Kathie L. Wrick, PhD, RD, Partner, The Food Group

Packaged food companies in the U.S. have been actively, though quietly, working on sodium reduction for quite some time. On their websites, many large firms, such as Nestle and Unilever, have publicly committed to reducing salt and sodium in their products. Others have quietly addressed this issue over time, product by product, and continue their efforts to produce lower-sodium foods their consumers will enjoy.  Some companies are in the process of making near “across-the-board” sodium reductions using gradual, and sometimes nearly imperceptible, reductions in sodium-containing ingredients, as well as their own scientific advances in sodium-reduction approaches that can lead to proprietary technologies.

Lucinda Wisniewski, vice president, Innovation Group for The National Food Labs, indicated that industry requests for sodium-reduction programs to her company peaked about a year or so ago and have declined since. “Many companies have done a lot to reduce sodium as far as technology allows them to, and they have boosted overall flavor, often utilizing culinary techniques.” She and Bob Earl, vice president of Scientific Affairs at the Grocery Manufacturers Association (GMA), the parent organization of the National Food Lab, together believe that, overall, the development phase of sodium reduction may have run its course for the time being, and the new or reformulated products are being introduced now.

“Further sodium reduction is likely to remain an ‘eternal quest,’” says Wisniewski, in light of the sizable disparity from what people actually eat compared with the much lower amounts now encouraged by health authorities. In fact, the American Heart Association has asked both the FDA and the 2010 Dietary Guidelines Committee to reduce dietary sodium recommendations even further, down from the current 2300mg/day in a stepwise fashion, to 2,000mg/day by 2013 and, ultimately, to 1500mg/day by 2020 (source: Letter from Timothy J. Garner, MD, president of AHA to the co-executive secretaries for DGAC 2010, January 23, 2009; http://www.americanheart.org/presenter.jhtml?identifier=3066274). If the guidelines are indeed lowered, the quest for further sodium reduction will be revisited

“Though the technology has gone about as far as it can, major firms have quietly gone about reducing sodium with little fanfare. New products are being introduced now that capitalize on the intensive reformulation efforts of the past year or so,” says Bob Earl of GMA. “People don’t realize what an ongoing process sodium reduction has been,” he explains. The table below was compiled from historical documents by Earl and his GMA colleague Regina Hildwine, and it demonstrates that many everyday foods are now considerably lower in sodium than they were a generation ago.

New Technology Developments
Food companies are also investing in new proprietary technologies for flavor enhancement and sodium reduction through technology partnerships with suppliers. One such supplier has discovered or in-licensed many of the key receptors inside the taste bud cells that mediate the five basic tastes in humans. Having isolated and rearranged human taste receptors into what might be called an “artificial taste bud,” it has created a proprietary receptor-based assay system that provides a biochemical or electronic readout when a test compound affects the receptor. A robot-controlled automated system is in place to enable faster compound discovery.

The system integrates receptor-based screening assays with plates containing an array of individual fluid wells, each of which can screen a different compound. This discovery and development process has enabled the supplier to find novel flavor enhancers and taste modulators over the entire range of basic tastes much more effectively than using the traditional method of simple taste tests. It now has a library of hundreds of unique candidate flavor enhancers and taste modulators. Some have been sufficiently developed for use in food product formulation and are now used in food products sold at retail.  These ingredients are developed in collaboration with and for the exclusive use of their research partners, which currently include Nestle, Cadbury-Schweppes, Ajinomoto, Campbell’s, Coca-Cola and Kraft.

One research company has identified some candidate compounds that prolong the opening of the sodium channel but are not yet effective in a food system and require optimization before they can be used as a product development tool.

It is a fact that low-sodium diets will cause the consumer desire for salt to shift downward. After two to three months on such a regimen, consumers appear to adapt psychologically, and any return to the “old” levels of salt intake will register as too salty. It is not yet known if the physiologic process of tasting salt is influenced by diet, but the current hypothesis is that it does not. Attempting to lower sodium intake is the hardest part of making this change, and food processors are well aware of this issue.

However, a behavioral approach to reducing salt intake rather than trying to fool humans’ sensory mechanisms may be the most effective way to bring sodium-consumption levels down to closer to what our bodies require. Human evolution has not yet responded to the problems associated with excess sodium consumption and hypertension. The species has certainly shown no signs that the ability to taste salt is changing such that they desire less of it. Sensory scientists have shown experimentally that a preference for salt begins to develop around the age of 4-6 months. One interpretation for this observation is the maturation process of sensory capabilities begins at this age. Another is that this age begins the vulnerable period where humans become sensitive to “liking” salt in higher concentrations than needed. More time and research is needed to find out which line of thinking will prevail.

Other Web Resources
ConAgra to Reduce Sodium by 20% by 2015
Old Salts
Expanded Benefits of Salt Reduction
GMA and Sodium

From the February 15, 2010, Prepared Foods E-dition