Biology classes are often much more interesting when teachers propose a practical activity, as Jennifer McDonald did with her students from Fanshawe College in Ontario – Canada. The young teacher asked her students to go to Japanese restaurants to collect samples of raw fish, which were then analyzed in the school lab. And the result will shock you, just as it shocked the Internet this week, since Jennifer shared on her Twitter that the vast majority of the samples were no longer frauds. The students, who were studying polymerase chain reactions, took advantage of the fishes to use a laboratory technique used to make multiple copies of a DNA segment, which enables fraud detection. But what do you mean, fraud? There are several studies showing that 74% of the fish sold in restaurants are erroneously labeled. In other words, you pay dearly for thinking you're eating something, when you're actually eating another.
Food fraud is an annual industry of over 50 billion dollars that does not only happen in Japanese food restaurants, but can also be found in supermarkets around the world, as Jennifer and her students have noticed. Tuna, for example, was not tuna, but a tilapia. The same happened with all the other samples, since they were sold as more expensive fish, such as tuna and salmon, when in fact they were cheap fish, which exist in abundance. In doubt, buy your fish in trusted fish shops and prepare yourself your own sushi!