Sustainable thermoplastic carbohydrate-based polymeric materials, and sustainable plastic materials including an organic odor-reducing agent to counteract a slight burned carbohydrate odor resulting from inclusion of a carbohydrate-based polymeric material within the described materials. Such carbohydrate-based polymeric material may be starch-based, and the slight characteristic odor lent by such material may be that of a somewhat burned starch, such as a popcorn or caramel corn type odor. Applicant has found that this slight odor can be substantially removed by addition of a very small fraction of particular organic materials. 4-hydroxy-3-methoxybenzaldehyde (vanillin) has been found to be particularly effective, even in very small concentrations. Other freeze-dried fruit extracts (e.g., strawberry, raspberry, blueberry, etc.) may similarly be used. As little as 20 ppm of the organic odor-reducing agent is sufficient to substantially remove the characteristic burned starch odor. A ratio of the odor-reducing agent to the carbohydrate-based polymer may be less than 1:1000.