Optimization of Ultrasound-assisted Extraction of Pectin from Tomato Pomace Using Response Surface Methodology

Document Type : Research Article

Authors

• Mahdi Zahedi
• Zohreh Hamidi-Esfahani
• Hassan Ahmadi Gavghili

Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran.

https://doi.org/10.22067/ifstrj.v15i2.71212

Abstract

Introduction: Pectin is a structural heteropolysaccharide in the cell wall of plants and after extraction it is used as a gelling agent in food products. The main sources of pectin are apple and citrus peel, but pectin from various sources, may have unique properties. Therefore, research is ongoing to find new sources of pectin and study their properties. The conventional extracting method is performed using a solution of mineral acids, this process is time-consuming and has some disadvantages in terms of quantity and quality of extracted pectin. It is very important to look for new methods or modifications to produce pectin with high efficiency and quality. One of the new methods is ultrasonic extraction, which has been studied extensively. The aim of this study was to optimize and quantitative and qualitative evaluation of pectin extraction from tomato pomace as one of the major wastes of industries in Iran. Also Ultrasound was used as a new and effective method for extraction of pectin. Ultrasound assisted extraction (UAE) of pectin from waste tomato pomace was investigated and optimized using Box–Behnken response surface design. The individual and interactive effect of process variables (pH, temperature, extraction time and power density) on the pectin yield and purity was studied. Also, the degree of esterification, intrinsic viscosity and emulsifying properties were determined on optimized conditions.
 
Materials and methods: Tomato pomace was supplied from ATA Company located in Tehran, Iran. It was dried at 60 °C for 36 hours. Then was milled and sieved by 60 mesh size screen. Fatty acids and pigments were removed from tomato pomace and again dried. The obtained powder stored at ambient condition for further uses. Ultrasonic device (Ultrasonic Technology Development Company, IRAN and 400 w, 20 KHz) with 12 mm probe and double-shell tank was used to carry out the extraction. Response surface methodology (RSM) was carried out to study the effect of pH (1.5-2.5), temperature (60-90℃), extraction time (6-30 minutes), and power density (0.15-0.3 W/ml) as input variables on the yield and galacturonic acid (GalA) content as the output (responses). GalA content was determined by colorimetric method (titration), using the 3, 5- dimethylphenol as reagent and D-galacturonic acid as standard. To determine the degree of esterification, titration method was used. The intrinsic viscosity of pectin was determined by applying a capillary viscosimeter (Cannon Instruments Co., No. 150, Cannon-Fenske, Germany; k = 0.04137 mm2/s2). Emulsifying properties of pectin extracted at the optimal point were investigated at three levels of pectin concentration %0.25,% 0.5 and %1.
 
Results and discussion: The experimental data obtained were analyzed by analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis both for pectin yield and GalA content. The models developed from the experimental design were predictive and good fit with the experimental data with high coefficient of determination (R2) value. Pectin yield and GalA content were more influenced by temperature. The highest extraction yield (10.5%) and galacturonic acid content (65%) was obtained at pH of 2, temperature of 86℃, time of 30 min, and power density of 0.3 W/ml, while in the conventional extraction method with the same extraction conditions, extraction yield of 4.5% and galactoronic acid content of 55% was obtained. According to results of this experiment, it can be concluded that main advantage of UAE is considerable shortening of extraction time with enhancement of pectin purity. Under optimal conditions, pectin with a degree of esterification 76% and intrinsic viscosity of 2.6 dl/g was obtained. The highest emulsifying activity (87.5%) was obtained at %1 concentration. By holding the emulsion at a temperature of 4°C and 23°C, the emulsion stability was significant (99%) at the concentration of %0.25 over a period of 30 days. These results showed that tomato pomace could be used as a good source of low cost pectin.

Keywords

• Pectin extraction
• Tomato pomace
• Ultrasound
• Emulsifying activity

References

1. Anese, M., Mirolo, G., Beraldo, P., Lippe, G. (2013). Effect of ultrasound treatments of tomato pulp on microstructure and lycopene in vitro bioaccessibility. Food Chemistry, 136, 458-63.
2. Assoi, S., Konan, K., Walker, L.T., Holser, R., Agbo, G.N., Dodo, H., Wicker, L. (2014). Functionality and yield of pectin extracted from Palmyra palm (Borassus aethiopum Mart) fruit. LWT - Food Science and Technology, 58, 214-221.
3. Baississe, S., Ghannem, H., Fahloul, D., Lekbir, A. (2010). Comparison of structure and emulsifying activity of pectin extracted from apple pomace and apricot pulp. World Journal of Dairy Food and Science, 5, 79-84.
4. Chan, S.Y., Choo, W.S. (2013). Effect of extraction conditions on the yield and chemical properties of pectin from cocoa husks. Food Chemistry, 141, 3752-8.
5. Dalev, P.G., Simeonova, L.S. (1995). Emulsifying properties of protein–pectin complexes and their use in oil-containing foodstuffs. Journal of Science & Food Agriculture, 68, 203-206.
6. Ele-Ekouna, J.P., Pau-Roblot, C., Courtois, B., Courtois, J. (2011). Chemical characterization of pectin from green tea (Camellia sinensis). Carbohydrate Polymer, 83, 1232-9.
7. Gnanasambandam, R., Proctor, A. (1999). Preparation of soy hull pectin. Food Chemistry, 65, 461-7.
8. Grassino, A.N., Halambek, J., Djaković, S., Rimac Brnčić, S., Dent, M., Grabarić, Z. ( 2016). Utilization of tomato peel waste from canning factory as a potential source for pectin production and application as tin corrosion inhibitor. Food Hydrocolloids, 52, 265-74.
9. Happi Emaga, T., Ronkart, S.N., Robert, C., Wathelet, B., Paquot, M. (2008). Characterisation of pectins extracted from banana peels (Musa AAA) under different conditions using an experimental design. Food Chem, 108, 63-71.
10. Hosseini, S.S., Khodaiyan, F., Yarmand, M.S. (2016). Optimization of microwave assisted extraction of pectin from sour orange peel and its physicochemical properties. Carbohydrate Polymers, 140, 59-65.
11. Iglesias, M.T., Lozano, J.E. (2004). Extraction and characterization of sunflower pectin. Journal of Food Engineering, 62, 215-23.
12. Kar, F., Arslan, N. (1999). Effect of temperature and concentration on viscosity of orange peel pectin solutions and intrinsic viscosity–molecular weight relationship. Carbohydrate Polymers. 40, 277-84.
13. Leroux, J., Langendorff, V., Schick, G., Vaishnav, V., Mazoyer, J. (2003). Emulsion stabilizing properties of pectin. Food Hydrocolloids, 17,455-462.
14. Liu, L., Cao, J., Huang, J., Cai, Y., Yao, J. (2010). Extraction of pectins with different degrees of esterification from mulberry branch bark. Bioresource Technology, 101, 3268-73.
15. Li, X., Liu, Z., Lu, B. (2014). Ultrasonic-assisted extraction of pectin from chaenomeles. Journal of Central South University, 21, 4115-20.
16. Maran, J.P., Priya, B. (2015). Ultrasound-assisted extraction of pectin from sisal waste. Carbohydrate Polymers, 115, 732-8.
17. Ma, S., Yu, S., Zheng, X., Wang, X., Bao, Q. Guo, X. (2013). Extraction, characterization and spontaneous emulsifying properties of pectin from sugar beet pulp. Carbohydrate Polymers, 98, 750-753.
18. Minjares-Fuentes, R., Femenia, A., Garau, M.C., Meza-Velazquez, J.A., Simal, S., Rossello, C. (2014). Ultrasound-assisted extraction of pectins from grape pomace using citric acid: A response surface methodology approach. Carbohydrate Polymers, 106, 179-89.
19. Moorthy, I.G., Maran, J.P., Surya, S.M., Naganyashree, S., Shivamathi, C.S. (2015). Response surface optimization of ultrasound assisted extraction of pectin from pomegranate peel. Journal of Biological Macromolecules, 72, 1323-8.
20. Pagan, J, Ibarz, A. (1999) Extraction and rheological properties of pectin from fresh peach pomace. Journal of Food Engineering., 39, 193-201.
21. Prakash Maran, J., Sivakumar, V., Thirugnanasambandham, K., Sridhar, R. (2014). Microwave assisted extraction of pectin from waste Citrullus lanatus fruit rinds. Carbohydrate Polymers. 101, 786-91.
22. Ptitchkina, N.M., Danilova, I.A., Doxastakis, G., Kasapis, S., Morris, E.R. (1994). Pumpkin pectin: gel formation at unusually low concentration. Carbohydrate Polymers. 23, 265-73.
23. Santos, J.D.G., Espeleta, AF., Branco, A., de Assis, S.A. (2013). Aqueous extraction of pectin from sisal waste. Carbohydrate Polymers. 92, 1997-2001.
24. Scott, R.W. (1979). Colorimetric determination of hexuronic acids in plant materials. Analytical Chemistry, 51, 936-41.
25. Supardan, M.D., Fuadi, A., Alam, P.N., Arpi, N. (2011). Solvent extraction of ginger oleoresin using ultrasound. Makara, Sains. 15, 163-7.
26. Van Buren, J.P. (1991). CHAPTER 1 - Function of Pectin in Plant Tissue Structure and Firmness A2, in: Walter, Reginald H. The Chemistry and Technology of Pectin, Academic Press., San Diego, pp 1-22.
27. Wang, W., Ma, X., Xu, Y., Cao, Y., Jiang, Z., Ding, T. (2015). Ultrasound-assisted heating extraction of pectin from grapefruit peel: Optimization and comparison with the conventional method. Food Chem., 178,106-14.
28. Willats, W.G.T., Knox, J.P, Mikkelsen J.D. (2006). Pectin: new insights into an old polymer are starting to gel. Trends in Food Science & Technology, 17, 97-104.
29. Xu, Y., Zhang, L., Bailina, Y., Ge, Z., Ding, T., Ye, X., et al. (2014). Effects of ultrasound and/or heating on the extraction of pectin from grapefruit peel. Journal of Food Engineering, 126, 72-81.
30. Yapo, B.M., Robert, C., Etienne, I., Wathelet, B., Paquot, M. (2007). Effect of extraction conditions on the yield, purity and surface properties of sugar beet pulp pectin extracts. Food Chem., 100, 1356-64.