.9 The rate constant is a measure of the speed of the extraction process, with higher values indicating a faster rate of extraction. As the temperature increased, more thermal energy was available to drive the extraction process, leading to a higher rate constant. This suggested that the extraction process became more efficient at higher temperatures as more compounds were extracted in a shorter period due to the increased thermal energy, facilitating the breakdown of the cell matrix and release of the compounds.9
Response | Temperature | ΔH (kJ mol−1) | ΔS (J mol−1 K−1) | ΔG (kJ mol−1) |
---|---|---|---|---|
a Abbreviations-ΔH: Enthalpy; ΔS: Entropy; ΔG: Gibbs free energy. | ||||
TPC | 30 °C | 15.01 | 28.63 | −8.65 |
40 °C | −8.94 | |||
50 °C | −9.23 | |||
TFC | 30 °C | 7.22 | 25.03 | −7.57 |
40 °C | −7.82 | |||
50 °C | −8.07 | |||
AOA | 30 °C | 15.64 | 57.23 | −17.32 |
40 °C | −17.89 | |||
50 °C | −18.46 | |||
AA | 30 °C | 5.44 | 18.03 | −5.45 |
40 °C | −5.63 | |||
50 °C | −5.81 |
The enthalpy change (ΔH = 7.22 kJ mol−1) for TFC extraction indicated a lower energy requirement compared to TPC, reflecting the different molecular structures and extraction mechanisms of flavonoids.55 The entropy change (ΔS = 25.03 J mol−1 K−1) also pointed to a moderate increase in system disorder. The negative ΔG values across all the temperatures, ranging from −7.57 kJ mol−1 to −8.07 kJ mol−1, confirmed the spontaneity of the extraction process (Table 4). The more negative ΔG values at higher temperatures suggested that increasing the temperature enhanced the extraction efficiency of flavonoids in TSLJ.56
For AOA, the thermodynamic parameters revealed a significantly higher enthalpy change (ΔH = 15.64 kJ mol−1) compared with TFC, indicating a higher energy requirement for the release of antioxidant compounds. The entropy change (ΔS = 57.23 J mol−1 K−1) was notably higher, suggesting a substantial increase in molecular disorder during the extraction process.57 Gibbs free energy (ΔG) values were strongly negative, ranging from −17.32 kJ mol−1 to −18.46 kJ mol−1, indicating a highly favorable and spontaneous extraction process (Table 4). The increasingly negative ΔG values with rising temperature affirmed that higher temperatures promoted the efficient extraction of antioxidant compounds during thermosonication.58
For ascorbic acid, the enthalpy change (ΔH = 5.44 kJ mol−1) was the lowest among all the responses, indicating minimal energy requirements for its extraction. The entropy change (ΔS = 18.03 J mol−1 K−1) reflected a modest increase in molecular randomness. The negative ΔG values, ranging from −5.45 kJ mol−1 to −5.81 kJ mol−1, confirmed the spontaneity of the extraction process (Table 4).59 However, the smaller magnitude of ΔG compared with TPC, TFC, and AOA suggested that the spontaneity of ascorbic acid extraction was less temperature-dependent, likely due to its inherent solubility and stability under thermosonication conditions.
The thermodynamic parameters for TSLJ demonstrated that the extraction of TPC, TFC, AOA, and AA during thermosonication was spontaneous at all the studied temperatures, with increasingly favorable ΔG values at higher temperatures. TPC and AOA exhibited higher ΔH, indicating greater energy requirements, while TFC and AA required comparatively less energy for extraction. The positive ΔS values across all the responses suggested that the thermosonication process increases the molecular randomness, likely due to the breakdown of cellular structures and enhanced mass transfer.60 These results highlighted the efficacy of thermosonication in facilitating the extraction of bioactive compounds from lapsi juice, with temperature playing a crucial role in optimizing the yield and efficiency.
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