Measures taken against water pollution in starch and potato processing industries.

The following measures are considered for the reduction and discharge of wastes from potato processing plants and starch mills; (a) Reduction of waste volume by in-plant measures such as recirculation, water re-use, changeover to other processes etc. (b) Reduction of pollutional load. 1. Manufacturing of by-products. 2. Purification processes. (c) Agricultural use. (d) Direct discharge into a receiving water with a great self-purifying capacity. 1. SURVEY OF PRODUCTION AND UTILIZATION OF POTATOES The International Symposium of 1965 at Fredericton, Canada on Utilization and disposal of potato wastes also dealt with this subject1. In Eastern Europe the emphasis is on quantity and total utilization of the potatoes (e.g. for livestock feed) while quality is steadily getting more attention2' . In the Western countries a condition of crop surplus has become usual. Heavy emphasis is given to improved quality at all levels to stop the decline in total and per capita consumption of potatoes. In the USA, Canada, Western Europe and Australia new human food uses have been developed since 1945. Regional preferences for potato products vary greatly. The frozen par-fried French fry potato is a major food product in North America, the long French fry of good texture being a premium item. In Europe, except for UK, Belgium and The Netherlands, this product is little known and instead a serious effort is being made to introduce the extruded 'pseudo French fry' made from dried potato mix. Dried dumpling mix is the major processed potato product in West Germany, while it is virtually unknown in North America. The Netherlands especially have sufficient raw material for the production of potato starch4. In this very important industry in The Netherlands more than 1 500000 tons of potatoes are milled for starch manufacture alone. The starch production in The Netherlands is about 300 000 tons per annum, which means around 80 per cent of the total production in the European