The Use of Nutritive Sweeteners
in Organic Food Processing Operations

By Cheryl R. Mitchell, Ph.D.


Nutritive sweeteners are the backbone of most food formulations, from baked goods to beverages. They are responsible for the bulk of the food product and usually are the first or second ingredient listed on the label. As such, the choice in sweetener affects not only the taste, appearance and functionality of the product, but also the successful manufacturing and marketing of the product. The growing organic industry has caused an increase in production of more and more diversified organic sweetener ingredient products to meet the needs of organic food product manufacturers. During the past 20 years, a variety of organic sweetener ingredient products have become available on an industrial scale. However, in order to select the right sweetener, it is important to have an understanding of the availability, composition and metabolic benefits of these sweetener ingredient products.

When considering the availability of organic sweeteners, it is essential to understand the source, supplier and pricing. The composition of the sweetener dictates the form of the sweetener (liquid or solid), as well as the functionality and consequently, the performance of the sweetener in imparting sweetness, flavor, mouthfeel and texture in the product. The metabolic benefit of the sweetener is dictated by both sweetener composition and source. For example, products that are designed for providing long-term energy, or that are well tolerated by diabetics, would utilize sweeteners having a different composition than those products providing quick energy. Products that are designed for specialty markets, such as infants, elderly or allergen-sensitive consumers, would pay special attention to the source of the sweetener. These features of availability, composition, and metabolic benefits affecti the success of both the manufacturing and marketing of the final organic product.

Availability
Nutritive organic sweeteners that are commercially available in industrial quantities include agave, barley malt, cane, cane invert, cane brown sugar, corn, honey, juice concentrates, maple, molasses, oat, rice, tapioca and wheat. Important factors in the availability of these sweeteners include source of the raw material, supplier and pricing. Since large-scale production of organic products requires at least pallet loads of sweetener ingredient, only those organic sweeteners that are sold in minimum pallet load quantities of either 50-lb. bags, 55-gal. drums or bulk tankers are considered here. The source of the starting material is a critical consideration for certain target markets. For example, sweeteners from tapioca or rice are preferred for developing hypoallergenic or infant products due to their low allergen characteristics and ease of digestibility.

Domestically manufactured sweetener ingredients allow for stability in supply. Sweetener products manufactured in the U.S. do not risk import problems and are more adaptable to supplying customer needs. Importantly, technical assistance with regard to quality and versatility of the sweetener ingredient are more directly available and can be a significant advantage in product development. Additionally, it is possible to obtain liquid sweetener in bulk tanker loads rather than in drums or totes. Depend-ing on production size, the savings on packaging alone could be significant.

Consistent and reproducible sweetener ingredient quality is a function of the supplier. Product specifications giving ranges in sugar composition, taste, flavor, color, nutritional and microbial analysis should be provided by the supplier of choice. Choosing suppliers that have strong technical services, including product development assistance, can more readily assist in helping the customer select the right sweetener for the product.

Pricing is dependent upon the amount purchased or contracted. Stable and consistent purchase and supply agreements benefit both parties. All products are subject to fluctuations in raw material pricing. However, in the case of starch hydrolyzed sweeteners and cane products, the prices remain fairly stable because of worldwide commercialization of the crops in the organic and non-organic domain. Typically, for truckload quantities, starch hydrolyzed products range from about $0.85 per pound to about $1.50 per pound. Tapioca syrups are on the lower end and oat syrups are on the higher end of the pricing scale. Other sweeteners such as agave, fruit juice concentrates, honey or maple, are more subject to limitations in supply and tend to be on the order of pricing from $1.00 to as high as $2.00 per pound. Evaporated cane juice or related products such as brown sugar, invert cane juice or molasses are the least expensive of the organic sweeteners and tend to be in the $0.45 to $0.70 per pound range.

Composition
In addition to availability of flavoring agent, it is important to choose a sweetener based on the carbohydrate profile. The carbohydrate profile of a sweetener describes the distribution of simple and complex cabohydrates. Simple carbohdyrates or “sugars” as defined on the Nutritional Facts panel of food labels include predominantly one or a combination of glucose, fructose, maltose or sucrose. Complex carbohydrates, such as maltodextrin, are listed as “other carbohydrate” in the Nutritional Facts panel.

There are two broad category of sweeteners: those derived from the hydrolysis of starch, and those that are not. Starch hydrolyzed products are those sweeteners that are derived from the storage carbohydrates found in barley, corn, oat, rice, tapioca and wheat (Table 1). Starch is a carbohydrate molecule that is based upon chains of glucose. Hydrolysis of these chains using natural enzymes yields different quantities of glucose, maltose and complex carbohydrates. Typical carbohydrate profiles that result from starch hydrolysis are given in Table 2. The composition of sugars and complex carbohydrates in sweeteners resulting from starch hydrolysis can be controlled by the ingredient manufacturer to produce a variety of syrups with considerable differences in functionality and applications.

The other general category of sweeteners ingredients are those derived by concentrating (and sometimes hydrolyzing) the sap, fruit juice or nectar of plants. The storage carbohydrate in agave is inulin, which is a carbohydrate based on polymers (or chains of fructose). Hydrolysis of this product produces a sweetener composition of predominantly fructose with very little complex carbohdyrates. The composition of products such as honey, cane juice, fruit juice concentrates or maple syrup for the most part include only simple carbohydrates in the form of glucose, fructose or sucrose (Table 3). The sucrose in cane sugar can be hydrolyzed to fructose and glucose and is referred to as an invert cane juice.

The carbohydrate profile has an obvious affect on sweetness intensity. On a scale of 0 to 1, if granular sucrose is taken at 1, the sweetness intensity of the dry forms of other complex and simple carbohydrates are: maltodextrin (0.15), maltose (0.35), glucose (0.65) and fructose (1.25). The combination of these carbohydrates result in proportional differences in sweetness intensity. Sweetness intensity is directly related to the total carbohydrate content of the sweetener. A comparison of a syrup or solid form of a specific sweetener ingredient shows that the syrup, which contains a higher moisture content, has less total sugars and consequently, a lower sweetness intensity, than its solid counterpart.

The carbohydrate profile also affects the form of the product. The form of the product is critical for manufacturing. Many manufacturers cannot readily handle liquid products and vice versa with regard to solids. Consequently, if the final product is a liquid, a syrup form of the sweetener ingredient, which is usually less expensive, would be more economical and better suited for manufacturing. All forms of sweeteners are initially processed in the liquid state. If a dry form is not necessary, purchasing the liquid form can be considerably more economical. In general, sweetener ingredients containing fructose or larger concentrations of glucose and maltose are more difficult to dry and are not always available as a dry product.

Sweeteners also may contain molecules other than carbohydrates, including protein, fats and minerals. All of these affect the flavor of the sweetener ingredient to some degree. Some flavors are characteristic and desirable in food product formulations. However, in manufacturing products with desired target flavors such as vanilla or strawberry, the natural flavor of the sweetener may become overwhelming. In general, starch hydrolysis products made from the separated starch rather than the whole grain have a more neutral flavor associated with the sweetener. Other sweeteners, like evaporated cane or fruit juice, which are refined by crystallization, filtration or further separation of the non-carb-ohydrate components, result in more neutral-tasting sweeteners.

Besides differences in sweetness, the carbohydrate profile of the sweetener ingredient results in different functional properties of the sweetener ingredient. Humectancy, binding, mouthfeel, sweetness, osmolality, or freezing point depression are functions of different carbohydrates. For example, sweeteners containing just sucrose or only glucose tend to crystallize readily, and their use in confectionary products is well understood and utilized for this purpose. Fructose and maltose are very hygroscopic and add considerable humectancy to products. Maltodex-trins are much less hygroscopic, and in fact, are commonly used in combination with simple sugars to assist in the drying of glucose and fructose products. An example of this is powdered honey, which is a blend of maltodextrin and honey.

The carbohydrate profile also dictates the preferred usage or application of the sweetener ingredient. For example, high glucose syrups. which are predominantly glucose, are used in the beverage industry because the sweetness is maximized and provides a characteristic mouthfeel. Maltose syrups are preferred in the bakery industry because of their humectant property. Maltose syrups also are desirable in the confectionary industry for their combined sweetness and ability to produce hard candy that is not sticky. Sucrose-containing sweeteners have a high sweetness impact, and crystallization properties that make them most useful in confectionary and bakery products. Low-conversion starch hydrolysates, which have relatively small amounts of glucose and therefore low osmolality, are used as fillers and bodying agents in many baked goods and beverages. The higher sweetness of syrups containing fructose makes them particularly desirable for beverages. The humectant property of syrups containing either fructose, or combinations of glucose and maltose is advantageous in bakery and extruded bar products.

Metabolic Benefits
Metabolic benefits of a sweetener ingredient are an essential consideration for the marketing of the product. Organic products are being designed to meet specific target markets such as infant, elderly, sport or special medical needs. The source and composition of the sweetener ingredient dictates these ingredient choices. Hypoallergenic sources include rice and tapioca. Maple, honey, molasses and rice contain significant quantities of minerals and proteins that, while affecting flavor, also provide magnesium and phosphate, which are metabolically advantageous for the digestibility of the carbohydrate.

The types of sugars used also affect digestibility and utilization. Glucose, maltose and maltodextrins are easily digested, but over different periods of time. Glucose, for example, provides a source of quick energy and is digested more rapidly than maltose or maltodextrins. The more complex carbohydrates are preferred for nutritional or diet products providing long-term energy.

From a diabetic point of view, glucose results in a rapid requirement for insulin and may not be desirable. More slowly digested carbohydrates such as maltose or maltodextrins are preferred. Fructose, while providing advantages in sweetness intensity, is metabolized differently than glucose, maltose or maltodextrins. Fructose is metabolized directly to fat, which is an undesirable metabolic property of fructose. However, the metabolic pathway of fructose does not require insulin and is therefore preferred by diabetics. Additionally, more and more people are being reported as fructose intolerant, which means that they cannot metabolize fructose at all and causes some additional digestive problems and toxicity.

Hitting the Selection Sweet Spot
Choosing an organic sweetener is not a simple task. Once the type of product and the target market have been identified, the next step is to select a group of available sweeteners that will work in the selected product and market. Identifying the availability in terms of source and pricing, composition in terms of functionality, and required benefits will be the basis for this decision. Once the desired sweetener is chosen, research and development takes over to make the product. If the selection of the sweetener is a good one, the development, manufacturing and marketing of the product will be off to a good start.

Cheryl R. Mitchell, Ph.D., is President and Senior Research Chemist with Creative Research Management, Inc., a Stockton, CA-based developer of food ingredients and products, and manufacturer of nutraceuticals using low-acid, aseptic processing and packaging technology. Form-erly, Mitchell was co-founder of California Natural Products and head of its R&D operations from 1980 to 2000. A recognized world authority on starch and inulin, she is the author of 15 U.S. patents and patents pending for development of ingredients and products made from rice, soy, pectin and/or inulin. Mitchell can be reached at cheryl@crmcorp.net.