Conversion of Pineapple Peel Residue into Xylooligosaccharides: The Technology Developed by Prof. Wen-Chien Lee from the Department of Chemical Engineering at National Chung Cheng University Increases the Productivity Rate of Xylooligosaccharides
Pineapples are used in the production of pineapple cakes and bromelain. Moreover, pineapple peel residue can be converted into xylooligosaccharides (XOS) that are gastric mucus-friendly and can improve digestion. esiding in the Minxiong Township of Chiayi County, where pineapples are widely cultivated, Prof. Wen-Chien Lee from the Department of Chemical Engineering at National Chung Cheng University (CCU) noticed that large amounts of pineapple peel waste are left after the pineapples are processed. He therefore utilized biotechnology-derived enzymes to decompose pineapple peel residue and to produce XOS, achieving a productivity rate of up to 22%, which is equivalent to producing 220 XOS from one kilogram of pineapple peel residue. A patent application for this technology has been submitted and is currently under review. This new way to utilize pineapple waste can reduce the environmental pollution issues.
“We hope that the whole pineapple, even its waste, can be utilized!” Taiwan abounds with pineapples. The production of pineapple products generates large amounts of pineapple peel waste. According to Prof. Lee, who is among the few Taiwanese scholars to specialize in technologies for producing functional oligosaccharides, local businesses use very little pineapple peel waste as feed; however, such waste consists of 35% hemicellulose, which is a valuable material for XOS production and it would be a pity if it were left unused.
The conversion of pineapple peel into XOS requires only 2-3 days. As stated by Prof. Lee, the CCU team’s patented enzyme was created through the recombination of genes in a strain of alkali-resistant Bacillus. “Pineapple peel was first juiced, dried, pulverized and heat-treated, and subsequently the research team added the enzyme that we developed to initiate a reaction that enabled the conversion of pineapple peel hemicellulose into XOS,” said Prof. Lee. He also commented that, in contrast to the traditional alkalization method applied in local businesses which cannot even achieve a productivity rate of 10%, the productivity rate of XOS from pineapple peel residue reaches up to 22% when the CCU team’s approach is applied. Moreover, the process also generates arabinose that can inhibit the absorption of sucrose and can serve as a multifunctional prebiotic.
“People know about probiotics but do not know that their effects are enhanced when combined with XOSs because XOSs are a raw material used in probiotics.” According to Prof. Lee, who specializes in biotechnologies, XOSs are important prebiotics that can stimulate or activate the growth of gastrointestinal probiotics. In addition to improving gastrointestinal function, XOS can also increase calcium absorption and reduce the risk of colorectal cancer, while having only 40% of the sweetness of granulated sugar. Furthermore, the high pH and heat stability of XOSs allows for their use in low-calorie and diabetes-friendly food, as well as juices and carbonated beverages. Prof. Lee hopes that this biotechnology will facilitate the recycling and re-use of pineapple peel waste, lead to the production of XOSs with high added value, and reduce environmental pollution.
The enzyme developed by the CCU research team has been patented in Taiwan and Japan. The patent application for the technology used to produce XOS from pineapple peel residue has been submitted and is currently under review in Taiwan. It is hoped that this will pave the way for future partnerships with manufacturers. Prof. Lee stated that the developed technology can be also applied to other products that contain high amounts of hemicellulose, such as corn cobs, rice straws, and bagasse.
Prof. Lee has been in the field of biotechnology and chemical engineering research for many years. He is among the few experts in functional oligosaccharides production technologies in Taiwan. According to CCU, his primary areas of research interest include enzyme strains and chemical preparation design. In addition to his research on XOS, Professor Lee also developed a patented technology for producing high-purity isomalto-oligosaccharides. His enzyme-based galacto-oligosaccharides production technology helped manufacturers to establish factories abroad. Prof, Lee also collaborated with international researchers to study inulin and fructooligosaccharides.