Adjouman Yao Desire is a 3rd year PhD student and currently he is at the University of Liège Gembloux Agro-Bio Tech to complete his research and to complete his thesis at laboratory of Quality, Security products Agro-Food of the said University. He has completed his Masters in Science and Technologies of Food Biochemistry and Food Technology option.
A study in Côte d'Ivoire entitled "artisanal and industrial valorization of native cassava (Manihot esculenta Crantz) and yam (Dioscorea spp)" starches showed that the film produced with 4% starch cassava and 5% vegetable oil showed the most promising coatings capabilities. This film was designed without plasticizer and showed mechanical limits. So, the presence of plasticizer could overcome the fragility of the film, with a commonly used slurry of 15-40/g of glycerol in 100 g of starch. The properties of starch films can be further improved by producing composite films with incorporation of functional additives. Thus, in this present study, starch-based films have been strengthened with addition of a plasticizer (glycerol), an emulsifier (soy lecithin) and a preservative (potassium sorbate). These mixture led to produce biodegradable edible packaging based on native starches extracted from improved cassava varieties in Côte d'Ivoire. This study is currently carried out at the University of Liege, Gembloux Agro-Bio Tech laboratory Quality and Product Safety Agro-Food. The optical, mechanical and water vapor barrier properties of the starch-based films containing 4% to 5% vegetable oil, glycerol (0, 15, and 25%), soybean lecithin (0 to 5%) and potassium sorbate (0 to 2 g) are investigated. The effectiveness of the optimal formulation for uses as coating of raw food crops (cassava roots, fruits and vegetables) and production of biodegradable packaging will be studied.
Inyoung Choi received her Bachelor’s degree in the Department of Food and Nutrition from Korea University. Currently, she is pursuing her master’s degree in the Department of Food Bioscience and Technology from Korea University. Her recent research focuses on the development of smart packaging materials with a reliable indicator technology.
Intelligent packaging and active packaging are newly developed concepts in modern food packaging system. Colorimetric pH indicator can be used as a part of the intelligent food packaging system to detect quality changes in food. In this study, potato starch and agar, which are natural and good film forming agents, were used for immobilizing natural dyes extracted from purple sweet potato, Ipomoea batatas to prepare a colorimetric pH indicator film. This anthocyanin extract was mixed in potato starch and agar solution as a natural pH dye. The film-forming solution was casted to make a dried indicator film. The color of pH indicator film changed from red to green after exposure to different pH solutions in the range of pH 2.0-10.0, since anthocyanin extract changed its color from red to green according to the pH variations. The UV-VIS spectra of the anthocyanin solution showed the color variation according to the different range of buffer solutions. Spectroscopy of Fourier Transform Infrared spectroscopy (FT-IR) and UV-visible region showed the compatibility between the polymers and natural dyes. The color variation of the pH indicator film was measured by colorimeter after activation in different pH buffers. Application test was conducted to validate the pH indicator film as a meat spoilage sensor. As a result, the color of pH indicator changed from red to green due to the pH increase under improper storage conditions. The result implied that the developed indicator film can be applied to intelligent food packaging system as a food spoilage indicator.