Featured Research

from universities, journals, and other organizations

Revealing the ancient Chinese secret of sticky rice mortar

Date:
June 1, 2010
Source:
American Chemical Society
Summary:
Scientists have discovered the secret behind an ancient Chinese mortar made from sticky rice, that delicious "sweet rice" that is a modern mainstay in Asian dishes. They also concluded that the mortar -- a paste used to bind and fill gaps between bricks, stone blocks and other construction materials -- remains the best available material for restoring ancient buildings.

Construction workers in ancient China used sticky rice to make a super-strong mortar for city walls (right) and other structures that even withstood earthquakes. Chemists now have discovered the ingredient in sticky rice that made the mortar so strong.
Credit: iStockphoto/Hippo Studio

Scientists have discovered the secret behind an ancient Chinese super-strong mortar made from sticky rice, the delicious "sweet rice" that is a modern mainstay in Asian dishes. They also concluded that the mortar ― a paste used to bind and fill gaps between bricks, stone blocks and other construction materials ― remains the best available material for restoring ancient buildings.

Their article appears in the American Chemical Society (ACS) monthly journal, Accounts of Chemical Research.

Bingjian Zhang, Ph.D., and colleagues note that construction workers in ancient China developed sticky rice mortar about 1,500 years ago by mixing sticky rice soup with the standard mortar ingredient. That ingredient is slaked lime, limestone that has been calcined, or heated to a high temperature, and then exposed to water. Sticky rice mortar probably was the world's first composite mortar, made with both organic and inorganic materials.

The mortar was stronger and more resistant to water than pure lime mortar, and what Zhang termed one of the greatest technological innovations of the time. Builders used the material to construct important buildings like tombs, pagodas, and city walls, some of which still exist today. Some of the structures were strong enough to shrug off the effects of modern bulldozers and powerful earthquakes.

Their research identified amylopectin, a type of polysaccharide, or complex carbohydrate, found in rice and other starchy foods, as the "secret ingredient" that appears to be responsible for the mortar's legendary strength.

"Analytical study shows that the ancient masonry mortar is a kind of special organic-inorganic composite material," the scientists explained. "The inorganic component is calcium carbonate, and the organic component is amylopectin, which comes from the sticky rice soup added to the mortar. Moreover, we found that amylopectin in the mortar acted as an inhibitor: The growth of the calcium carbonate crystal was controlled, and a compact microstructure was produced, which should be the cause of the good performance of this kind of organic-organic mortar."

To determine whether sticky rice can aid in building repair, the scientists prepared lime mortars with varying amounts of sticky rice and tested their performance compared to traditional lime mortar. "The test results of the modeling mortars shows that sticky rice-lime mortar has more stable physical properties, has greater mechanical strength, and is more compatible, which make it a suitable restoration mortar for ancient masonry," the article notes.


Story Source:

The above story is based on materials provided by American Chemical Society. Note: Materials may be edited for content and length.


Journal Reference:

  1. Fuwei Yang, Bingjian Zhang, Qinglin Ma. Study of Sticky Rice-Lime Mortar Technology for the Restoration of Historical Masonry Construction. Accounts of Chemical Research, 2010; 100510131945076 DOI: 10.1021/ar9001944

Cite This Page:

American Chemical Society. "Revealing the ancient Chinese secret of sticky rice mortar." ScienceDaily. ScienceDaily, 1 June 2010. <www.sciencedaily.com/releases/2010/05/100530093704.htm>.
American Chemical Society. (2010, June 1). Revealing the ancient Chinese secret of sticky rice mortar. ScienceDaily. Retrieved July 30, 2014 from www.sciencedaily.com/releases/2010/05/100530093704.htm
American Chemical Society. "Revealing the ancient Chinese secret of sticky rice mortar." ScienceDaily. www.sciencedaily.com/releases/2010/05/100530093704.htm (accessed July 30, 2014).

Share This




More Fossils & Ruins News

Wednesday, July 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rodents Rampant in Gardens Around Louvre

Rodents Rampant in Gardens Around Louvre

AP (July 29, 2014) Food scraps and other items left on the grounds by picnickers brings unwelcome visitors to the grounds of the world famous and popular Louvre Museum in Paris. (July 29) Video provided by AP
Powered by NewsLook.com
London's Famed 'Gherkin' Goes on Sale for 650 Mln

London's Famed 'Gherkin' Goes on Sale for 650 Mln

AFP (July 29, 2014) London's "Gherkin" office tower, one of the landmarks on the British capital's skyline, went on sale for about 650 million ($1.1 billion, 820 million euros) on Tuesday after being placed into receivership. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Tourists Disappointed to Find Rome Attractions Under Restoration

Tourists Disappointed to Find Rome Attractions Under Restoration

AFP (July 26, 2014) Tourists visiting Italy at the peak of the summer season are disappointed to find some of Rome's most famous attractions being restored and offering limited access. Duration: 01:01 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins