Britain's second richest man, Hans Rausing, owes it all to the ubiquitous Tetra Pak cardboard container. At the age of 74, however, rather than enjoy his retirement Rausing is embarking on a new milk packaging revolution, producing biodegradable bottles out of chalk.

The last five years have seen little commercial packaging inactivity for Rausing, a period enforced by a 1995 deal in which he sold his share of the family Tetra empire to his brother Gad for an estimated £4bn (US$5.6bn). During this time a small Swedish company called EcoLean was born and once he was released by the contract in 2000, Rausing bought a majority stake of 57% in EcoLean.

EcoLean, which offers "the material for the new mil-lean-ium", uses eggs for packaging inspiration. Egg shells consist of 95% chalk (calcium carbonate) held together with 5% binding agent. By mimicking this structure on a larger and stronger scale, EcoLean hopes to solve the global problems of litter because its product is fully biodegradable.

Produced from chalk bound with polyolefins, plastic derived from natural gas, the durable and lightweight shells actually break down into oxygen, carbon and chalk dust when exposed to sunlight, and are completely harmless to the environment. Furthermore the LeanMaterial is cost competitive to produce and as a raw material chalk is in abundance.

Currently the new packaging is only being used in one small dairy in southern Sweden, which is treated by EcoLean's chemists as a small scale field trial for the company, but as far as Rausing is concerned this is the "first important news in food packaging for 30 years." Watch this space.