Food Product Design: Cover - May 2004 - Natural Convenience

May 2004

Natural Convenience

By Lisa KobsContributing Editor

Consumer interest in natural foods doesn't show any signs of slowing just yet -- at least judging by the success of the specialty markets. Whole Foods Market, Austin, TX, the world's largest retailer of natural and organic foods, has 155 stores in North America and Great Britain. Wild Oats Markets, Inc., Boulder, CO, is the nation's second largest natural and organic foods supermarket chain, with 101 stores in 25 states and British Columbia. And natural foods cooperatives continue to thrive around the United States.

The savvy food marketer has finally realized that natural foods aren't a fad movement fueled by aging hippies or a counterculture fringe. Mainstream Americans use natural foods to incorporate health and wellness into their lifestyles -- and spend some serious cash along the way.

The increase in market size and profit potential has prompted a natural foods evolution. These industry changes include "dramatic improvements in taste, quality, packaging and overall marketing," says Bob Burke, principal, Natural Products Consulting, Andover, MA. "Virtually every mainstream category has a natural or organic counterpart. In addition, the price premium is narrowing in most cases, making these items more accessible to more consumers."

The number of products available has increased dramatically, adds Lynea Schultz-Ela, owner, A Natural Resource Consulting, Leander, TX. "The focus categories are frozen foods, especially ethnic entrées, nutrient-dense breakfast cereals, sauces of all types, and meat analogue products in the dairy," she says. "Of critical importance is the inclusion of organic ingredients, reflecting first consumer acceptance, and now consumer demand. More recently we are seeing imported foods play a larger role in the natural-foods market. Specialty foods from around the world are more easily available and are increasingly meeting the American consumer's interpretation of 'natural.'"

And the consumer benefits. "Products are getting better-tasting because of the consolidation occurring in the industry," adds Burke. "You have large mainstream food and beverage companies acquiring smaller natural and organic companies. Kraft, ConAgra, Kellogg's, General Mills, Heinz and many others have made a number of acquisitions of natural and organic companies. When they do, they generally invest in R&D and product development working to improve taste, texture, etc., if the original product had any deficiencies. This raises the bar for the other companies in the category."

But the industry still has a way to go. "Product developers are spending a lot of time and money developing 'me too' products," explains Schultz, "products that replicate what is already on the shelf but with their own brand. It is time to spend money on trend research studying the generationally divided values and demographics of consumers. This would put product developers ahead of the curve designing products that consumers want, rather than products that have minimal improvements over those already available. Specifically, product developers should work hard on enhancing flavors and textures with simple ingredients. Our consumers want to be able to understand the ingredient deck on the products they purchase. Remember, the customer is attracted by the front of the package but they purchase it based on what they read on the back of the package."

Consumer research is an integral part of the development process. Consumers have a range of natural foods perceptions and expectations, and there isn't a one-size-fits-all profile. Subsegments of natural-foods consumers should be targeted appropriately, or at least explored. Maybe one product will satisfy them all, but just guessing can be a costly assumption. The smart developer appreciates the need for examining consumer motivations. Do they want nutrition as well as natural? Should the product be organic? Must ingredients be familiar to the tune of "If I can't pronounce it, I won't eat it?" What does "minimally processed" mean and how is it perceived? Do these opinions change across a product category, e.g., candy versus a frozen entrée? These are important questions to ask up front, not after a line has failed.

Food ingredient suppliers realize the profitability of high-quality, functional, natural ingredients and value-added technical support services to guide the R&D process. While ingredient choices are limited when the entire category of synthetics is removed from the repertoire, plenty of high-quality substitutes make the developer's job a little easier. (Keep in mind that this article focuses on R&D in the United States. The rules regarding natural in other countries may be different and should be researched.)

Naturally sweet Available, easily used and economically priced sweeteners typically aren't an option for use in natural foods. Often, consumers view corn syrup, high-fructose corn syrup, and even sucrose as overly processed ingredients. Sweetening alternatives are available, ingredients that come with a perception of naturalness; however, each comes with its own unique challenges.

Natural sweeteners should be selected by comparing their relative sweetness, flavor profiles, color contributions and functionalities. Each natural sweetener has a different composition of saccharides, and thus a different chemical structure, molecular weight, level of solubility and colligative properties. As such, sweeteners impact body and mouthfeel, viscosity, freezing and boiling points, crystal formation and inhibition, browning reactions, water activity, and hygroscopicity.

Additionally, other parts of a food system (fat content, stabilizers, acid) can modify a sweetener's impact and perception, so these should also be part of the formulation considerations.

Natural sweeteners shouldn't be blended with synthetic or highly processed, "label-unfriendly" ingredients. Liquid syrups, for example, may be extended with corn syrups. Many liquid sweeteners are available in dry granular forms, which are perfect for dry-mix applications. Because of many sweeteners' hygroscopicity, these dried products often contain free-flow agents that may or may not be perceived as natural.

Sucrose. A product designer may need to completely refigure a natural-food system to achieve sensory parity with sucrose, which is usually considered an ideal sweetener. It has a clean flavor and a smooth, level sweetening sensation.

One way around this is to use less-refined sucrose products, like cane juice. "Ten years ago, most cane-based sugar was avoided in favor of alternative sweeteners, such as honey and fruit juice concentrate," says Burke. "Since then, you see less of those, which sometimes were difficult to use, inconsistent, and 'off-tasting' depending on which processed food they were used in."

Mechanically extracted from sugar cane, cane juice is approximately 85% sucrose. Evaporated cane juice is the first crystallized sugar of fresh sugar-cane juice and has about 98% sucrose. These products are less processed than white sugar, have a good consumer image and can be sourced from organic raw ingredients. Naturally occurring molasses gives both a blond color. Granular cane products differ in flavor profile, particle size and color, based on their molasses content. Another less-processed cane product is Sucanat®, a cane juice and molasses granule containing 92% sucrose.

Granular fructose. Consumers accept fructose, which is found naturally in fruit and honey, as a naturally occurring "fruit sugar." However, most commercial fructose is derived from corn processing. This is a far cry from squeezing out fruit's natural sweetness, making fructose a great example of how perception equals reality to consumers.

Fructose is a highly soluble monosaccharide. It provides greater sweetness than sucrose, up to 1.8 times, so less can be used to match sweetness levels. It also has a sweetness synergy with sucrose. Crystalline fructose is available in granular or powdered forms. High-fructose corn syrup does not have fructose's wholesome image and tends not to be used in natural foods.

Honey. This appealing, natural sweetener is mostly fructose and glucose, with less than 10% maltose and minimal amounts of sucrose. On average, honey is 1.0 to 1.5 times sweeter than sucrose, and it also reacts synergistically with sucrose. It is similar to invert sugar and can be used similarly in formulas. Honey has a distinctive flavor based on the source of its nectar and also contributes color. Technical information and conversion factors for using honey in place of other sweeteners can be found at the National Honey Board's website (www.nhb.org).

Maple syrup. Pure maple syrup, the concentrated sap from sugar maple and black maple trees, also has a wholesome image. It's comprised of 90% to 96% sucrose, up to 4% glucose, amino acids, proteins, organic acids, and trace levels of vitamins and minerals. It has a legal requirement in most states of 66?Brix. Its distinct flavor can limit its use, but it often works well in sweetening blends. It's also available dried.

Molasses. The concentrated liquid extract of the sugar-refining process, molasses, can contain up to 70% sucrose and, depending on the grade, is usually slightly less sweet than sucrose. It comes in several grades and a wide range of flavors, colors and consistencies. Its dark color and pungent flavor limit its applications. Additionally, its natural acids may react with parts of a food system that are acid-sensitive, such as leavening.

Invert syrup. In this liquid sweetener, the sucrose has been partially or completely hydrolyzed to form glucose and fructose in equal proportions. Invert syrups are characterized as either fully or partially inverted. Invert sugar is found naturally in fruits and honey, but manufacturers produce an industrial product by cane-juice hydrolysis. Traditional and organic invert syrups are available.

Agave syrup. Extracted from the Mexican blue agave plant, agave syrup, or nectar, is sold at 75?Brix, contains up to 93% fructose and is slightly sweeter than sucrose. Its different grades vary in flavor and color, with the lighter grades being lightest in flavor.

Grain syrups. Corn syrup lacks a natural image, but other grains, such as barley, rice and oats, produce sweeteners that more closely meet consumers' natural expectations. Joe Hickenbottom, vice president, sales and marketing, Malt Products Corporation, Saddle Brook, NJ, explains: "The basic starch hydrolysis of the grains is similar but the processing stages are different since the starches are different. Corn requires much more processing than the others."

Malt syrups, or malt extracts, are derived from germinated barley. Activating the grain's naturally occurring diastase enzymes converts the starch to sweetener. Typically, nondiastatic malt syrups (without active enzymes) are used for sweetening. Malt syrup is mainly composed of maltose, which is less than half as sweet as sucrose. A range of sweetening syrup products -- both liquid and powdered -- exists with varying levels of solids, colors and pH, as well as reducing-sugar levels.

Brown-rice syrup and oat syrup are both hydrolyzed with natural enzymes and can be found as liquids or solids in a range of DE levels. Both benefit from their source grain's wholesome image. They are about half as sweet as sucrose, and both contain naturally occurring flavor and color notes.

Fruit. Juices, concentrates, purées and dried granules, with their naturally occurring fructose, sweeten natural foods and look great on a label. But again, these ingredients vary in their processing and sometimes the result bears little resemblance to the original fruit. Additionally, fruit isn't as economical as corn-based sweeteners. As with all agricultural crops, costs can fluctuate widely.

However, developers get more than just sweetness when working with fruits. Fruit delivers flavor, color, acidity, solids and cellular materials that impact the finished viscosity, pH, aw (water activity) and humectant properties, along with naturally occurring saccharides. Even after purification and decolorization, unwanted flavor components remain, so fruit sweeteners work best in fruit-flavored products or where the fruitiness can be masked. On a positive note, fruits often contribute naturally occurring antioxidants and antimicrobial ingredients.

Single-strength juices are minimally processed, but contain very little fructose and a high percentage of water. For example, one fluid cup of single-strength, unsweetened apple juice (11.5?Brix) has 14 grams of fructose. Concentration by heat or vacuum evaporation yields products with higher solids and more sweetness. Most commercial juice concentrates and purées range from 20 to 70?Brix. Fruit composition is highly variable based on plant source, growing region and level of maturity, so concentrates and purées often require sweetness and flavor standardization by blending several crops together.

Native flavoring On paper, developing a great flavor system looks simple. Just combine the five tastes (sweet, sour, salty, bitter and umami) with the olfactory contribution of flavor and then tack on a flavor potentiator for a little boost. But as any experienced developer knows, it's never that easy. The natural-foods toolbox lacks all of those process-stable, concentrated, flavor-characterizing synthetics. Developing great-tasting, natural flavor systems means using everything you can get your hands on to build rounded, complex nuances.

Flavors are a category where "natural" actually means something -- natural flavors have a legal definition outlined in Title 21 of the Code of Federal Regulations (CFR), Part 101, Section 22 (21 CFR Pt. 101 Sec. 22). "The term natural flavor or natural flavoring means the essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate, or any product of roasting, heating or enzymolysis, which contains the flavoring constituents derived from a spice, fruit or fruit juice, vegetable or vegetable juice, edible yeast, herb, bark, bud, root, leaf or similar plant material, meat, seafood, poultry, eggs, dairy products, or fermentation products thereof, whose significant function in food is flavoring rather than nutritional."

Natural foods benefit from the rich flavors that a home cook would use: herbs and spices, chopped vegetables and vegetable purées, wines and rich stocks. But scientists are one up on the home cook with a world of natural flavors at their fingertips for sweet and savory applications. Natural flavors offer profiles and nuances that can't be achieved by adding ingredients only. Each year, as technologies advance, the tastes of natural flavors improve.

However, natural flavors are plagued with many of the same problems of most natural ingredients. They lack stability during processing and degrade more quickly in the finished product than their artificial counterparts. They're also more costly to produce and not as consistent, and there's always the threat of raw material shortages. But scientists tolerate and solve these problems because there's no two ways about it: Natural flavor looks good on a label and a great-tasting product has an edge over the competition.

As with sweeteners, dried flavors are often combined with other ingredients that should be scrutinized for their label appeal. Encapsulation can build in a degree of stability to natural flavors, but the encapsulate should be made of natural ingredients.

And although they're often more costly than synthetics, natural flavors can actually offer product cost savings. They can replace more-expensive ingredients like fruit purée, or replicate flavors too costly to produce through actual cooking processes, like sautéing, caramelization and roasting.

Flavor enhancers can give a flavor system that extra punch. Sodium chloride (salt) is a great addition to sweet and savory foods. Besides contributing saltiness, sodium chloride rounds out flavors and balances and enhances our perception of most other flavors. And salt isn't just for savory products: Perceived sweetness can be enhanced with low levels of salt. Salt should be solubilized for full functionality.

The amino acid glutamic acid occurs naturally in many foods, but the sodium salt of glutamic acid (monosodium glutamate, or MSG) is a natural foods no-no. Although it's produced by natural fermentation processes, media publicity and its association with "Chinese food syndrome" have left a less-than-positive consumer impression in natural-foods circles.

For MSG-like qualities, developers can substitute label-friendly ingredients that have a high level of naturally occurring glutamic acid. Glutamic acid is the predominant amino acid in soy sauce, so that ingredient can round out flavors and keep the label clean. Soy sauce products are also used for their meaty and hearty flavor alone. Fermented, or brewed, soy sauce is produced through the controlled activity of mold, yeast and lactic-acid bacteria. During fermentation, enzymes break down the proteins in soybeans, and wheat, if used, into amino acids, resulting in hundreds of compounds that contribute to soy sauce's complex flavor and aroma. Chemically hydrolyzed soy sauce does not make the natural cut or provide the same flavor nuances.

Common soy sauce types include fermented tamari and shoyu. They can vary in their strength, flavor profile and color, and are available in liquid and dry forms. Miso paste is another Asian flavor-enhancing fermented-grain product. Mushrooms and tomato paste are other natural sources of glutamic acid.

Other flavor-enhancing ingredients, made from natural processes by some definitions, include hydrolyzed plant and vegetable proteins and autolyzed yeast extracts. These ingredients have a high natural 5'-nucleotide content, which potentiates flavor.

Nature's colors Consumers expect their food to look as good as it tastes, so formulators typically add colorants to most products. Federal regulations direct the use of color ingredients in foods. "FDA links the classification of colorants to whether a colorant requires or does not require certification," says Gabriel Lauro, director, The Natural Color Resource Center, Pomona, CA. Certification applies to the regulatory need to do laboratory analysis to assure the identity and purity of each batch of a colorant produced." In 21 CFR Pt. 73 FDA lists the color additives exempt from certification while 21 CFR Pt. 74 lists the color additives subject to certification. Certified colors are synthetic and are not options for natural foods. The noncertified, or exempt, colors are the ones usually thought of as natural.

Developers should note that not all noncertified colorants are naturally derived. Most beta carotene, for example, is made synthetically. Additionally, many coloring agents from natural sources are altered or processed and synthetically preserved. "Many of the color additives exempt from certification cannot be used without alteration or preservation," says Sue Ann McAvoy, manager, regulatory compliance, Sensient Colors, Milwaukee, WI. "Beet juice, fruit juices and vegetable juices that are expressed from fruits and vegetables are sometimes preserved or acidified to maintain color. The preservatives or the acids are considered incidental additives per the incidental additive definition" of 21 CFR Pt. 101 Sec. 10. "They do not have to be declared if they meet the requirements of this section, unless they are potential allergens (i.e., soy lecithin). These type of ingredients are allowed to be used in exempt colors either by the regulation in the definition of the color in Section 73, or because they are GRAS.

"Most emulsifiers fall under the definition of an incidental additive," she adds. "They would not have to be labeled, unless specifically required by their CFR listing or if they did have a 'technical or functional effect' ... in the finished food. Color additives extracted with solvents are still considered as natural by the color industry. FDA has set limits on the amount of solvent that can remain in the product. Again, some products, such as paprika oleoresin, turmeric oleoresin and some of forms of annatto, cannot be obtained without solvents. The use of solvents is part of the definition of these products, and the residual solvents do not have to be declared."

While developers may separate coloring agents into natural and artificial, FDA doesn't. "The FDA does not recognize any colorant as natural unless it is derived from the characterizing food," says Lauro, noting that 21 CFR Pt. 73 reads, "Food ingredients, such as cherries, green or red peppers, chocolate, and orange juice, which contribute their own natural color when mixed with other foods are not regarded as color additives; but where a food substance, such as beet juice, is deliberately used as a color, as in pink lemonade, it is a color additive."

But consumers don't care about regulatory compliance; they care about how a product looks. "The most difficult aspect of the application of natural colorants is attainment of a satisfactory hue," adds Lauro. "When compared to the synthetic colorant, the natural colorants are often dull, pastel and, with a few exceptions, lack the luster of synthetics. The consumer's mental acceptance target is what he or she has been exposed to from birth, mainly products brightly colored with synthetic colorants. Replacing synthetics with natural is a real challenge, especially when the target is firmly entrenched. An even more serious problem is the lack of a complete natural color palette. There is no FDA-approved blue or green chromaphore. The absence of a primary color, blue, frustrates achieving a rainbow of hues."

Once a color is selected, it has to work within the designated food system. "The application of natural colorants requires trying to achieve compatibility between the chemistry of the chromaphore with the properties of the food, its process and distribution parameters," says McAvoy. "One does not have many choices when selecting for a specific hue. Having identified the possible chromaphores that may achieve the target hue, one has to turn attention to such questions as: Is the colorant to be in a liquid or powder form? Be water or oil soluble? Be affected by pH? Be affected by the expected conditions of processing? Be affected by light (should the product be distributed in a clear package)? Meet religious requirements? Have the potential of achieving storage life needs? Etc."

With some clever blending and the help of a good coloring house, some very beautiful colors from naturally occurring sources can be made. Natural yellows and oranges can be achieved from turmeric, annatto, paprika and beta carotene. Magenta and violet come from fruit juices like elderberry, blackberry and aronia (black chokeberry), and vegetable juices, such as red cabbage and black carrot. Reds are derived from beet-juice and carmine. Dark-brown comes from caramel color, but its "naturalness" is debated, as it is a reaction product derived from a heat process of selected carbohydrates. (For more detailed information on natural colorant usage, see Food Product Design, August 2002, "Color Naturally," and March 1994, "Natural Food Colors.")

Besides looks, consumers care about what's on the label. According to Lauro: "Many companies in the United States value the importance to the consumer of a naturally derived colorant and will declare the colorant by name in the ingredient statement. Some even go as far as placing a parenthetical statement 'a natural color' after the colorant's name. This does double duty by clarifying the colorant for the consumer and placing emphasis on its 'natural' status, even though there is no legal definition for 'natural' colorants. Some manufacturers avoid the problem altogether by identifying the color additive (not requiring certification) as 'color added' in the ingredient statement."

Keep it stable Stabilizers are another powerful set of instruments in the hands of a good developer. A wide variety of ingredients have stabilizing capabilities, including starches, hydrocolloids, proteins and emulsifiers. Again, the level and type of processing garners whether or not any particular ingredient fits a natural application.

Starch. Modified food starches are the product developer's workhorses. Scientists depend on them, yet take for granted the ease with which they build viscosity and texture, bind moisture, form gels and films, improve heat and freeze/thaw stability, encapsulate, aerate, etc. But these functionalities result from means that are not welcome in the world of natural. Cross-linking, oxidizing, substituting and esterification are just some of the chemical processes that increase starch's resistance to acid, heat, shear, and freeze/thaw cycles. But with natural foods, chemically modified starches are out and natives are in.

Native, or unmodified, starches are raw starches isolated and dried from natural grain or tuber sources. Native starches come from a variety of grain sources, including corn (dent and waxy), tapioca, wheat, arrowroot, potato and rice. Because they are not chemically altered, label-friendly native starches can be listed as their generic source starch, e.g., corn starch.

Functionally, native starches do not always match their chemically modified counterparts one to one. "Native starches do not have superior processing stability, especially in high-heat and/or high-shear environments and, therefore, may perform at lower expectations than would a modified starch," says Elizabeth Lenihan, food technologist, Tate & Lyle North America (A.E. Staley Manufacturing Co.), Decatur, IL. "The largest applications for native starches are as cost-effective thickeners and moisture scavengers in products, such as dry-mix soups, gravies and sauces, designed to be immediately consumed. Stove-top cooking is not particularly harsh so native starches may survive the cooking process."

Gil Bakal, managing director, A&B Ingredients, Inc., Fairfield, NJ, adds, "All native starches require additional care during processing to ensure that the starches are not destroyed during processing."

One way to maximize native starch's functionality is to look for synergies with other stabilizing ingredients. "When developing natural food applications it is important to be open to combinations of natural ingredients to help achieve the desired texture," says Bakal. "For instance, waxy rice starches work exceptionally well with iota carrageenans in helping achieve higher viscosity levels. Very small amounts of the carrageenan can extend the functionality of the starch dramatically. Combinations of starches are also important when trying to develop the right texture and rheological profile."

As with all starches, native starches exhibit differing functionalities depending on their source grain. This is especially important with native starches that have not had the benefit of chemical modification. "Native waxy starch is often used as a fill aid for canned soups and stews," says Lenihan. "It develops high viscosity preretort for even particulate suspension, then breaks down and loses viscosity during retort. Waxy starch is also used to impart a longer texture in, for example, cheese sauce, where a long, stringy texture is desired. Native dent corn starch contains amylose and will impart a shorter, or even a gelled texture where desired. Tapioca starch will have a long texture when hot, but set back to a soft gel on cooling."

Another development option is to use specialty native starches that are physically altered in proprietary processes that expand functionality. They're available in cook-up, instant and cold-water-swelling forms. These altered starches deliver performance characteristics more typically found in modified starches. "With modified starches, syneresis and retrogradation are usually not as much of an issue because they have been compensated for through chemical modification," says Bakal. "We have one waxy rice starch called Remyline XS, which was developed to act like a modified rice starch without using any chemical modification. This is done by making the starch granule more rigid, which means it will be more stable during process stress."

A small number of native specialty starches show greater resistance to harsh environments like acid, heat and shear and can also better withstand freeze/thaw cycles. But their use is limited to cases where the starch's characteristics (texture, length, gelling, etc.) happen to match the specific properties the developer desires.

Hydrocolloids. Gums are a natural way to build texture and product stability. With an ability to bind as much as 100 times their weight in water, gums deliver excellent thickening and gelling capabilities. As such, they perform many secondary functions, including binding, ice-crystal inhibition, emulsification, film-forming, stabilizing and syneresis prevention. But hydrocolloids get mixed reviews from consumers and, natural as they may be, the names can be off-putting. Remember that old commercial where the boy reads off the list of stabilizers from a carton of ice cream? The look on his face says it all!

There's an abundance of gums to choose from with multiple functional characteristics. Exudate products include gum arabic (gum acacia), gum ghatti, gum karaya, and gum tragacanth. Hydrocolloids can also be extracted from plant and animal sources, such as agar, alginates, carrageenan, pectin and gelatin. Flour-source products, derived from plant seeds, cereals and plant tubers, include locust-bean gum, guar gum, tara gum, and konjac flour. Fermentation produces xanthan and gellan gums. Most hydrocolloid suppliers produce functional blends for specific applications and product characteristics. Sourcing can be an issue with some hydrocolloids. Political unrest in countries of origin can make a consistent supply quite variable and costly.

Not all hydrocolloids are natural, such as the cellulose derivatives carboxymethylcellulose (CMC), methylcellulose (MC), and hydroxypropyl methylcellulose (HPMC). Also, keep in mind that naturally sourced gums can be further chemically modified and vary in their level of naturalness.

Emulsifiers. The list of emulsifiers for natural applications is a relatively short one. Most of the ingredients for holding immiscible substances together are chemically derived. Probably the most-natural emulsifier is egg yolk. It contains surface-active properties of phospholipids and lipoproteins, which support emulsification. But yolk comes with more than just these surfactants (e.g., pigments, fats, flavor) so product designers need to ensure these characteristics are acceptable as they are in eggs' typical applications: mayonnaise, salad dressings and bakery products.

Plant lecithins offer greater functionality as emulsifiers with a natural image. While they can be sourced from rice, corn, and rapeseed, soy lecithin dominates the market in the United States. Soy lecithin is a complex mixture of phospholipids, glycolipids, triglycerides, sterols and small quantities of fatty acids, carbohydrates and sphingolipids. Lecithin is water-extracted from vegetable oils and the unbleached, unmodified forms are well-suited to natural foods. To improve its functionality, however, lecithin is usually chemically modified by processes such as hydroxylation and acetylation. These lecithin products would be off-limits for natural foods. Lecithin is a GRAS ingredient.

Lecithin possesses both positive and negative charges and it's characterized by its HLB (hydrophilic-lipophilic balance) range. This represents a balance between the size and strength of the hydrophilic and lipophilic emulsifier groups. The HLB numbers form a scale from 1 to 20. On the low end are emulsifiers with a greater affinity for oil; on the high end are those attracted to water. Chemically modified lecithins have a wider HLB range than unmodified lecithin.

The presence of other stabilizing ingredients may reduce the amount of lecithin needed to create an emulsion. Proteins also have emulsification capabilities. When a surface-active protein molecule is adsorbed at an interface, the polar amino acids orient to the water phase while the nonpolar amino acids orient toward the lipid. Whey, casein and soy proteins offer emulsification capabilities.

Many thickeners double as emulsifiers. While they have little or no effect on interfacial tension, they hold oil in suspension, reducing the potential for coalescence.

Fat of the land A good understanding of lipid chemistry and the functional characteristics of fats and oils, as well as lipid processing techniques, will benefit anyone developing a product, natural or not. Additionally, development teams need to identify lipid-related finished-product and production needs early on in the process.

Vegetable oils dominate in the world of natural foods. Olive, soybean, sunflower, safflower, cottonseed and canola oils enhance foods without causing any labeling woes. The most natural form of vegetable oil is expeller-pressed, a mechanical-pressure process that removes oil from seeds. However, most commercial oils use solvent extraction and additional refining processes, including neutralization, bleaching and deodorization.

One solvent-free line of soybean oils called Nexsoy® is produced by Endura Products, L.L.C., Springfield, IL. These oils are expeller-pressed and physically processed from non-GMO, identity-preserved soybeans. "Most oil commodities for food manufacturing applications utilize solvent extraction because it's a very efficient way to remove oil," explains Rob Kirby, vice president, marketing. "But chemicals like hexane that are used in the extraction process degrade the quality of the oil. With expeller pressing and physical processing, however, no chemicals are used so you get all-natural oil."

Unsaturated vegetable oils benefit from the antioxidant activity of naturally mixed tocopherols, a form of vitamin E, or natural spice extractives from herbs, such as rosemary or oregano. Antioxidants should be added into foods as early in the process as possible to guard against oxidation that may develop during manufacturing.

Domestic vegetable oils are not always an option, depending on economic and functional factors. Liquid oils generally are susceptible to attack by atmospheric oxygen, resulting in rancidity, and they do not offer the plasticity of hard fats. And while scientific advances such as chemical processing and hydrogenation for added functionality and increased shelf life have solved many of vegetable oil's shortcomings, such processes aren't an option for natural foods.

Instead, stable and functional natural tropical oils are back in style. For many years, tropically sourced oils like palm, palm kernel and coconut oil have come under fire for being highly saturated. Today, they are seen as a solution to the problem of hydrogenation. "Marketing can make a product look bad and that's what happened to palm oil," said Pam Ish, customer service supervisor, Spectrum Ingredients, Petaluma, CA. "But palm oil is a great substitution for hydrogenated fats."

Palm and palm kernel oil are actually two separate lipid products produced from the same plant, the African, or oil, palm tree (Elaeis guinnesis). Palm is the less saturated of the two with a fatty-acid profile that's 40% monounsaturated, 10% polyunsaturated and 50% saturated.

Palm oil can be obtained without solvent extraction and it's available as a liquid or plastic at room temperature. Its oxidative stability makes palm oil a good frying oil. It also has a tendency to crystallize into small beta-prime crystals, which increase its creaming performance in baked goods. Palm blends can be designed for specific functional characteristics.

Animal fats have carried a less-than-healthful image so they no longer are as common as vegetable oils. But animal fats, like tallow and chicken fat, contribute rich flavor and saturated-fat stability. Look for animal-fat sources that are preserved by freezing or natural antioxidants.

Butter wears a wholesome image and can even be tailored for specific functional applications. The Wisconsin Center for Dairy Research, Madison, has developed a process called dry crystallization that separates milk fat into fractions. These are recombined to make different types of butter products with varying physical properties and high-quality butter flavor.

A word on preservatives Bacteria, yeast and molds are the natural food's nemesis. Lowering aw with sugars, salts and other solids is a natural, preservative-free technique for extending shelf life, but it's not always applicable or possible.

One natural preservation method is to lower a food's pH with organic acids. In a high-acid environment (in foods, a pH below 4.5 is considered acidic), many microorganisms will not proliferate. Organic acids may be found naturally in foods or can be added as ingredients. Citric acid is a good, all-purpose acidulant; acetic, benzoic, lactic, malic, propionic and sorbic acids can also be added to balance tartness. Acidulants are generally labeled by name, e.g., "citric acid."

When added as a noncharacterizing ingredient, cranberries, dried plums and raisins can serve as effective antimicrobials. Some spices also have antimicrobial activity, including garlic, onion, cinnamon, cloves, thyme and sage. However, their flavor may prevent usage levels high enough to prevent spoilage.

Some preservatives, although natural, are not label friendly. Potassium sorbate, a naturally occurring organic acid, or preservatives like nisin and natamycin, derived from fermentation, may be natural, but their names have "chemical" connotations that may not resonate with avid label readers.

With few regulations to back it up, much natural product development is based on common sense. Ultimately, it's the developer's responsibility to keep things on the natural up-and-up by asking questions about ingredients and their processing methods.

Lisa Kobs is a Minneapolis-based food scientist and technical writer focusing on new-product development. She has an M.S. in Food Science from the University of Wisconsin-Stout, Menomonie, and enjoys healthy cooking and finding new ways to promote good nutrition.

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