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Tack is used to identify the quality of the formulation after application to a substrate and relates to what the consumer may feel in regards to stickiness either after application or after eating oily foods that may cause the formulation to degrade, in turn causing the formulation to run off or have a tacky feel. This method uses the Texture Analyzer and calculates the removal force of a 1/2” stainless steel ball probe after contact with the dried formulation [54]. The maximum force detected is considered to be the tack. This measurement is conducted five times on a sample and averaged in order to find the average tack force for the sample. This test can also be conducted after exposure to olive oil and saliva to determine the impact on the formulation, relating to product performance after eating or after the consumer licks her lips. Long-wear lipsticks that have a wide stick have a higher tack force as a result of higher evaporation of the volatile solvent.