Innovation nation: Tips for developing liquid nutraceuticals

Editor's note: This column is part of an "Innovation nation" series of articles on formulating innovative dietary supplement products.

The liquid nutraceuticals market is a growing and challenging product development category. For many dietary supplement companies, a natural progression is to diversify into developing liquid nutraceuticals.

My experience with liquid nutraceuticals started in the 1980s with dropper bottle formulations and expanded into all types, including working for a major liquid nutraceuticals product contract manufacturing company, Celmark International Inc. Many new challenges exist when creating liquid nutraceuticals, including FDA compliance, nutrient composition, digestion and achieving the most desirable sensory profile characteristics.

Figure 1. Ideation/Planning – Product Development – Manufacturing – And More

Image source: Food Innovation Center at Rutgers

Liquid nutraceuticals

From a consumer perspective, liquid nutraceuticals have much appeal and are compatible with line extensions to conventional dietary supplements. But developing and making liquid nutraceuticals inherently comes with challenges, such as mastering flavor and other sensory profile properties; formulating using the right ingredients; investing time, money and other resources into other areas of development, including stability testing; establishing distribution; and entering a business with a high rate of failure. All of these considerations collectively pose potential adverse consequences to the main supplement business.

Related:Innovation nation: Smart approach to dietary supplement formulation

From a nutrition science perspective, liquid nutraceuticals offer many advantages. Some of them include:

- Consistent bioavailability.

- Fast acting.

- Accommodate larger nutrient amounts.

- Easy to swallow.

- Use during exercise and athletic events.

- Overcome “pill-taking fatigue.”

FDA’s guidance: Why it is important reading

In 2014, FDA published “Guidance for Industry: Distinguishing Liquid Dietary Supplements from Beverages.” This is essential reading for everyone involved with liquid nutraceuticals.

Will your beverage be labeled with Nutrition Facts or Supplement Facts? This FDA guidance provides insights about how this labeling decision impacts the ingredients that can be used, nutrition product identity statements, product use claims, efficacy claims, type of packaging/containers, and more regulation compliance issues.

The guidance explains that a dietary ingredient that is lawful for addition to dietary supplements may or may not also be lawful for addition to conventional foods, which includes beverages. Therefore, it is the responsibility of each company to determine the legal status of ingredients being used in their Nutrition Facts or Supplement Facts labeled liquid nutraceutical products. This includes the nutritive active ingredients/dietary ingredients and the variety of non-nutritive food additives being used, artificial sweeteners, and flavors and colors, for example.

If there is uncertainty about the legal status of an ingredient after checking the code of federal regulations and FDA’s website databases, I suggest contacting: the ingredient companies; a food lawyer, consultant or other qualified professional; and the appropriate FDA office to confirm that the ingredients you are using have legal status for use in conventional foods/beverages and dietary supplements during the initial new product development stage. Depending on the type of ingredients, you may even determine if it is a new dietary ingredient or new food additive, for example, requiring notifications to the FDA or authorization.

Energy drinks

Making the body perform better physically and mentally are top reasons people are using energy drinks. What do most consumers expect when purchasing an energy drink? Delicious flavor and immediate benefits are on the top of the list. Here is a summary of some of the types of energy drink ingredients being used.

- Water for quenching thirst and maintaining body hydration levels for health and physical activity. For athletic people during sports or working, physical performance decreases as the body becomes dehydrated, and keeping adequately hydrated is a top daily nutrition goal for everyone.

- Energy substrates. Some energy drinks contain calories while others contain none. When containing calories, carbohydrates tend to be the main ingredients and include glucose, sucrose, fructose and different types of complex carbohydrates. Using higher amounts of complex carbs can be appealing for people who are avoiding added sugars, including sucrose and fructose. Also consider using a variety of “short chain” complex carb options that are fast digesting, in addition to simple carbs. Additionally, fatty acids, in particular MCTs (medium-chain triglycerides), as well as amino acids/proteins, are being used in some energy drinks.

- Stimulants, with clinical research-proven caffeine being the top active ingredient. Various plants containing caffeine are common, such as guarana (P. cupana), yerba mate (I. paraguariensis), tea (C. sinensis), coffee (C. arabica/canephora) and cocoa/cacao (T. cacao). However, from an efficacy and manufacturing QC (quality control) point of view, synthetic and natural purified caffeine ingredients may have advantages over non-purified plant source ingredients. 

- Electrolytes are minerals with electric charges when dissolved. Examples of the major electrolytes being used in energy drinks include calcium, chloride, magnesium, phosphate, potassium and sodium. Don’t overdo the electrolytes!

- Energy metabolism production nutrients and substances, such as B vitamins and carnitine.

- Additional ingredients. When evaluating the use of additional ingredients, ask whether they are helping to promote physical and mental performance or another benefit, or just being used for increasing perceived value. Some of these additional ingredients used in energy drinks for physical and mental performance include beta-alanine, Siberian ginseng (E. senticosus), Asian ginseng (P. ginseng), American ginseng (P. quinquefolius), choline, taurine, acetylcarnitine, bacopa (B. monnieri), citicoline, ginkgo, phosphatidyl serine, rhodiola (R. rosea), L-tyrosine, ashwagandha (W. somnifera) and schisandra (S. chinensis).

Stomach-emptying rates can matter

Often overlooked is how fast or slow the liquid nutraceutical will empty from the stomach and if this is important for the intended use. Solute concentration is an energy drink attribute that needs to be considered concerning the relationship with stomach-emptying rates. Having more solutes in a drink — meaning the more concentrated it is — may slow down the rate of digestion. As a general rule, a more concentrated drink will usually result in a slower stomach-emptying rate.

Composition of ingredients can also contribute to slowing down the rate of stomach emptying. For example, when protein and fatty acids are included in sufficient amounts, this may increase the time it takes to pass through the stomach into the intestines. The stomach-emptying rate is more of a concern when consuming energy drinks before and during exercise, athletic events and physical work. While fast absorption of nutrients and other types of dietary ingredients is a main purpose of liquid nutraceuticals, be aware when certain ingredients such as stimulants are contained in high amounts and the product is consumed too fast, some people have reported experiencing various side effects, including gastrointestinal upset and overstimulation, for example.

Characteristics such as osmolarity and tonicity should be evaluated during product development to ensure the intended performance-enhancing goals are not impaired. A variety of published reference values can be used as starting points, mostly related to energy drinks during exercise and medical nutrition therapy. Ideally, each energy drink can be clinically tested to determine average stomach-emptying/digestion, absorption, utilization and effectiveness of the intended uses.

Sensory profiling

Another complex topic deserving of a series of articles is sensory profiling. Sensory profiling is a complex but essential process in the food and beverage industry. It combines scientific methods with human perception to create products that not only meet and maintain quality standards in production, but also satisfy consumer preferences, expectations and acceptance. From a competition standpoint, many companies are leveraging sensory profiling to innovate and improve their products.

While sensory attributes are important when developing and making solid dose supplements, they are simpler compared to beverages, whose characteristics have a distinct look, aroma and ease of consumption. When sensory factors like flavor/taste, aroma and mouthfeel come into play, product development gets more challenging.

Another point regarding sensory profiling is the need to establish specifications to ensure consistency for each production run. This is mandatory for providing consumers with a consistent product, but also since many retailers are conducting their own sensory profile evaluations when receiving these types of health products to confirm consistency, which may become a reason for rejecting deliveries. 

Sensory profiling is a comprehensive evaluation encompassing various aspects of the liquid nutraceutical beverage experience, including:

- Appearance — The visual aspects that play a significant role in consumer perception, including color, clarity and any visual textures or particulates.

- Aroma — The olfactory experience from aroma compounds and their intensities.

- Flavor/taste — The basic taste sensations (sweet, sour, salty, bitter, umami) as well as more complex flavor notes.

- Mouthfeel/texture — Physical sensations when consuming a drink, which can include viscosity, feel such as creaminess, carbonation, chemical effects such as astringent, mouthcoating, after-feel, hot/cold and wet/dry feelings.

Also, a variety of sensory analysis methods are used by trained and qualified sensory experts.

- Descriptive analysis — Experts use standardized terminology to describe and quantify specific sensory attributes.

- Difference testing — Methods are used to determine if consumers can detect differences or similarities between samples, like with triangle testing in which assessors receive a set of three samples.

- Hedonic scale testing — Measuring levels of pleasure or liking a product with interpretations ranging from dislike extremely to like extremely.

- Just about right scale (JAR scale) testing — Evaluating the appropriateness of characteristics such as saltiness or sweetness, with interpretations ranging from too low to just about right or too high.

- Preference testing — Consumers rate their liking or preference of different samples.

- Quantitative/statistical analysis — Scoring systems developed to quantify sensory attributes and used when reporting the sensory evaluation findings.

Based on the overview above, it is easy to appreciate the need for a team of sensory experts during the development and production of liquid nutraceuticals. A sensory profiling team can include in-house experts, ingredients suppliers, trained tasting panelists, consumer market research, and product development contractors offering some of or all of the required sensory profile development and evaluation services. For example, food and beverage development companies like the Food Innovation Center at Rutgers can increase the chances of new product success.

Hard liquid-filled capsules

When developing liquid nutraceuticals with smaller dosages like tablets, capsules and softgels, hard liquid-filled capsules are gaining increasing market share and attention from consumers. Charles Mooney, president of NutraSeal and a nutraceuticals industry veteran, offered me some input about key advantages associated with using hard liquid-filled capsules that dietary supplement product development experts are interested in. These include.

- Suitable for liquid rapid-release formulas.

- Consistent bioavailability.

- Content uniformity.

- Hard capsule material options, including vegan.

- Hard capsules offer protection for oxygen-sensitive ingredients.

- Can accommodate a higher diversity of ingredients than softgels and solid dosages.

- Improved masking of odorous and bad-tasting ingredients.

- Can manufacture small production runs.

- High perceived value.

- Branding options from a range of capsule color selections, banding and imprints.

Source: https://nutraseal.com

In conclusion, dietary supplement companies interested in liquid nutraceuticals have a variety of options and stakeholders to work with to increase their chances of successfully diversfying into new product categories. In addition to working with contract manufacturers or using in-house capabilities, one tip is to include a top food and beverage development and pilot manufacturing company on your team, such as the Food Innovation Center at Rutgers.