Bacterial nanocellulose production using cost-effective, environmentally friendly, acid whey based approach

Abstract

This study investigates the production of bacterial nanocellulose (BNC) film using a symbiotic culture of bacteria and yeasts (SCOBY) in acid whey medium. The yields were 59.58 g/L for wet and 2.75 g/L for freeze-dried BNC films in four days. The film contained cellulose nanofibrils with diameters ranging from 20 nm to 100 nm with a 34.3 % crystallinity index as confirmed by X-ray diffraction. Incorporating glycerol as a plasticizer modified the mechanical and thermal properties of the BNC film, reduced brittleness, and enhanced strain from 0.75 % to above 16 %. Fourier Transform Infrared Spectroscopy analysis identified intermolecular hydrogen bonding between the BNC film and glycerol. The glass transition temperature increased from roughly 158 °C to above 166 °C. The study validates the potential of acid whey as a viable alternative substrate for the production of BNC. The production method providing environmental benefits, cost-efficiency, and scalability, it also delivers an effective circular economy solution.