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.

Physalis pubescens L. is a seasonal fruit with high nutritional value but a short shelf life that limits its processing and utilization. This study integrated metagenomics and metabolomics to investigate the comparative effects of Lactiplantibacillus plantarum fermentation on volatile flavor metabolites and microbial community composition of P. pubescens by comparing initial (0 h) and post-fermentation (24 h) states. After 24 h of fermentation, 1316 volatile compounds were putatively identified by GC-MS, with 592 metabolites significantly changed and 501 upregulated and 91 downregulated. Key flavor compounds that impart citrus, floral, fruity, and rose notes including D-limonene, geraniol, D-carvone, and phenylethyl alcohol were markedly increased. Metagenomic analysis revealed that L. plantarum rapidly dominated the microbial community (relative abundance surged from <0.05% to ~72%) while effectively suppressing potential spoilage bacteria such as Escherichia coli. Functional gene annotation demonstrated significant enrichment of amino acid, carbohydrate, and fatty acid metabolism pathways, with key enzyme genes (L-lactate dehydrogenase, pyruvate oxidase, acetyl-CoA carboxylase) predominantly assigned to L. plantarum, suggesting their potential contribution to the generation of organic acids, ethanol, and esters. Spearman correlation analysis indicated that Lactobacillaceae genera were significantly positively correlated with terpenoids, phenols, alcohols, and aldehydes. This study provides the first metagenomics-metabolomics insight into the microbial and molecular mechanisms associated with flavor formation in LAB-fermented P. pubescens, offering a theoretical foundation for developing stable and controllable fermented fruit products.