Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Dec;29(8):779-788.
doi: 10.1177/10820132221117457. Epub 2022 Jul 29.

Process optimisation for enzymatic clarification of indigenous wild watermelon (Citrullus lanatus) juice

Moselo Maureen Mamabolo  1 , Frederick Tawi Tabit  1
Affiliations

Process optimisation for enzymatic clarification of indigenous wild watermelon (Citrullus lanatus) juice

Moselo Maureen Mamabolo et al. Food Sci Technol Int. 2023 Dec.

Abstract

A fundamental step in improving the quality and consumer acceptability of wild watermelon (Citrullus lanatus) is the process of juice clarification. The aim of this research was to investigate the physicochemical properties of crude wild watermelon (Citrullus lanatus) juice and to optimise the processing conditions, incubation time, incubation temperature and enzyme concentration for the enzymatic clarification of the crude juice. Crude wild watermelon juice samples were treated with pectinase enzyme in different concentrations (0.05 to 0.15 w/w%), at different incubation temperatures (30-50 oC) and for different incubation durations (60-180 min). The effects of the different treatments on turbidity, clarity, viscosity, lightness, and brix were determined. The response models adequately predicted turbidity, clarity, and viscosity at R2 > 0.5, but not lightness considering that R2 < 0.5. The model was statistically significant in predicting turbidity (R2 = 0.86), clarity (R2 = 0.81), viscosity (R2 = 0.97) and brix (R2 = 0.94) - but not lightness (R2 = 0.24) at p < 0.05. The enzyme concentration did not significantly affect turbidity, clarity, and lightness, but it did significantly affect brix positively (p < 0.05). Response surface methodology software was used to determine optimal clarification conditions. In conclusion, the optimum conditions for crude watermelon juice clarification were 0.15 w/w% enzyme concentration, 60 min incubation time and 60 oC incubation temperature. The optimum output parameters were 14.18 NTU for turbidity, 0.04 Abs for clarity, 52.30 L* value for lightness, 1.96 cps for viscosity and 3.08% for Brix.

Keywords: Wild watermelon; clarification; crude juice; optimisation; temperature.

PubMed Disclaimer

Conflict of interest statement

DECLARATION OF CONFLICTING INTERESTSThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
3d plot for turbidity of wild watermelon juice as a function of enzyme concentration (w/w%) and incubation time at 30 °C.
Figure 2.
Figure 2.
3d plot for clarity at 660 nm of wild watermelon juice as a function of enzyme concentration (w/w%) and incubation time at 30 °C.
Figure 3.
Figure 3.
3d plot for the viscosity of wild watermelon juice as a function of enzyme concentration (w/w%) and incubation time at 30 °C.
Figure 4.
Figure 4.
3d plot for L* value of wild watermelon juice as a function of enzyme concentration (w/w%) and incubation time at 30 °C.
Figure 5.
Figure 5.
3d plot for brix of wild watermelon juice as a function of enzyme concentration (w/w%) and incubation time at 30 °C.
Figure 6.
Figure 6.
Contour plots for optimum conditions of turbidity, clarity, L* value, viscosity and brix as a function of enzyme concentration, incubation time and incubation temperature at 30 °C
See this image and copyright information in PMC

References

    1. Abdullah AGW, Sullaiman NM, Auroua MK, et al. (2007) Response surface optimization of conditions for clarification of carambola fruit juice using a commercial enzyme. Journal of Food Engineering 81: 65–71.
    1. Aghajanzadeh S, Ziaiifar AM, Kashaninejad M, et al. (2016) Thermal inactivation kinetic of pectin methylesterase and cloud stability in sour orange juice. Journal of Food Engineering 185: 72–77.
    1. Akhtar M, Chan P, Safriani N, et al. (2011) Concentration of apple juice using spinning disc reactor technology. Journal of Food Processing and Technology 2: 108.
    1. Arsad P, Sukor R, Wan Ibadullah WZ, et al. (2015) Effects of enzymatic treatment on physiochemical properties of sugar palm fruit juice. International Journal on Advanced Science Engineering Information Technology 5(5): 308–312.
    1. Bender C, Killermann KV, Rehmann D, et al. (2016) Effect of mash enzyme and heat treatments on the cellular antioxidant activity of blackcurrant (Ribes nigrum), raspberry (Rubus idaus), and blueberry (Vaccinium myrtillus) juices. Journal of Food 15(2): 277–283.

LinkOut - more resources