A report in Business Insider reveals that in case the grape colour of a bunch matches that with the approved palette, then it can fetch a price anywhere between 90 to 450 USD.

There is more to the grapes than just colour and prices that make them famous. Every bunch of these grapes are examined closely before being given approval.

The criteria for their selection is based on their unusual size, uniform colour and taste.

According to Hiroshi Isu who is the chief researcher at the Ishikawa Prefectural University in Japan, there is no other variety in the world as large and red as the Ruby Roman. That is why these fruits are so valuable, he added.

Speaking to Business Insider, Kazuyoshi Sakurai, an inspector of Ruby Roman grapes at Japan Agricultural Cooperatives, said that they use very specific criteria to scrutinise each grape that grows in Kahoku city. He said: “The first is the Ruby Roman’s colour. The second is the size of the grains. Each grape must be at least 20 grams and we make sure that it is at least 30 millimetres in size.”

Further, he added, that the sugar content is also measured and must be over 18 per cent.

A video on Business Insider Twitter explains how are the grapes are chosen

Why Japanese Ruby Roman grapes are so expensive pic.twitter.com/PxDDP3u4zf

— Business Insider (@BusinessInsider) September 17, 2021

These grapes are categorized in three groups, namely, superior grapes, special superior grapes and premium.

The normal Ruby Roman grape grain is around 20 grams, the premium needs to be more than 30, said Sakurai. It is only one or two bunches that are categorized as premium.

Irrespective of their groups, all the Ruby Roman grapes have a uniquely sweet flavour.

This year two bunches made the cut while in 2020 and 2019 no bunch qualified for the premium quality. In 2020, a single bunch of Ruby Roman grapes sold for $12,000 at an auction.

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