Microencapsulation of Purple-Fleshed Sweet Potato Anthocyanins with Chitosan-Sodium Tripolyphosphate by Using Emulsification-Crosslinking Technique


  • Umi Laila Research Unit for Natural Product Technology, Indonesian Institute of Sciences, Jalan Jogja-Wonosari KM 31,5, Desa Gading Kecamatan Playen, Kabupaten Gunungkidul, Yogyakarta 55861
  • Rochmadi Rochmadi Department of Chemical Engineering, Universitas Gadjah Mada, Yogyakarta 55281
  • Sri Pudjiraharti Development Unit for Clean Technology, Indonesian Institute of Sciences, Gedung 50 ?? Kampus LIPI, Jalan Cisitu Sangkuriang, Bandung 40135




anthocyanins, chitosan, crosslinking, emulsification, microencapsulation, parameters


Anthocyanins extracted from purple-fleshed sweet potato were encapsulated using emulsification-crosslinking technique with chitosan acted as polymer and sodium tripolyphosphate as cross-linker. The parameters influencing microencapsulation were investigated i.e. stirring intensity and polymer concentration, pH of polymer and crosslinker solution, and also ratio of anthocyanins extract (core) to polymer concentration by characterizing the properties of obtained microcapsules. Stirring intensity of 1600 rpm achieved microcapsules with smaller mean diameter, narrower particle size distribution, and greater encapsulation efficiency than that of 1200 rpm for each similar polymer concentration. The research revealed that pH of 3.0 gave the greatest encapsulation efficiency and antioxidant activity of microcapsules. However, the different of mean diameter and particle size distribution of microcapsules for all of pH solution variation was not significant. Ratio of anthocyanins extract to polymer concentration 75% (w/w) possessed the greatest encapsulation efficiency, the biggest mean diameter and the widest particle size distribution between all of ratio variation. Meanwhile, ratio of 150% was selected for further analysis (microstructure and FT-IR) because it gave narrower particle size distribution and smaller mean diameter with its encapsulation efficiency was only little different from others ratio. Microstructure analysis by SEM revealed sphere and irregular microparticles. FT-IR analysis revealed that that there was bonding and interaction among anthocyanin, chitosan, and tripolyphosphate ion.


Betz, M., Steiner, B., Schantz, M., Oidtmann, Mader, K., Richling, E. & Kulozik, U., Antioxidant Capacity of Bilberry Extract Microencapsulated in Whey Protein Hydrogels, Food Res. Int., 47, pp. 51-57, 2012.

Al-farsi, M., Alasavar, C., & Morris, A., Comparison of Antioxidant Activity, Anthocyanins, Carotenoids, and Phenolic of Three Native Fresh and Sun Dried Date (Phoenix Dactylferon L) Varieties Grown in Oman, J. Agric. Food. Chem., 53(19), pp. 7592-7599, 2005.

Ghosh, D., & Konishi T., Anthocyanins and Anthocyaian-Rich Extracts: Role in Diabetes and Eye Function, Asia Pac. J. Clin. Nutr., 16(2), pp. 200-208, 2007.

Roobha, J.J., Saravanakumar, M., Aravindan, K.M. & P.S, Devi., The Effect of Light, Temperature, pH on Stability of Anthocyanin Pigments in Musa Circuminata bract., Res. Plant Bio., 1(5), pp. 5-12, 2011.

Faria, A., Fernandes, I., Mateus, N. & Calhau, C., Bioavailability of Anthocyanins, Nat. Prod., pp. 2465-2487, 2013.

Gould, K., Davies, K.M. & Winefield, C., Anthocyanins: Biosynthesis, Funtions, and Applications, Springer Science & Business Media, 2008.

Bakowska-Barczak, A., Acylated Anthocyanins as Stable, Natural, Food Colorants - A Review, Polish Journal of Food and Nutrition Sciences, 14/55(2), pp. 107-116, 2005.

Patras, A., Brunton, N.P., O'Donnell, C. & Tiwari, B.K., Effect of Thermal Processing on Anthocyanin Stability in Foods: Mechanisms and Kinetics of Degradation, Trends Foods Sci. Technol., 21(1), pp. 3-11, 2010.

Betchtold, T. & Mussak, R., Handbook of Natural Colorants. John Wiley and Sons, 2009.

Parisi, O.I., Puoci, F. & Restuccia D., Polyphenols and Their Formulations: Different Strategies to Overcome the Drawbacks Associated with Their Poor Stability and Bioavailability, Polyphenols in Hum. Health and Dis., 1, pp. 29-45, 2011.

Xu, J., Su, X., Lim, S., Griffin, J., Carey, E., Katz, B., Tomich, J., Smith, J. & Wang W., Characterisation and Stability of Anthocyanins in Purple-Fleshed Sweet Potato P40, Food Chem, 186, pp. 90-96, 2015.

Li,Jie., Li, Xiao-Ding., Zhang,Yun., Zheng, Zheng-Dong., Qu, Zhi-Ya., Liu, Meng., ZhuS, hao-hua., Liu, Shuo,. Wang, Meng. & Qu, Lu., Identification and Thermal Stability of Purple-Fleshed Sweet Potato Anthocyanins in Aqueous Solutions with Various pH Values and Fruit Juices, Food Chem., 136(3-4), pp. 1429-1434, 2013.

Saputra, K.A., Angela, A., Surya, R., Gifsan, Y. & Priskila, Application of Chitosan as Preservatives on Organic Fruits, Asian J. Food Agro-Ind., Special Issue, pp. S264-S270, 2009.

Wang, L.Y., Gu, Y.H., Zhou, Q.Z., Ma, G.H., Wan, Y.H. & Su, Z.G., Preparation and Characterization of Uniform-Sized Chitosan Microspheres Containing Insulin by Membrane Emulsification and A Two-Step Solidification Process, Colloids Surf., B, 50, pp. 126-135, 2006.

Ye, M., Kim, S. & Park, K., Issues in Long-term Protein Delivery using Biodegradable Microparticles, J. Controlled Release, 146(2), pp. 241-260, 2010.

Giusti, M. & Wrolstad, R.E., Characterization and Measurement of Anthocyanins by UV-Visible Spectroscopy, Current Protocols in Food Analytical Chemistry, pp. F1.2.1-F1.2.13., 2001.

Brand-Williams, W., Cuvelier, M.E. & Berst, C., Use of a Free Radical Method to Evaluate Antioxidant Activity, Lebensm.-Wiss.u.-Technol, 28, pp. 25-30, 1995.

Wang, W., Jung, J. & Zhao, Y., Chitosan-cellulose Nanocrystal Microencapsulation to Improve Encapsulation Efficiency and Stability of Entrapped Fruit Anthocyanins, Carbohydr. Polym., 157, pp. 1246-1253, 2017.

Servat-Medina, L, Gonzalez-Gomez, A., Reyes-Ortega, F., Sousa, I.M., Queiroz, N.D.C.A., Zago, P.M., Jorge, M.P., Monteiro, K.M., de Carvalho, J.E., San Roman, J. & Foglio, M.A.., Chitosan-tripolyphosphate Nanoparticles as Arrabidaea Chica Standardized Extract Carrier: Synthesis, Characterization, Biocompatibility, and Antiulcerogenic Activity, Int. J. Nanomedicine, 10(1), pp. 3897-3909, 2015.

Shu, X.Z. & Zhu, K.J., The Influence of Multivalent Phosphate Structure on the Properties of Ionically Cross-linked Chitosan Films for Contolled Drug Release, European J. Pharm. and Biopharm., 54(2), pp. 235-243, 2002.

Martins, A.F., de Oliveira, D.M., Pereira, A.G.B., Rubira, A.F. & Muniz, E.C., Chitosan/TPP Microparticles Obtained by Microemulsion Method Applied in Controlled Release of Heparin, Int. J. Bio. Macromolecules, 51, pp. 1127-1133, 2012.