Effect of Ph on the Physicochemical Properties of a Cassava Peel Starch Biopolymer

Abstract

Background/aims: This study investigates how pH levels affect the characteristics of biopolymer films manufactured from cassava peel starch. Cassava peel starch's abundance and biodegradability make it a promising candidate for sustainable packaging. The study seeks to improve film qualities such as thickness, density, moisture content, solubility, and optical properties by altering pH levels. Understanding these effects is critical for increasing the acceptability of cassava peel starch biopolymers in a variety of industrial applications, notably environmentally friendly packaging solutions.

Methods: Starch extracted from cassava peel was used to produce films using the casting method at specified pH levels. The films were evaluated for thickness and density using classical methods. Moisture content was determined following the AOAC 930.15 (2000) protocol. Color analysis was conducted using the CIELab color space technique. Water solubility and solubility in acidic (HCl) and alkaline (NaOH) solutions were assessed through chemical solubility tests performed by gravimetry.

Results: The study investigated how pH impacts biopolymer films manufactured from cassava peel starch. The film thickness varied greatly across pH levels, with pH 10.5 creating the thickest films (0.158 ± 0.012 mm) and pH 6.5 providing the thinnest (0.118 ± 0.015 mm). Density varied slightly, from 1.393 ± 0.122 g/cc to 1.551 ± 0.153 g/cc. Moisture content fluctuated significantly, affecting biodegradability. Color study indicated pH-dependent variations in transparency and opacity, with higher pH values resulting in larger color deviations (∆E). Water solubility remained constant, but NaOH solubility dropped with increasing pH, peaking at pH 7.5 (23.44 ± 2.82%).

Conclusion: This work investigates the use of cassava peel starch for biopolymer synthesis at controlled pH levels. The findings demonstrate the material's practicality and provide critical insights for enhancing film qualities, particularly in a variety of industrial applications and environmentally friendly packaging solutions.

Keywords: Cassava peel starch biopolymer ; Food packaging ; Biodegradability.