Editor’s Note: This article originally appeared in Prepared Foods magazine, a sister publication of The National Provisioner at BNP Media. For more on phosphates in other food products, and for stories like this one, visit www.preparedfoods.com.

As “clean label” moves from trend to standard, consumers want ingredient transparency, trust, and product understanding. Clean label creates cost, stability, and sensory challenges for food and beverage manufacturers, especially since there currently is no clear definition.

Consumer researcher NPD Group reports that the top consumer trend of 2016 focuses on the desire for consumers to eat “real” and “natural” foods and beverages. According to the 2015 Deloitte Food Value Equation Survey, by Deloitte Touche Tohmatsu Ltd., consumers are “making purchase decisions based on evolving value drivers.” Such evolving drivers have always been present in the minds of consumers but more than half of consumers surveyed report that they value concerns of health, wellness, and transparency. This also is coupled with a nearly as consistent demand for quality, competitive prices, and nutritionally sound products

Phosphates added to foods and drinks fall into a consumer perception gray area. As an additive, in certain products, phosphates on the label might generate questions from consumers. But, equally, there are applications for phosphates that deliver nutritional benefit to consumers that can override any such concerns.

Among retailers and manufacturers embracing clean label ingredients, however, some are adopting stricter lists of “undesirable” or “no-no” ingredients and some phosphates appear on these lists. Since the definition of a “clean label” has yet to be fixed, these lists vary from source to source.

Phosphate ingredients can be used to create a nutrition facts panel with increased positive or reduced negative healthy components. Phosphates are allowed in some organic labeled products that are not labeled as 100% organic. For example, certain phosphates are allowed for specific applications or functions. (For the US, organic allowances are listed in the USDA National Organic Program Code of Federal Regulations Title 7: Agriculture; Chapter 1; Subchapter M; Part 205.) In general, phosphates are not considered to be “natural.”

Phosphates au natural

Combinations of phosphoric acid with alkali sources or inorganic elements, creates a family of salts that are collectively called phosphates. Phosphates are not only indispensable for the growth of plants, they are an essential mineral for human life. Coupled with calcium, phosphate is essential for bone health. Beyond bones, phosphates are critical to maintaining the pH of blood and the function of virtually every metabolic system.

Through adenosine triphosphate (ATP), phosphate is part of the key building block of cellular energy in the body. Phosphate is widely found in food, and most phosphates in the diet come from dairy products, meats, seeds and legumes.

The basis for all phosphates is phosphoric acid, a phosphorus atom with four oxygens bound to it. These phosphoric acid molecules can form salts in the ortho form when combined with sources of sodium, potassium, calcium, magnesium and ammonia. The salts can be condensed into chains of pyro-(2), tri- (3) tetra- (4), penta- (5) and longer chains of phosphate monomers.

The longer polyphosphates are commonly referred to as hexametaphosphate, a linear, long chain of phosphate monomers having an average chain length from 5 to 30 units. The cation as well as the anion form, mono-, di-, and tri-phosphate define the functional characteristic of each salt.

Each phosphate has a unique solubility and pH once dissolved into water. Coupled with exceptional protein interaction and hydration properties, buffering capacity, and pH modifying properties, this multifunctional ingredient class also provides a chelation capacity.

Depending on phosphate chain length, phosphates can sequester or chelate metal cations – a function that can prevent metal (iron, zinc, magnesium, calcium, and copper) catalyzed lipid oxidation, contribute to food safety and protect a functional protein from inactivation due to calcium binding.

Flavor and function

In foods, phosphate salts have the capability to stabilize flavor by inhibiting oxidation and warmed over flavors. Generally either tripolyphosphate or pyrophosphate is used to interact with iron and copper, key oxidation accelerants. Preventing oxidations avoids rancid flavors in baked goods, meat, seafood, poultry as well as dairy applications.

For every food product, the phosphates provide multiple functionalities. In meat poultry and seafood applications, the phosphates have a unique capability of interacting with the myofibril proteins to help hold and retain moisture. This reduces purge during storage and cooking, and enhances juiciness and desired mouthfeel in cooked meat products.

Phosphates, particularly the pyro- or diphosphates have the ability to extract the myofibril proteins responsible for emulsification (ex. hot dogs) and binding whole-muscle pieces (ex. boneless hams, turkey deli loaves, etc.) together.

In the case of ground and comminuted products, phosphates can be added into the formulation during the blending step. For whole-muscle animal proteins, phosphates can be applied by brining, injection, or surface coating by dip or spray.

For meat and poultry applications, many countries establish an upper limit for the concentration of phosphates. For Canada and the U.S., this is set at a maximum concentration of 0.5% within meat products. In Canada this regulation is complex, as the 0.5% figure is based on disodium phosphate equivalent weight. While in the U.S., the 0.5% regulation is based on total added phosphate. For Canadian users of phosphates and phosphate blends, this means a conversion calculation is required when phosphate is being used.

Phosphate solutions

Phosphate salts can be made into a solution prior to blending or injecting into a formulation. Certain phosphate salts can be successfully added to meat in dry form. Many phosphate suppliers have proprietary phosphate premixes designed for various applications and process conditions.

For animal protein applications, phosphate blends have been developed to account for the inherent variation in muscle quality as well as the processes involved in producing a quality product.

Such processes include injection, marination, vacuum tumbling, chopping, forming, and cooking. Selecting the correct phosphate for formulation is dependent on these wide ranging variables, and as such, it is worth setting a strong experimental design to evaluate the impact of various phosphates on formulation or consult with an industry expert.

Making phosphates fit

Food phosphates are commonly pooled into a single category, but as a class of ingredients, each form of phosphate has unique and specific characteristics that determine their suitability to an application. It is important to focus on the food functionality and processing characteristics prior to selection of a specific phosphate.

Different phosphates will perform differently under various pH and salt conditions. When formulating with phosphates in food products such as meats, where phosphate content is regulated, it is critical to select the phosphate based on the appropriate solubility, pH, and diphosphate content to achieve the desired outcome. Ingredient suppliers typically will work with processors and formulators to pinpoint the precise form of phosphate for a food or beverage formulation.

One current issue impacting phosphate selection is global health initiatives for sodium reduction. While the push for sodium reduction in processed foods is controversial, consumer health organization demand for healthy foods and beverages drives focus on this initiative. Given that many countries are now legislating or setting voluntary guidelines for the reduction of sodium in food products, phosphates need to be part of the strategy for sodium reduction.

In certain formulations, potassium or calcium phosphates can act as substitutes for sodium phosphates. Consideration should be given to level and allowances. The functionality and conversion ratio for regulation may not be identical.

Formulation work will be needed to achieve equivalent flavor, texture and shelf life. In general, phosphates alone cannot be the focus, but NaCl (table salt) and other strategies, flavor enhancers and maskers must be considered to achieve targets in sodium reduction and food quality.

One clean-label strategy in meats is switching to starch. The elimination of the phosphate can be complicated if the product is injected, tumbled or brined. Soluble phosphates are able to migrate into whole-muscle meat more readily than starches.

In the case of injected meat, starches can cause a “tiger stripe” effect in the meat, if not properly tumbled to redistribute the starch. Unlike the diphosphate, which directly interacts with the muscle protein causing the protein to bind water, starches do not interact with the actual protein, but do bind moisture.

In certain whole-muscle products, starch is considered filler, and could impact labeling requirements in standardized meat products. Equally, fibers from sources such as citrus, celery, and pea, as well as certain alginates, all have been promoted as non-phosphate moisture retainers for meat products. Processors must be aware of the regulatory approval for inclusion of fiber sources into meat, as these ingredients could be classed as fillers.

Manufacturers will face the dilemma of clean and natural labeling versus the wide ranging functionality of phosphates in foods. Natural sources of functional phosphates have yet to be identified. Even once found, there are regulatory and labeling considerations, such as the case with celery extract as a “natural” alternative to addition of nitrites and nitrates.

The challenge with phosphates is the fact that they are multifunctional. So, although ingredient manufacturers have identified alternate emulsifiers, moisture retention, and fortification ingredients to clean up the label of products that traditionally would have included phosphates, often it takes more ingredients than a single phosphate ingredient.

While consumer demand will dictate any eventual changes to the use of phosphates in manufactured products, ingredient makers and suppliers continue to provide systems that deliver broad functions in food manufacturing. NP

Editor’s Note: This article originally appeared in Prepared Foods magazine, a sister publication of The National Provisioner at BNP Media. For more on phosphates in other food products, and for stories like this one, visit www.preparedfoods.com.