As described in Section 6 of ASTM D1209, there are 2 criteria to validate a APHA/Pt-Co 500 standard: Continue reading
FAQ: “We take the results from the Didymium Filter Test on our HunterLab ColorQuest XT and plot them in an SPC chart over time to look at trends. We are seeing the 430 and 570 nm filters slowly decrease. Can you help us understand what may be occurring?” Continue reading
FAQ:”A client is asking me to measure something they call “Molten Color’. Do you have any information on this? Do Hunterlab instrument have a function for this color?” Continue reading
HunterLab diffuse sphere instruments are often used to measure liquid samples, especially clear liquids. The liquid fragrance shown above is one such example of a clear liquid. The fragrances is so clear that is resembles water.
Fragrances such as this are often added to cleaning supplies, air fresheners, or other consumer products. One of the problems that this type of sample can experience is that the chemistry of the liquid fragrance solution can deteriorate and the solution will start to visually yellow. This is often a concern for manufactures because if the liquid fragrance yellows it cannot be added to the end product.
HunterLab sphere instruments can measure the transmitted color of the liquid and report the yellowness index. The liquid fragrance should be measured in a 20mm path length cell. Since the sample is very clear, near water in color, this slightly larger path length allows for the light to pass through more of the sample. This measurement method ensures that smaller differences can be measured between samples.
With the proper instrument and the appropriate accessories from HunterLab, very clear liquid samples can be accurately and repeatedly measured for color consistency.
important parameters. Hot peppers, used as relishes, pickled or ground into a fine powder for use as spices, derive their pungency from the compound capsaicin (8-methyl-N-vanillyl-6-enamide), a substance characterized by acrid and burning taste, that is located in the internal partitions of the fruit. First isolated in 1876, capsaicin stimulates gastric secretions and, if used in excess, causes inflammation. It is a tasteless, odorless white crystalline substance. Its level varies widely in capsicum peppers, from less than 0.05% in the mildly pungent types to as high as 1.3% in the hottest chilies. The pungency level is usually represented in Scoville heat values. Pungency levels vary in the same variety, by geographical region, and in maturity levels. Volatile oil content is low in all capscicums. The pigment responsible for the color in paprikas is capxanthin, a carotenoid. Other carotenoids present are capsorubin, zeaxanthin, lutein, kryptoxanthin and alpha and beta-carotene. Continue reading
HunterLab manufactures, directional 45/0 instruments and also diffuse sphere instruments, with diffuse/8˚ geometry. The UltraScan PRO, UltraScan VIS, ColorQuest XE, and ColorQuest XT are all bench top sphere instruments available from HunterLab. Continue reading
FAQ: “Do you sell a depolarizer for my HunterLab sphere instrument? On occasion we test polarized samples and there is definitely a dependence on the orientation of the lens. I was wondering if adding a depolarizer would eliminate this phenomenon?”