Optimization of pectinase‐assisted extraction of Annona muricata L. juice and the effect of liquefaction on its pectin structure

Abstract

BACKGROUND: Soursop (Annona muricata L.) is an underutilized tropical and subtropical fruit with high nutritional and therapeutic benefits. This fruit is faced with enormous post-harvest losses due to its high perishability. This work was aimed to optimize the pectinase-assisted extraction conditions of soursop juice using Doehlert design and to study the effect of pectinase on its pectin structure. RESULTS: The predicted models were validated for all the responses studied and the regression coefficients ranged from 0.905 to 0.987 (P ≤ 0.05). An incubation time of 172 min, enzyme concentration of 0.04% (w/w) and incubation temperature at 42.9°C were found to be the optimal conditions for soursop juice extraction, which resulted in 75.20%, 3.74, 7.35°Brix, 87.06%T, and 0.44% MAE for soursop juice yield (%), pH, total soluble solids (TSS) (°Brix), clarity (%T) and titratable acidity (% malic acid equivalent, MAE), respectively. Morphologically, untreated soursop pulp presented a non-uniform spherical surface; enzyme hydrolyzed soursop exhibited ruptured and wrinkled surface; meanwhile for the different pectin obtained, untreated soursop pectin depicted porous surface and enzyme hydrolyzed soursop pectin showed whirling rough surface. Fourier-transform infrared (FTIR) confirmed the presence of similar chemical group stretching and vibrations in commercial pectin and soursop pectin. CONCLUSION: Under the optimum conditions, the numerical predictions were similar to the experimental data obtained, thus confirming the validity of the models. Application of enzyme treatment caused the breakdown of pectin structure as illustrated by scanning electron microscopy (SEM) and FTIR analyses. Supporting information may be found in the online version of this article.

Isolation and Characterisation of Value Added Product from Underutilised Part of Banana

“…Gelling properties of pectin are determined by their degree of esterification and lies in the range of 60 to 90% (21) In previous studies, it was reported that the degree of esterification is affected by temperature (22) . Depending on the degree of proportion, pectin can be divided into two parts-rapid settings (DE> 72%), slow setting (DE,58-65%) (23)…”

Preparation of W/O/W Lactiplantibacillus plantarumL3 microcapsules using modified low methoxy pectin as wall materials and their application in simulated yoghurt fermentation systems

“…Pectin has a wide application prospect in the field of food because of its high abundance, the existence of functional components and excellent biocompatibility (Roy et al 2023). The application of enzyme treatment causes the removal of pectin methyl ester, leading to the breakdown of galacturonic acid bonds in pectin molecules (Makebe et al 2020). Figure 1 (a) showed that the pectin DE decreased rapidly for the first 60 min, which might be explained by the higher content of galacturonic acid in HMP at the initial stage of the reaction (Johansson et al 2002).…”

“…The application of enzyme treatment causes the removal of pectin methyl ester, leading to the breakdown of galacturonic acid bonds in pectin molecules (Makebe et al . 2020). Figure 1(a) showed that the pectin DE decreased rapidly for the first 60 min, which might be explained by the higher content of galacturonic acid in HMP at the initial stage of the reaction (Johansson et al .…”

“…The absorption peak at 1741.21 cm À1 was the stretching vibration of the C=O bond in the ester group (-COOR). One study showed the assignment of C=O stretching vibration of the methyl-esterified carboxyl groups of bands at 1749.0 cm À1 for commercial pectin and soursop pectin (Makebe et al 2020). The absorption peak at 1622.31 cm À1 was the asymmetric stretching vibration of carboxylate (-COO-) peak ester bond in pectin galacturonic acid.…”

Improved microfiltration of Opuntia cactus cladode juice by enzymatic treatment

“…(2018) indicated the improved contents and capacities of bioactive compounds in chokeberry juice with the addition of pectinolytic enzymes. Enzymatic liquefaction of other fruit juices such as apple and umbu (de Oliveira et al., 2018), blueberry (Siddiq et al., 2018), and soursop (Makebe et al., 2020) has also been reported.…”