Factoring for Functionality
Formulating Low- and No-lactose Frozen DessertsUnique challenges and opportunities exist in the formulation of low- and no-lactose frozen desserts containing both dairy and non-dairy derived ingredients, noted Phil Rakes, technical director, Main Street Ingredients. Determining whether the product should be absolutely free of any detectable lactose or if some low level can be tolerated will determine an efficient ingredient selection and formulation process. Additional information about the marketing demographics and desired labeling should aid in the decision about whether to proceed with a dairy-based formulation or a non-dairy one.
The dairy-based formulation decisions revolve around whether to reduce or remove the lactose by filtration, precipitation or hydrolysis. The decision(s) about this question dictate the type of protein- and fat-containing ingredients that need to be used in the formulation. The chart “Sample Starter Formulations” provides examples of how a no- or low-lactose dairy dessert can be achieved by very different ingredient choices. Some ingredients are more available than others, depending on volume requirements and access to the appropriate processing equipment.
The truly non-dairy based formulation options revolve around the use of plant proteins (i.e., often soy) and vegetable oil sources to build balanced and organoleptically acceptable emulsions that can be made and frozen in existing commercial processing equipment that often is located in traditional dairy plants. Since the ingredients are inherently devoid of lactose, the determination of an acceptable tolerance level for the targeted demographic groups largely is a moot point; however, the question of product-induced flatulence by the residual carbohydrates in some vegetable protein sources is not. It has to be aggressively addressed at the ingredient selection level and final formulation level in order to avoid products that look acceptable in the pilot plant and then die in the marketplace. By virtue of being “non-dairy,” these formulas require special attention to the choice of fats used because this often affects texture and maximum achievable overrun for the frozen dessert product, as well as saturated and trans fat levels.
“Formulating Low- and No-lactose Frozen Desserts,” Phil Rakes, Main Street Ingredients, phil.r@mainstreet ingredients.com, www.mainstreetingredients.com.
Polyol PotentialJoni Simms, manager-research technical services for Tate & Lyle, discussed sweeteners utilized in food systems; the synopsis of her presentation is outlined below.
Sweeteners provide much more than just sweetness to the finished product. In fact, they impart many other functional properties including: flavor enhancement, browning characteristics, serving as a bulking agent, lowering water activity and providing humectancy.
Sucrose is probably the most ubiquitous sweetener used in food systems, but other commonly used ingredients include corn syrups (liquid and solid forms), maltodextrins, dextrose, high-fructose corn syrup, fructose, sugar alcohols (polyols) and high-intensity sweeteners. When formulating with these alternate sweeteners, many different considerations must be taken into account, not the least of which is cost. The total solids content of the formula comes into consideration when replacing a dry sweetener with a liquid version, such as corn syrup, high-fructose corn syrup or liquid polyols. In addition to the sweetness factor, the molecular weight distribution of a liquid sweetener or sweetener replacement can have a large impact on the textural attributes of a food or beverage.
Other formulation considerations include the relative sweetness of each ingredient and its effect on overall sweetness in the formulation, as well as sweetness intensity and perception. Some sweeteners exhibit synergistic effects when used in combination, or have synergism with other ingredients in the formula, such as flavor components. The overall flavor of the finished product can be affected by the choice of sweetening system.
In dry mix systems, the particle size, bulk density and flow characteristics of sweetening ingredients are important to keep in mind, as well as their hygroscopic nature. Any ingredient that picks up water over time can severely affect the shelflife of a dry mix. A food formulator must consider all of the functionalities and properties mentioned above when choosing a sweetening system for food and beverage products.
“Functional Attributes of Liquid, Dry, and High-intensity Sweeteners and Sweetener Replacements,” Rheem Lock, Tate and Lyle PLC, Rheem.Lock@tateandlyle.com, www.tateandlyle.com.
Lessons in PectinThe criteria for selecting a suitable pectin type are soluble solids content, pH-value and consistency of the fruit spread. Pectin is one hydrocolloid with excellent shear and acid stability, noted Frank Mattes, president of Herbstreith & Fox Inc. Galacturonic acid, which is partially esterified with methanol, forms the backbone of this macromolecule. Commercial pectin is extracted from citrus peels that contain about 25% pectin, and dried apple pomace, which contains about 15% pectin. In jams, jellies and marmalades, pectin is used as a gelling agent. With its high acid stability, pectin supports flavor release.
High-methylester pectin is used for fruit spreads below pH3.5 with high soluble solids content (min. 55%), but for reduced- or no-sugar added fruit spreads, low-methylester pectin is the gelling agent of choice. Gel formation with low-methylester pectin is relatively independent of the product's pH-value and soluble solids content. Low-methylester pectin forms gels in conjunction with calcium ions; the amount of calcium present in the formula will influence the gelling behavior of the pectin by influencing the setting temperature and gel texture. Furthermore, this pectin can be obtained already standardized with calcium, or the mineral can be added separately.
It is possible to develop jellies with brittle texture or products with firm and gummy-like structure. Citrus pectin differs from apple pectin in its molecular structure, making it more sensitive to variances in the product's ionic strength. Citrus pectin has a brittle texture and a brilliant cut. With a smooth gelling behavior, apple pectin is the appropriate pectin to manufacture fruit sauces and toppings. Low-methylester pectin increases baking stability, decreases the tendency of syneresis in industrial fruit preparations and is easier to handle in production due to shear-thinning gel structures. The tissue of fruits and vegetables will be maintained by the formation of a shear-thinning gel structure.
In acidified milk drinks (for example, yogurt smoothies or soy drinks), proteins have to be stabilized because of their tendency to agglomerate under acidic conditions. Pectin will form a stable complex with protein so that protein precipitation is prevented. The amount of pectin needed depends highly on the pH-value, protein content and process technology. The optimal conditions to achieve stability are between pH3.8 and pH4.2 and homogenization of the batch.
Pectin will enhance the mouthfeel of low-fat dairy products and provide stability for many dessert products. Also, in low-fat spreads, pectin will form a distinctive texture with good spreadability and high mouthfeel.
“Pectin in Fruit Preparations and Beverages,” Frank Mattes, Herbstreith & Fox Inc., firstname.lastname@example.org, www.herbstreith-fox.de.
Optimizing Carrageenan in Processed Meat ProductsCarrageenan is a natural polymer extracted from various species of red seaweed. Its primary functions are texture modification, improving structural integrity and ensuring the physical stability of water. Seaweed families harvested for different types of carrageenan include Eucheuma, Chondrus and Gigartina. Kappa, iota and lambda are the primary forms of carrageenan used in the food industry. Lambda is a cold-soluble carrageenan that does not form a gel. Kappa and iota carrageenans, on the other hand, are heat-soluble and form gels upon cooling. Kappa carrageenans form strong, brittle gels, while iota carrageenans form gels that are less firm and more elastic. Different types of carrageenans can be blended to customize gel texture.
Type, concentration and composition represent the primary factors involved in carrageenan's functionality in meat applications. Although carrageenan's effect on texture is less apparent at extension levels below 50%, iota carrageenan has a tendency to make the meat product less firm and more elastic, while kappa carrageenans increase firmness. As with many hydrocolloids, carrageenans have optimum use levels where higher concentrations do not necessarily result in a better response. Adding more carrageenan beyond this point shows no further benefit and, in fact, may result in detrimental effects such as “stretch marks.”
The gel strength of kappa carrageenans can be influenced by potassium and calcium. The addition of either cation to kappa carrageenan will increase gel strength, with calcium having more of an influence than potassium. Sodium, on the other hand, reduces the gel strength of kappa carrageenans. Complete solubility of the carrageenan is not desired in most meat applications in which optimizing water retention is critical. The most important characteristic for carrageenan functionality is its swelling capacity. Salts such as potassium chloride and sodium chloride have an influence on the swelling of carrageenan, with potassium restricting the swelling of carrageenan more than sodium. This can create challenges when formulating low-sodium products.
Historically, carrageenan has been used at the processor level to increase cook yield and control purge during storage. The rising number of meals eaten away from home has created a new need: retaining the palatable qualities of foods during high temperature holding times and an increased number of reconstitutions. Carrageenan has shown good functionality in these applications.
“Optimizing Carrageenan in Processed Meat Products,” James W. Lamkey, PhD, FMC Biopolymer, email@example.com, www.fmc.com.