E-Delivery

28 Pulse crops retain their quality and maximize their marketability when a few grain storage guidelines are followed. Downgrading of pulses can occur when cracked seed coats or split seeds are present in the sample, or if a significant amount of seeds are heated or have a musty odour. The following table, set by the Canadian Grain Commission (CGC), indicates a dry seed per cent moisture content standard for safe storage and grading of common pulse crops. Crop Dry Pea 16 or less Red Len l 13 or less Green Len l 14 or less Faba Bean 16 or less Table 1: Dry Seed Per cent Moisture Content Source: Canadian Grain Commission. Monitoring stored pulses begins shortly a er harvest with grain spoilage risk increasing if the crop was harvested a er wet weather or an early frost. Since pulses are combined at tough or higher seed moisture content to prevent mechanical damage to the seeds, aera on is used to bring the crop down to dry. Dr. Joy Agnew of the Prairie Agriculture Machinery Ins tute (PAMI) claims that since pulses are harvested early, the weather generally cooperates for effec ve aera on and natural air drying; addi onal AERATION AND DRYING OF PULSE CROPS CROP STORAGE heat with a supplemental hea ng system is usually not required. Green seeds, dockage and foreign material hold moisture and should therefore be cleaned out of the sample prior to storage to avoid hea ng in the bin. They can also reduce aera on air flow. Generally pulse crop seeds con nue to respire or breathe a er being harvested, causing the crop to go through a 'sweat' period for the ini al six weeks in storage. This swea ng can raise the grain temperature and cause moisture to accumulate within the grain mass, producing favourable condi ons for mould growth. Using aera on bins is the most effec ve method to control this situa on. Whether to use aera on, natural air drying (NAD) without addi onal heat or a heated air drying system depends on the grain's moisture content. If the grain is somewhat tough at 1-2% moisture content above dry, aera on is usually sufficient. However, if the grain must come down 3-4% moisture content, a NAD system removes this extra moisture. While aera on can be completed in a few days, drying can take a couple weeks. If only aera on is required, PAMI advises producers to turn aera on fans on as soon as the ducts are covered with grain and run them con nuously un l the average temperature of the grain is at "Generally pulse crop seeds continue to respire or breathe after being harvested, causing the crop to go through a 'sweat' period..." Neil Whatley, Alberta Agriculture and Forestry

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