Nowadays schoolchildren and university students pay more attention on innovations and are willing to develop novel things which can be used to solve current problems in our day-to-day lives. Our new education system also highly contributes to improve students’ technological knowledge other than theoretical knowledge by introducing new technical subjects and technology facilities. 
“Innovate Sri Lanka 2019” exhibition was a good example. It was organised by the University of Sri Jayewardenapura to celebrate its 60th anniversary of The Innovation Invention and Venture Creation Council (IIVCC). In this educational exhibition, we could see a huge number of innovations and among those novel products, “Carbonate Detector” took a prominent place. This is because much of our food is contaminated with toxic compounds. This is one of the burning issues in our country, since of recent times. 
Most fruit cultivators harvest their produce before the proper maturity stage due to big competition and lack of knowledge regarding proper harvesting practices. As a result, they would lose their profits and to overcome this problem they carry out artificial ripening activities using chemical compounds. In ancient times, the majority of farmers used natural preservative methods to facilitate ripening activities such as smoking, keeping ripened and un-ripened fruits together, spreading unripe fruits over paddy husk or straw etc. However, those ancient methods are not efficient and may destroy the physical appearance of the produce. Therefore, with time they used to discover new artificial ripening methods which feature the use of chemicals such as Carbide and Ethrel. 

Natural ripening Vs artificial ripening

Ripening is a physiological process which makes a fruit edible, palatable and nutritious. General changes associated with the ripening process include softening of the fruit, change in colour and development of characteristic aroma and flavour. And during this process enzymatic breakdown of polysaccharides such as starch into sugar does take place. Usually fruits produce ethylene gas, which is a hormone and helps in the natural ripening of the fruits. 
However, in artificial ripening, unsaturated hydrocarbons such as ethylene and acetylene which are produced by using chemicals speed up the ripening process and cause cosmetic colour changes in fruits to impart them a ripened appearance. The organoleptic properties of the fruits such as taste, physical appearance, smell and softness get impaired comparably with the natural ripening of fruits.  The most commonly used chemical for artificial ripening is Calcium Carbide (CaC2), which is colourless when pure and has carcinogenic properties. When it reacts with water, it produces acetylene gas which is similar to ethylene and accelerates the ripening process.
Calcium Carbide is a dangerous and corrosive chemical and consumption causes several harmful effects to human health such as vomiting, diarrhea with or without blood, a burning sensation in the chest and abdomen, thirst, weakness, difficulty in swallowing, irritation or burning in the eyes and skin, permanent eye damage, ulcers on the skin, sore throat, cough and shortness of breath because it contains a trace of arsenic or phosphorous. In addition it causes an unsettled stomach because the alkaline substance is an irritant that erodes the mucosal tissues in the stomach and disrupts intestinal functions. Moreover, it may affect the neurological system by inducing prolonged hypoxia (low oxygen reaching the blood and tissues) as it contains acetylene gas. 
This is a fate of our food industry and these kinds of unsafe food spoil our health. Every day we spend a huge amount of money to prolong our lives through better nutrition and health management. However, this kind of toxic contaminated food will have a drastic consequences on our lives. Still we don’t have any rapid method to differentiate artificially ripened fruits from naturally ripened fruits. Therefore, this device is beneficial to select healthy fruits available in the market.

Digital carbide detector

A mobile application was developed to detect fruits which were artificially ripened using carbide. This is an innovative tool developed by the students of Food Processing Technology Department of the Faculty of Technology at the University of Jayewardenapura. 
This is a prototype device, which is mainly developed by using the Deep learning model that has manually created neural network system. Here they have used parametres such as surface colour patterns and colour intensity of naturally and artificially ripen “Embul Banana” since there is a different colour intensity in these both these types. Initially, they have optimised this mobile application only for the Embul Banana variety and need to upgrade this app for other fruit types also.

Accuracy

They have done a huge number of lab scale analyses by using approximately 1000 samples which are artificially ripened in the lab using calcium carbide and randomly selected commercially available artificially ripened Embul banana from Jaffna, Kalutara, Gampaha, Ambilipitiya etc. In addition to them, they tested this mobile app by using different kinds of mobile phone types like Samsung, iPhone, Nokia, Oppo etc used in Sri Lanka. And up to this level they could get 75%- 85% accuracy due to the interference that occurred due to environmental factors. An analysis was done by using a concentrated series of calcium carbonate (10 g / 1 kg – 75 g / 1kg).  Black spots like fungus diseases will not interfere with the results of this application since it detects only yellow coloured intensity variations.

Benefits of this applications

This mobile application is user-friendly, rapid, inexpensive and an accurate device.

Further improvements

According to the Principle Coordinator of this Project, Dr. Lanka, they need to further improve and optimise this mobile application via expanding of the data base using approximately 10,000 Embul (sour) banana samples. They have also planned to develop this device for other banana varieties and papaya and mango fruits too.  Other than that they decided to improve sensitivity of the device and reduce the detection time period furthermore. Moreover, they plan to include firmness like new parameters into the mobile application for the detection of carbide presence in fruits other than colour matrix and intensity.  In conclusion the university students are assets for our country as well as to the world and this is a good example. Therefore, our government needs to protect and associate this valuable resource for development of our country by contributing and motivating them to improve their critical thinking ability and creativity. Then as a Nation we   can improve more in the field of technology like in well-developed countries and through that can achieve success in our national production without depending on other imported products.
(Those who were involved in making contributions to the products made by the University of Sri Jayewardenapura for “Innovate Sri Lanka 2019” were Senior Lecturer Dr. Lanka Undugoda, Senior Lecturer Lasanthi Jayathunga, Senior Lecturer Chamila Karunarathna, Mr. Charith Pramodya, Ms. Thilakna Ampemohotti and Ms. Sandali Ranaweera
Ms. Thilini Nayanakanthi, Ms. Sanduni Edirisinghe, Mr. Madumal Weerasuriya, Ms. Divya Rajasekara, Ms. Jalani, Ms. Sudana, Ms. Shakthi, Ms. Tharsika , Ms. Bronija, Dr. Chathuri Senanayaka, Dr. Rumesh Liyanage, Dr. Amali Alahakoon. They are 3rd year Students of Food Processing Technology batch.) 

Pix by Nisal Baduge