Nutrients in the Mix

The increasing demand for healthy foods means more and more products require formulation with increasing numbers of nutrients. Characteristics of individual nutrients, and the frequent desire for multiple nutrients, require that developers create complex blends known as “nutrient premixes.”

Addition of vitamins began with “enrichment,” replacement of nutrients reduced or destroyed during processing. Flour, for example, is enriched with iron, riboflavin, thiamin and niacin, which are lost in milling. Current development in the global nutrition industry, however, lies in “fortification,” the addition of nutrients above levels typically or naturally found in a food.

Formulating with the wide array of nutrients in demand is no simple task. “Companies that are not fluent in nutrient sources and activities can rely on premixes to deliver a custom nutrient package tailored to their product,” says Alice L. Wilkinson, director of product development, nutritional ingredient division, Watson Inc., West Haven, CT.

Made to order 

Tailoring a nutrient blend is crucial to virtually any new product. Ram Chaudhari, Ph.D., senior executive vice president, chief scientific officer, Fortitech, Inc., Schenectady, NY, recognizes some of the considerations that must be made when formulating with vitamins: “When more than one nutrient is being added to fortify food and/or beverage products, a formulation scientist must consider interactions, both positive and negative, which could take place. Vitamin C, for example, has been shown to improve bioavailability of iron. Iron and other trace minerals have, on the other hand, been shown to facilitate oxidation of vitamin C under certain circumstances.”

Certain interactions become more significant under different processing parameters. For example, “In solutions of the B vitamins, riboflavin can cause the oxidation and consequent loss of thiamin,” Chaudhari notes. “If ascorbic acid is included in the solution, a reaction does not occur. This observation is of practical significance in cases where solutions of water-soluble vitamins are sprayed on foods during the fortification process.”

In addition to adverse interactions, addition of vitamins and other nutrients poses logistical concerns. Nutrients used at very low levels are susceptible to errors in batching and inadequate mixing and dispersion. By transforming multiple ingredients into one, human variability is eliminated and thorough homogenization of the final product is less difficult to achieve.

Calling upon premix manufacturers’ expertise, developers can quickly obtain blends that serve a particular market segment, such as athletes, children, women, senior citizens, even pets. Similarly, blends can target specific health conditions.

Nutrient experts agree that while new application areas continue to develop, beverages and bars are the most-common and most rapidly growing areas. “Customized blends may contain a selection of vitamins, minerals, amino acids, nucleotides, nutraceuticals and other functional ingredients applicable to a wide range of foods, including baby formulas, cereals, medical foods, soups, flour, nutrition bars, dairy products, sports drinks, juices, water, snacks, candies, supplements, spreads, baked goods and more,” Chaudhari says.

Despite growing demand for a number of nutrients, Wilkinson says certain combinations are commonly requested, including “the energy blend—typically with added ingredients such as taurine and guarana, as well as a complement of vitamins and minerals. The B-complex is also associated with energy and increased metabolism. An antioxidant blend that may include vitamins A, C and E is also popular.” Market-trend information also indicates growing popularity of other nutritional ingredients, including calcium, omega-3s, sterols, polyphenols, coenzyme Q10 (CoQ10), prebiotics and other functional food ingredients.

It is this variety of ingredients, their physical and chemical characteristics and interactions, that create the many challenges faced by premix manufacturers.

Shaken, not stirred 

Typical premixes may contain 10 to 20 active nutrients, in addition to three to six functional ingredients. Some may be composed of as many as 30 actives and carriers. However, the blending and processing techniques result in the production of a reliable, high quality, homogenous, shelf-stable product vs. a product that is inconsistent and likely to cause regulatory issues or recall situations.

To comprehend the challenges when producing a homogeneous, correctly proportioned blend of these active ingredients, Chaudhari offers the following analogy: “Imagine trying to create a uniform blend of one spoonful of granular sugar, three spoonfuls of flour and five spoonfuls of rice. Then add to that blend a 1/2 teaspoon of salt and a 1/4 spoonful of color.”

Formulating a premix also requires consideration of the product to which the blend will be added, and the addition methods that will be used. Clear, ready-to-drink (RTD) beverages require a soluble ingredient that will not settle out. Soluble nutrients, however, do lend greater impact on finished product flavor and color. Greater solubility can also come at the cost of nutrient concentration. Calcium gluconate is 8.94% calcium, requiring 1,120 mg to provide 10% of the daily value (DV) of calcium. Achieving 10% DV for calcium as calcium lactate requires 746 mg, and as calcium carbonate requires 250 mg.

Dispersion of less-soluble minerals can be improved by reducing the particle size. “For dairy-based or shake-before-use formulates,” notes Wilkinson, “we will typically incorporate the macro minerals—calcium, magnesium, phosphorus and potassium —as micronized versions.” Typically, less soluble sources are preferred, as they can carry counter ions. “Dicalcium phosphate could help meet other label claims,” she says “and being less soluble, create fewer issues in regards to changes in taste, color and pH.”

Encapsulated audience 

Spray-drying is a basic form of encapsulation where a fluid material is mixed with a carrier and atomized into a chamber with hot air currents, encasing the fluid within the carrier. When you take an oil-based vitamin and spray-dry it with a modified starch, the liquid material is transformed into a dry powder. A mix could be encapsulated for processing assistance, or individual components might be encapsulated to protect it from other components of the mix (or the mix from the encapsulate). Selection of the appropriate carrier depends on the final application.

A cold-water-dispersible (CWD) beverage would call for a more-soluble carrier than would a tablet or bar. And while addition of beta-carotene typically imparts a yellow tint to products, variations to spray-drying technique and carrier can yield vitamin A products that provide varying degrees of clarity.

Sensitive ingredients may also be coated with a material to protect or control the substrate’s interaction in the finished product. Lipid encapsulation improves stability of heat- and oxygen-sensitive vitamins, while decreasing mineral reactivity. Lipid coating decreases vitamin reactivity with minerals and other ingredients in an instant hot cereal. Creating a more heat-stable coating for vitamin C with lipids will protect the vitamin for a baked-bar-type application.

Considering use of a lipid encapsulate should include several processing factors. Very high-temperature processing can soften or melt a lipid coating, resulting in unwanted interactions. Particle size of the coated materials may increase beyond the limits of systems that include sieves or screens. High shear may damage the encapsulate coating. Labeling needs should also be considered, as some encapsulation materials may not qualify as “natural,” “non-GMO,” or “kosher.” 

Old dogs, new mix 

Advances in blending and encapsulation technology continually create new opportunities for premixes. Bill Murphy, director, premix business unit, LycoRed, Orange, NJ, describes an innovative blending technology that gently increases homogeneity, stability and functionality. “Premixes for cereals can be added prior to extrusion, because the microencapsulated nutrients survive the heat and pressure of manufacturing,” he says. This eliminates the need for post-extrusion applications that can necessitate large overages and additional expense.

As consumer awareness increases, so grows demand for foods packed with vitamins, minerals, antioxidants and more. Manufacturers are capitalizing on scientific advances revealing how certain food components can delay the onset of diseases such as cancer, osteoporosis and diabetes, as well as assist an aging population with ailments and lifestyle issues.

In the dynamic nutrient industry, nutrient premixes are like a puzzle; a mixed up bag of pieces, assembled by experts, to reveal a picture of improved health.

R.J. Foster, with over a decade of experience in research & development and technical service to the food industry, is a processing consultant, specializing technical communications. He can be reached at [email protected].