Fabrication of brewer's spent grain fortified bio-based edible bowls: a promising alternative to plastic containers

Plastic waste cannot be easily recycled or decomposed since it is not an organic substance. Due to the uncontrolled manufacturing of plastic items, a significant amount of plastic waste has been generated. There is a growing need for a sustainable alternative to the synthetic petrochemical-made plastic-based materials. Nowadays, plastic-based cake mold is a very common daily used product. Therefore, biobased bowls could be a suitable substitute for plastic counterparts. In this work, a biobased edible bowl/cake mold was fabricated using natural ingredients such as finger millet, refined flour, jaggery, and xanthan gum. The developed cake mold was further fortified with the addition of varying content (0-10%) of brewer's spent grain (BSG). The BSG-added cake mold (S4) showed similar to fivefold low water absorption and also similar to threefold reduction in oil absorption proficiency with respect to control. Moreover, the fortified cake mold itself exhibited excellent antioxidant activity, and interestingly, the antioxidant action was further improved (similar to 25% increment in S4) by the addition of BSG. The hardness of the edible bowl was significantly increased (similar to threefold) in the presence of the S4 sample. Also, the developed cake mold/bowl was biodegradable, as observed from the preliminary soil degradation test. Hence, the outcome of the present work could be a promising approach for producing a safer alternative to plastic-based cake mold/bowl.