Pectinolytic enzymes are one of the important groups of enzymes used in the food processing industry.
What are the most common sources of pectinolytic enzymes?
Pectin enzymes are a group of related enzymes that hydrolyze pectic substances. Pectin is a complex polysaccharide present in the middle lamella of plant cell walls. It is composed of multiple D-galacturonic acid units linked by an alpha-glycosidic bond. Pectin enzymes have been described in higher plants and microorganisms including bacteria and fungi.
Pectin is completely digested by three main enzymes: pectin methylesterase, pectinase, and pectin lyase to release galacturonic acids and their oligomers.
In nature, microorganisms have been endowed with vast potential.
They produce a range of enzymes, which have been commercially exploited over the years. Microbial enzymes have been reported to account for 25% of total global enzyme sales.
Pectic substances can be converted by microorganisms or their enzymes into specific constituent monosaccharides or oligosaccharides without the production of undesirable by-products.What types of pectinolytic enzymes exist, and what are their differences?
Protopectinases: These enzymes degrade the insoluble protopectin present in green fruits, leading to highly polymerized soluble pectin. Pectinosinase is also synonymous with protopectinase.
Pectin methylesterases: These enzymes are responsible for the removal of methoxyl esters, resulting in acidic pectins and methanol. Often referred to as pectin pectylhydrolase, pectinesterase, pectase, pectin demethoxylase, and pectolipase, it is a carboxylic acid esterase and belongs to the group of hydrolase enzymes.
Fungal pectin methylesterase acts via a multi-chain mechanism, randomly removing methyl groups. In contrast, plant pectin methylesterases tend to act at the non-reducing end or next to a free carboxyl group and progress along the molecule via a single-chain mechanism.
Polygalacturonases: These are pectinolytic enzymes that catalyze the hydrolytic cleavage of the polygalacturonic acid chain in the presence of water. They are the most studied among the pectinolytic enzyme family. Polygalacturonases are classified into two types: endopolygalacturonase and exopolygalacturonase.
Endopolygalacturonase hydrolyzes polygalacturonic acids and releases oligogalacturonic acids. Exopolygalacturonase hydrolyzes pectic acids and releases monogalacturonate.
Pectin lyases: Lyases (or transeliminases) perform non-hydrolytic breakdown of pectates or pectinates, characterized by a transeliminative cleavage of the pectic polymer. Lyases break the glycosidic bonds at the fourth carbon and simultaneously remove hydrogen from the fifth carbon, producing an unsaturated product.
Polygalacturonate lyases (pectate lyases) are produced by many bacteria and some pathogenic fungi, with endopolygalacturonate lyases being more abundant than exopolygalacturonate lyases. Polygalacturonate lyases have been isolated from bacteria and fungi associated with food spoilage and soft rot.
They can be classified into four types based on their action pattern: endo-polygalacturonate lyase, exo-polygalacturonate lyase, endo-polymethylgalacturonate lyase, and exo-polymethylgalacturonate lyase.What are the main applications of pectinolytic enzymes in the food industry?
Manufacturing important industrial products by using enzyme technology is a sustainable method and has much to offer compared to the use of chemical catalysts. The enzyme can manage industrial preparation under mild reaction conditions using a specific substrate.
The enzyme uses a shorter time, produces limited or no waste, and is eco-friendly in nature. The complex pectinase enzyme system catalyzes the breakdown of pectin polymers. Pectinases are known for their tremendous potential in various industries.
Use in food products
Pectin has been used in various industrial processes and applications due to its biocompatibility, cost-effectiveness, easy availability and presence among the most abundant natural compounds on Earth. Major applications of pectin in industries are food additive, thickening agent, gelling agent, cosmetic texturizing agent, good source of dietary fiber and also components of biodegradable films, adhesives, paper and antimicrobial food packaging.
Pectin methylesterase and endopolygalacturonase have important role in fruit softening, juice extraction and clarification, gel preparation, food manufacturing, olive oil extraction etc. Galacturonic acid, is used for production of vitamin C as an acidic agent in food industries and as a detergent agent in chemical industries.
Almost all commercial preparations of pectinases are produced from fungal sources. Filamentous fungi, especially Aspergillus niger, are the main producers of acid pectinases, mainly used in the fruit juice and wine industries.
Pectinolytic enzymes in the food industry
It has been widely used in the fruit and vegetable juice industries. These industries commercially produce different juices including clear, sparkling juices, cloudy juices, and single-cell products. In sparkling clear juices, pectinase is added to enhance juice yield by hydrolyzing pectin particles.
They also have an important role in the fermentation of tea and coffee. In addition to increasing tea fermentation, pectinase also destroys the foamy character of instant tea powder by degrading pectin.
Pectinase is very important for sustainable industrial processes and can be applied in different industrial applications. It catalyzes the decomposition and modification of pectin-based substances by hydrolysis, transelimination, and deesterification reactions.
Pectinase can be obtained from different organisms, and microorganisms are usually used for industrial pectinase production. Microbial pectinases have enormous applications in different industries and are among the most important industrial enzymes that play an important role in today’s biotechnological world.
Do you want to receive more information about trends in Ingredients in your email?
Access exclusive content only for community members
Join our exclusive membership for industry professionals in food, beverage, and dairy ingredients. Access strategic information, emerging trends, networking, and personalized resources to boost your professional development and the success of your company.
