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Public Meeting on Gluten-Free Food Labeling - Text Version of PowerPoint Presentation by Jane DeMarchi

Public Meeting: Gluten-Free Labeling main page

Slide 1 - Feasibility of Milling Gluten-Free Flours

Jane DeMarchi
North American Millers’ Association
August 19, 2005

Slide 2 - North American Millers’ Association

  • 96% of the US milling capacity for the wheat, corn and oat milling industry
  • More than 160 million pounds daily
  • 48 corporate members
  • Supply products to bakers, cereal makers, packaged food companies, brewers, and directly to retail

Slide 3 - Cross Contact Begins at the Farm

  • Producers often rotate wheat, barley, rye and oats on same land - volunteer plants in subsequent years
  • Several crops may be grown in close proximity on one farm
  • Great variability from year to year due to weather, etc.
  • Farms use the same harvesting, transport, and storage equipment without significant clean out
  • Some corn and oats are purchased on a contract basis for greater control but mixture is not eliminated in these cases

Slide 4 - Grain Storage & Transportation

  • Trucks and rail cars used to transport grain are another source of cross contact
  • Grain elevators do not thoroughly clean out silos or equipment when switching grains - in part to minimize dust for health and safety
  • Elevators have basic equipment to clean grain but not specifically to separate mixed grain

Slide 5 - Grain Specifications Allow Other Grains

  • Grain specifications are based on the US Grain Standards
  • Oats
    • Typically contain 0.5-1.0% cereal grain admix
    • Maximum of 2-3% allowed depending on the grade
  • Corn
    • 2-4% broken corn and “foreign” material depending on the grade
    • Milling quality specifications may be more restrictive

Slide 6 - The Milling Process

  • Grain “cleaned” prior to milling
    • Width grading - sieves
    • Length grading - rotating drums
    • Density separation - gravity tables
  • Grains that are very different in size and shape (such as wheat and corn) are easier to separate than like-sized grains

Slide 7 - Deficiencies of Cleaning Technology

  • Length, width and weight of kernels of different grain can be similar in many circumstances

Four photos displayed. One of Barley seeds up close, one of Oats up close, one of Rye up close, and one of Wheat up close. 

Slide 8 - New Technology

  • Color or optical sorting machines
    • Expensive
    • Low capacity
    • Not reliable - if color differences are small

Slide 9 - Internal Cleaning Procedures

  • Good Manufacturing Practices
    • Mill equipment is regularly cleaned and inspected. It is critically important to a mill that product dust not be allowed to gather.
    • Internal cleaning is dry cleaning, vacuum and wipe out
    • Special procedures are used for changing grains.
  • HACCP includes analysis of allergen risk.

Slide 10 - Testing

  • Corn and wheat mills generally do not conduct tests for cross contamination on finished product.
  • ELISA tests are not used for cross contact of grains in mills. Granulation and small test samples cause results to vary dramatically
  • In an oat mill, representative samples are hand sorted and visually inspected

Slide 11 - Economics of Grain Milling

  • Many mills are dedicated to a single grain or have dedicated lines
  • Mills operate as close to 24/7 as possible
  • Shut down time is minimized
  • Cross contact grains can not be cleaned out 100%. Mills can not lose too much of the desired grain in the separation process
  • Testing every bag of product is not feasible
  • Emphasis on prevention

Slide 12 - Concentrations of Gluten Bearing Cereal Admix

  • Research has not been done to quantify the levels of cereal admix in oats or corn on an industry wide basis.
  • Individual customers may establish standards but so far it is not common
  • Variability from year to year is large

Slide 13 - Trace Grains In Finished Products

  • Varies depending on product and portion size. Concentrations of wheat protein in oat flour will be higher than those in oat flakes due to the milling process.
  • Example: 28 gram serving of instant oatmeal
    • 7.5 milligrams of wheat and barley protein - approximately 40% (3 milligrams) of which would be gluten.
      (Assumes a .03% contamination of wheat at 15% protein and barley contamination of .16% at 14% protein content)

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