A consistometer is a device for measuring physical consistency of a substance. It is most often used for foods such as ketchup and other thick fluid or semi-fluids.
Consistency is typically measured in terms of rate of flow, as opposed to viscosity which is measured in regards to force within units like poise. Consitometry readings can roughly correspond with viscosity measurements, but some substances such as carob flour have little to no effect on consistometer flow but can increase apparent viscosity.[1] People's sensory perception of a food seems to track more with the consistency than the viscosity.[1] Using a consitometer is also useful on non-homogeneous substances that would give poor readings with a viscometer.[1]
One of the most common types is the Bostwick consistometer which was invented by bacteriologist Elmer Patton Bostwick (1893-1958).[2][3] This device consists of a rectangular container with two sections: one of a set volume and the other at a slight decline with centimeter measurements along the bottom.[2] Dividing the two sections is a sluice gate that can be sprung quickly open, allowing the substance to flow under its own weight.[2] The distance traveled is noted at a specific time, typically thirty seconds, and compared to known samples.[1] A Bostwick consistometer is relatively easy to use in remote locations without electricity and is much cheaper than a viscometer.[1]
Another type of device is the Adams consistometer. This requires a larger sample than the Bostick does, of around a half liter as opposed to around 100 mL.[1]
References
edit- ^ a b c d e f Mouquet, Claire; Greffeuille, Valerie; Treche, Serge (2006). "Characterization of the consistency of gruels consumed by infants in developing countries: assessment of the Bostwick consistometer and comparison with viscosity measurements and sensory perception". International Journal of Food Sciences and Nutrition. 57 (7–8): 459–469. doi:10.1080/09637480600931618. ISSN 1465-3478. OCLC 110455362. PMID 17162325. Retrieved 14 January 2024.
- ^ a b c USA Expired - Lifetime US2295710A, Elmer Patton Bostwick, "Consistometer", issued 1942-09-15
- ^ "Microscope". National Museum of American History. Washington, DC. Retrieved 9 January 2024.