Fragrance is a concentrated aromatic oil that is artificially synthesized to imitate the smell of fruits and natural fragrances, and it is an artificial fragrance. It is mostly used in the manufacture of food, daily necessities, cosmetics and cigarettes.
Food flavor refers to the fragrance of natural food, using natural and natural equivalent spices and synthetic spices to carefully blend various flavors with natural flavors. Including fruit water quality and oil quality, milk, poultry, meat, vegetables, nuts, candied fruit, emulsification and wine and other flavors, suitable for beverages, biscuits, pastries, frozen foods, candies, seasonings Foodstuffs, dairy products, canned food, wine, etc. The dosage forms of edible flavors include liquid, powder, microcapsule, slurry and so on.
Daily flavors are mainly used in shampoo, shower gel, conditioner, gel water, electric hair water, dye cream, air freshener, surface wax, incense seat, car perfume, body perfume, body spray, toilet cleaner, Disinfectant water, facial cleanser, cream, soap, washing powder, detergent, insecticide, aromatherapy liquid, aromatherapy candles, sanitary incense, incense, towels and other daily chemical industries. In addition, fine chemical industry, textile and leather industry, energy industry and other major industrial fields all need to use fragrance products.
The detection of flavor precision is one of the important indicators that need to be tested in the factory inspection report of flavor and fragrance products stipulated by the state.
The traditional hydrometer method and volumetric flask method to measure the density (relative density) of flavor and fragrance products have low detection accuracy, long time-consuming, large sample consumption, low work efficiency, human errors and quotation errors, and are not suitable for high-frequency and high-volume density testing. In this paper, the high-precision automatic density meter WMD-330 (using the U-shaped vibrating tube detection principle) produced by Shanghai Yidian Physical and Optical Instrument Co., Ltd. is used to directly detect the density of liquid flavors and fragrances, which reduces the sampling and The workload of temperature control, calculation and cleaning realizes the rapid detection of liquid density.
1. Reference standards
1. GB 5009.2-2016 National Food Safety Standard Determination of Relative Density of Food
2. GB/T 11540-2008 Determination of Relative Density of Spices
3. GB/T 4472-2011 Determination of Relative Density of Density of Chemical Products
4. Determination of Relative Density in GB/T 13531.4-2013 General Test Method for Cosmetics
Second, the use of the instrument:
1. Start up: After starting up on the same day, you need to wait for the internal temperature of the instrument to equalize before starting to measure
2. Calibration: When starting up for the first time, it is recommended to use dry air and distilled water to calibrate the instrument
3. Temperature control: The instrument adopts semiconductor refrigeration, PWM temperature control, and high-precision constant temperature control
4. Sample injection: U-shaped quartz glass tube, inject 2~3ml sample into the syringe, no air bubbles
5. Measurement: After the temperature of the sample to be measured is balanced, select the measurement mode to start the measurement
6. Data: Multi-parameter data conversion, measurement results are automatically saved, and can be exported by U disk
7. Cleaning: The air pump discharges the sample, and the U-shaped tube is cleaned with distilled water and absolute alcohol
8. Drying: The U-shaped glass tube needs to be cleaned repeatedly and decondensed with dry air
3. Measurement data
4. Product Features
1. The amount of sampling is small, only 2~3ml of sample is needed to measure a sample, saving
2. After the temperature is balanced, the measurement time is short, and it only takes about 1 minute to measure a sample, which is fast
3. The standard density can be measured directly, reducing the conversion and table look-up process, simple
4. Easy to operate, high precision, suitable for high frequency and large batch inspection, effective
5. Equipped with a variety of communication interfaces, data can be saved, exported and printed, accurate
5. Influencing factors
1. Temperature influence: the measurement temperature affects the density of the essence and the geometric size of the U-shaped tube, and precise temperature control is required
2. Effect of bubbles: If the essence injected into the U-shaped tube contains bubbles, the resonance frequency will increase and the density will decrease
3. Influence of viscosity: The viscosity of essence affects the resonance frequency of the U-shaped tube. If the viscosity is too high, it will not be able to measure accurately
4. Time influence: Some flavors are volatile, so after the temperature control of the sample injection is stable, it needs to be detected as soon as possible
6. Relevant knowledge
1. Volumetric method to measure relative density:
1) Wash the volumetric flask with lotion, distilled water, ethanol and ether in sequence, dry and cool, and weigh precisely
2) Fill the sample solution (<20°C), insert a thermometer, put it in a Water Bath at 20°C, and keep it for 20 minutes
3) Absorb the spilled liquid with a filter paper strip, cover the cap, take out the volumetric flask, dry the liquid outside the bottle with filter paper, and weigh
4) Wash the density bottle, fill it with distilled water (boil for 30 minutes and cool to below 20°C), and the rest of the operations are the same as above
5), calculation result d20=(m2-m0)/(m1-m0),
2. Matters needing attention when measuring relative density by volumetric method:
1) It is also suitable for volatile samples, and the result is accurate, but the operation is cumbersome
2) When measuring viscous samples, it is advisable to use ordinary density bottles with capillaries
3) Water and samples need to be filled with a density bottle, and there must be no air bubbles in the bottle
4) When taking a density bottle that has reached a constant temperature, do not directly touch the body of the density bottle with your hands to prevent the liquid from overflowing due to heating
5) Wear heat-insulating gloves to take the bottleneck of the volume screen or use tools to pick it up
6) The water in the Water Bath needs to be clean and free from oil to prevent the outer wall of the bottle from being polluted
7) The temperature of the balance room should not be higher than 20°C to prevent the liquid from expanding and flowing out
