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Bringing Science to the society - IISc develops innovative technologies for quality assessment of Silk and Milk

  • Photo: Prasobhkumar PP / OMI Lab, IISc

Photo: Prasobhkumar PP / OMI Lab, IISc

India’s rapid growth in science and technology has taken it to the third spot among the most attractive investment destinations for technology transactions in the world and is among the topmost countries in the world in the field of scientific research. But one of the criticisms among the general public has been in the failure of advancements in science and technology translating into usable inventions.

Now, a few researchers at the Indian Institute of Science (IISc), Bangalore, have tried to put these criticisms to rest by developing technologies that positively impact our lives. As a testimony to this, two such innovations from the Optics and Microfluidics Instrumentation (OMI) Lab have won the recently announced Gandhian Young Technological Innovation (GYTI) Award by the Society for Research and Initiatives for Sustainable Technologies and Institutions (SRISTI), a developmental voluntary organization, and Biotechnology Industry Research Assistance Council (BIRAC).

One of these innovations is a portable device that checks for defects in silk cocoons, thus helping farmers and silk weavers in selecting the best cocoons for producing silk. Another is the development of a device to measure the amount of melamine, a chemical added in milk to increase its apparent protein content. This would help tackle the rampant problem of adulteration of milk. The researchers at the OMI lab work on two fields of science - Optics and Microfluidics. Optics is the study of light and its properties like reflection and diffraction, while microfluidics is the study of tiny amounts of fluids, in the range of microlitres (one millionth of a litre) flowing in minuscule pipes of sub millimetre scale. “In general, our lab is interested in developing variety of instruments based on optics annd microfluidics that have applications in healthcare,  quality control, blood tests, water quality tests, adulterant detection and so on”, says Prof. Sai Siva Gorthi, an Assistant Professor at the Department of Instrumentation and Applied Physics at IISc, and the head of the OMI lab.

Detecting melamine in milk

Melamine is a compound generally used in manufacturing a type of plastic (melamine-formaldehyde) resin. Due to its high Nitrogen content, melamine can increase the apparent protein content of food substances, especially milk, making it a widely used adulterant. The adulteration was at its peak in 2008 when, in China, close to 300,000 victims, mostly infants, suffered due to milk and an infant formula that had been adulterated with melamine. An excess of melamine in the body could lead to kidney stones and other renal problems. Today, although strict regulations try to protect us from such misfortunes, adulteration still persists.

Researchers at the OMI lab, S. Varun,  Dhiraj Indana, Prateek Katare and Dr. S.C.G. Kiruba Daniel recognized the need for preventing such disasters in future. “We have built a device that uses nanotechnology to detect melamine in milk”, says Mr. Varun excitedly, which was guided by Prof. Gorthi. “Conventionally, sophisticated instruments like a chromatographer are used to detect melamine, which farmers and those outside of laboratories do not have access to. But using our device, one can detect the adulteration easily using the colour change that occurs when melamine is present in milk, which can be read by an optical reader built by us”, he adds.

The researchers have exploited the process by which melamine affects the formation of silver nanoparticles, in developing their optical reader. “The optical device has reagents that react to form silver nanoparticles, which usually appears yellow. When melamine is present in milk, the formation of nanoparticles is disrupted and the reagents appear a different colour. Now, by analyzing the change in colour, the optical device can even tell us the concentration of melamine in units of parts per million (ppm)”, explains Mr. Prateek Katare.
This innovation was awarded under the ‘Socially Relevant Innovation’ category, and includes Rs. 15 lakhs grant for taking their innovation to the market place. 

Robots to assess quality of Silk Cocoons

Silk is a natural fibre extracted from the cocoons of silk moths. The process of extraction requires selecting cocoons without defects which are then boiled to extract silk. Although India ranks second as the largest producer of silk, this critical process of assessing the quality of the cocoons is still done manually. Either the farmer who grows cocoons, or the dealer who purchases it, randomly selects a few cocoons from each batch, looks for visible defects using their eyes or by shaking the cocoon. This process leads to large number of defective cocoons still being mixed with the good ones, thus affecting the quality of the silk fibre.  To produce the best quality of silk, each cocoon needs to be tested, making it labour intensive and time consuming. Mr. Prasobhkumar P. P., a doctoral researcher at the OMI lab was approached with the idea of developing a robot for testing cocoon quality, by Prof C R Francis, a Professor at the Department of Sericulture at Maharani’s Science College for Women.

“There are two reasons I got interested in this” says Prof. Francis “Firstly, In India, the cocoons are sold in an auction. Here, due to a lack of quality based pricing, either the dealers are affected by buying a lot of defective cocoons or the farmers are affected who sell the cocoons at a low price, due to the presence of defective cocoons. And second reason is, due to various factors, like the climate, rainfall, humidity, etc., many of the cocoons gets damaged and a farmer has no way of knowing if something is happening to his cocoons or what’s causing the problem. If the process of assessment is automated, both farmers and the dealers will be happy about the quality. But more than that, farmers can now test the quality of the cocoons as they grow and change factors like temperature and humidity to get a better yield”, he adds. 

Mr. Prasobhkumar, under the guidance of Prof. Gorthi, developed the optics hardware system along with the software that could take each image containing about 96 cocoons and assess the quality of each of them in less than a second. “We developed the image processing algorithm to detect the defects based on size, shape, colour and the position of the defect. Based on these four parameters and a set of 5 different templates of different types of good cocoons, the handheld system displays which type the defective cocoons are, besides what their number and percent are” explains Mr. Prasobhkumar.

The researchers have also built an audio based detection system where the cocoon is vibrated  using a  robotic arm and a microphone attached to it, picks up the impact acoustic emissions made by the pupa as it hits the wall of the cocoon. Based on the sound, the software decides the quality of the cocoon. This innovation was awarded the GYTI appreciation award under “Cutting Edge Innovation” category.

The researchers are ambitious about the future of this innovation. “As a next step, we want to automate the whole process, by making a conveyor belt where the cocoons move, and a camera will take pictures. Next, the cocoons are made to roll down, while a microphone will listen to the sounds it produces. Based on the texture, shape and sounds, we can have a real-time quality assessment system for cocoons, which will boost the Indian silk market enormously” signs off Prof. Francis.
Here is wishing the teams all the best for their endeavours!