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Kernel and Whole Wheat Tests
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Whole Wheat Crude Protein

Nitrogen combustion analysis using Elementar Nitrogen Analyzer. Units are recorded in % protein converted from nitrogen x 5.7 and expressed on 12% moisture basis.

Whole Wheat Falling Numbers

(AACC Method 56-81B) Units are expressed in seconds using the Perten Falling Numbers instrument.

Whole Wheat - Amylase Activity

(AACC Method 22-06) Units are expressed in alpha-amylase activity as SKB units/gram (@ 25?C).

Test Weight

(AACC Method 55-10) Weight per Winchester bushel of cleaned wheat subsequent to the removal of dockage using a Carter-Day dockage tester. Units are recorded as pounds/bushel (lb/bu) and kilograms/hectoliter (kg/hl).

1000-Kernel Weight

Units are recorded as grams/ 1000 kernels of cleaned wheat. There is little difference between 1000-kernel weight and milling quality when considering shriveled-free grain. However, small kernelled cultivars that have 1000-kernel weight below 30 grams likely will have reduced milling yield of about 0.75%.

Single Kernel Characterization System (SKCS)

(AACC Method 55-31) SKCS distribution showing % soft (A), semi-soft (B), semi-hard (C), and hard (D); SKCS hardness index; SKCS moisture content; SKCS kernel size; and SKCS kernel weight; along with standard deviations.

Whole Wheat Moisture

(AACC Method 44-15A) Air-oven method.

Whole Wheat Moisture

(Air-oven method, modified AACC 44-16)

Apparatus

  1. Tag-Heppenstall rolls
  2. Moisture dish (about 5.5cm diameter x 1.5cm height, with slipover lid)
  3. Air oven - a convection oven which maintains temperature 140 ? 1?C.
  4. Aluminum plate

Procedure

  1. Scoop out approximately one teaspoon of wheat into a moisture dish. As many as 36 samples may be run at once.
  2. Pass the wheat sample through the Tag-Heppenstall rolls with a pan placed below to collect the ground sample. The black knob on the side of the unit may be used to assist the wheat through the rolls if necessary. Transfer the ground sample to the moisture dish and cover the dish with a lid.
  3. Record the weight of the dish plus lid containing the ground sample (initial weight). Samples should be weighed soon after grinding and not allowed to sit for more than a few minutes in order to minimize moisture loss prior to weighing.
  4. Open the lid, and place the dish and lid in the oven at 140?C. Once all dishes and lids have been placed in the oven, allow the temperature to return to 140?C and set a timer for 90 minutes.
  5. At the end of the 90 minute drying time, cover the dishes with the lids and transfer them to an aluminum plate outside oven to cool for 5 minutes. It is recommended that no more than 12 dishes be taken out of the oven at once in order for the cooling time to remain consistent.
  6. Record the weight of the dish plus lid containing the dried flour (final weight). Continue weighing all dishes that have been taken out of the oven.
  7. Empty the samples from the dishes, brush any residue from the dishes and lids, and record the weights (dish weight).
  8. Percent moisture may be calculated using the following equation: 
    % Moisture = [(Initial Weight - Final Weight) 
    / (Initial Weight - Dish Weight)] * 100