What Is Hydrocolloid？
Hydrocolloids are molecules that have a high affinity for water and can form thick gels in water. Hydrocolloids can be derived from various natural sources such as plants (e.g. pectin, guar gum), animals (e.g. gelatin), and microbial sources (e.g. xanthan gum). They can also be modified chemically to suit specific applications. Hydrocolloids are used in a wide variety of industries, most commonly in food and cosmetics.
Hydrocolloids are extensively used in the food industry for various purposes, such as thickening, stabilizing, emulsifying, and gelling. They enhance the texture, mouthfeel, appearance, and shelf-life of food products. Some common hydrocolloids used in the food industry include guar gum, xanthan gum, carrageenan, pectin, and agar.
Hydrocolloids play a significant role in the cosmetics industry. They improve the viscosity, texture, and stability of cosmetic products. Some common hydrocolloids used in the cosmetics industry include cellulose gum, hydroxyethylcellulose, and carbomer.
What's New About Applications of Hydrocolloids?
In addition to the common applications mentioned above, here we pay more attention to innovative applications of hydrocolloids, such as drug delivery, 3D food printing, and biodegradable materials.
l Hydrocolloids in Drug Delivery Applications
Hydrocolloids have been increasingly studied in the fabrication of nanocarriers for controlled and targeted drug delivery, most likely due to their low toxicity, biocompatibility, and excellent biological properties. Nanocarriers can prevent drug degradation, improve encapsulation efficiency and pharmacokinetic aspects of drug molecules. In the pharmaceutical field, many hydrocolloids such as guar gum, carrageenan, xanthan gum, gum arabic, and pectin, etc. have shown the potential to protect drugs from external stressors, to name a few:
Chitosan, the only positively charged polysaccharide, ranks high on the list of natural polymers used in drug delivery systems due to its versatility and non-toxicity. For example, it can serve as an excellent drug carrier using folic acid, especially for targeting colorectal cancer.
Polymer-based nanocomposites in combination with oppositely charged polyelectrolytes, such as chitosan/α-lactalbumin and bovine serum albumin/kappa-carrageenan, have been successfully used in the fabrication of edible nanotubes to achieve efficient drug delivery.
l Applications of Hydrocolloids in 3D Food Printing
The new 3D printing technology has been widely used in many kinds of food research and processing, which is suitable for personalized food design and small-scale food production. In 3D food printing technology, the properties of the food matrix such as consistency, viscosity and solidification characteristics must be considered. It has been demonstrated that the suitability of soy protein isolate (SPI) for 3D printing can be improved by adding sodium alginate and different concentrations of gelatin.
l Hydrocolloids As Alternatives to Non-Biodegradable Materials
In order to combat the harmful effects of non-biodegradable materials, the possibility of hydrocolloids being used to replace petroleum-based materials is being explored and discovered, which may contribute to the food industry and environmental sustainability. Although natural hydrocolloids suffer from low mechanical strength, flexibility issues, and polymer diffusion, hybrid combinations can overcome these issues and be modified as needed. Blending natural hydrocolloids with different properties has been considered as a new alternative to modify the properties of natural hydrocolloids and create novel smart food packaging with desirable properties compared to the individual components. For example, the development of packaging films mixed with various natural hydrocolloids, such as agar, carrageenan, pectin, alginate, etc., has been investigated by exploiting their physical properties and/or their interactions to improve packaging performance.
References
1. Jingwang Chen, et al. Journal of Food Engineering, 2019, 261, 76-86.
2. Mehnaza Manzoor, et al. International Journal of Biological Macromolecules, 2020, 165, 554-567.
3. Bhawna Bisht, et al. Critical Reviews in Food Science and Nutrition, 2020, 62, 693-725.
