Is there any secret to the delicious crayfish that can't stop eating?

--------Ohouse supports crayfish food safety testing (Part 3)

Some people say that summer is the season for crayfish - beer crayfish, and Duan You is one of them. In the scorching summer sun, drinking refreshing draft beer paired with spicy crayfish is incredibly satisfying ... A pot full of crayfish is served, bright red, hot, and coated with soup. First, suck on the shrimp head, then hold the shrimp tail and bite off the entire shrimp meat, firm and rich.

Some people also say that crayfish is such a magical delicacy that can make you throw away your phone and all the distractions in your hands, and seriously enjoy the pleasure brought by each shrimp; As long as you see these red shrimp shells, plump shrimp roe, and chewy shrimp meat, your mind is filled with thoughts that can't stop eating.

In the first two episodes, the editor introduced the detection of heavy metal content and veterinary drug residues in crayfish. Today, we will explore the rumor in the martial arts world: Is eating addictive crayfish adding illegal additives?

The harm of residual substances in food to human health has gradually attracted people's attention. In recent years, many methods have been established for the detection of water leaching residues in food seasonings, such as spectrophotometry, thin-layer chromatography, gas chromatography, liquid chromatography, gas chromatography-mass spectrometry, etc. Let's discuss spectrophotometry and thin-layer chromatography today.

Thin layer chromatography (TLC) 

Accurately weigh 10g of poppy seed and shell powder samples, place them in a Soxhlet extractor and add 200ml of 95% ethanol. Reflux and extract for 8 hours in a water bath, evaporate the solvent (to keep the total volume of the liquid below 5ml), cool and transfer to a 10ml volumetric flask. Add 95% ethanol to the mark and shake well. Take 4 μ l of the sample and place it on a silica gel plate. After unfolding, scan and measure it. Extract, spot, unfold, and scan the sample and the sample with a known amount of alkaloids separately, and use subtraction to determine the recovery rate of each alkaloid added. From the results, it can be seen that this method has a high recovery rate. Comparing the results of three measurements of each alkaloid, it can be seen that this method has good reproducibility.

Equip experimental instruments for testing work

Food safety testing is a very delicate process that requires specialized knowledge, precision, and highly controllable laboratory equipment. Equipping appropriate equipment for testing projects is the beginning of the experiment.

Some people say that 'choosing a suitable sample pretreatment method is equivalent to completing half of the analysis work', which perfectly reflects the importance of sample pretreatment. During sample pretreatment, the laboratory should include an analytical balance, homogenizer, centrifuge, and constant temperature freezer shaker. To extract 0.01g of sample from difficult to process samples, a high-quality homogenizer is required. Due to the involvement of multiple sample sizes in detection work, homogenizers should have flexibility in use. Statistical data shows that linear motion can decompose samples more effectively than horizontal motion, thereby improving extraction rates and ultimately increasing the number of available samples.

High quality centrifuges are also included in this testing project. Used to separate solid particles from liquids in suspension, or to separate two immiscible liquids with different densities in emulsion. This is an important experimental step in sample pretreatment. OHAUS provides high-quality centrifuges with various rotors to meet the centrifugal separation needs of various samples and offer flexibility. Therefore, researchers can produce reproducible results without worrying about machine wear and tear.

The durability of the shaker is also an issue. OHAUS has various structures of shaking tables that can withstand temperature fluctuations, including high load circular shaking tables, mixers, and environmental shaking tables, and can withstand up to humidity. What I don't want during the testing process is to return to the laboratory and discover machine malfunctions or experimental failures. That's why reliable laboratory equipment is crucial for testing work.

Through professional testing agencies, no illegal additives were detected in the four samples of "internet famous" crayfish. Based on the results of this random sampling test of "internet famous" crayfish shops, the quality of crayfish is still quite reassuring.

It's time to finish work and invite three to five friends to go eat crayfish together. What could be better than this?