The aim of this research was to characterize differences and sources of volatile flavor compounds by using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) and principal component analysis (PCA). Three sweet cherry fruits from different cultivars (cv. Tie, Van, and Lap) and their wines that were produced by the same yeast were detected. The results showed that 27 flavor compounds were identified in cherry fruits, including 10 alcohols, 7 esters, 7 aldehydes, 2 ketones, and 1 organic acid. Twenty-three flavor compounds were identified in cherry wines, including nine esters, eight alcohols, three aldehydes, two organic acids, and one ketone. In cherry fruits, aldehydes, several alcohols, and one ketone were the most prevalent in cv. Tie, and the majority of esters and alcohols in cv. Van. After fermentation, ethanol, butanol, butanal, ethyl propionate, propionaldehyde, 3-hydroxy-2-butanone, and acetic acid increased, whereas 1-hexanol, 3-methyl-3-buten-1-ol, 1-penten-3-ol, ethyl acetate, methyl acetate, (E)-2-hexenal and hexanal decreased. Few differences were detected in the type and content of volatile compounds in cherry wines from cv. Tieton (WT) and cv. Van (WV). Almost all aldehydes are derived from cherry fruits, which cannot be produced during wine-making, and other volatile compounds are almost all produced by saccharomyces cerevisiae. The volatile compounds of cherry wines were determined by row materials and fermentation cultures. Flavor fingerprints were established by HS-GC-IMS and PCA, which provided a theoretical foundation for the evaluation and improvement of flavor quality in cherry wine-making.

In order to make HPI have a wide application prospect in the food industry, we used EGCG to modify HPI. In this study, we prepared different concentrations (1, 2, 3, 4, and 5 mM) of (−)-epigallocatechin gallate (EGCG) covalently linked to HPI and use methods such as particle size analysis, circular dichroism (CD), and three-dimensional fluorescence spectroscopy to study the changes in the structure and functional properties of HPI after being covalently combined with EGCG. The particle size data indicated that the covalent HPI-EGCG complex was larger than native HPI, and the particle size was mainly distributed at about 200 μm. CD and three-dimensional fluorescence spectroscopy analyses showed that the conformation of the protein was changed by conjugation with EGCG. The β-sheet content decreased from 82.79% to 66.67% after EGCG bound to the protein, and the hydrophobic groups inside the protein were exposed, which increased the hydrophobicity of the protein and changed its conformation. After HPI and 1 mM of EGCG were covalently bonded, the solubility and emulsifying properties of the covalent complex were improved compared with native HPI. These results indicated that HPI-EGCG conjugates can be added in some foods.

Heat-soak and quick freezing could deteriorate the texture of vegetables. In this work, it was found that calcium chloride-sodium alginate (SA) could improve the appearance, brittleness, and chewiness of processed Heracleum moellendorffii (HM), a kind of popular nutritious wild vegetable in China. The effect resulted from the increase of calcium content in the vegetable, which was closely related to the ratio of calcium chloride to SA, the concentration of texture retaining agent, and soaking time significantly ( ). The best way to maintain the texture was to soak HM in 4 g/L of calcium chloride-SA (mass ratio 1 : 2) at 50°C for 30 minutes. The calcium content was increased to 71.56 mg/100g, and the brittleness and chewiness were 4630 gf and 2583.33 gf, respectively. The microstructure found that calcium could adhere to an inherent position on the cell membrane and protected the sample from cell damage and chloroplast spilling from the cell during thawing and quick freezing. The results showed that calcium chloride-SA treatment may be a promising method to improve the texture of vegetables during quick-frozen storage.

To address the issues of low extraction yield and insufficient retention of active components in the volatile oil of Northern Artemisia argyi leaves, and to clarify the commercial suitability of the process, this study investigated the effects of six pretreatment methods on the volatile oil of Artemisia argyi leaves grown in Liaoning for 75 days. The results showed that freeze-drying (-50°C, 200 Pa, 12 h), shade-drying (5°C ± 2°C, 50% ± 5% humidity, 7 d), and bio-enzyme pretreatment (cellulase 0.4%, pH 4, 50°C, 4 h) were optimal, with a volatile oil extraction yield of 1.87% to 1.91% (nearly double that of fresh Artemisia argyi leaves), caryophyllene content of 2.89% to 3.05%, and phytol content of 8.51% to 8.95%, exhibiting excellent properties. In contrast, micro-thermal explosion, steam explosion, and acid-base pretreatment resulted in loss of active components and low commercial cost-effectiveness. Commercially, freeze-dried products are suitable for pharmaceutical-grade raw materials (800-1200 RMB/kg), shade-dried products for food preservation-grade raw materials (300-500 RMB/kg), and bio-enzyme pretreated products for cosmetic-grade raw materials (600-800 RMB/kg). This study provides support for the industrialization and high-value applications of volatile oil from Northern Artemisia argyi leaves.