Protein is an essential nutrient for humans to sustain life, but it is predicted that it will be challenging to secure protein through the traditional livestock industry in the future. Microalgae has high future value as an alternative protein food source due to resource utilization and sustainability advantages. In order to increase productivity, the culture conditions of microalgae, Chlorella vulgaris, Dunaliella salina, and Scenedesmus obliquus were examined in this study. The optimal culture conditions of C. vulgaris were mixotrophic culture, 25oC culture temperature, 7.0 initial pH, 10% initial inoculation, stirring culture, 3000 Lux light intensity, and 24L:0D light/dark cycle period with red LED. For D. salina, the optimal culture conditions were mixotrophic culture, 20oC culture temperature, 8.0 initial pH, 10% initial inoculation, stirring culture, 6000 Lux light intensity, and 12L:12D light/dark cycle period with white LED. For S. obliquus, the optimal culture conditions were mixotrophic culture, 30oC culture temperature, 8.0 initial pH, 10% initial inoculation, stirring culture, 4500 Lux light intensity, and 14L:10D light/dark cycle period with fluorescent light. These findings can be used as important information for increasing the production of microalgae as an alternative protein material resource in the future.

This study was carried out to examine the physical characteristics of bacterial cellulose (BC) and its optimal culture condition using coffee by-products. Recently, recycling resources and employing eco-friendly materials have been raised as significant issues in the food industry. As the coffee industry develops, interests and efforts for recycling coffee wastes are also growing. This study attempted to confirm the production of BC by utilizing spent coffee grounds filtrate as a medium. In order to confirm the optimal culture conditions for BC production, different culture methods, initial pH, culture temperature, and culture period were examined. The optimal pH and temperature were 6.0 and 30oC, and the optimal culture period was 14 days. The cultivated BC was dried by hot air drying, freezedrying, and mold drying, respectively. Then, the properties of the BC films, such as tensile strength, elongation, water-solubility, thickness, and chromaticity were compared. The drying method affected the shape and structure of the final BC films. The production of BC film is expected to expand opportunities for recycling coffee by-products and contribute to solving environmental problems caused by food waste.

As coffee consumption increases, coffee extraction's by-products increase. Research on coffee by-product recycling is fundamental as social costs and environmental problems arise from the course of coffee processing, estimated to be 270,000 tons per year. This study attempted to confirm the possibility of an eco-friendly food packaging material by solvating cellulose from spent coffee grounds. For cellulose solubility, delignification and TEMPO (2,2,6,6- tetramethylpiperidin-1-oxyl) oxidation treatment were performed. An optimal plasticizer (glycerol) and a crosslinking agent (cinnamaldehyde) were added to the film-forming solution for film manufacturing, while physical treatment (high-pressure treatment, 276 MPa, 10 times) was done to improve physical properties. Then, the film was dried by a solution-casting method. Physical properties of food packaging materials such as tensile strength, elongation, water-solubility, thickness, and chromaticity were measured. In particular, the film to which 1.5% glycerol was added showed the highest value among the physical properties of the dried film. These results indicate that TEMPOSCG films have potential as eco-friendly food packaging materials in the food industry.