Shares in Kerry Group fell 2.8% in Dublin today after it lost out in its bid to acquire the nutrition and biosciences business of the US chemicals group DuPont.

At over €22 billion, it is believed the transaction would have been the biggest deal carried out by an ISEQ listed company. 

DuPont has opted instead to merge its nutrition division with the New York-based International Flavors & Fragrances, or IFF. 

In a statement, DuPont said the deal valued the Nutrition and Biosciences (N&B) business of DuPont at $26.2 billion based on IFF's share price on Friday. 

DuPont's shareholders will own 55.4% of the shares of the new company. 

Kerry Group had been the leading contender to acquire the business.

A merger would have doubled the size of the company and would have seen it overtake CRH to become the biggest business on the Irish stock exchange.

Kerry Group has long wanted to expand in healthy bacteria strains, ingredients found in dietary supplements, cheese and bakery products, and nutritional products that claim to have some sort of role in assisting in disease treatment or prevention.

DuPont, under Chairman Ed Breen and CEO Marc Doyle, opted for the most tax-efficient option to reward shareholders after the value of its nutrition business was stuck below industry levels as part of a diversified company. 

The deal is be the biggest ever for IFF, which creates flavours and fragrances and works with global brands to develop scents and tastes for products that are household names.

The company's last big acquisition was in the food-flavouring industry last year, when it bought Israel's Frutarom Industries for $7.1 billion including debt.

The deal will be executed using a tax-efficient structure called a Reverse Morris Trust, IFF said. 

Such transactions let a company avoid a big tax bill by spinning off a unit that it wants to divest and simultaneously merging it with another company. 

After the deal closes, IFF expects cost savings of about $300m by the end of third year. 

The companies said they have obtained fully-committed debt financing from Morgan Stanley and Credit Suisse.