Abstract: A method is provided for determining a physical property of a malt beverage sample. The method includes measuring a refractive index of the malt beverage sample. The method further includes determining a temperature-compensated measured refractive index by temperature correcting the measured refractive index relative to a predetermined reference temperature. The temperature correcting is specific to the total dissolved solids of the malt beverage sample. The method also includes converting the temperature-compensated measured refractive index to a unit of measurement. The unit of measurement relates to a physical property of the malt beverage sample. Apparatus are also provided.

Abstract: A flow-through sensing apparatus includes a flow-head and a sensor that are configured to be selectively coupled through use of a quick-disconnect mechanical coupling. When the sensor is coupled with the flow-head, the sensor cooperates with the flow-head to at least partially define a sensing chamber. The sensor is configured to determine a process parameter, such as refractive index, regarding a substance in the sensing chamber.

Abstract: An illuminator for use in a refractometer having a body housing, a sample cover assembly, a prism assembly and measuring assembly for measuring the composition and density of a substance. The illuminator includes a light source, a power source for operating the light source and an operating means for selectively activating the light source. The illuminator is located in the refractometer housing such that the light source is in a position on or about the prism assembly to illuminate a fluid substance to be measured. Light from the light source is introduced at a grazing incidence to a measuring surface of the prism. Phosphorescent material in the sample cover provides reticle illumination.

Abstract: According to the present invention, there is provided an optical sensor capable of detecting, identifying or measuring a property of a solid, liquid or gas which is in contact with its measuring surface. The preferred sensor comprises an optically transparent sensing element with at least one surface, an optical energy source, means for conducting optical energy from the source to the sensing element at a specific, precisely determined angle and a photodetector. The measuring surface of the sensing element forms an interface with the substance to be measured. Optical energy is partially reflected from the interface formed at the planar surface of the transparent element toward the photodetector. It has been discovered that the resulting signal from the photodetector is proportional to the refractive index of the medium covering the outer surface of the transparent element.