Transformation of vegetable waste into value added products: (A) the upgrading concept; (B) practical implementations

Waste can contain many reusable substances of high value. Depending on there being an adequate technology this residual matter can be converted into commercial products either as raw material for secondary processes, as operating supplies or as ingredients of new products. Numerous valuable substances in food production are suitable for separation and recycling at the end of their life cycle, even though present separation and recycling processes are not absolutely cost efficient. In Part A a need statement is visualised––based on a holistic concept of food production-–for the vegetable industry, recording occurrence, quantities and utilisation of the residual products. A literature survey, covering more than 160 articles from all over the world, plus our own investigations summarises the latest knowledge in the above mentioned field and outline prospects for future economic treatment of vegetable ‘co-products’. The main goal of a clean production process is demonstrated by three practical implementations in Part B: 1. Upgrading of vegetable residues for the production of novel types of products: multifunctional food ingredients in fruit juice and bakery goods. 2. Bioconversion via solid-state fermentation: vegetable residues as an exclusive substrate for the generation of fruity food flavours. 3. Conversion of vegetable residues into operating supplies: bioadsorbents for waste water treatment. The investigations are promising with regard to future application in the mentioned industrial branch. The outlined concept can be naturally transferred to several areas of industrial food production. The intentions of this research area are located at the development of techniques, which fulfil the conditions of environmental protection with costs to a minimum. The prospect of several new niche markets is worthwhile indeed. (C) 2002 Elsevier Science Ltd