In this study, liquid chromatography–mass spectrometry (LC-MS) was employed to conduct untargeted metabolomics analysis on black rice (BR), milled black rice (MBR), wet germinated black rice (WBR), and high-temperature and high-pressure-treated WBR (HTP-WBR). A total of 6988 positive ions and 7099 negative ions (multiple difference ≥1.2 or ≤0.8333, p < 0.05, and variable importance in projection ≥1) were isolated, and 98 and 100 differential metabolic pathways were identified between the different samples in the positive and negative ion modes, respectively. Distinctive variations in the metabolic compositions of BR, MBR, WBR, and HTP-WBR were observed. Flavonoids, fatty acids, lipids, phenylpropanoids, polyketides, benzenoids, and organooxygen were the dominant differential metabolites. Milling removed the majority of bran-associated bioactive components such as phenolic acids, anthocyanins, micronutrients, fatty acids, antioxidants, and dietary fiber. The germination process significantly reduced the number of flavonoids, polyketides, and lipid-related metabolites, while enzymatic activation notably increased the number of organic acids and amino acids. HTP treatment synergistically enhanced the content of heat-stable flavonoids and polyketides, while simultaneously promoting fatty acid β-oxidation. These findings establish novel theoretical foundations for optimizing processing methodologies and advancing functional characterization in black rice product development.

Benzo[a]pyrene (BaP), a potent carcinogenic polycyclic aromatic hydrocarbon, is a critical food contaminant originating from environmental deposition and thermal processing, posing a significant threat to public health and driving stringent global regulations. This review critically examines recent advancements in analytical methodologies for BaP determination, giving particular emphasis to sample preparation and detection techniques. The discussion covers the evolution from conventional methods, such as solid-phase extraction, towards more efficient and sustainable approaches, including magnetic, dispersive, and molecularly imprinted solid-phase extraction, as well as microextraction techniques and gel permeation chromatography. For detection, the performance of established chromatographic methods, such as gas chromatography–mass spectrometry (GC-MS) and high-performance liquid chromatography with fluorescence detection (HPLC-FLD), is evaluated against emerging rapid techniques such as sensors, immunoassays, and spectroscopic methods. The analysis reveals that while significant progress has been made in improving sensitivity, selectivity, and throughput, challenges remain in balancing speed with accuracy, managing matrix effects, and translating novel materials from research to routine application. The review concludes by underscoring the necessity for future development to focus on the integration of smart materials, automation, and advanced data science to achieve robust, on-site, and holistic monitoring solutions for ensuring food safety against BaP contamination.

Growing demand for plant-based nutraceuticals drives the need for innovative bioprocessing strategies. This study developed an integrated approach combining germination and Lactobacillus-mediated fermentation to produce a γ-aminobutyric acid (GABA)-enriched functional beverage from brown rice. Systematic screening identified an optimal rice cultivar for germination. Sequential enzymatic liquefaction and saccharification were optimized to generate a suitable hydrolysate. Screening of 13 probiotic strains revealed that a 10-strain Lactobacillus–Bifidobacterium consortium maximized GABA synthesis (12.2 mg/100 g). Fermentation parameters were optimized to 0.25% monosodium glutamate, 4% inoculum, 10 μmol/L pyridoxine hydrochloride, 37 °C, and 24 h. The resulting beverage achieved significantly elevated GABA concentrations while exhibiting low fat (0.2 g/100 g), reduced caloric content (233.6 kJ/100 g), and high viable probiotic counts (2 × 10⁸ CFU/g). This strategy demonstrates significant potential for the scalable production of multifunctional, plant-based nutraceuticals with targeted bioactive components.

Metabolic diseases such as high blood lipids, high blood sugar, and disrupted gut microbiota pose a serious threat to people’s physical health. The occurrence of these diseases is closely related to the lack of nutrients in daily rice staple foods, but there is a lack of comprehensive analysis of the underlying mechanisms. This study used fully nutritious brown rice as raw material, and after germination under various stress conditions, it significantly increased the levels of gamma aminobutyric acid (GABA, four carbon non protein amino acid), resistant starch, flavonoids, and other components that regulate metabolic diseases. Using rats as experimental subjects, a model of hyperlipidemia and hyperglycemia was constructed, with rice consumption as the control. The experimental period was 8 weeks. Research has found that feeding sprouted brown rice can significantly improve the accumulation of white fat in the liver caused by a high-fat diet, significantly reduce TC, TG, LDL-C, apoB, HL, LPL, and LCAT, significantly increase HDL-C and apoA1, and significantly reduce the levels of inflammatory factors IL-6 and TNF-α. Therefore, consuming sprouted brown rice can reduce the risk of hyperlipidemia, inflammation, and tumor occurrence by promoting fat breakdown, and can also increase the abundance of metabolic-promoting microorganisms (especially Euryarchaeota and Lactobacillus) in the intestine, improving the entire metabolic ecological network of rats.

This study investigated the combined effects of lactic acid bacteria (LAB) fermentation and different milling methods (wet, semi-dry, and dry) on the physicochemical properties of glutinous rice flour (GRF) and the texture of the final product. A systematic analysis of rice samples treated with three LAB strains (Lactiplantibacillus plantarum CGMCC 1.12974, Limosilactobacillus fermentum CICC 22704, and Lactobacillus acidophilus CICC 22162) revealed that fermentation pretreatment created favorable conditions for subsequent physical milling by degrading the protein network and modifying the starch structure. The results demonstrated that fermentation combined with dry or semi-dry milling significantly improved the whiteness of GRF and the contents of γ-aminobutyric acid (GABA), total phenols, and total flavonoids, while reducing the contents of damaged starch (except in samples fermented with Lb. acidophilus) and protein by 2.91–12.43% and 17.80–32.09%, respectively. The functional properties of the GRF were also optimized: fermented flour exhibited higher peak viscosity, lower gelatinization temperature, and higher gelatinization enthalpy. Texture profile analysis revealed that glutinous dumplings prepared from fermented dry/semi-dry milled GRF, particularly those fermented with Lp. plantarum, showed significantly reduced hardness and chewiness, along with significantly improved cohesiveness and resilience. Consequently, their texture approximated that of high-standard wet-milled products. Correlation analysis based on the top ten discriminative features selected by random forest identified peak viscosity and breakdown viscosity as the most important positive factors associated with superior texture (high resilience, high cohesiveness, and low hardness), whereas damaged starch content and protein content were key negative correlates. In summary, this study confirms that the combination of fermentation and milling exerts a beneficial influence on the functional quality of GRF.

Brown rice is a nutritious, gluten-free whole grain, the edible potential of which is limited by inferior palatability and storage stability. In this study, brown rice (20% w/w) was subjected to heat moisture treatment (HMT) at 110 °C for 2 h, followed by ultrafine grinding, to prepare gluten-free biscuits, which were compared with those made from wheat flour, white rice, and brown rice. The results showed that the content of dietary fiber (2.67–3.62%), total phenolic (0.053–0.154%), and vitamin E (0.574–1.483 mg/100 g) in brown rice biscuits after combined treatment was enhanced compared with wheat flour biscuits. The spread ratio (4.06–8.89), hardness (700.82–1085.91 g), and brittleness (1068.89–2067.18 g/sec) of the biscuits were significantly improved (p < 0.05). Scanning electron microscopy revealed that the biscuits treated with combined treatment had fewer cavities and a more compact texture. The biscuits made from HMT brown rice demonstrated a reduced peroxide value, with a slower increase in acid value (0.19–0.21 mg/g) compared to untreated samples (0.24–0.38 mg/g) during storage. The innovative combined treatment of HMT and ultrafine grinding improved qualities of brown rice biscuits. This approach expands the utilization potential of brown rice, while also offering a viable strategy for grain conservation and loss reduction.