Potato waste could offer the industry a cheap, renewable source of food additives, chitin and lactic acid, according to a university scientist.
Washington state university's Dr Shulin Chen has identified starch and nutrient-rich cull potatoes, as a potential raw material for the production of these important but expensive compounds.
With lactic acid making 50 cents a pound and pure chitin around $4,500 a pound at wholesale level, Chen's fermentation and separation process for cull potatoes could revolutionise both the ingredients industry and the fortunes of potato growers.
Lactic acid is a colourless compound, commonly used as a food additive for flavour and preservation.
It is usually produced from coal, petroleum, and natural gas, or plant carbohydrates.
Chitin is found primarily in the exoskeletons of crustaceans as well as in the cell walls of some fungi.
But studies on the production of lactic acid from potatoes have found that a considerable amount of fungal biomass is produced at the same time.
The biomass is almost pure chitin, which has been found to have several nutritional and physiological benefits.
Chen believes the process could be implemented in processing plants across the US, within five years.
However, production costs for the process are a strongly inhibiting factor despite its various advantages.
The technique would provide a lucrative outlet for cull potatoes which cannot be sold fresh or processed into chips and usually end up in further processing, on compost piles or fed to cattle.
Potatoes cost about $70 to $120 per tonne to grow while growers generally receive less than $10 a tonne for their culls.
But cull potatoes can be converted to approximately 94.5 million pounds of lactic acid which would yield $47 million in Washington alone.
In addition, the process could reduce the environmental impact of potato waste and the wastewater generated during processing by utilizing the starch and protein from the water which would otherwise carry some risk in being applied on land.
