Optimization of Cellulose Extraction Parameters and Production of Nanocellulose from Black Carrot Juice Wastes

Abstract

Agricultural wastes are abundant worldwide with increased production and consumption activities as a result of human population growth. Waste recycling processes, which are important to support sustainable production, remain popular due to the increasing amount of agricultural waste. In particular, there are various studies on the recovery of valuable components from waste. In this context, the recovery of cellulose and nanocellulose from waste, which has the potential to be used and applied in many sectors, especially in food, draws attention. Although black carrot juice waste, which is one of the important agricultural wastes, is frequently used in the production of natural colorants, it was used for the production of cellulose and nanocellulose in this study due to its high cellulose content. Response Surface Method-Central Composite Design was used to improve the alkaline extraction conditions of cellulose for the optimum yield and whiteness index by using process parameters of NaOH concentration (2–12%), process temperature (25–110 °C), and time (60–240 min). The optimum process parameters were determined as the NaOH concentration (7.06%), process temperature (44.83°C), and time (114.21 min) for alkaline extraction of cellulose from black carrot juice waste where the yield of cellulose was 22.90±2.48%, and whiteness index was 60.32±0.07%. Nanocellulose was produced from cellulose obtained from black carrot juice waste by acidic hydrolysis using 25% H2SO4. Nanocellulose yield and whiteness index were found as 15.76±0.16% and 58.77±0.26% respectively. The average diameter (61±2.89 nm) and length (281±18.50 nm) of the nanocellulose were determined by Atomic Force Microscopy (AFM). As a result of the Fourier Transform Infrared (FTIR) spectroscopy, it was determined that non-cellulosic components were removed.