Qingli Xie

The high-temperature crystalline transformation of spodumene is critical for efficient lithium extraction and utilization. In this study, we employ Raman spectroscopy to investigate the phase transition behavior of spodumene under thermal treatment. The results reveal that the optimal transformation conditions for Nigerian spodumene are achieved at 1050 °C with a 30 min dwell time, as validated by X-ray diffraction (XRD). Comparative analysis demonstrates that Raman spectroscopy offers distinct advantages over XRD, including minimal sample preparation and the ability to conduct ex situ measurements of spectral changes after heat-induced phase evolution. These findings highlight the potential of Raman spectroscopy to guide process optimization in lithium extraction by precisely identifying crystallographic transformation thresholds.

Hemp seed protein hydrolysate (HSPH), despite its high digestibility and solubility, exhibits severely impaired gelation properties due to extensive hydrolysis, thereby limiting its food applications. This study analyzed the effect of homogeneously incorporating commercial hemp seed protein concentrate (HSPC) into HSPH on physicochemical and structural properties of the resultant composite gels. As the HSPC concentration increased from 100 to 150 mg/mL, the composite gels exhibited a significant enhancement in hardness (p < 0.05), increasing from 1.63 to 5.74 N, along with an improvement in water-holding capacity (WHC) from 45.52 to 55.46 g/g. Concurrently, the storage modulus (G′) and gelation temperature increased, with the latter rising from 65 to 78 °C. SDS-PAGE analysis suggested that the enhanced composite gel properties were attributed to its high-molecular-weight protein fractions (10–15 kDa and 40–50 kDa) of HSPC, which functioned as the primary structural components of the gel network. In addition, the formation of denser yet irregular microstructures was observed by scanning electron microscopy (SEM) analysis when HSPC incorporation increased from 0 to 200 mg/mL. Fourier-transform infrared (FTIR) further suggested that these improvements were due to increases in β-turn and random coil contents by approximately 9.60 and 7.73%, respectively. These findings provided insights into the utilization of HSPH and HSPC in plant-based foods and contributed to food security and sustainable agriculture.

Camellia oil, rich in monounsaturated fatty acids, squalene, tocopherols, and polyphenols, is highly valued for its nutritional benefits. However, its high market value and regional variations have led to frequent adulteration, highlighting the need for rapid, non-destructive methods for authentication, geographical traceability, and quality assessment. This study employed portable Raman spectroscopy combined with Partial Least Squares Discriminant Analysis (PLS-DA) and Multivariate Curve Resolution–Alternating Least Squares (MCR-ALS) to differentiate camellia oil from other edible oils and evaluate its thermal and photo-oxidative stability. PLS-DA, based on VIP-selected spectral variables, effectively distinguished camellia oil, with Raman bands near 1250 cm⁻¹ and 1650 cm⁻¹ contributing significantly. A unique peak at 1525 cm⁻¹, observed in samples from Gongcheng, Guangxi, was associated with carotenoids and served as a potential marker for geographical traceability. MCR-ALS modeling revealed significant reductions in the 1650 cm⁻¹ and 1525 cm⁻¹ peaks when temperatures exceeded 150 °C, indicating degradation of unsaturated fatty acids and carotenoids. Under UV exposure, the 1525 cm⁻¹ peak declined sharply and nearly disappeared after 24 h, suggesting rapid carotenoid degradation via photooxidation. Extended UV treatment also affected the 1650 cm⁻¹ peak and led to oxidative product accumulation. Overall, this study demonstrates the feasibility of integrating Raman spectroscopy with chemometric analysis for efficient oil classification, traceability, and stability monitoring, offering a valuable tool for food quality control and market supervision.