JOURNAL OF COSMETIC SCIENCE 154 also generated a signifi cant amount of standard rheology data to better appreciate trends in Lissajous profi les, as well as to characterize the formulations with rheological parameters that more closely correspond to the initial tactile and at-rest properties of the formula- tion. Overall, our fi ndings demonstrate that temperature, electrolyte, oscillatory shear rate, and the tribology/surface chemistry of the rheometer probes all impact the meaning of the data. Rough parallel plate surfaces challenge the integrity of the microstructure, while smooth data tend to better correlate with characteristics like slip. In addition to the complex rheology assessment, we also conducted TPA measurements to provide an over- all characterization of key textural parameters of the formulation itself, such as fi rmness, cohesiveness, compressibility, resilience, etc. In several cases, comparison of these discrete attributes with results from linear and nonlinear rheology tests showed good correlation. Finally, sensorial analysis by an expert panel provided demonstrable discrimination between the distinct textural formulas and correlated well with several rheological parameters. ACKNOWLEDGMENTS We would like to thank the following individuals for their patience, cooperation, and important contributions to the article: Bharath Rajaram, Ph.D. (TA Instruments), Sarah Cotts, Ph.D. (TA Instruments), Professor Gareth H. McKinley, Ph.D. (MIT), William Thompson (Ashland, Inc.), Karine Deruddre (Ashland, Inc.), Nevine Issa (Ashland, Inc.), Diane Kennedy (Ashland, Inc.), Ritamarie Guerrero (Ashland, Inc.), James E. Brady, Ph.D. (Ashland, Inc.), Lexie Niemoeller, Ph.D. (TA Instruments), Alina Higham-Latshaw, Ph.D. (TA Instruments), Nathan Hesse, Ph.D. (TA Instruments), Aurelio Perez (TA Instruments), Tom Basalik (TA Instruments), David J. Moore, Ph.D. (GSK Consumer Healthcare), J.P. (writing partner and the world’s most awesome 19 year-old feline), and Donald Koelmel (TRI-Princeton). REFERENCES (1) F. J. Pilgrim and D. R. Peryam, Quartermaster Food and Container Institute for the Armed Forces (U.S.) Food Acceptance Branch, Sensory Testing Methods: A Manual. (ASTM International, 1958). (2) W. E. Craighead and C. B. Nemeroff, The Concise Corsini Encyclopedia of Psychology and Behavioral Science. (John Wiley & Sons, Hoboken, NJ, 2004), pp. 929–930. (3) S. Guest, F. McGlone, A. Hopkinson, Z. Schendel, K. Blot, and G. Essick, Perceptual and sensory- functional consequences of skin care products, J. Cosmet. Dermatol. Sci. App., 3, 66–78 (2013). (4) M. Bourne, “Food Texture,” in Encyclopedia of Agricultural, Food, and Biological Engineering, D. R. Heldman, Ed. (Marcel-Dekker, New York, 2003), pp. 352–357. (5) L. Gilbert, C. Picard, G. Savary, and M. Grisel, Impact of polymers on texture properties of cosmetic emulsions: A methodological approach, J. Sensor. Stud., 27, 392–402 (2012). (6) M. Karsheva, S. Georgieva, and S. Alexandrova, Rheological behavior of sun protection compositions during formulation, Kor. J. Chem. Eng., 29, 1806–1811 (2012). (7) T. Moravkova and P. Filip, The infl uence of thickeners on the rheological and sensory properties of cos- metic lotions, Acta Polytech. Hung., 11, 173–186 (2014). (8) M. C. Taelman, J. C. Dederen, H. Peeters, and T. F. Tadros, Skin feeling quantifi cation: An important formulators tool, 20th IFSCC Congress, Cannes, France, September 14–18 (1998). (9) E. K. Park and K. W. Song, Rheological evaluation of petroleum jelly as a base material in ointment and cream formulations: Steady shear fl ow behavior, Arch. Pharm. Res., 33, 141–50 (2010). (10) R. E. Greenaway, Psychorheology of Skin Cream, Ph.D. Thesis, University of Nottingham, Nottingham, England (2010).

LARGE AMPLITUDE OSCILLATORY SHEAR 155 (11) L. Gilbert, G. Savary, M. Grisel, and C. Picard, Predicting sensory texture properties of cosmetic emul- sions by physical measurements, Chemometr. Intell. Lab., 124, 24–31 (2013). (12) S. Ozkan, T. W. Gillece, L. Senak, and D. J. Moore, Characterization of yield stress and slip behaviour of skin/hair care gels using steady fl ow and LAOS measurements and their correlation with sensorial attributes, Int. J. Cosmet. Sci., 34, 193–201 (2012). (13) U. Yilmazer, and D. Kalyon, Slip effects in capillary and parallel disc torsional fl ows of highly fi lled suspensions, J. Rheol., 33, 1197–1212 (1989). (14) R. Buscal, Wall slip in dispersion rheology, J. Rheol., 54, 1177–1183 (2010). (15) A. Bot, I. A. van Amerongen, R. D. Groot, N. L. Hoekstra, and W. G. M. Agterof, Large deformation rheology of gelatin gels, Polym. Gels Netw., 4, 189–227 (1996). (16) R. H. Ewoldt, A. E. Hosoi, and G. H. McKinley, New measures for characterizing nonlinear viscoelastic- ity in large amplitude oscillatory shear, J. Rheol., 52, 1427–1458 (2008). (17) D. M. Kalyon, Shear viscosity and wall slip behavior of a viscoplastic hydrogel, J. Rheol., 58, 513–535 (2014). (18) R. A. Freitas Jr., Nanomedicine, Volume I: Basic Capabilities. (Landes Bioscience, Georgetown, TX, 1999). (19) D. J. Panther, and S. E. Jacob, The importance of acidifi cation in atopic eczema: An underexplored av- enue for treatment, J. Clin. Med., 5, 970–978 (2015). (20) N. Nakagawa, S. Sakai, M. Matsumoto, K. Yamada, M. Nagano, T. Yuki, Y. Sumida, and H. Uchiwa, Relationship between NMF (lactate and potassium) content and the physical properties of the stratum corneum in healthy subjects, J. Invest. Dermatol., 122, 755–763 (2004). (21) R. H. Ewoldt, P. Winter, J. Maxey, and G. H. McKinley, Large amplitude oscillatory shear of pseudo- plastic and elastoviscoplastic materials, Rheol. Acta, 49(2), 191–212 (2010). (22) R. L. McMullen, M. Gorcea, and S. Chen, “Emulsions and Their Characterization by Texture Profi le Analysis,” in Formulating Topical Applications—A Practical Guide, 1st Ed, N. Dayan, Ed. (Allured Books, Carol Stream, IL, 2013), pp. 131–153. (23) M. C. Meilgaard, C. V. Civille, and B. T. Carr, Sensory Evaluation Techniques, 4th Ed. (CRC Press, Boca Raton, FL, 2007), pp. 7–24. (24) H. P. Kavehpour and G. H. McKinley, Tribo-rheometry: From gap-dependent rheology to tribology, Tribol. Lett., 17(2), 327–335 (2004).