海鮮愛好者可能在吃假魚

海鮮愛好者可能在吃假魚

This is no post-Halloween prank — that swordfish you’re eating may be a shark in disguise.

這不是萬圣節(jié)后的惡作劇——你吃的旗魚可能是偽裝的鯊魚。

Thanks to a new genetic testing technique developed for the world’s fisheries, Italian researchers have estimated that 15 percent of all swordfish on the market is actually shark, specifically shortfin mako or blue shark, according to new research published in the journal Foods.

根據(jù)發(fā)表在《食品》(Foods)雜志上的一項(xiàng)新研究，得益于一項(xiàng)為全球漁業(yè)開發(fā)的新基因檢測技術(shù)，意大利研究人員估計(jì)，市場上所有劍魚中有15%實(shí)際上是鯊魚，特別是短鰭鯖魚或藍(lán)鯊。

And it’s not just sharks sneaking onto our plates.

不僅僅是鯊魚偷偷溜進(jìn)了我們的盤子。

A 2019 report by seafood watchdog group Oceana found that 21 percent of the seafood in the United States is being served under a fake identity — with sea bass, snapper, halibut, flounder, sole, lobster, catfish and scallops being the most commonly mislabeled foods.

海鮮監(jiān)督組織Oceana在2019年的一份報(bào)告中發(fā)現(xiàn)，美國有21%的海鮮是用假身份供應(yīng)的，其中，海鱸魚、鯛魚、大比目魚、各種比目魚、龍蝦、鯰魚和扇貝是最常見的貼錯(cuò)標(biāo)簽的食物。

Experts warn that the practice of passing off one fish for another can have a severe impact on biodiversity, and poses a threat to already over-fished species.

專家警告說，用一條魚冒充另一條魚的做法會(huì)嚴(yán)重影響生物多樣性，并對已經(jīng)過度捕撈的物種構(gòu)成威脅。

In the new study, scientists at the University of Catania in Sicily found that a DNA verification system, called COIBar–RFLP, could help reduce fish fraud. In the past, this method, referred to as genetic “barcoding,” was too time consuming and limited in its scope of aquatic species to make a big impact on the global fish supply. That might explain why the US, which imports 90 percent of its seafood, verifies just a mere one percent of its total intake.

在這項(xiàng)新的研究中，西西里卡塔尼亞大學(xué)的科學(xué)家們發(fā)現(xiàn)，一種名為COIBar-RFLP的DNA驗(yàn)證系統(tǒng)可以幫助減少魚類欺詐。過去，這種被稱為遺傳“條形碼”的方法耗時(shí)太長，而且其水生物種范圍有限，無法對全球魚類供應(yīng)產(chǎn)生重大影響。這或許可以解釋，為什么美國進(jìn)口了90%的海鮮，卻只驗(yàn)證了其總攝入量的1%。

However, researchers are improving the barcoding technique by narrowing their focus on the cytochrome oxidase I gene, which is considered unique enough across species to be a reliable indicator of fish type. Analyzing shorter sections of DNA should add to the database used to authenticate fish.

然而，研究人員正在改進(jìn)條形碼技術(shù)，縮小他們對細(xì)胞色素氧化酶I基因的關(guān)注范圍。細(xì)胞色素氧化酶I基因被認(rèn)為是一種獨(dú)特的跨物種的基因，是魚類類型的可靠指標(biāo)。分析較短的DNA片段應(yīng)該添加到用于鑒定魚的數(shù)據(jù)庫中。

The COIBar–RFLP method is also more efficient. While conventional DNA sequencing costs about $19 per sample and takes 24 hours to complete, the new test would only cost $11 and deliver results in just seven hours. Scientists also say the cost should decrease further over time.

COIBar-RFLP方法也更有效。傳統(tǒng)的DNA測序每個(gè)樣本的成本約為19美元，需要24小時(shí)才能完成，而新的檢測只需11美元，只需7小時(shí)就能得出結(jié)果?？茖W(xué)家還表示，隨著時(shí)間的推移，成本應(yīng)該會(huì)進(jìn)一步降低。