When formulators pay careful attention to development details, the payoffs are huge. Former PowerBar formulator Jones Chan tells what it takes to make consumers love your product
The energy bar market segment is extremely crowded, with many choices for consumers. For an energy bar to be successful in the marketplace, it must possess a 'wow factor' in both taste and performance. It must have great appearance, flavour, aroma and texture. The formulation must be science-based with valid performance claims. When consumers use the product, they must have a positive experience, or they will make another buying choice.
It is no longer acceptable to adopt the 'launch and fix' strategy, because the playing field is too competitive. Marketers have only one chance to win consumers. The product must be optimal by the time it gets to market. It is therefore critical that the formulation be well tested, meeting organoleptic and performance hurdles prior to launch.
Formulating great-tasting, functional energy bars is not an easy task. The system is complex, with many potential physical and chemical interactions that can adversely affect the appearance, taste, texture and stability of the bar. In many instances, these reactions won't surface immediately. This adds another level of complexity and challenge for formulators.
Formulators must add specific nutrients and bioactives to achieve efficacy, and the amounts required of each may adversely impact taste and shelf life. In order to minimise the negatives, formulators should focus on the following key areas of development.
Binders/sweeteners: Typically, brown rice syrup and high fructose corn syrup, also called invert sugars, are used as the primary binders and sweeteners in performance bars. Brix (a hydrometer scale for measuring by weight the amount of sugar in a solution) can be adjusted to optimise the sweetness and texture of the bar. The syrup is typically added at 80 to 84 Brix to the dries (dry ingredients). Lower Brix syrup is easier to handle from a processing standpoint but may make the core too loose to extrude. Sweetness and energy density are directly proportional to the Brix of the syrup. These are important considerations when determining the appropriate Brix to use.
Formulators should avoid evaporated cane juice as part of the binder system because it contains 50 per cent sucrose, which tends to crystallize and harden the bar over time. Sugar alcohols such as maltitol and glycerin, however, are excellent humectants; they are used to keep bars soft and pliable over time. For most applications, especially in high-protein bars, using these ingredients at five to eight per cent is most effective. Adding too much of them, however, has a laxative effect.
Protein: Another major ingredient that can significantly affect the taste and texture of an energy bar is protein. There are several types of protein to select from, including whey, casein and soy. They come in concentrate or isolate form. Use of isolates is preferred over concentrates. Isolates and concentrates contain approximately 90 per cent and 70 per cent protein, respectively. As such, using isolates is an effective way to deliver protein while keeping bar size down. In the case of soy, the isolate has significantly less beany notes than concentrate, a real plus when formulating a great-tasting soy-based bar. When formulating with milk proteins, the isolate form contains less lactose than the concentrate, an important consideration for lactose-intolerant consumers.
Texture: The protein level and type can also significantly affect texture over time, making the bar hard and dry. Even the same protein isolate from different vendors can affect texture differently. Also, how the protein is processed can have a huge bearing on its performance. It is therefore critical to evaluate each protein individually in the core matrix and conduct short-term shelf-life testing to flush out potentially problematic proteins. This is especially important when one is formulating with multiple protein types. Typically, a two-week accelerated study will provide a lot of directional information and is worth the extra time and effort.
Some high-protein bars contain hydrolyzed protein, which is usually gelatin. It has been successfully used to increase the protein level without making the bar hard and dry. The negative, however, is that hydrolyzed protein can cause a bitter aftertaste. Here's a rule of thumb: the more hydrolyzed the protein, the more bitter the taste. This is why adding individual amino acids, such as branched-chain amino acids, at any efficacious level may pose flavour challenges. In the case of gelatin, not only is taste negatively affected, but it also is an extremely poor-quality protein compared with whey or caseinate.
The Nutrition, Labeling & Education Act (NLEA) has guidelines that expose this fact to the consumer, but often the marketer is not in compliance. The NLEA requires that companies state the daily value of the protein when making a protein nutritional content claim, such as declaring the amount or quality of the protein. The "daily value" takes into consideration the protein digestibility corrected amino acid score, which is an indicator of protein quality. A lot of high-protein bars containing hydrolyzed protein (gelatin) often do not declare the 'daily value.' This is because hydrolyzed protein can significantly lower the daily value and give the product a labeling disadvantage.
In many energy bars, formulators add puffed rice nuggets and/or soy nuts for flavour, texture and nutrient delivery. The nuggets can be fortified with protein, an extremely effective way to increase the level of protein in the bar while minimising the negative texture impact. Too much pressure to the core during the blending and extrusion process will cause the puffed rice to fracture. When this happens, the bar becomes dry and stiff over time. To avoid this problem, here are some suggestions:
- Add the puffed rice or soy nuts as the last ingredient to avoid over-mixing.
- Make the core less stiff by reducing the shear force during blending and extrusion. This can be achieved by either increasing the syrup temperature or decreasing the Brix of the syrup.
- Use protein-fortified puffed rice or soy nuts that are less prone to fracture.
In many granola-type energy bars, puffed rice or soy nuts are mixed with dried fruits. This combination may cause a texture problem if the moisture content of the fruits is too high. The moisture of the fruits or fruit purée can migrate to the puffed rice or soy nuts, making them soggy over time. To minimize the moisture gradient shift, formulators should try to have the moisture contents of the dries be as close to each other as possible and set the final water activity at or below 0.60 for shelf life and microbiological stability.
Flavour: Clearly, several options exist for minimising the negative effect of certain macronutrients on the taste and texture of energy bars. Micronutrients, such as vitamins and minerals, also can change the organoleptic attributes and shelf-life stability of bars. All energy bars these days seem to contain vitamins and minerals. This trend appears to be affecting the increase in the number and per cent of the recommended daily allowance of micronutrients in energy bars.
With this comes certain development challenges for the formulator. The B vitamins are bitter and may cause flavour problems over time. Calcium may cause mouthfeel issues. Minerals such as iron, copper and zinc may interact in the system and cause flavour, colour and chemical instability. Some of these nutrients may require encapsulation.
Beyond these hurdles, there may be mixology problems. Steps must be taken to ensure that the micronutrients are evenly distributed. A well-designed mixology study is key—sampling at various points and at various mix times will help determine homogeneity.
The formulator must be systematic and thorough, isolating potential problematic variables and carefully evaluating them over time. This kind of upstream investment may extend the development timeline. The back-end return, however, is huge, because it is an opportunity to introduce a bar that is optimal in taste with no stability issues. This results in providing consumers with a positive experience that turns them into loyal customers.
Jones Chan has more than 20 years experience in directing high-performance product development within the food and supplements industry. He was director of R&D at PowerBar from 1998 to 2000 and is currently director of product development for Pharmavite. E-mail: [email protected]