Cocoa or Protein Particles
Most of the milk sold around the globe is homogenized and pasteurized or sterilized. The homogenization process ensures equal dispersion of fat if present It also ensures even dispersion of protein particles which are at or below 1μ in size. Even these tiny particles, however, will settle out eventually, but, generally, the milk will be spoil before this ever happens. Plant based protein, or milks with particles like cocoa have larger particles. The larger the particles, the more quickly they will settle in the bottom of the can or bottle unless the viscosity of beverage is raised. The trick is to increase the viscosity while not changing the refreshing mouthfeel.
Which hydrocolloids are up to the task? For milk systems, carrageenan is a top choice. This is because carrageenan is synergistic with milk proteins. At very low concentrations (0,018%-0,025%), carrageenan forms a 3D network that suspends cocoa while the beverage is at rest. The bonds between carrageenan and milk proteins are weak enough that they will dissipate when drinking giving a light refreshing texture. Because of the protein synergism, carrageenan works best with non-diluted milk such as chocolate milk and many ready-to-serve latte products. It will function in plant-based beverages and dilute milks, but the use level will need to be increased. Even at increased use levels, carrageenan is an economical choice.
Another option that has found a niche within the plant-based beverage market is gellan gum. Gellan gum (high acyl type) forms a fluid-gel network independent of protein content or source. A fluid-gel is practically gelled while sitting on the shelf, but it becomes fluid under the slight shear created by drinking. It is an ideal choice for plant based beverages. Again, use level is very low, usually at around 0,03%-0,035% of gellan gum. It has a very clean mouthfeel. In fact, it is so clean, many manufacturers choose to add a galactomannan such as locust bean gum, guar or tara gum to provide a slight creaminess and add body to the beverage. These galactomannans will also be used at low concentrations; generally less than 0,1%. Of these choices, guar is the most economical even if used at higher addition rates. This is true particularly in the high price current situation for LBG and tara. This system also works well with coffee beverages. If UHT processing is used, a key to remember is to buffer the system well. The pH should never drop below 6.6 for a stable beverage.
Drinking Yogurts, Ambient or Otherwise
Carrageenan works well with neutral pH beverages like chocolate milk, but which hydrocolloids are best for low pH drinks like drinkable yogurt or protein enriched juices? For protein enriched juices, pectin (HM) and CMC are very effective. Both pectin and CMC associate with the protein in low pH conditions to protect it. The hydrocolloid wraps around the protein molecule and keeps the protein micelles from associating with one another. This prevents bridging and flocculation of the protein which would result in a powdery, unpleasant mouthfeel and destabilization of the beverage. Without stabilization, the protein would end up a sludge on the bottom of the bottle with clear fluid on the top.
UHT processing of these proteins can be especially harsh in low pH conditions. Pectin is most useful at the lower end of the pH spectrum for protein fortified fruit juice, at pH 3.6-4.2. For drinking yogurts at higher pH, 4.2 to 4.8, gellan gum (HA type) may be a better choice. Across Asia, drinkable yogurts are UHT processed and usually enjoyed at ambient temperature. These beverages do not contain live active cultures, but remain an excellent source of protein.
Functional Sugar Reduction
Sugar reduction has been a global focus for several years now as obesity rates have increased along with the health issues that come from expanding waistlines. There are a few issues associated with removal of sugar from juice beverages. The first, of course, is loss of sweetness. This can be overcome with the use of high intensity sweeteners from aspartame to Stevia. The second, less well recognized, issue is loss of body or mouthfeel. The mouth is an incredibly sensitive instrument capable of noticing very minute differences in viscosity. The loss of body can take a beverage from satisfying and flavorful to watery and weak with a single sip.
Hydrocolloids offer a variety of solutions. For reduced sugar fruit juices, pectin (a viscosity building HM type) offers a very natural body to the juice. Very low levels (~0,04%) of xanthan gum may be a good solution. Another option is gum acacia which can also double in European markets as an added fiber to the beverage (gum acacia is, surprisingly, not currently recognized as a fiber in the US). Fiber fortification is not only helpful for reducing sugar, fiber has its own halo effect on the finished beverage. While most hydrocolloids are non-digestible and are considered a fiber, most are not used at levels high enough to add much to the fiber content of the finished product, the exception is gum acacia (generally the seyal type). Gum acacia also has other properties that make it invaluable as an ingredient for beverages.
Beverage Flavours Amongst Other Things
Normally, oil and water do not mix. However, the emulsifying grade of gum acacia (senegal type) can make an oil mix with water. This is true for flavour oil such as orange or lemon oil or even a relatively new functional ingredient such as CBD. CBD beverages are cropping up all over the US and Canada where cannabis has been legalized and represents a huge area of opportunity for a variety of hydrocolloids.
Another option for making the oil functional in water is citrus fibre. Citrus fiber has a unique functionality in that oil can be plated directly onto the dry fiber and not spray dried. Citrus fiber has an insoluble portion to it, so a suspending aid like gellan gum is recommended to keep it from settling to the bottom of the beverage.
Boba teas have made a global conquest as Asian flavors and textures become more familiar to western consumers. From simple milk teas with boba or fruit smoothies with boba, these products are nearly everywhere. Boba balls are typically made with tapioca starch and are pretty flavorless on their own, though they soak up the sweetness of whatever beverage they are in. Other textures are possible with other hydrocolloids. Exploding boba made with sodium alginate are popular frozen dessert toppings that could be a fun addition to a beverage. Softer textured, but multicolored balls are possible with low acyl gellan gum. The trick to adding these products to ready-to-drink beverage lies in making certain the colors used are oil soluble, not water soluble. Water soluble colors will bleed into the surrounding beverage more rapidly than an oil soluble one.
Mocktails to Cocktails
Gen Z and millennials are more likely than other generations to enjoy a mocktail, a mixed beverage without alcohol. These may be simple drinks that evoke the flavor of whiskey or gin, or a complicated daiquiri with exotic fruits. Consumers are exploring a wide range of beverage flavors and textures either with or without alcohol. Gum acacia is one of the few hydrocolloids that have no issues with alcohol. Subsequently it is used in crème de menthe, Irish Creams and other liqueurs with cream in the formulation. The creamy coconut of piña colada mixes is often delivered with guar or xanthan gum. Bloody Mary mixes often contain a small amount of xanthan gum to suspend tomato solids and spices evenly throughout the mix.
New Frontiers for Health
Probiotic beverages for health and fun can be found in the new kefirs, drinkable yogurts, kombucha and hard kombucha beverages on offer. The kefir and drinkable yogurts can use pectin or high acyl gellan gum to keep the beverage stable through the shelf-life. Kombucha beverages are considered pro-biotic, but, perhaps new iterations could also contain pre-biotic fibers or hydrocolloids as well. One of the few protein based hydrocolloids, gelatin, is used to create collagen. This ingredient has clinical studies to back up its efficacy as a supplement for bone and skin health. Recent studies indicate collagen plays a role in immune health as well.
With so many options available, consumers could likely have a different beverage every day of the year. Hydrocolloids help formulators achieve novel textures and flavors. They suspend protein and emulsify fats which creates a stable, visually appealing beverage. We conclude, not surprisingly, that “Consumers want it all”, good taste, appealing looks and good nutrition all in one. Nutrition within a balanced diet has become a driving force but consumers do not want to give up any of the features they are used to such as sweet, creamy, filling and refreshing. Beverages have become a versatile channel for nutrition delivery while allowing for a very wide range of differentiated products. Fragmented consumer groups and demands can be addressed by specialized beverage types especially designed to suit those needs. Some will come and go as fads tend to do, but the beverage category as a whole is here to stay and likely to continue its rapid growth for some time.
Nesha Zalesny is co-author of The Quarterly Review
of Food Hydrocolloids, an in-depth analysis
on hydrocolloids, produced by IMR International
since 1991. She has a food science degree, an
MBA and more than 20 years of R&D experience
in food formulations where all types of hydrocolloids