Optimization of enzymatic hydrolysis parameters for sapodilla fruit ( Manikara achras L.) juice extraction

Abstract

Cold pressing of sapodilla fruit pulp for juice extraction is generally difficult and yields an inferior quality of juice due to fruit tissue rigidity and its granular pulpy nature which necessitates the enzyme combination for tissue hydrolysis. A central composite design was used to optimize the sapodilla tissue hydrolysis conditions like pectinase concentration (T1 0.1%–0.2%), cellulase concentration (T2 0.05%–0.1%), incubation temperature (T3 40–50°C), and incubation period (T4 90–150 min). The responses studied were juice yield, viscosity, total soluble solid, L-value, clarity, total phenol content, and overall acceptability. Regression analysis fitted to a second-order quadratic model for each response was a significant (p < .05) function of hydrolysis. The optimized level of pectinase concentration, cellulase concentration, incubation temperature, and period was 0.125%, 0.063%, 42.50°C, and 112.20 min, respectively. The validity of the model was confirmed by the closeness of experimental values (juice yield 61.51 ± 0.50%, viscosity 2.88 ± 0.02 cps, TSS 18.66 ± 0.06 °Brix, L-value 35.94 ± 0.52, clarity (abs) 1.91 ± 0.03, TPC 1.588 ± 0.02 mg GAE/100 ml, and OA 7.23 ± 0.25) with predicted values. Practical applications Various benefits of enzymatic hydrolysis of sapodilla tissue for juice extraction have been found over conventional methods (cold and hot press). It overcomes the challenges of extractability and pressability. It also improves the functional (total phenolic content), physical (soluble solid, color, clarity, and viscosity), and sensory characteristics (overall acceptability) of juice. Higher juice yield and total phenolic content suggest that enzymatic hydrolysis of sapodilla could promote the juice industry for the production of quality juice and healthy fruit-based drinks too. The reduced processing time in enzymatic hydrolysis as compared with that in traditional method and high TSS in extracted sapodilla juice will further offer the advantages of a reduced burden on cane sugar for sweetening purpose.