Kinetics and modeling of pepsin soluble collagen (PSC) extraction from the skin of malaysian catfish (Hybrid Clarias sp.)

Abstract

The empirical kinetic models for the pepsin soluble collagen extraction from the skin of cultured hybrid catfish (Claris sp.) were studied using four two-parametric models, namely the power law, parabolic diffusion, Peleg's and Elovich's models. The Peleg's model was found to be the best model capable of predicting the extraction data with R 2 >0.9, p-value >2.0%, and RMSD <10.0%, respectively. Kinetic models based on the second order rate equation were successfully developed to describe the extraction processes with different processing variables. Extraction rate constant, initial extraction rate and equilibrium concentrations for different acetic acid concentrations, liquid to solid ratios, and pepsin dosages were predicted. The verification of the developed models showed that the experimental values agreed with the predicted ones, with percentage error differences in the range of 0.03-3.91%.

Kinetic modeling of the alkaline deproteinization of Nile-tilapia skin for the production of collagen

“…The mean-absolute-percentage errors of these two sets of experiments were ca. 4.1-4.4%, therefore the model is quite accurate and robust (Kiew et al, 2014).…”

“…The root-mean-square deviation (RMSD) and the mean-absolute-percentage error (MAPE) of the model were 0.0042 and 3.15%, respectively. Both prediction-accuracy parameters were calculated from the 135 experimental data for the alkaline pretreatment (Kiew et al, 2014), indicating that the prediction of Ct was very good. Table 3 shows the concentrations of non-collagenous protein in the liquid, measured and predicted, as well as the absolute percentage errors for ten aleatory points from the 135 experiments and for ten points outside the experimental design.…”

“…The root mean square deviation (RMSD) and the P-value were calculated to estimate the fit quality of the kinetic model (Kiew et al, 2014). A multi-objective optimization was made to obtain the maximum and minimum value for the response variables using a weighting factor of 60% for NCPE and 40% for LC, respectively.…”

“…The first step consists of the removal of NCP 2 and other impurities, such as fat from the skin, aiming to increase the collagen purity. To achieve this, 0.1 M NaOH is generally used, with different stirring times (Kiew et al, 2014;Liu et al, 2015). The second step consists of an acid extraction of the previously NaOH treated skin, commonly using 0.5 M acetic acid (Liu et al, 2015;Wang et al, 2018).…”

“…However, none of those studies included all the key optimization parameters influencing the alkaline extraction step, such as skin size and stirring speed (Li et al, 2018;Wang et al, 2018). On the other hand, there are few reports on the kinetic modelling of the acid extraction of collagen from fish byproducts (Kiew et al, 2014) based on physical and empirical methods. For instance, several authors have evaluated empirical models such as power law, parabolic diffusion, Peleg, Elovich and second-order, to describe the acid extraction of collagen from the skin of cultured hybrid catfish (Kiew et al, 2014) and Red Tilapia (Kiew and Mat Don, 2013).…”