Xanthan gum in formulas for special medical purposes for infants
In December 2021, 7 years after ISDI asked JECFA – the Joint FAO/WHO Expert Committee on Food Additives – to evaluate the use of xanthan gum in formulas for special medical purposes for infants, its inclusion in the General Standard for Food Additives (GSFA) was finally adopted at the 44th session of the Codex Alimentarius Commission (CAC44).
We spoke to Dr Paul Hanlon Ph.D., DABT, Director of Regulatory Affairs at Abbott Nutrition and Chair of the ISDI Food Safety and Food Additives Working Groups about how it happened and why it matters.
When did the whole xanthan gum story start and why?
Standard infant formulas rely on intact proteins from high quality sources such as milk or soy. Unfortunately, some infants are born with conditions such as allergies to intact proteins that make them unable to consume these products. For these infants, infant formulas produced with hydrolysed proteins are an option, but only if those products can be manufactured in a manner that ensures the consistent delivery of the nutrition that infants need. The nature of hydrolysed proteins results in products that cannot maintain homogeneity during standard storage and use conditions without the help of food additives.
Several food additives have been demonstrated to be able to achieve the technological effect of maintaining the homogeneity of infant formula products that rely on hydrolysed protein. The effectivity of different additives in a product is influenced by many factors specific to a product, including the product format, manufacturing conditions, and the formulation. In some products, xanthan gum has been demonstrated to perform better than other available additives in maintaining the homogeneity of these products.
While xanthan gum has been approved for use in countries for many years and has been used in marketed infant formula FSMP products in many countries, xanthan gum had not been authorised for use in infant formula by Codex until 2021.
What about the safety assessment of xanthan gum? How did that happen and what were the results?
One of the foundations of Codex is creating food standards focused on ensuring the safety of food, and this is an element that is applied to the consideration of all food additives. JECFA, the scientific risk assessment body for Codex, conducts a safety evaluation of all food additives prior to their authorisation. The JECFA safety evaluation considers everything about the additive, including how it is manufactured, what products it will be used in, the concentration it is used in those products and which individuals consume those products.
For xanthan gum, the JECFA safety assessment considered that this additive was going to be in products intended for consumption by infants, including those under 16 weeks of age. Infants of this age have been identified as an especially sensitive population, and because of that the safety of this additive was supported by data that is typically not included in safety assessments of additives used only in non-infant products, such as a study conducted in new-born piglets, as well as outcomes from clinical studies in human infants.
After reviewing all of the data for xanthan gum, JECFA concluded at their 82nd meeting in 2016 that “the consumption of xanthan gum in infant formula or formula for special medical purposes intended for infants is of no safety concern at the maximum proposed use level of 1000 mg/L.”
From there, how did the discussions start in CCNFSDU?
The conclusions from the JECFA safety assessment were published in June 2016. In December that year, the positive outcome of the JECFA safety assessment was raised at the CCNFSDU meeting, and ISDI submitted a Conference Room Document (CRD) in advance of the meeting providing the technological justification for the use of this additive in specific infant formula products.
At the 2016 CCNFSDU meeting, the committee determined that there had not been enough time for Codex members to consider the technological justification provided by ISDI. Furthermore, the committee agreed that it would be beneficial to develop a more structured framework for judging whether an additive met the criteria for technological need. CCNFSDU therefore set up a working group to develop this new framework, and xanthan gum was identified as one of the additives that would be used to pilot these criteria.
What was the appraisal process for evaluating the technological need of xanthan gum in infant formula and FSMPs?
The evaluation of the technological need for xanthan gum evolved as the CCNFSDU working group developed the criteria. That work started in the summer of 2017, when the first draft of the criteria was circulated for comment. The criteria were refined over several rounds of comments in electronic working groups and discussions at the CCNFSDU plenary sessions in 2017 and 2018. The criteria were finalised in 2019 after a highly effective physical meeting of the working group that was held the day before the CCNFSDU plenary.
Throughout that process, the technological justification for xanthan gum was adapted to align with the developing criteria, although the underlying rationale never changed. Infant formula products, especially those produced with ingredients like hydrolysed proteins, represent a huge technological challenge, especially when considering that the resulting products must be able to consistently provide the same nutrition over the life of the product and under all potential use scenarios.
We demonstrated through a set of experiments that under our particular product conditions (including production method, product format and product composition) xanthan gum was able to maintain homogeneity at a lower concentration than other additives. Infant formula manufacturers strive to minimise the amount of food additives in the products we produce, and having a variety of food additives authorised within the same technological function allows manufacturers to optimise products by using the additives that are the most effective at the lowest amount possible.
Once the provisions were adopted in the standards, what were the next steps?
At the same meeting where the working group finalised the criteria for evaluating the technological need, the working group also concluded that xanthan gum met these criteria. The recommendation from this working group was then reviewed at the CCNFSDU plenary session, where the committee aligned to this assessment and made the recommendation to add this authorisation to the Codex Infant Formula Standard (Codex Stan 72-1981). From there, the Codex procedure took over with the Codex Alimentarius Commission adopting the recommendation to amend the Infant Formula Standard in 2020, and with the Codex Committee on Food Additives (CCFA) then updating the General Standard for Food Additives (Codex Stan 192-1995) in 2021.
What is next for infant formula additives at Codex?
The work at Codex is never done, and the good news is that after the hard work over the last few years on establishing processes for reviewing additives we have a clear infrastructure in place to review infant formula additives. In fact, there is already another infant formula additive that has begun moving through the process. Similar to the story of xanthan gum, we have found another stabiliser/thickener called gellan gum is able to accomplish the technological need of maintaining homogeneity in certain products at concentrations lower than other additives. Gellan gum was determined by JECFA to be safe for consumption by infants less than 12 weeks of age in their 87th meeting in 2019, so it has already met some of the criteria for authorising its use.
Unfortunately, the safety determination for gellan gum was published at the last in-person CCNFSDU meeting and right before the pandemic hit. It was identified as the next additive to test the newly established criteria for evaluating technological need, but with the pandemic disruption of many Codex activities, discussions have stalled. The technological justification for gellan gum, including comparisons with other additives showing its superiority at lower concentrations, was shared with Codex members who are participating in the electronic working group that was initiated in 2020, and at this point we are waiting for the endorsement of that group so that it can be discussed at the next CCNFSDU plenary.
From there, we will have several good examples (xanthan gum, gellan gum, pectins) of how additives proceed through the process. This will be a big help, since we won’t have to carve out the path next time, just follow it. When infant formula manufacturers have more scientific advances that identify safe food additives that are effective at even lower concentrations, this will make it easier to get those additives authorised at Codex and help make these advances so that we can continually reduce the amount of food additives needed in these products.
The xanthan gum story actually started a few years before the work at Codex began with its addition to the JECFA priority list in 2015. A lot of work was conducted prior to this to build up the science that was needed to demonstrate the safety of that additive, and many of those studies were conducted years before addition to the JECFA priority list.
Overall, xanthan gum was quite an adventure at Codex, but an adventure that demonstrates the robustness of the Codex processes. Xanthan gum wasn’t approved until after all questions about the safety and technological need were thoroughly evaluated by experts from around the world. The discussion of xanthan gum at Codex stretched over 7 years, required collaboration between both CCNFSDU and CCFA, and even helped with the development of criteria for demonstrating technological need.
ABOUT PAUL HANLON
Paul Hanlon is currently Director of Regulatory Affairs at Abbott Nutrition where he is responsible for a team supporting all aspects of product innovation. As a board-certified toxicologist, Paul leads strategies for gaining approval of novel foods and provides guidance to food safety programs that govern the control of chemical contaminants. He has coordinated the submission of novel food petitions to multiple regulatory agencies and has co-authored a number of papers focused on risk-based processes for controlling chemical contaminants in food. He participates in a number of Codex Alimentarius committees, including the Committee on Contaminants in Foods (CCCF) and the Committee on Food Additives (CCFA), and is the current chair of the Food Safety and Food Additive Working Groups of the International Special Dietary Foods Industries (ISDI).