Affiliations: Department of Food Science and Nutrition, Queen Elizabeth College (University of London), Campden Hill Road, London W8 7 AH, U.K.
Note: [*] Now at Mars Ltd., c/o Dornay Foods, Hansa Rd., Kings Lynn, PE 30 4JE, Norfolk, U.K.
Abstract: The force developed during stickiness measurements with an Instron machine has been studied at several crosshead speeds using a fast response (u.v.) recorder. In one series of tests the steel plate attached to the underside of the crosshead was pre-wetted with human saliva. Comparison of these data with data obtained previously using a standard, slow response, recorder indicates that in the u.v. recorder studies the maximum force increased with increasing crosshead speed; in the slow recorder studies the reverse was observed. Stress relaxation, cavitation effects and recorder response time may affect the maximum force registered, the last two named factors becoming particularly active at high crosshead speeds. Panelists’ evaluations of stickiness in the mouth, or with a finger or spoon, and u.v. recorder data did not follow Steven’s power relationship. It is suggested that panelists’ evaluations of stickiness by these three methods involves a mechanical situation resembling that at high crosshead speeds during instrumental evaluation with a slow response recorder. The proteins in human saliva may reduce cavitation during panelists’ evaluation of stickiness in the mouth.
DOI: 10.3233/BIR-1975-12510
Journal: Biorheology, vol. 12, no. 5, pp. 317-322, 1975
