• Perspectives
  • 18 September 2020

Researchers use pineapple leaves to extend shelf life of fruits and vegetables

The non-toxic, biodegradable aerogel derived from pineapple leaves can also treat wastewater, absorb oil, and insulate heat and noise, say scientists from the National University of Singapore.

Researchers from the National University of Singapore have found a way to turn pineapple leaves into a biodegradable, non-toxic and ultra-light product that can extend the shelf life of harvested fruits and vegetables by 14 days.

Pineapple leaves are a waste product that is often burnt, landfilled, composted or turned into animal feed after the fruit is harvested. About 27.5 million tonnes of pineapples are harvested each year, and over 76 million tonnes of leaf waste is generated, according to Associate Professor Duong Hai-Minh of NUS’ mechanical engineering department.

Pineapple is grown in tropical countries such as the Philippines, Thailand and Indonesia, and Assoc Prof Duong told reporters on Tuesday (8 September) that the innovation can potentially provide an additional source of income for farmers.

In order to preserve harvested fruits and vegetables, the aerogel is modified with activated carbon powder to take in ethylene gas, which is known as a “fruit ripening hormone” that triggers the ripening of produce.

In lab experiments, the researchers found that the modified aerogels could delay the rotting process of harvested fruit and vegetables by at least 14 days. The aerogels absorbed six times more ethylene than commercial potassium permanganate ethylene absorbents. They are safer than such strong oxidising agents that are conventionally used, and more efficient than non-toxic chemical sprays, said Professor Nhan Phan-Thien, one of the researchers.

The aerogel can also be used for wastewater treatment when coated with a chemical called diethylenetriamine (DETA). This enables it to remove nickel ions in wastewater, and there is potential to extract heavy metals from wastewater when different chemical coatings are applied.

The team began its work in 2016 and has developed aerogels from other agricultural waste products such as sugarcane bagasse, used coffee ground and soy beans. It has also produced aerogels from polyethylene terephthalate (PET) bottles—which are often discarded after a single use—and was the first in the world to produce an aerogel using scrap rubber tyres.

Assoc Prof Duong said he took up the research as aerogels are heralded as a highly promising material with numerous applications, and their market price is high.

His team is working with other entities to commercialise its intellectual property, which could take about two years.

Property developer and manager Mapletree Investments has donated S$155,000 to support the research, and is keen on aerogels for sound and heat insulation in buildings, said Assoc Prof Duong.

His team has signed a research collaboration agreement with a United States-based company called DP Aerogels to work on the fruit preservation and oil-absorption properties of aerogels. Both sides co-own the intellectual property.

The researchers have also licensed the intellectual property for their cotton (fabric waste), plastics and rubber aerogels to DPN Aerogels JSC, a company set up about two years ago with funding from the Vietnamese government. “We also licensed for the company to set up mass production in Malaysia,” said Assoc Prof Duong.

DPN will release its plastics aerogel for sale next year, with the United States, Europe, Australia and Singapore as potential markets. It is looking at a production capacity of one million square metres in the first year. As for the rubber aerogel, it is aiming to produce 100,000 sqm in the first year, he said.

Assoc Prof Duong said another company has expressed interest in acquiring the intellectual property for its aerogels derived from agricultural waste, and is waiting for a pilot project and more tests to be carried out.

This article was first published by Eco-Business on September 9, 2020. The opinions expressed in this publication are those of the author. They do not purport to reflect the opinions or views of Bank of Singapore Limited or its affiliates.


The contents of this article have not been prepared or reviewed by Bank of Singapore Limited (the “Bank”). The Bank is not responsible for the accuracy or completeness of the information contained in this article which may change without prior notice. This article may contain views which are not representative of the views of the Bank, and such views may have been derived without discussion, consultation or agreement with the Bank. You will need to decide as to whether or not the contents are suitable for you. When you are in doubt, please seek your own independent financial, legal, tax or other advice as you deem fit. Neither the Bank nor any of its officers accept any liability for any loss whatsoever arising out of or in connection with your use of the information in the article.

Cross-Border Marketing

Australia: Bank of Singapore Limited (i) is exempt from the requirement to hold an Australian financial services (AFS) licence under the Corporations Act 2001 (Cth) in respect of all financial products or financial services it provides in accordance with ASIC Class Order 03/1102 (as continued in force by ASIC Corporations (Repeal and Transitional) Instrument 2016/396) to any person in Australia who is a wholesale client, and (ii) is regulated by the Monetary Authority of Singapore under Singaporean laws which differ from Australian laws. Brunei: This document has not been delivered to, licensed or permitted by the Autoriti Monetari Brunei Darussalam, the authority as designated under the Brunei Darussalam Securities Markets Order, 2013 and the Banking Order, 2006; nor has it been registered with the Registrar of Companies, Registrar of International Business Companies or the Brunei Darussalam Ministry of Finance. The products mentioned in this document are not registered, licensed or permitted by the Autoriti Monetari Brunei Darussalam or by any other government agency or under any law in Brunei Darussalam. Any offers, acceptances, sales and allotments of the products shall be made outside Brunei Darussalam. Hong Kong SAR: Bank of Singapore Limited is an Authorized Institution as defined in the Banking Ordinance of Hong Kong (Cap 155), regulated by the Hong Kong Monetary Authority in Hong Kong and a Registered Institution as defined in the Securities and Futures Ordinance of Hong Kong (Cap. 571), regulated by the Securities and Futures Commission in Hong Kong. Indonesia: The offering of the investment product in reliance of this document is not registered under the Indonesian Capital Market Law and its implementing regulations, and is not intended to constitute a public offering of securities under the Indonesian Capital Market Law and its implementing regulations. According, this investment product may not be offered or sold, directly or indirectly, within Indonesia or to citizens (wherever they are domiciled or located), entities or residents, in any manner which constitutes a public offering of securities under the Indonesian Capital Market Law and its implementing regulations. Malaysia: Bank of Singapore Limited does not hold any licence, registration or approval to carry on any regulated business in Malaysia (including but not limited to any businesses regulated under the Capital Markets & Services Act 2007 of Malaysia), nor does it hold itself out as carrying on or purport to carry on any such business in Malaysia. Any services provided by Bank of Singapore Limited to residents of Malaysia are provided solely on an offshore basis from outside Malaysia, either as a result of “reverse enquiry” on the part of the Malaysian residents or where Bank of Singapore Limited has been retained outside Malaysia to provide such services. As an integral part of the provision of such services from outside Malaysia, Bank of Singapore Limited may from time to time make available to such residents documents and information making reference to capital markets products (for example, in connection with the provision of fund management or investment advisory services outside of Malaysia). Nothing in such documents or information is intended to be construed as or constitute the making available of, or an offer or invitation to subscribe for or purchase any such capital markets product. Myanmar: The provision of any products and services by Bank of Singapore Limited shall be solely on an offshore basis. You shall ensure that you have and will continue to be fully compliant with all applicable laws in Myanmar when entering into discussion or contracts with Bank of Singapore Limited. Oman: This document does not constitute a public offer of investment, securities or financial services in the Sultanate of Oman, as contemplated by the Commercial Companies Law of Oman (Royal Decree No. 18/2019), Banking Law of Oman (Royal Decree No. 114/2000) or the Capital Market Law of Oman (Royal Decree No. 80/1998) and the Executive Regulations of the Capital Market Law (Ministerial Decision No. 1/2009) or an offer to sell or the solicitation of any offer to buy non-Omani investment products, securities or financial services and products in the Sultanate of Oman. This document is strictly private and confidential. It is being provided to a limited number of sophisticated investors solely to enable them to decide whether or not to make an offer to invest in financial products mentioned in this document, outside of the Sultanate of Oman, upon the terms and subject to the restrictions set out herein and may not be reproduced or used for any other purpose or provided to any person other than the original recipient. Additionally, this document is not intended to lead to the making of any contract within the territory or under the laws of the Sultanate of Oman. The Capital Market Authority of Oman and the Central Bank of Oman take no responsibility for the accuracy of the statements and information contained in this document or for the performance of the financial products mentioned in this document nor shall they have any liability to any person for damage or loss resulting from reliance on any statement or information contained herein Russia: The investment products mentioned in this document have not been registered with or approved by the local regulator of any country and are not publicly distributed in Singapore or elsewhere. This document does not constitute or form part of an offer or invitation to the public in any country to subscribe for the products referred to herein. Saudi Arabia: The Bank has not received authorization or licensing from the Saudi Arabian Monetary Agency or any other governmental authority in the Kingdom of Saudi Arabia to carry on banking business within the Kingdom of Saudi Arabia and the Bank does not hold itself out as carrying on, and does not carry on banking business. South Korea: The document does not constitute an offer, solicitation or investment advertisement to trade in the investment product referred to in the document.  The Philippines: The information contained in this document is not intended to constitute a public offering of securities under the Securities Regulation Code of the Philippines.  Dubai International Financial Center (DIFC): Bank of Singapore Limited has a branch registered in the Dubai International Financial Centre ("DIFC") which is regulated by the Dubai Financial Services Authority (“DFSA”). Bank of Singapore Limited (DIFC Branch) is not a financial institution licensed in the United Arab Emirates outside of the DIFC and does not undertake banking or financial activities in the United Arab Emirates nor is it licensed to do so outside of the DIFC. This material is provided for information purposes only and it is general information not specific in any way to any particular investor, investor type, strategy, investment need or other financial circumstance. As such this information is not financial advice or a financial promotion, nor is it intended to influence an investor's decision to invest. It is not to be construed as an offer to buy or sell or solicitation of an offer to buy or sell any financial instruments or to participate in any particular trading strategy in any jurisdiction. The material is only intended for persons who fulfill the criteria to be classified as “Professional Clients” as defined under the DFSA rules and should not be reviewed, received, provided to or relied upon by any other person. United Arab Emirates (U.A.E): The information contained herein is exclusively addressed to the recipient. The offering of certain products in this document has not been and will not be registered with the Central Bank of United Arab Emirates or Securities & Commodities Authority in the United Arab Emirates. Any products in this document that are being offered or sold do not constitute a public offering or distribution of securities under the applicable laws and regulations of the United Arab Emirates. This document is not intended for circulation or distribution in or into the UAE, other than to persons in the UAE to whom such circulation or distribution is permitted by, or is exempt from the requirements of, the applicable laws and regulations of the United Arab Emirates. The distribution of the information contained herein by the recipient is prohibited. Where applicable, this document relates to securities which are listed outside of the Abu Dhabi Securities Exchange and the Dubai Financial Market.  The Bank of Singapore Limited is not authorized to provide investment research regarding securities listed on the exchanges of the United Arab Emirates which are outside of the DIFC.  United Kingdom: In the United Kingdom, this document is being made available only to the person or the entity to whom it is directed being persons to whom it may lawfully be directed under applicable laws and regulations of the United Kingdom (such persons are hereinafter referred to as ‘relevant persons’). Accordingly, this document is communicated only to relevant persons.  Persons who are not relevant persons must not act on or rely on this document or any of its contents. Any investment or investment activity to which this document relates is available only to relevant persons and will be engaged in only with relevant persons. Relevant persons in receipt of this document must not distribute, publish, reproduce, or disclose this document (in whole or in part) to any person who is not a relevant person.  United States of America: This product may not be sold or offered within the United States or to U.S. persons.

In Hong Kong, Bank of Singapore Limited is a branch of Bank of Singapore Limited incorporated in Singapore with limited liability.

© 2020 Bank of Singapore Limited. All rights reserved.

Version: July 2020