submission to thermal stress cycles promoted a 55.5% reduction in viscosity at the lowest shear rate studied (Table 3). Such a behavior is possibly associated with physical–chemical interactions between the constituents of the formulations, which are infl uenced by the concentrations of each component. All samples presented characteristics of a pseudoplastic fluid (Figure 5), since there was reduction of viscosity when the shear rate was increased. This phenomenon is confirmed by the values obtained for the flow behavior indices n (Table 3), where all samples presented values below 1 (n 1) (33). Pseudoplastic behavior is a desir- able rheological property in cosmetic formulations because it improves their ap- plicability and spreadability (34). The viscosity data suggest that TM could be used as a substitute thickening agent for xanthan gum in cosmetic formulations. Such a property is quite interesting considering that xanthan gum is a relatively expensive product and TM could be produced in large quantities at relatively lower costs. The use of TM in cosmetic products would add value to this mucilage and could strengthen the production chain of Colocasia esculenta in devel- oping countries where it has been cultivated. CONCLUSIONS The mucilage of rhizomes of Colocasia esculenta (L.) Schott rose variety has semicrystalline characteristics and relatively high thermal stability, considering the cosmetics and food industry standards. It has in its composition clusters of proteins and carbohydrates, which may be associated with the presence of arabinogalactan, that are responsible for the good Figure 5. Rheological behavior of the emulsion samples in the stability study for 24 h, iced (I) and defrost (D). F1: control formulation using 0.3% xanthan gum, *F2: 0.1% TM, *F3: 0.3% TM, and *F4: 0.5% TM. TARO MUCILAGE IN COSMETIC FORMULATIONS 289

capacity and EA, besides stabilizing emulsions. TM contributes to obtaining stable cosmetic emulsions, similar to emulsions obtained using xanthan gum. All samples presented pseu- doplasticity, with fl ow indexes lower than 1, a desirable characteristic in cosmetic formula- tions, as it improves their applicability. These results appear as important responses to the potential use of TM as an emulsifying agent for cosmetic emulsions, since the scenario has a good market forecast for plant-derived cosmetics. With high acceptance rates due to their nontoxicity and nonirritating characteristics, natural mucilages are gaining attention from the cosmetics sector, being an alternative to conventional biopolymers. ACKNOWLEDGMENTS The authors are grateful to Universidade Tecnológica Federal do Paraná (Central Analyses of UTFPR-PB and Multi-User Center for Materials Characterization, CMCM of UTFPR- CT), Universidade Comunitária da Região de Chapecó, and Universidade do Oeste de Santa Catarina for the support in the analysis. The authors also thank the Brazilian Coorde- nação de Aperfeiçoamento de Pessoal de Nível Superior and Conselho Nacional de Desen- volvimento Científi co e Tecnológico agencies. REFERENCES (1) Y. N. Aboubakar, J. Njintang, C. M. Scher, and F. Mbofung, Physicochemical, thermal properties and microstructure of six varieties of taro (Colocasia esculenta L. Schott) fl ours and starches, J. Food Eng., 86, 294–305 (2008). (2) L. A. Andrade, C. A. Nunes, and J. Pereira, Relationship between the chemical components of taro rhizome mucilage and its emulsifying property, Food Chem. Oxford, 178(1), 331–338 (2015). (3) D. T. Banjaw, Review of taro (Colocasia esculenta) genetics and breeding, J. Hortic., 4(1), 1000196 (2017). (4 ) BRASIL, Ministério da Agricultura, Pecuária e Abastecimento. Secretaria de Desenvolvimento Agro- pecuário e Cooperativismo. Taro (ex-inhame) [Colocasia esculenta (L.) Schott]. In: Manual de hortaliças não-convencionais (Brasília, 2010), accessed may 26, 2017, http://www.abcsem.com.br/docs/manual_hor- talicas_web.pdf. (5) C. M. DE Castro and A. C. P. Devide, 2016. Cultivo e Propriedades de Plantas Alimentícias não Convencionais PANC (Pindamonhangaba, 2010), accessed may 26, 2017, http://www.aptaregio n al.sp.gov.br/documentos- diversos/1706-cartilha-cultivo-e-propriedades-d-plantas-alimenticias-nao-convencionais-panc/fi le.html. (6) E. F. Donkor, D. Nyadanu, R. Akromah, and K. Osei, Genotype-by- environment interaction and stabil- ity of taro [Colocasia esculenta (L.) Schott.] genotypes for yield and yield componen ts , Ecol. Genet. Genom., 17, 100070 (2020). (7) G. K. Jani, D. P. Shah, V. D. Prajapati, V. C. Jain, Gums and mucilages: versatile excipients for phar- maceutical formulations, Asian J. Pharm. Sci., 4(5), 308–322 (2009). (8) U. M. Deo g ade, V. N. Deshmukh, and D. M. Sakarkar, Natural gums and mucilage’s in NDDS: ap- plications and recent approaches. Int. J. Pharm Tech Res., 4, 799–814 (2012). (9) L. A. Andrad e , N. A. Barbosa, and J. Pereira, Extraction and properties of starches from the non-tradi- tional vegetables Yam and Taro, Polímeros, 27(2), 151–157 (2017). (10) A. Mishra, A . Yadav, S. Pal, and A. Singh, Biodegradable graft copolymers of fenugreek mucilage and polyacrylamide: a renewable reservoir to biomaterials, Carbohydr. Polym., 65, 58–63 (2006). (11) C. A. Alalor, J. A. Avbunudiogba, and K. Augustine, Isolation and characterization of mucilage ob- tained from Colocasia esculenta. Int. J. Pharm. Biol. Sci., 4(1), 25–29 (2014). (12) N. Y. Njintang, T. Boudjeko, L. N. Tatsadjieu, E. Nguema-Ona, J. Scher, and C. M. F. Mbofung. Com- positional, spectroscopic and rheological analyses of mucilage isolated from taro (Colocasia esculenta L. Schott) corms. J. Food Sci. Technol. London, 48(5), 900–907 (2011). (13) L. A. Andrade, Caracterização da mucilagem do taro (Colocasia esculenta) quanto ao poder emulsifi cante (Master’s Thesis, Universidade Federal de Lavras, Lavras, MG, 2013). JOURNAL OF COSMETIC SCIENCE 290