High-intensity, Low-frequency Ultrasound Treatment as Sustainable Strategy to Develop Innovative Biomaterials from Agri-food Byproducts and Wastes

Bioconversion is an important avenue for finding value from biomass waste produced by the agricultural industry. One avenue of conversion is the development of upcycling byproducts and waste from food processing to value-added products. This includes degradable biomaterials which have real potential to reduce waste, improving economic, social and environmental impacts. As such, this research paper was focused on exploring two avenues of bioconversion from waste products of tomato skin, hemp meal and hops vines- identification of phytochemicals and the development of bioplastic. Combined to these researches, the effect of Ultrasound as a green technology was studied in both contexts. It was found that Ultrasound treatment reduced extraction time for saponin and phenolic acid from tomato skin, hemp meal and/or hops vines from 24h to 30 min. However, Ultrasound Assisted Extraction (UAE) was shown to affect the phenolic acid and saponin profiles of certain extracts. Ultrasound treatment was shown to positively impact the overall microscopic structure and qualities of bioplastic such as water activity, percentage moisture, hardness, cohesiveness, resilience, and springiness index. This study suggests that Ultrasound can be used as sustainable non-thermal method for extraction of active saponins and phenolics but also in bioplastic formulation to enhance physico-chemical characteristic.