Peltz will encourage Kraft to sell brands such as Post cereals and Maxwell House coffee in order to focus on improving its core frozen food and cheese businesses, according to an article published in the Financial Times last Friday.
The purchase is likely to lead to changes in Kraft's organisation as Peltz will look to boost profits, and it follows hot on the heels of his 3 per cent acquisition of confectionery company Cadbury.
An unnamed source told the FT that Peltz felt Kraft was not performing to its potential, and that a change to the balance sheet is needed.
Peltz will aim to increase company profit by realigning core businesses.
He will also invest more in better-performing segments such as groceries and frozen foods, the source added.
Sources familiar with Kraft told the FT that Kraft was keen on selling its Post cereal brands because of difficulties involved with selling it.
Kraft will focus on acquisitions outside the US in existing segments such as confectionery, snack and convenience food, and may consider purchasing Cadbury's London-based confectionery business, the source added.
Kraft Foods has not yet issued a statement.
Peltz, who heads Trian, a US-based hedge fund, is renowned in finance as an activist shareholder and has made changes at Heinz, where he now sits on the board, and at confectionery company Cadbury.
In March, Cadbury confirmed that Peltz and certain of his affiliates have interests in 62,465,267 Cadbury-Schweppes shares, representing 2.98 per cent of its share capital.
Several major changes in company structure have occurred since the purchase.
The same month the company announced the separation of its confectionery and beverage division, and pledged to spend £450m (€666m) on a cost reduction programme between 2007 and 2011.
Cadbury have also made recent acquisitions in the Turkish and Romanian confectionery markets, and have split responsibility for operations in Europe, Middle East and Africa into two.
Kraft Foods is currently one of the world's largest food and beverage companies, with global revenues of $34bn (€25bn), the company's website claims.
The snacks and confectionery sector is the largest sector driving company growth, generating $10bn (€7bn) in net revenue.
The company also claims to be the third largest seller of chocolates globally and market leader in 15 countries.
Brands include Milka, Toblerone, Freia, Marabou, Suchard and Côte d'Or.