The effect of storage conditions on the quality of Australian canola (rapeseed), Brassica napus L.

In 2002-03, 1.6 million tonnes of canola (rapeseed) are expected to be harvested in Australia. Increased production of canola has resulted in more prolonged storage before end use or export. This paper examines the effect of storage conditions and storage period on the quality of two Australian canola cultivars. Samples of the cultivars "Oscar" and "Pinnacle" were conditioned to moisture contents of 6, 7 and 8% and stored at 20, 25 and 30 degrees C for a period of nine months. There were measurable differences between freshly harvested canola and stored canola. Changes were mostly dependent on the storage conditions, but differences between cultivars and the intake condition of the grain were also important. Generally, the most significant changes occurred at the highest moisture content (m.c.) and storage temperatures. Loss in germination energy reflected the intake quality of canola and storage at high temperatures and moderate m.c. Seed coat colour changes were an indicator of chemical changes during storage. Changes in the UV-visible spectra of canola oil, fatty acid composition, and NIR spectra were also influenced by storage parameters. Free fatty acid accumulation was the most useful indicator of potential storage-induced quality loss. Future work will include data on storage periods of less than nine months and detailed analysis of chemical, biological and chemometric data.