Application of colorimeter in quality detection of vegetable oil

Vegetable oil is one of the indispensable condiments in our current life. People in modern life have higher and higher requirements for quality of life. The safety and nutritional value of food is one of the most concerned issues for consumers. Many chemicals designed in the traditional way of detecting plants have a great impact on the food itself, and the measurement results are not necessarily accurate, so now scientific manufacturers start to use colorimeter, a new precision instrument for detection.

At present, there are many indicators for testing vegetable oil, such as acid value, iodine value, peroxide value, etc. However, because the chemical method is more troublesome and requires a large amount of organic solvents, it not only increases the detection cost, but also causes harm to the detector. Therefore, oil color and lustre become one of the basis of oil quality evaluation.

Vegetable oils have different colors, mainly because the oil seeds contain carotenoids, flavonoid pigments, chlorophyll, gossypol and other pigment substances, which are soluble in oils during the process of oil production. The color of oil is not only related to the color of oil seeds, but also related to processing technology and refining process. In addition, the deterioration of oil quality and rancidity of oil will also lead to the darkening of oil color.

Therefore, measuring the color of oil can understand the purity, processing technology and refining degree of oil, and can also judge whether it is deteriorated. In the national standard of vegetable oil in China, the Lovibond colorimeter method is often used to determine the color, and the corresponding indicators are formulated. However, visual comparison of oil color requires skilled experience and high quality, and the appearance of colorimeter has replaced this visual colorimetry due to the influence of environmental factors.

The relationship between color parameters and chemical indexes of heated peanut oil was studied. The results showed that the acid value and iodine value were linear with heating time and color parameters, respectively; The peroxide value increases sharply at first and then decreases slowly with the increase of heating time, which is not linear with the color parameters L *, a * and b *.

The colorimeter is not only fast, accurate and safe in measuring the color of vegetable oil, but also clear in analysis. Most color difference meters in the market now provide upper computer software that can directly connect the color difference meter with the computer, establish a color database, and provide the greatest convenience for color measurement and rating of future products.

Evaluation of noodle color by colorimeter：
Using a color difference meter to detect the color of noodles is a completely achievable and now very perfect way. We know that most of the noodles in the market are white at present. The decisive factor for the color of white noodles is flour. The color of noodles made from flour of different product brands is different.

However, the first sense for consumers to choose noodles is the color of noodles. The noodles with fresh color are more popular with consumers. Nowadays, noodle manufacturers use colorimeter to analyze the color of noodles scientifically, quickly and clearly. In the experiment, a variety of wheat samples were used to make noodles, and then the application of colorimeter in the evaluation of noodle quality and color was studied according to noodle making, sensory evaluation of noodle color, noodle color determination and wheat pink color determination.

According to the measured data and analysis results and the color difference calculation equation in photometry, the color difference instrument is used to replace the color score in sensory evaluation. Considering the simplicity of the test operation and the effect of the equation prediction, the equation is: color y=2.176+0.278 × L (boiled) – 1.515 × A (boiling) -0.07 × B (cooking) can directly evaluate the color of noodles.

The evaluation of noodle quality is not only a simple evaluation of whether noodles are delicious or not, but also the main basis for evaluating wheat grain quality and wheat flour quality, providing technical support for wheat breeding, processing and storage. At present, sensory evaluation is still the main method of noodle quality evaluation. However, the sensory evaluation of noodles has a high requirement for the evaluators, and there are many factors that affect the evaluation. The results of identification in different regions and laboratories may vary greatly.

With the development of wheat flour processing industry, consumers’ first impression of noodles is color, which directly affects people’s judgment on the quality of noodles. The color of noodles has gradually become an important sensory evaluation index. Measuring the color of noodles with a color difference meter is helpful to objectively evaluate the quality difference of noodles and reduce human error.

At present, the most commonly used method to represent color is L * a * b * color space method, where L * is the brightness of the sample color; A *, b * is the color direction,+a * is the red direction, – a * is the green direction,+b * is the yellow direction, – b * is the blue direction. It can not only be used to test the whiteness of the powdery matter wheat flour that can flow, but also can give an objective quantitative evaluation of the surface whiteness and gloss of the finished products. By integrating L *, a *, b *, it can comprehensively reflect the deviation of the surface color or internal tissue of noodles, steamed bread, bread, noodles and other foods, so as to more accurately compare the color difference between different samples.

The application of colorimeter in the evaluation of noodle color is no longer fresh food. We use this sophisticated and advanced instrument to analyze the color of flour, noodles and cooked noodles. From the taste and color, we can determine which color data of flour makes the noodles taste best. This is also the result of the promotion of the times after the production industry has entered the era of technology and digitalization.

LISUN lauched Portable Colorimeter/Chroma Meter is an innovation color measuring tool with powerful configuration to make color measurement easier and more professional; It support Bluetooth to connect with Android and ISO devices, Portable Colorimeter/Chroma Meter will take you into a new world of color management; It can be widely used to measure color value, color difference value and find similar color from color cards for printing industry, paint industry, textile industry, etc.

CD-320PRO_Portable Colorimeter/Chroma Meter

Lisun Instruments Limited was found by LISUN GROUP in 2003. LISUN quality system has been strictly certified by ISO9001:2015. As a CIE Membership, LISUN products are designed based on CIE, IEC and other international or national standards. All products passed CE certificate and authenticated by the third party lab.

Our main products are Goniophotometer, Integrating Sphere, Spectroradiometer, Surge Generator, ESD Simulator Guns, EMI Receiver, EMC Test Equipment, Electrical Safety Tester, Environmental Chamber, Temperature Chamber, Climate Chamber, Thermal Chamber, Salt Spray Test, Dust Test Chamber, Waterproof Test, RoHS Test (EDXRF), Glow Wire Test and Needle Flame Test.

Please feel free to contact us if you need any support.
Tech Dep: Service@Lisungroup.com, Cell/WhatsApp:+8615317907381
Sales Dep: Sales@Lisungroup.com, Cell/WhatsApp:+8618117273997