To eat or not to eat wheat starch-containing gluten-free DiGiorno pizza
The controversy over the use of wheat starch in gluten-free foods is back on the front burner due to the new DiGiorno gluten-free pizzas. The pizzas are made using wheat starch that has been processed to remove gluten.
Before we go any further, please remember that under the FDA’s 2013 gluten-free labeling rule, wheat starch is an allowed ingredient in foods labeled gluten-free as long as its use does not result in the final food product containing 20 parts per million or more of gluten. Please avoid wheat starch containing foods NOT labeled gluten-free.
If you would like to eat a wheat starch-containing food labeled gluten-free food, it is prudent to make sure at least one of the following is true:
- It is confirmed by the manufacturer that 1. Hydrolytic enzymes are not used in the production process of water washed wheat starch, and 2. Wheat starch is tested with a sandwich ELISA.
- It is confirmed by the manufacturer that both the sandwich and competitive R5 ELISAs are used to assess the wheat starch for gluten.
To learn the why for the above recommendation, please read on…
Gluten Free Watchdog testing
GFWD tested four DiGiorno gluten-free pizzas—two pepperoni pizzas and two cheese pizzas. Extractions from both the whole pizza (crust and toppings) and the crust only were tested.
Summary of what we found
Sandwich R5 ELISA (quantifies intact gluten): All 16 extractions from samples of both the whole pizza and the crust only contained a level of gluten below the lower limit of quantification of 5 parts per million.
Competitive R5 ELISA (detects gluten protein fragments): All 16 extractions from samples of both the whole pizza and the crust only contained a level of gluten below the lower limit of quantification of 10 parts per million.
Are DiGiorno gluten-free pizzas appropriate for folks with celiac disease?
Maybe. The gluten content of wheat starch can vary and GFWD would feel much more comfortable providing an assessment on safety if we knew:
1. The assays used by DiGiorno and their supplier to test wheat starch for gluten.
2. The process used by their supplier in the production of wheat starch (e.g., are hydrolytic enzymes used).
Why the cautionary note? Because of what assay manufacturer R-Biopharm has to say about testing wheat starch for gluten…
Under certain circumstances, R-Biopharm, the manufacturer of the sandwich and competitive R5 ELISAs recommends the use of the competitive R5 ELISA when assessing wheat starch for gluten.
GFWD question to R-Biopharm: Do you still recommend using the competitive R5 ELISA when assessing starch for gluten? If yes, does this include water washed wheat starch?
Response from R-Biopharm: Thank you for asking. The answer unfortunately is “it depends”… If hydrolytic enzymes were used in the production process of (water washed) starch the use of R7021 (competitive ELISA) is the better choice. If hydrolysis can be excluded R7001 works fine.
Information from DiGiorno
DiGiorno states on their website that they use wheat starch that undergoes a rinsing process, “We extract the starch from the wheat and then rinse the starch to remove the gluten.” They do not state whether or not the process involves hydrolytic enzymes.
It is likely next to impossible for consumers to find out if a supplier uses hydrolytic enzymes during the production process of water washed wheat starch. A less frustrating approach may be to ask the manufacturer if they or their supplier test wheat starch using the competitive R5 ELISA. However, this question may be met with silence as well.
Gluten Free Watchdog reached out to DiGiorno, Schar, and Caputo to ask about the testing and extraction processes for the wheat starch used in their products.
DiGiorno: Has not yet responded.
Schar: Hydrolytic enzymes are NOT used in the production process of water washed wheat starch AND both a sandwich and competitive ELISA are used to assess wheat starch for gluten.
Caputo: Has not yet responded.
If a wheat starch-containing product is certified by GFCO
GFCO stated in email correspondence that they certify very few products with wheat starch, but that with an increase in interest they are updating their policies to clarify that wheat starch must be water washed only (without the use of hydrolytic enzymes), and that the starch must test below the lower limit of quantification (no more than 5 ppm of gluten) using a sandwich ELISA.
DiGiorno states on their website that their pizzas are not currently certified but they are in the process of obtaining certification. They do not name the certification organization.
What to do if you believe a wheat starch-containing food made you sick
Contact an FDA Consumer Complaint Coordinator in your state/region and file a report. See https://www.fda.gov/safety/report-problem-fda/consumer-complaint-coordinators.
For more information on wheat starch, see https://www.glutenfreewatchdog.org/news/what-the-fda-has-to-say-about-wheat-starch-and-hydrolyzed-gluten/