Natural Flavor Modification

Summary

• In addition to being a high intensity sweetener, stevia can also be used as a natural flavor
• The sweet taste of stevia based sweeteners already in formulation can be augmented with stevia natural flavors
• Words used to describe the flavor of stevia include sweet, bitter, licorice, astringent and metallicArtificial sweeteners may taste more “sugar-like” when stevia natural flavors are added to the formulation

Introduction

Stevia can provide more than just sweet taste. When stevia extracts or steviol glycosides are added to a product, the flavor profile can be modified or enhanced, such as bringing out flavors like cocoa, vanilla or lemon-lime. Since certain components of stevia have flavor modifying properties, some extracts can be considered natural flavors and labelled as such. Natural flavors include natural essences or extractives obtained from plants whose significant function in food is flavoring rather than nutritional (CFR, 2016). Stevia natural flavors can provide food and beverage companies with a plant-based option to enhance the flavor of their products while at the same time improving sweetness quality.

Benefits of Stevia as a Natural Flavor

The benefits of using stevia natural flavors are multiple. Steviol glycosides have a hydrophobic component (steviol) and hydrophilic components (mainly glucose) and can modify the flavor profile of foods and beverages. For instance, in a 30% reduced sugar version of a cola flavored carbonated soft drink, stevia natural flavor enhanced spice notes, balanced citrus/sugar flavors and provided a more syrupy mouthfeel (PureCircle, 2016). Inclusion of stevia natural flavors have been shown to positively benefit numerous product types such as lemon-lime soft drinks, apple juice, alcoholic cocktails, flavored beers, lemon flavored tea and flavored yogurt (PureCircle, 2016).

Other benefits revolve around stevia’s inherent sugar-like profile. By including stevia natural flavor, the sweetness profile can be improved to allow for up to a 20% reduction in added sweetener. Stevia flavors can also modify the profile of stevia based sweeteners already in the formulation. Lastly, if artificial sweeteners are included in the formulation, stevia natural flavor can round out those flavor profiles to make them more “sugar-like”. It does this by masking off notes such as metallic and bitter and optimizing the time related (temporal) aspects such as onset and duration of sweetness.

Case Study #1 – Lemon-Lime Flavor Enhancement

Lemon-lime flavored beverages have been popular for centuries. The use of lemon-lime flavorings in beverages dates to seventeenth century France and the first reference to carbonated lemonade was in 1833 (Emmins, 1991). Lemon-lime flavored beverages are still popular today and according to a recent report from Future Market Insights the market for citrus flavors is expected to reach 13,182 million US$ by 2025 (FMI, 2015). The sensory profile of lemon-lime flavors can range from delicate to bold and consumer preference for flavor nuances varies around the globe.

Lemon-lime flavors present particular challenges as terpenes, the largest class of compounds in lemon oils, are unstable in acidic environments (Clark, 1992). Common sensory attributes/flavor descriptors for lemon-lime flavors include: cooked, green, peely, fresh, seedy, pithy, juicy, aldehydic, green, over-ripe and terpeney (ASTM, 2017).

Natural stevia flavors can assist with the stability challenges and flavor nuances common to lemon-lime flavors. In a 50% reduced sugar lemon-lime carbonated soft drink made with a stevia sweetener, changes in flavor profile were found with the inclusion of a stevia natural flavor (PureCircle, 2016). The stevia natural flavor increased positive sensory attributes such as sweetness intensity, lemon flavor, lime flavor, and overall liking while decreasing negative sensory attributes such as bitterness, acidity, sweet aftertaste and bitter aftertaste (table 1).

Case Study #2 – Vanilla Yogurt Flavor Enhancement

Flavored yogurt is yogurt garnished, or added with, different flavors obtained from different sources like fruits and vegetables. Flavored yogurt encompasses several categories of yogurts based on criteria like low-fat/non-fat, frozen/regular and flavors from different fruits. The global flavored yogurt market is calculated to grow at a rate of 8.5% during the period 2017-2021 (Technavio, 2017).

Many flavored yogurts are high in sugar and health conscious consumers are demanding lower sugar alternatives (Gille, 2012). However, formulating flavored yogurt with lower sugar is challenging since sugar is essential for sweet taste but also contributes to the total solids of the product thus providing texture, body, viscosity and moisture retention (Popa, 2011). Consumers perceive yogurt with greater amounts of sugar as being sweeter, less sour and more aromatic (Chollet, 2013).

A consumer sensory study compared a vanilla flavored yogurt formulated with 50% less sugar using a stevia derived Reb A sweetener to a similar formulation made with an additional natural stevia flavor (PureCircle, 2016). Results found that the yogurt with added natural stevia flavor was higher in perceived vanilla flavor, higher in dairy flavor, lower in bitter, lower in sweet and bitter aftertastes, and higher in overall liking (table 2).

Conclusion

Stevia natural flavors provide cost-effective, sustainable solutions in line with consumer demand for plant-derived natural ingredients. They have the ability to enhance mouthfeel, improve sweetness quality and enhance flavor tonalities across a wide variety of applications.