The development of biodegradable and recyclable food packaging materials derived from biomass is a promising solution to mitigate resource depletion and minimize ecological contamination. In this study, lignin nanoparticles (LNPs) were effectively produced from bamboo powder using an eco-friendly recyclable acid hydrotrope (RAH) strategy. A sustainable CA/LNPs nanocomposite film was then designed by incorporating these LNPs into a casein (CA) matrix. The LNPs served as nucleation templates, inducing ordered hydrogen bonding and close packing of the CA chains. The addition of 5 wt% LNPs significantly enhanced the mechanical properties of the film, with tensile strength enhanced to 21.42 MPa (219.7 % improvement) and elastic modulus rising to 354.88 MPa (220.3 % enhancement) compared to pure CA film. Notably, the resultant CA/LNPs nanocomposite film exhibited recyclable recasting characteristics, maintaining a reasonable mechanical strength even after three recasting cycles. The incorporation of LNPs also decreased the water solubility of the pure CA film from 31.65 % to 24.81 % indicating some interactions are taking place, while endowing the film with superior UV-blocking ability, achieving nearly complete absorption in the 200-400 nm range. Moreover, the inherent properties of LNPs imparted improved antibacterial and antioxidant activities to the CA/LNPs nanocomposite film. Owing to its comprehensive properties, the CA/LNPs nanocomposite film effectively extended the storage life of strawberries. A soil burial degradation test confirmed over 100 % mass loss within 45 days, highlighting excellent degradability of the films. Therefore, the simple extraction of LNPs and the easily recovery of p-TsOH provide significant promise and feasibility for extending the developed methodologies in this work to rapidly promote the produced films in fields such as degradable and packaging materials.

Utilizing casein in geotechnical engineering and construction can reduce global dairy waste. Variations in initial water content during sample preparation influence cation and OH ion availability, alkaline additive concentrations, casein binder function, and rheological properties of the casein solution. This study investigates the impact of initial water content and casein solution rheology on unconfined compressive strength in two soil types (coarse and fine) treated with casein, both in dry conditions and after water immersion. The study also assesses the long-term performance of casein-treated soil under bio-decomposition. Results suggest that increasing casein content, beyond the optimal ratio, can enhance strength by adjusting initial water concentration. Notably, calcium caseinate-treated soil shows improved water resistance, with wet strength reaching 833 kPa at 5% casein and 20% initial water content, due to reduced viscosity and better workability, resulting in a more rigid soil structure during preparation. We propose an empirical formula describing the influence of casein solution rheological characteristics on soil strength. Furthermore, artificial neural networks, developed from experimental data, predict casein-treated soil strength, highlighting the significance of initial water content and rheological parameters.

This study explores the mechanical properties of casein-treated and agar-treated sand, considering biopolymer content, dehydration time, immersion periods, relative densities, porosity ratios, and porosity/volumetric biopolymer contents. Adding casein was found to improve the water resistance of agar-treated sand. Results reveal that 4 % and 5 % casein-treated sand exhibit the highest water resistance after a week of submersion, with wet strength of 0.359 MPa and 0.493 MPa, respectively. Increased relative density and biopolymer content correlate with higher unconfined compressive strength, inversely linked to sample porosity. An empirical equation connecting unconfined compressive strength to porosity/volumetric biopolymer content is derived.

The advent of biopolymers in the ground improvement industry has made significant contributions by reducing the carbon footprint and tremendous improvement in soil engineering properties at par with chemical stabilizers. The current study investigates the effect of two biopolymers, chitosan, and casein on the unconfined compressive strength (UCS) behavior of high-plasticity clay at varying dosages of 0.5%, 1%, 2%, and 4%. The study also evaluates the effect of curing periods up to 90 days on the untreated and biopolymer-treated clay. Chitosan and casein bring a 1428% increase and a 989% increase in UCS at the highest dosage of 4% and the highest curing period of 90 days. The nonlinear multivariate regression models establish a link between the experimental and best-fit data with the coefficient of multiple determination (R-2) > 0.98. Additionally, the reliability analysis assesses the efficacy of biopolymer-treated soils as an alternate embankment material. With an increase in curing period of up to 28 days, the chitosan-treated samples exhibit higher factors of safety compared to casein-treated samples. The modified embankment attains a target reliability index of more than 3.0 with minimum Chitosan content (Dch) of 2.25% and Casein content (D-ca) of 1.85% at Coefficient of Variation (COV) of UCSmin= 10% for 28-day cured samples. Thus, the reliability analysis presents a rational approach for using biopolymer-treated soils in embankment construction by considering the effect of dosage, curing period, and the variability associated with the UCS.

Lotus, an underutilised aquatic plant with strong fibres, shows potential as a raw material for biodegradable packaging. Against this backdrop, this study aimed to develop a biodegradable packaging material by harnessing Lotus fibre in conjunction with banana stems, pineapple leaves, and rice straw as reinforcing agents. Additionally, the influence of a tapioca starch binder was examined for comparative purposes. To further enhance the material's properties, a casein bio coating was applied. Analytical tests for mechanical properties, water barrier properties, functional groups, structure and microstructure, thermal properties and biodegradability were performed. The samples containing banana fibres (LB) showed the highest tensile strength (12.81 MPa) and bursting strength (7.09 KPa). The casein bio-coating enhanced all the mechanical properties while significantly improving the water resistance. The bio-coated samples showed contact angles within the range of 72.3-92.3 degrees, with the samples containing pineapple leaf fibres showing the maximum. Infrared spectra analysis confirmed robust interactions among the reinforcing agents while scanning micrographs confirmed the influence of the bio-coating. The thermogravimetric analysis revealed the coating to be slightly improving the thermal stability. The notable crystallinity index of LB samples substantiated their remarkable mechanical properties. A great deal of biodegradation was seen in 20 days of soil burial, which was expedited by the coating. The material was also able to be formed into carry bags without difficulty, thereby indicating the suitability of this material as a viable eco-friendly solution to plastic carry bags.