Who doesn’t like the squishy chewy texture of gummy candies in varied shapes, colors and flavors? Takes us down memory lane, and makes us think of a bright summer day or a childhood dream or a gift from our beloved ones. You must be wondering what these little wonders are made of. The basic gummy formulation [1] is comprised of sweeteners (often times a combination of sucrose, corn syrup, dextrose, and sorbitol. Corn syrup prevents sugar crystallization whereas dextrose helps in moisture retention), gelling agents [2] (gelatin, pectin or a combination thereof), citric acid, colors, flavors and polishing agents.
Animal bone and cartilage-derived gelatin are the most widely used gelling agent in gummy candies (although vegan gelatin can be used, it does not require the blooming step), which forms a relatively strong thermo-reversible protein gel with a chewy and elastic texture. Think of gummy bears, peach rings, wine gums and pastilles. On the other hand, when high-methoxy pectin (pectin is a polysaccharide obtained from the skin of fruits and vegetables) is used as a gelling agent in presence of high content acid and sugar, it imparts a softer chewy, tender bite and jelly-like texture to the gummy candies. Examples are fruit gems and jellybeans. Apart from the difference in texture, pectin-based gummy does not melt in a hot environment and offers a better flavor release profile.
The formulation of gummy candies can be very simple if you know how to make it.
The most common problems in manufacturing gelatin-based gummy are:
Sweating and sticking of candies.
Hard candy problem.
Failure to bloom.
Failure to set properly.
Premature setting.
Non-uniform size.
Undesired browning.
Fortunately, with a scientific approach, there is a solution to everything. The shelf-life of gummy candy is mostly dependent on the reducing sugar content, an excess of which may lead to sweating and sticking to the gummy. High humectant content, low polish level, degraded gelatin and insufficient drying may contribute to this problem as well. The best hack is to dip the gummies in ethanol, dry them and then coat them with citric acid before any sugar dusting. If the gummy appears to be too hard, soften them by rehydrating them in a bowl of hot or warm water (not cold water) until the desired consistency is achieved, usually around 20 minutes. During gummy manufacturing, water should be added in a sufficient amount as prescribed, to achieve the desired bloom strength. Failure of gelatin to set properly may be caused by protease enzyme, so avoid using fresh fruits such as kiwi, pineapple, mango and papaya. The premature setting of gelatin may occur due to insufficient processing temperature, 150°F is recommended to keep the gelatin warm. To avoid variation in size, the machine should be set for uniform depositing and molds should be changed particularly if any deformation has occurred. In formulations using beef gelatin (type B gelatin), there is a tendency toward Maillard reaction causing undesired browning (due to reaction between protein and sugar) at the syrup processing temperature of 230°F and above. The solution is to go for pork gelatin (type A gelatin, most widely used in gummy candies) or to use a blend of type A and type B gelatins.
Pectin-based gummy candies have an additional component, some fruit juice. In fact, apples, currants, crab apples, grapes and sour plums may not need added pectin. The major bottleneck in pectin-based gummy candy is to achieve a somewhat chewy texture as it is meant to be jelly-like. The tricks here are to maintain a precise pH of 3.5 during gel setting and not to heat up the pectin-sugar-water mixture beyond 220-240°F, otherwise, the candy may become sticky and caramelized.
Combining gelatin and pectin [3] in the same formulation is another option for achieving optimized texture. The perfect ratio of acid, pectin and sugar is the key to gel formation. So the chosen fruits should be firm and not too ripe (higher pectin content), reprocessing with excess sugar and lime juice may do the trick if the candy has not gelled. If the candy ends up too hard, there is really no fix, so avoid too much pectin and overcooking. To prevent discolouration of pectin gummy during processing, one can use ascorbic acid, which is also a source of vitamin C. Another problem with pectin gummy can be an undesirable cloudy appearance. Pouring the mixture too slowly, allowing the mixture to stand before pouring, not properly straining the juice or pulp and using too green fruits can be the contributing factors, and hence should be avoided.
Be it gelatin gummy or pectin gummy, a few rational and scientific thoughts during manufacturing and post-processing can go a long way, to avoiding common mistakes and achieving a perfect product.
Are you still feeling a little lost?
References
[1] P. Burey et al. (2009). Confectionery gels: a review on formulation, rheological and structural aspects. International Journal of Food Properties 12, 176-210.
[2] T. Dey (2013). Cellulosic oleogel as trans-fat substitute: viscoelastic and structural properties. LWT Food Science and Technology. DOI: 10.1016/j.lwt.2013.07.015
[3] L.L DeMars, G.R. Ziegler (2001). Texture and structure of gelatin/pectin-based gummy confections. Food Hydrocolloids 15, 643-653.
About the Author
Tania Dey has 18 years of post-PhD research experience in various formulation development including gel-based products, lab-based academic research and industrial consultancy.
