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of Success August 1998 -- Cover Story By: Lisa Kobs Contributing Editor Before becoming a food scientist, I couldn't understand why my homemade yellow cake and freshly squeezed lemonade didn't pack the full flavor of grocery-store products. It was only after touring my first flavor-manufacturing facility did I understand why my creations paled next to commercially prepared foods. Flavor chemists have access to thousands of flavor compounds capable of accentuating the subtle nuances of sweet goods. The literature tends to focus more on the application of flavor to savory, rather than sweet, food products. But with a basic understanding of how to properly use flavoring ingredients, the food scientist can create the right flavor system for sweet applications. Vanilla varietiesVanilla is the most commonly used flavor for enhancing sweet products. Vanilla beans are the fruit of the orchid Vanilla fragrans. Their characteristic flavor and odor are determined by the region in which the beans are grown, the length of growth time responsible for the development of flavor precursors, and post-harvesting processing. Regional processing methods significantly affect the quality and profile of the resulting bean flavor. The four most common processing methods - Bourbon, Mexican, Tahitian and Java Indonesian - vary in the length of time beans are grown before picking; duration of drying; and the drying method used, which can include sun-roasting and fire-curing. Vanillin is the most abundant of the 300 flavor components found in cured vanilla beans, but vanilla quality isn't based entirely on its vanillin content. Non-vanillin volatile and nonvolatile flavor components also make up this complex flavor. An aroma profile common to all vanillas is described as sharply acidic with slightly bitter back notes and a pronounced pungency. However, vanillas have characteristic flavors and aromas based on their country of origin. Bourbon-processed vanilla beans, grown mostly in Madagascar and the Comoro Islands, produce a high-vanillin-content vanilla described as rich, smooth, rummy and full-bodied. Mexican vanilla beans have a lower vanillin content and the vanilla lacks the body associated with the bourbon beans. Its flavor profile has been described as sharp, slightly pungent, woody, resinous, sweet and spicy. Tahitian vanilla is distinctively sweet, very fragrant and perfume-like, with coumarinic flavor and heliotropine notes. Java vanilla beans, from Indonesia, produce a vanilla described as deep, full-bodied, harsh, smoky and phenolic. Vanilla extract is extracted from the beans by using solvents such as alcohol, propylene glycol or glycerin. Singlefold extracts must contain 7.5 grams of moisture-free vanilla beans per 100 ml. A doublefold vanilla is an extraction prepared from double the quantity of beans. The maximum concentration prepared directly from beans is a fourfold. More highly folded products can be prepared by dissolving a calculated weight of oleoresin vanilla in alcohol or propylene glycol. Oleoresin vanilla is a dark brown semifluid extract obtained by solvent extraction of chopped beans under a vacuum. Vanilla also can be spray-dried onto a carrier for dry-mix applications, encapsulated or plated onto sugar. Vanilla WONFs contain some pure vanilla extract, supplemented with additional natural flavorings. Imitation vanilla flavorings can be made from numerous ingredients, such as essential oils, and natural and artificial flavors. They provide a range of flavor profiles for a variety of applications. These flavor blends can be formulated to be very high in strength for low usage and consistent quality. And, since natural vanilla extract can be expensive, these flavorings can translate into significant cost savings. The most common ingredient used in artificial vanilla is vanillin, a naturally occurring constituent of the vanilla pod. Because the percentage is so low, it is not economically feasible to extract it from its natural source. Synthetic vanillin can be made by the oxidation of eugenol, or clove oil. Today, it's typically made from the lignin obtained from cooking and chemical extraction of sulfite water (a waste product of the paper industry). This method requires vanillin to be labeled as artificial flavor. A new, two-stage procedure produces ferulic acid by fermentation, then converts it to vanillin in a secondary step. Vanilla-vanillin blends are made by adding USP vanillin to pure vanilla, and a variety of strengths and folds are available. Ethyl vanillin is a chemically processed flavor made from the coal-tar derivative, guaiacol. It has an intense, vanilla-like odor, and has a more powerful flavor than vanillin. It can feature a harsh "chemical" character when used at too high a level. A number of other, less well-known components delivering a vanilla flavor include: veratraldehyde, which is herbaceous and warm; heliotropine, which is sweet, spicy and floral; anisyl acetate, which is powdery and floral; and vanitrope, which has a warm, spicy medicinal sweetness.Sweet brownsThe category of sweet, brown flavors includes those flavors having the connotations of roasted, burnt or caramelized flavor systems, according to Carol Pollock, director, sweet and beverage flavor creations, Wild Flavors, Inc., Cincinnati. They can be extracted from botanicals and supplemented with other natural and artificial flavors, or they can be created by a reaction process. Flavors within this category include brown sugar, graham cracker, malt, honey, maple, molasses, caramel, butterscotch, coffee and chocolate. Flavor profiles for the base notes in many sweet brown flavors are similar. St. John's bread, an extract of the carob plant, forms the base note for many brown flavors. Brown sugar gets its distinctive flavor from a thin coating of molasses on the granulated sucrose. Butterscotch flavor is made from heating butter, sugar, fat and salt. Lipase activity from the butter, caramelization from heated sugars, and Maillard reactions from the sugar and protein generate this flavor. Many of caramel's flavor notes can be found in butterscotch, but with a twist. Botanical extracts that make up the sweet browns include black hawthorne, fenugreek, yerba mate and lovage. Brown flavors tend to contain more backnotes and mouthfeel rather than aromatics, and many of them have actual extracts of the ingredient in them, such as coffee or chocolate.MaltdownMalt's distinctive flavor can be found in breakfast cereals, baked goods, malted milk powders and beverages. Malt extract is made from germinated barley seed that produces enzymatic activity responsible for the flavor. Drying the grain provides shelf life and develops the flavor and color. To protect the enzymes, the heating must be carried out carefully, at low temperatures, while the malt is high in moisture. Once the moisture level has been reduced, the temperature is increased to bring about the flavor and color changes. By varying the amount and severity of drying, a range of malt colors and flavors can be produced. Malt products range from the lightly colored, mild-flavored versions with high enzyme activity, to dark-colored, highly flavored types with little enzyme activity. Enzyme activity can prove an important factor in the development of baked goods. Malt syrup is made by combining malt and corn meal, partially hydrolyzing the mixture, and extracting and evaporating the syrup.Sweet syrupsHoney. Honey is considered a sweetener, but one with a characteristic flavor. A complex flavor results from the sugars, acids, tannins, and volatile and nonvolatile components within it. The characterizing flavor is from the source of plant pollen. Honey in the United States typically comes from clover, but also is produced from alfalfa, raspberry, blueberry, orange blossom, buckwheat, sage, thyme and rosemary - all lending distinct flavors.Typically, darker-colored honey is stronger in flavor, and light-colored honey is generally very mild. Because of honey's mild flavor, large quantities are required to achieve high flavor strength. This might create problems in the finished product. Honey, being sweeter than sucrose, can lead to an overly sweet product, and its humectant qualities might cause problems with product texture. Using honey at high levels also can be quite expensive. The solution may be a honey flavor. The flavor chemist can engineer an excellent artificial honey flavor, and a blend of honey and other sweeteners boosted with a honey flavor would provide the desired flavor characteristics at a lower cost without the accompanying texture problems. Often a mixture of real honey and honey flavor can taste more like honey than actual honey does. Maple syrup. Maple syrup, the sap of black maple and sugar maple trees, is another sweetener containing a characterizing sweet brown flavor. The sap is concentrated through an evaporative process, which thickens it and intensifies the flavor. Syrup right out of the tree is mostly sucrose. Evaporation produces some glucose and fructose upon inversion at a low pH. One group of flavoring components comes from the ligneous materials from the sap, but a second group is formed by the caramelization of sugars. Imitation maple syrup can be constructed from corn syrup with added maple flavor, but Pollock says these products tend to be less sweet and very flat. Salt often can bring out their flavor. Maple syrup is also a humectant, so many of the associated problems can apply. Maple flavors have been developed by the extraction of botanicals, such as fenugreek and lovage, or chemical compounds, such as cyclotene and methyl cyclopentenone. It's important to distinguish real maple flavor from maple syrup flavor. Processed, artificially flavored maple syrups have become almost a standard of maple flavor, while a true maple flavor has a completely different character. Molasses. Molasses, the concentrated extract of sugar cane, is a strongly flavored, slightly sweet syrup. Whole sugar-cane juice is evaporated into a high-density syrup containing a major portion of the solids, then put through a crystallization step that removes sucrose crystals from the liquid phase. The remaining liquid undergoes additional recrystallization steps that concentrate the molasses content. By the third recrystallization step, the molasses has developed its characteristic strong blackstrap flavor. Molasses flavor has found a niche for itself in some specialty baked goods and those foods flavored with sweet spices, such as cinnamon and ginger. Lower, uncharacterizing levels make an excellent tool for building base notes in many sweet brown flavors. As with all natural ingredients, molasses color, flavor and composition will greatly depend on the region and climatic conditions in which the sugar was grown. Blending helps ensure consistent and uniform color, flavor and ash content. Reaction flavorsChocolate. Chocolate and cocoa start with cocoa beans, which grow in elongated pods. The pods are broken, and the beans and pulp are fermented microbially and enzymatically. This process promotes development of chemical precursors, later becoming important flavor components. The beans are dried and roasted. This converts the flavor precursors to a complex mixture of many aromatic compounds, including esters, lactones, pyrazines, hydrocarbons, alcohols, aldehydes, ketones, phenols, sulfides and more. The resulting product, a nib, is ground to release fat from the cells, which melts from heat generated by grinding. This liquid product, chocolate liquor, forms the base for all chocolate products. Defatted chocolate liquor becomes cocoa, and the removed fat is called cocoa butter. Chocolate itself is a combination of different amounts of chocolate liquor, cocoa butter, sugar and other ingredients. Milk powder, whey, and natural and artificial flavors also are added to alter the flavor profile. Much variation occurs in chocolate's flavor profile, ranging anywhere from a deep, dark baker's chocolate to a sweet, milky version. An alkali treatment (Dutching) will neutralize some of the acids, producing a more bitter and astringent product in the pH range of 6.0 to 8.5. With its darker (or even reddish) color and full, rich flavor, Dutch cocoa is well-suited to baked goods and cake mixes and coatings. This higher pH can be responsible for color changes to the food matrix, as with the reddish tones of devil's-food cake. Nonalkalized cocoa (referred to as natural processed cocoa) has a more fruity and acidic cocoa flavor, falling in the neutral-to-slightly-acidic pH range of 5.1 to 5.9. The mild fruity notes come through especially well in high-moisture or fat-based systems. Chocolate flavors typically contain actual chocolate, or extracts and distillates from the cocoa beans. Artificial chocolate is difficult to make without any real chocolate extractive components because of the complexity of the flavor, according to Gary Reineccius, professor in food science, department of food science and nutrition, University of Minnesota, Minneapolis. "It's very difficult to make a totally natural chocolate flavor, because the chemicals comprising chocolate flavor aren't available in natural form, and the flavorist won't even get close to a mediocre natural chocolate flavor by putting together pure chemicals without adding chocolate products." Vanilla and vanillin are commonly added to enhance the flavor of chocolate. They also are the primary source of flavor in white chocolate, which is a blend of cocoa butter, sugar and milk. Another developer's trick to increase the perception of chocolate flavor is to darken the food matrix. The deep brown color of a chocolate cake will send connotations of rich chocolate flavor to the consumer's mind before it is ever tasted. Coffee. Coffee flavor is derived from the berries picked from the evergreen trees Coffea arabica L. and Coffea robusta L. These fleshy berries are dried, hulled and fermented into green coffee beans. Roasting reduces their acidity and develops the aromatic oils that give coffee its characteristic flavor and odor. Coffee flavor depends on bean variety, country of origin, and climatic and soil conditions. Arabica coffee accounts for most of the world's coffee production, and is superior in flavor to the robusta variety. With its rougher, more earthy flavor, robusta coffee lacks the delicacy and subtlety of the arabica beans. Coffee often is categorized by country of origin, with these names signifying the variety's flavor and character. Some of the most common coffee types are: Brazilian, Colombian, Costa Rican, Guatemalan, Indonesian Java, Indonesian Sumatra, Jamaican Blue Mountain, Kenyan, Kona Kai from Hawaii, Mexican Maragogipe, Indian Mysore, and Tanzanian Kilimanjaro. Degree of roasting determines a coffee's delicacy and richness. A light roast is used for beans with subtle flavors that could be ruined or lost by using a stronger roast. A medium roast has more flavor and aroma than a light roast, and the dark roast gives the beans a very strong flavor and aroma. The flavor of coffee has many elements, which is not surprising as it contains more than 300 compounds. Aside from the adjective "coffee-flavored," it can be called acidic, full-bodied, mellow, mocha, soft, nutty, rich, smooth, acidic, spicy, smoky, winey, heavy, chocolate, bright and earthy. Coffee flavors have been developed by profiling the extractives of the native beans for their flavor, and then analyzing these chemicals and their composition. Reineccius explains that a compound called furfurylmercaptan can help the developer create coffee flavor without using coffee. Since this flavor isn't available naturally, it must be labeled as artificial. It's impossible to make a natural coffee flavor without starting with some coffee, as there are no other naturally occurring substances that capture this flavor. "Making coffee flavors challenges the flavor chemist because different levels of oils exist in the beans themselves," Pollock explains. "In addition, different amounts of oils can be extracted, and coffee contains many reactive ingredients. Coffee flavor is temperature-dependent; freshly brewed coffee loses its impact within a minute of brewing." Caramel. Applying heat to sucrose above its melting point catalyzes the reaction of caramelization. Sugar breakdown products create a mixture of aldehydes and ketones and, most importantly, furanones. These can be characterized as caramel-like, sweet, fruity, butterscotch, nutty or burnt, and are the backbone of the caramel flavor. "The decomposition of sucrose by heat is a challenge in a plant situation because it is difficult to control the reaction," Pollock says. "It's much easier to simulate caramel flavors by using compounded flavors." Maltol, ethyl maltol and cyclotene are components commonly found in caramel flavors. Caramel candy's flavor comes from heating and concentrating sugar and milk, so simulated caramel flavorings often are enhanced by added dairy notes. Caramelization occurs in baking and cereal manufacturing, and the product base can be enhanced by adding caramel-type flavors. Fruit flavors. Fruit flavor can be added either in the form of whole fruit, fruit juice, juice concentrates, purees, pastes, dehydrates, spray-dried powders and flavors. Whole fruit, which contains seeds, will have the green and bitter components. Whole fruit also will contribute cell-wall material, which might prove detrimental to the finished product. Unprocessed fruit still will contain active enzymes that can cause off-flavors and off-colors over time if they aren't inactivated. Juice is obtained by the mechanical pressing of ripe fruit, and its flavor greatly depends on the quality and degree of ripeness found in the original fruit. Expressed juice won't taste like the actual whole fruit because the characteristic volatile components - the source of the aroma - are found in very low levels. Fresh-fruit flavor can be achieved by blending juice with aromatics recovered from the rest of the fruit. Natural and synthetic flavors can be added to juice to boost flavor and reduce expense. All fruit juices contain extraneous matter, such as proteins, pectins and gums, that contribute cloudiness and viscosity changes. These might not be removed, based on the finished product. Pasteurization reduces potential spoilage, but involves high heat, which can result in heat-catalyzed chemical reactions of the flavor compounds. The preservative sodium benzoate can contribute a bitter flavor even when used within the legal limits. Dehydrated fruit juice contributes real fruit, but its flavor is often lost or its character changed due to the heat treatment. Because of its hygroscopic nature, it can lump and become difficult to work with. Freeze-dried juice has a much higher flavor quality, but is typically more expensive. Fruit juices often contain too much water in relation to their flavor strength, so they're concentrated. Concentration via vacuum distillation separates solid matter from the aromatic substances. These can be partially recovered and added to the concentrate, but the finished product still will be deficient in top notes. Freeze concentration uses no heat, so the finished product's profile is closer to real fresh fruit. Citrus fruits are made into essential oils because much of the characteristic odor is found in the peel's oil. Citrus oils have a high percentage of terpenoid hydrocarbons. These carry smaller levels of oxygenated compounds such as alcohol, aldehydes, ketones and esters. These are responsible for the characteristic odor and flavor. The terpenes contribute an odor/flavor of their own, and a citrus oil with the terpenes removed will be flatter-tasting and lack freshness. Terpenes are typically removed because they will oxidize, resulting in lower flavor quality. To develop a fruit flavor, flavor chemists start with what nature starts with: amyl, butyl and ethyl esters, organic acids, aldehydes, alcohols, ketones and lactones. These build, characterize and enhance fruit flavor. Some chemicals instantly conjure the image of the fruit they are meant to depict, such as amyl butyrate with its banana-like scent. Others, such as ethyl acetate, will suggest an overall unidentifiable fruit note that will enhance and round out the flavor. Green, fresh, earthy, overripe, cooked and floral notes all can be added for complexity. Organic acids occur naturally in fruits, giving them their distinguishing flavor and bite. The same flavor will deliver differently depending on the acid used to enhance it. While citric and malic are very close to each other chemically, their profile and sharpness in the mouth vary considerably, and each individual acid will enhance fruit differently. Citric acid enhances cherry and strawberry flavors, Pollock explains, and malic works with apple and pear. Blends of malic with tartaric are great for raspberry as the tartaric has a slight metallic aftertaste that fits with the seediness of a berry. The goal is stimulating other areas on the tongue. A subliminal amount of acidity, not specifically tart, can work well to add a different dimension. Phosphoric acid at less than 100 ppm, or acetic acid used at a level at which the scent isn't noticed, are other atypical ways of using acidity. Grape typically has been associated with the use of malic and tartaric acids, according to Jim Lewis, director, flavor applications, Bush Boake Allen, Montvale, NJ. Today, citric acid is often used to enhance grape flavor, and many people have become accustomed to the different flavor that results. Because of this, some will perceive an off-note to grape enhanced by tartaric or malic acids. Nuts. Nuts can provide foods with a variety of flavors that take on a whole new dimension when roasted. Whole nuts will contribute flavor once bitten, and release their flavor volatiles. But unless they are in a ground or paste form, the nut flavor won't permeate throughout the food matrix. Nut oils, containing the flavor volatiles of the nut itself, can be expressed and used as a delicate flavoring agent. Nut oils are typically mild in flavor, and must be used in large quantities to contribute any significant flavor properties in most processed foods. Their many unsaturated fatty acids are subject to rancidity and off-flavors. Another option is using a nut flavor. "True and characteristic nut flavors can be developed from synthetic ingredients that not only convey a nutty characteristic," Pollock explains, "but can simulate the specific nut, such as a filbert, hazelnut, cashew or pecan." Many nuts contain allergens, so a great need exists for flavors that aren't nut-based. Using only natural flavors restricts the flavor chemist's compound options. A nutty character can be developed, but it won't possess the unique nuances of the individual variety that can be found in the artificial flavors. Since these natural flavors require the use of actual nut extractives, it's not easy to develop an all-natural flavor that is allergen-free. Because nuts typically feature high fat levels, the flavor and mouthfeel of fat is typically associated with the true nut flavor. A fat-free praline muffin will have a better pecan flavor if a small amount of fat is added to the formulation, and low-fat peanut butter will have a more believable flavor delivery and mouthfeel if a small amount of oil is added. Spices. What would pumpkin pie be without the spiciness of cinnamon, ginger and cloves? Spices are defined as natural vegetable products used for flavoring, seasoning and imparting aroma to foods. Small quantities of spices add dimension to a food product, and their connotations of naturalness appeal to the consumer. However, spices vary in strength and flavor profile; their flavor is often less evenly distributed within the food matrix; they can represent a microbiological hazard; and they lose flavor strength upon storage. Occasionally, a large spice volume can make the food matrix muddied or speckled and bitter-tasting. Often, an essential oil or extracted oleoresin is preferred. Essential oils help control flavor strength and character. They are microbe- and enzyme-free, and are stable under good storage. One drawback of the essential oil is that it only represents a portion of the total available flavor in a spice. The volatile oil of ginger won't provide any of the pungent qualities because these qualities come from non-volatile components. Oleoresins contain the volatile and nonvolatile compounds from the spices, so their flavor is more characteristic of the spice. Oleoresins are thick, viscous liquids, making them difficult to incorporate into the food matrix evenly. They also are very concentrated, so weighing errors are dramatic. Spices also may be found in the form of essences, emulsions and encapsulates, and plated onto sugar. Often, a blend of forms represents the perfect solution. In a cinnamon roll application, cinnamon essential oil will provide the flavor strength, while a dusting of ground cinnamon will give a quality, homemade appearance. Dairy Flavors. Many sweet products - including pudding and ice cream - are made with a substantial percentage of dairy products. Milk and cream have low flavor levels. Yet, the flavors they do possess come from proteins, lactose, salts, free fatty acids, dimethyl sulfide, and the carbonyls acetaldehyde, acetone and formaldehyde. Butter gets its flavor through the fermentation of cream by bacterial cultures. This produces flavor components such as diacetyl, acetoin and acetaldehyde. To accurately flavor a system that might contain substantially less dairy products (or none at all), the notes of milk, cream and cream cheese might need to be added as the characterizing flavor or for background notes. Dairy and butter flavors can be artificially simulated from butter-flavored compounds such as diacetyl and butyric acid, made naturally through enzymatic activity such as the lipolization of butter oil, natural starter distillates or products of fermentation. Even when dairy products are used, the flavor still can be improved or the cost reduced by adding dairy flavors. Cream and butter flavors are mild, so it's often the mouthfeel and richness that is perceived as dairy flavor. This means an integral part of dairy flavor, like so many other flavor systems, is fat. For a flavor to be perceived as a dairy fat flavor, there must be some compensation to the mouthfeel with either the addition of vegetable oil or some type of fat mimetic system.EnhancementMaltol and ethyl maltol can improve overall flavor, potentiate sweetness, increase the sensation of creaminess, mask bitterness and suppress an acid bite or burn. Marketed under the name VeltolÆ by Cultor Food Science, Ardsley, NY, these ingredients have a mild flavor and sweet caramel-like odor. While both compounds must be labeled as artificial flavors, the product line also includes product enhancers that can be labeled as natural flavor. The high-intensity sweetener thaumatin is a protein extracted from the Katemfe fruit, which grows in Western Africa. Thaumatin has been shown to interact with most taste receptors, promoting a heightened response to sweeteners and certain flavor compounds. It allows the flavor to be effective over a longer period of time and extends its profile to provide a fuller taste and more body. The ingredient enhances flavors, particularly those with strong notes such as peppermint, ginger, cinnamon and coffee. It has synergistic effects with nutritive as well as high-intensity sweeteners. Flavor-masking of metallic ions - including sodium, potassium and iron - is an additional application. Thaumatin is approved for general use in the United States and has been approved as Flavor Extract Manufacturers Association (FEMA) GRAS. Since it is obtained by a natural process, thaumatin can be labeled as an all-natural ingredient. Licorice extracts, derived from the roots of the licorice plant Glycyrrhiza glabra, also possess flavor-potentiating properties. Marketed under the name MagnasweetÆ by MAFCO Products, Camden, NJ, Magnasweet or licorice extract is the ammonium salt of glycyrrhizic acid. Two forms are available: ammonium glycyrrhizinate (AG) and mono-ammonium glycyrrhizinate (MAG). MAG is a white crystalline powder stable in low pH systems, and retains less of the licorice flavor - this makes it applicable for a range of products. A brown powder, AG has more of the characteristic licorice flavor which can impart an appealing, difficult-to-detect flavor nuance when used at low levels. At higher levels, it can strengthen and improve flavors such as chocolate or maple. AG and MAG are 50 times sweeter than sucrose, and due to Magnasweet's synergistic action with sweeteners, it becomes 100 times sweeter than sucrose when combined with cane sugar. It also will react synergistically with other nutritive and non-nutritive sweeteners. Other attributes include the ability to: enhance and magnify natural and artificial flavors; mask bitter and astringent aftertastes; and soften harsh notes. It also can be used for flavor modification at very low levels. Magnasweet is approved as FEMA GRAS.Out of the ordinaryGoing beyond the obvious can lead the developer into flavor areas that might sound unlikely, but the results speak for themselves. There's no reason why a grape flavor can't be enhanced by a less recognizable flavor such as melon or plum, which provides roundness and depth. Fantasy flavors, or flavors with no real characterizing base flavor, can come from all sorts of unlikely blends and can be great fun to the creative flavorist. "What the developer is doing is adding interesting notes," says Reineccius, "and even though the product is sweet, the flavors don't necessarily have to be. Odd items can contribute interesting notes - there's really no limit. Garlic oil works nice in butterscotch because it provides a warm feeling, and chocolate often has been enhanced with low levels of fermented soy-based flavors." Using 300 ppm of monosodium glutamate in maple syrup will help open up taste buds, and make the flavor come alive through this very viscous product, Pollock says.Screen testMany food companies develop a small list of preferred flavor suppliers that their development team must choose from. While this makes ingredient procurement easier, it is often at the expense of the flavor profile. It's difficult to find a flavor company that can be all things to everyone. Tasting five different orange flavors from five different companies will demonstrate how different the interpretation of orange flavor can be. Using only one flavor company limits the developer to the chemicals that the firm uses as building blocks. Often, a flavorist will develop a signature style that, although very appealing, can lead to tiresome and repetitive flavor systems. Some companies specialize in vanilla flavors, while others do a better job with fruit flavors. One company might have a patented technique for spray-drying flavors that could solve stability and shelf-life problems. Often, a blend of two different company's grape flavors will work synergistically with each other, so mixing and matching can be a great way to obtain a unique creation. Another mistake is to only work with the larger, established players. Flavor quality from some of the smaller and newer companies often is as good as, or better than, some of the industry giants. When 20 new flavors come in, it's tempting to open the bottle, take a sniff, and make a decision. But flavors shouldn't be screened in their pure state, as many of the notes will appear unbalanced or even unpalatable. The best screening method is trying a flavor in its final application. With a cake, bake a plain batter containing the flavors and evaluate to determine how they interact with other ingredients and heat. With time lines as short as they often are, and 30 flavors staring at you from the shelf, this may be unfeasible. The next best thing is to dilute the flavors in water, comparing them for quality, character and impact. Just as a sprinkle of sugar will tone down the bitterness of a slice of cinnamon toast, sweeteners make flavors come alive. This phenomenon is apparent when screening flavors. Diluting an almond extract in plain water will produce a slightly bitter and unpleasant liquid that would appear to contribute very little to the finished product. Adding sugar will accentuate its rich and fruity notes and bring out flavor more realistically. Many of the components of sweet flavors don't have a very pleasant flavor on their own, so it's important to screen sweet flavors with sweetened water. It also takes a great deal of imagination to recognize the capacity within a flavor.Surprise, surpriseAlthough flavors are typically used at low usage levels, in some specific instances, even a small amount is often enough to have a negative impact. Color changes are one key issue. A natural raspberry flavor, made with real juice extract, might contribute enough natural pigment to turn a granola bar pink, depending on the usage level. Natural vanilla extract is a caramel brown color, and might make a custard appear muddy. Vanillin can react with iron to form a pinkish-colored compound that might prove unappealing in lighter products. Chemical reactions can occur, resulting in undesirable flavor changes, Reineccius says. Aspartame reacts with aldehydes found in cherry, vanilla and cinnamon, and will lose sweetness, which transfers to flavor delivery. Piña colada flavors often taste soapy. The pineapple flavor contributes lipases, and the coconut flavor adds C-12 fatty acids. Once the lipase activity breaks apart the fatty acids, the result is this objectionable flavor note. The best way to prevent surprises, or quickly fix them when they occur, is effective and continuing communication with the flavorist.Sweet effectsSweet flavors are obviously used most often in sweetened products, and the sweetening system is typically a large percentage of a formulation. Sweeteners affect the flavor by enhancing the profile; providing differing degrees of sweetness; offering their own contributing flavor; and by changing flavor character and delivery in the mouth. This was a problem for the beverage industry when it went from sucrose-sweetened products to dietetic beverages and drinks sweetened with high fructose corn syrup, Reineccius recalls. The same flavor systems no longer delivered as they had previously, resulting in different-tasting beverages that required flavor reformation. The way sweeteners interact with flavors and deliver to the human olfactory system is quite complex and almost totally unpredictable. When flavoring based on sweetness concentration, mildly sweetened products require the use of less flavor as the flavor comes through more clearly. At very high levels, sweetness becomes intense and begins masking the overall flavor. As a result, higher flavor levels are required. Obviously, molasses, honey, malt syrup and brown sugar all contribute a desirable or undesirable characteristic flavor, in addition to sweetness. But some not-so-obvious sweeteners also contribute their own flavor. Sucrose possesses a flavor that can be overpowering when used at high levels in delicately flavored systems, and glucose can begin contributing a burning or bitter taste in higher concentrations. Some of the polyols impart bitterness and a cooling sensation to varying degrees. Aspartame has a relatively clean flavor, but tends to flatten flavor slightly. Saccharine and sucralose can contribute bitterness or metallic notes, and acesulfame K can have bitter notes at higher concentrations. Fructose, lactose and glucose are all reducing sugars that take part in the Maillard reaction. This can be desirable in a baked good, or undesirable in a vanilla-flavored HTST-processed beverage that winds up turning a butterscotch color. Not all sweeteners will participate in this reaction at the same level. Higher-DE corn syrups, for instance, react more readily than sucrose, so the choice of sweeteners has a significant impact on the degree of Maillard flavor development.Choosing formsWhen choosing a flavor, its physical form can be very important to the end result. Liquid flavors can come in water-soluble, water-dispersible or oil-soluble forms. Dry flavors can be spray-dried onto a variety of carriers or encapsulated. In a dry mix, the developer is obviously limited to dry flavors, but the choice isn't so obvious with two-phase products. An ice cream typically will use a liquid flavor. However, ice cream contains fat and water, so deciding whether to use a water-soluble or oil-soluble flavor isn't so cut and dried. "A two-system approach, where some of the flavor is partitioned into the fat phase and some into the aqueous phase, can be good idea when a simple system doesn't work," Lewis says. With a baked good, the choices increase further still as either a dry or liquid flavor can be used, and again either in a fat- or water-soluble form. A water-soluble flavor with an alcohol solvent might lead to evaporative losses in baking. Here, a solvent base of propylene glycol or glycerin, or an oil-soluble flavor, would eliminate flash-off and reduce flavor loss. In a beverage application, the choice is usually an emulsion to promote stability. However, emulsions create a cloudy appearance, so a water-soluble flavor would be used for a clear application. Most of the problems associated with flavors and processing are linked to evaporative losses due to processing with open systems. As a rule, the faster and hotter the process, the less severe the flavor damage. It's best to use a closed system in which the flavor has nowhere to escape. But even in a closed system, the high heat still will cause some flavor change. When a closed system isn't an option, it's best to use a flavor that's been developed to withstand high heat. The flavors in candies, fried snacks and hot-pack foods must be designed to remain stable at higher temperatures. These flavors often are based on propylene glycol and glycerin to prevent flash-off, and they also can contain highly folded flavors. Many sweet flavors are quite stable as they are based on plant extracts and already have been processed, according to Pollock. The best method for developing products with balanced flavor is learning to speak the language of the flavorist, and to have them involved at the conceptual get-go. Don't be afraid to answer their questions truthfully. The flavorist isn't trying to steal your concept. Instead, he needs this information to provide the best product possible for a given application. How many hours, dollars and pounds of ingredients have been lost because a flavor didn't act as predicted? Granted, there's no guarantee changes won't occur, but at least you'll rest easier knowing you did everything possible to prevent it.Learning the LingoIt's important for every food scientist to learn the language of flavor, because within every flavor category, a subset of many characterizing flavor descriptors exists. A fruity strawberry can be very unripe and green, very ripe, seedy tasting, or cooked so as to resemble preserves. It's not enough to say one is seeking a chocolate flavor, because the terms tobacco, barny, fruity, musty, milky, woody, oily, green, hay-like and floral all have been used to characterize chocolate flavor. Telling the flavorist one is looking for a vanilla that is creamy, custardy, spicy, smoky, floral, caramellic, baby-powdery or fatty will save time by reducing the number of samples that need to be submitted and screened, resulting in shortened development time. Discussion can be promoted and expectations clarified by using food-item terminology, such as fruit punch, cough syrup, vanilla wafers or even brand names like Captain CrunchÆ cereal and Juicy FruitÆ gum. Developers and flavorists must have this list of vocabulary words, and agree on what flavor is being perceived. If one person describes a flavor as "hay-like" and the other person describes the same flavor as "barny," then there should be a common word agreed upon so everyone knows this particular flavor will be described as such. This is not as easy at it might appear, as each individual has his own sensory strengths and abilities to communicate their reactions. Carol Pollock, director, sweet and beverage flavor creations, Wild Flavors, Inc., Cincinnati, recalls a recent exercise in which a group was tasting blind and there were differences of opinion as to which type of apple a flavor represented. After purchasing eight varieties of apples, and eating them in conjunction with tasting the flavors, it was much easier to match the character to the apple. Having a model is one of the basics for developing a flavor profile.Lisa Kobs, M.S., is a research food scientist with the food consulting firm of Food Perspectives, Plymouth, MN. Back to top |
SupplySide
The Sweet Taste of Success
Posted in
Articles,
Beans,
Beverages,
Chocolate,
Flavor,
Fruit,
Natural,
Sensory,
Science & Research,
Fruits / Vegetables,
Malt Extract
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