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Get to know more about food testing laboratory
Food includes rough-processed agricultural products and deep-processed agricultural products. The former include vegetables, aquatic products, grains, oilseeds, livestock and poultry products, etc., and the latter include condiments, edible oils, instant noodles, canned food, ham sausage, etc. Food safety is getting more and more attention, and food testing laboratories, microbiology laboratories, and sterile rooms are being upgraded. However, due to the different service objects of food testing laboratories, the testing items are different, and there are different requirements for the selection and configuration of instruments and equipment in the laboratory preparation and upgrading. According to the years of experience in the food testing field, Alfa chemistry has put forward some suggestions.
The most extensive are first-party and second-party laboratories, that is, internal quality inspection laboratories and quality inspection laboratories for upstream suppliers. Such laboratories instruments and equipment can be configured according to the product variety, production scale, and number of testing items. The food inspection of the internal quality inspection department of an enterprise can be divided into two major parts, one is the quality detection; the other is the health detection, which is relatively difficult and expensive.
Quality testing includes: moisture, acidity, salinity, sugar, protein, fat, fiber, vitamin content, etc. For the detection of these physical and chemical laboratory projects, if the funding is limited, physical and chemical analysis can be used, and only the simplest oven, water bath, electric furnace, stirrer, pulverizer, pH meter and other equipment can be configured. If the funding is sufficient or there are many inspection batches, the corresponding physical and chemical laboratory test items have special instruments available for purchase. In addition, there are also some general-purpose instruments available for purchase, such as: UV / visible spectrophotometer, near-infrared analyzer, automatic titrator, and so on. Fluorescence photometer is sometimes required to detect vitamin A, E, etc. To detect nutrient elements, such as calcium, zinc, iron, etc., atomic absorption instrument-flame detector can be purchased.
Health testing include pesticide residues, veterinary drug residues, toxins, microorganisms, additives, and harmful elements. Among them, microbiology laboratories have small investment and extensive testing projects, and they should all be considered for establishment.
To carry out pesticide residue detection, gas chromatography is indispensable. To detect organochlorine pesticides, an electron capture ECD detector is required. To detect organophosphorus pesticides, a flame photometric FPD detector or a nitrogen phosphorus NPD detector is required. Currently, there are more and more pesticide residue testing items. In order to improve the versatility, it is recommended to configure a capillary column split / splitless inlet and install a capillary column. Compared with traditional packed column chromatography columns, capillary columns have more analysis items and good resolution, which can reduce frequent column replacements and improve analysis efficiency. There are more and more pesticide residue items that export food processing companies need to test when exporting. In order to control the quality of raw materials and products, gas chromatography-mass spectrometry can be configured. Generally only need to configure the electron bombardment EI source, if necessary, can be equipped with a negative chemical NCI source. Whether you choose quadrupole mass spectrometry or ion trap mass spectrometry, I personally think that both can be used. Both instruments have advantages and disadvantages. It depends on the specific job.
There are not many items and many batches of veterinary drug residue detection. You can consider configuring an enzyme-linked immunoassay instrument. The instrument has a small investment at one time, is easy to operate, and has high detection sensitivity. There are also some disadvantages to using ELISA. First, the kit is a long-term consumable. The cost will be higher if the number of test batches is small. Second, the specificity is not good, and there may be false positives. There are many testing items, and the cost is even higher than the instrumental analysis. For exporting food companies with a certain scale, in order to meet the current testing limit requirements of developed countries such as the European Union, the United States, and Japan, it is best to configure a liquid chromatography-tandem mass spectrometer. The first instrument is recommended to be equipped with a triple quadrupole mass spectrometer, which has high sensitivity and good reproducibility. The instrument does not have to pursue high configuration, it is enough to be sufficient, but the performance such as sensitivity, stability, anti-pollution is better. It is best to buy a model with a large number of users. There is a user group that is similar to its own test items. First of all, it indicates that there is no problem in the test items of this type of instrument. Second, it also facilitates future technical exchanges.
The microbiology laboratory shall be laid out in accordance with the requirements of the General Requirements for Laboratory Biosafety and the Technical Specifications for the Construction of Clean Houses in the Food Industry. The necessary equipment includes biological safety cabinets, incubators, autoclaves, and electric stoves, etc. Other equipment is configured according to the specific test items.
Some of the items for the detection of toxins, additives and harmful elements can be used in physical and chemical laboratory physical and chemical methods, such as heavy metal content, total arsenic, nitrite, sulfur dioxide and so on. But in order to meet the current national food hygiene requirements, gas chromatography-hydrogen flame detectors, liquid chromatography-ultraviolet / visible light detectors should be purchased. Such general preservatives (benzoic acid, sorbic acid, etc.), sweeteners (sweetness) pigment, sodium saccharin, etc.), pigments (lime yellow, carmine, etc.) can be detected. Atomic absorption instrument-graphite furnace detector is purchased, which can detect harmful elements such as lead, chromium, cadmium, copper, nickel, etc., and an atomic fluorescence meter is needed to detect arsenic and mercury.
Third-party laboratories refer to laboratories with independent legal person status, national and industry certifications, which can provide testing or calibration services to society, and commercial laboratories whose data is widely recognized by society. Compared with the first and second party laboratories, this kind of laboratories have a wider range of commodities and items tested, so the configuration of instruments and equipment should be more complete in terms of categories and quantities.
Quality testing usually requires consideration of the standards used or configuration of corresponding testing instruments and equipment according to customer requirements. Since different products and different customers may propose different detection standards or methods for the same item, for the detection of these items, if the method requires the use of physical and chemical laboratory chemistry analysis, only the simplest equipment can be configured. If the funding is sufficient or there are many inspection batches, you can configure the corresponding physical and chemical laboratory dedicated instruments, such as moisture analyzer, Kjeldahl nitrogen analyzer, fast fat analyzer, sugar meter, viscometer, fatty acid analyzer, etc. General instruments can also refer to the section of the enterprise laboratory quality project. If required, a dedicated analyzer such as an amino acid analyzer can also be configured.
It is indispensable to configure liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry in laboratories for sanitation testing. This is a condition required by directives and standards when a positive report is issued for banned agricultural and veterinary drug residues. If there are scale and testing items, each type of instrument should be equipped with multiple sets. At this time, the complementarity of instrument performance should be considered, such as liquid chromatography-tandem mass spectrometry, one power distribution spray ionization source, one equipped with atmospheric pressure chemical ionization source; gas chromatography-mass spectrometry, one equipped with electron bombardment source, and one equipped with negative chemical ionization. source. There are many elements and samples are miscellaneous. Plasma emission spectrometry-mass spectrometry, gas chromatography-tandem mass spectrometry can also be considered. If morphological analysis is to be performed, the plasma emission spectrometer-mass spectrometer should also be able to be used with liquid chromatography or gas chromatography.
Except for the first, second, and third-party government regulatory laboratories, they generally have administrative functions and are mostly affiliated with administrative departments in different industries. In recent years, the government attaches great importance to food safety and has increased its investment. Therefore, the laboratory hardware has been greatly improved. At present, a relatively complete government-regulated laboratory (above the provincial and municipal level), in addition to the types and quantity of analysis and testing equipment, should be equal to or better than ordinary first, second, and third-party laboratories. It can be more perfect in the configuration of pretreatment equipment, such as: microwave digestion (including microwave extraction), automatic solid-phase extraction instrument, gel chromatography purification instrument, solvent accelerated extraction instrument, high-speed refrigerated centrifuge, high-speed homogenizer, nitrogen blowing Instrument and so on. These pre-processing equipment are more efficient, more automated (the samples can be processed automatically at night time), and will improve the reproducibility of results.
Alfa Chemistry is an analytical testing company that provides one-stop testing, analysis and technical support services in the areas of pharmaceutical analysis, environmental analysis, consumer product analysis, food analysis, and material analysis. As a professional testing and analysis organization, Alfa Chemistry has an experienced technical team that uses advanced analytical equipment and technology to meet the needs of different customers.