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Angelica keiskei is a kind of food–medicine plant with many biological effects, which has been used for the production of medicinal tea. In this study, the volatile compounds in Angelica keiskei tea were extracted and analyzed by headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC–MS). The aroma profiles of different tea samples were further distinguished by electronic nose (E-nose) combined with principal component analysis (PCA). Then the taste-active components and sensory attributes were also analyzed. A total of 118 aroma components were identified, among which myrcene, β-linalool, octanal, nonanal, (E)-2-nonenal, (Z)-2-nonenal, (E,E)-2,4-decadienal, (E,E)-2,4-nonadienal, (E)-2-decenal, and p-cymene were the key odorants, presenting floral, fruity, and fresh flavor. Sensory evaluation showed both leaf and stem teas had lower bitterness and astringency, higher aroma, umami, and sweet aftertaste than the root tea. Correlation analysis revealed the intensity of bitterness and astringency positively correlated with chalcone and free amino acid contents, while negatively correlating with soluble sugar content. The intensity of sweet aftertaste and umami had reverse correlation effect. Angelica keiskei leaf and stem teas are relatively fragrant, umami, and sweet with little bitterness and astringency taste. However, this study gives a thorough view of flavor characteristic of Angelica keiskei medicinal tea.

Microorganism species and inoculation fermentation methods have great influence on physicochemical and flavor properties of rice wine. Thus, this work investigated microbial interactions and physicochemical and aroma changes of rice wine through different inoculation strategies of Wickerhamomyces anomalus (W. anomalus) and Saccharomyces cerevisiae (S. cerevisiae). The results underlined that inoculation strategies and non‐Saccharomyces yeasts all affected the volatile acidity, total acidity, and alcohol content of rice wine. The sequential cofermentation consumed relatively more sugar and resulted in the higher ethanol content, causing reduced thiols and increased alcohols, esters, phenylethyls, and terpenes, which was more conducive to improve rice wine flavor than simultaneous cofermentation. Moreover, simultaneous cofermentation increased fatty aroma of rice wine, while sequential cofermentation increased mellow and cereal‐like flavor. These results confirmed that sequential cofermentation of S. cerevisiae and W. anomalus was a choice for the future production of rice wine with good flavor and quality.

Antifreeze peptides regulate the physiological functions of frozen cells and even their apoptosis; however, the mechanisms by which antifreeze peptides regulate these processes remain unclear, although the interactions between cell membranes and ice are well known to be important in this process.Our study aims to investigate how antifreeze peptides regulate cell physiological functions during the freezing process.We investigated the cryoprotective effect of rsfAFP on the physiological functions of S. thermophilus under freezing stress by measuring cellular metabolism activity, intracellular enzyme activity, cell membrane characterization, and cell apoptosis. The mechanism by which rsfAFP impacts S. thermophilus physiological functions under freezing stress was investigated using multispectral techniques and cryo-TEM.We show that a recombinant antifreeze peptide (rsfAFP) interacts with the extracellular capsular polysaccharides and peptidoglycan of Streptococcus thermophilus and ice to cover the outer layer of the membrane, forming a dense protective layer that regulates the molecular structure of extracellular ice crystals, which results in reduced extracellular membrane damage, depressed apoptosis and increased intracellular metabolic activity. This interaction mechanism was indicated by the fact that S. thermophilus better maintained its permeability barrier, membrane fluidity, membrane structural integrity, and cytoplasmic membrane potential during freezing stress with rsfAFP treatment.These results provide new insights into the mechanism by which rsfAFP regulates frozen cellphysiological functionsand apoptosis under freezing stress.

Microorganism species and inoculation fermentation methods have great influence on physicochemical and flavor properties of rice wine. Thus, this work investigated microbial interactions and physicochemical and aroma changes of rice wine through different inoculation strategies of Wickerhamomyces anomalus (W. anomalus) and Saccharomyces cerevisiae (S. cerevisiae). The results underlined that inoculation strategies and non‐Saccharomyces yeasts all affected the volatile acidity, total acidity, and alcohol content of rice wine. The sequential cofermentation consumed relatively more sugar and resulted in the higher ethanol content, causing reduced thiols and increased alcohols, esters, phenylethyls, and terpenes, which was more conducive to improve rice wine flavor than simultaneous cofermentation. Moreover, simultaneous cofermentation increased fatty aroma of rice wine, while sequential cofermentation increased mellow and cereal‐like flavor. These results confirmed that sequential cofermentation of S. cerevisiae and W. anomalus was a choice for the future production of rice wine with good flavor and quality., Rice wine of sequential cofermentation had mellow and cereal‐like aroma. Sequential cofermentation was more potential to improve rice wine flavor and quality.

The feasibility of near-infrared (NIR) spectroscopy for determining total dietary fiber (TDF) and mineral elements (mainly K, Mg, P, and S) in Coix seed was investigated. Partial least squares regression (PLSR) was applied to establish quantitative models. Norris derivative smoothing (NDS) was used as pretreatment method. A comparison of three variable selection methods, namely competitive adaptive reweighted sampling (CARS), genetic algorithms (GA), and random frog (RF), showed that CARS obtained the best performances of PLSR models with the effective wavelengths mainly concentrated on around 12,000–11,000 cm−1 and 6500–3600 cm−1. For the quantitative determination models of TDF, K, Mg, P, and S, the optimal root mean square error of prediction (RMSEP) values were 0.0923, 182.7224, 75.4987, 162.6993, and 36.6278; the r values were 0.95, 0.88, 0.80, 0.96, and 0.96; the residual predictive deviation (RPD) values were 2.68, 2.05, 1.70, 3.24, and 3.04, respectively. It is concluded that the NIR spectral technique has a potential to determine TDF, K, Mg, P, and S in Coix seed.

The feasibility of near-infrared (NIR) spectroscopy to determine fat, protein, and amino acids (AAs) in Coix seed was investigated. Partial least squares (PLS) regression was applied to establish quantitative model. Competitive adaptive reweighted sampling (CARS) and Norris derivative smoothing (NDS) were used to improve the model accuracy. For fat, protein, Asx, threonine, serine, Glx, alanine, leucine, proline, lysine, and histidine, NDS pretreatment improved the models’ performance and yielded better prediction results. Then, key variables were selected by CARS, and the PLS models could obtain the optimal results with good predictive ability and robustness. The models of protein, Asx, serine, Glx, alanine, valine, isoleucine, leucine, phenylalanine, and proline were fit for screening with the residual predictive deviation (RPD, the ratio between the standard deviation of the reference value and the root mean square error of prediction of the validation set) equal or greater than 2.50. The RPDs of fat and threonine were 1.61 and 2.00, and the other AAs’ were less than 1.50. It was concluded that the NIR spectral technique was suitable for determining fat, protein, and most of AAs in Coix seed. The technique might also give a rough estimate of the contents of glycine, cysteine, methionine, tyrosine, arginine, lysine, and histidine.

Isobavachalcone and 4-hydroxyderricin, two major chalcone constituents isolated from the roots of Angelica keiskei KOIDZUMI, exhibit numerous biological activities. Quantum chemical methods have been employed to investigate their structural and spectral properties. The ground state structures were optimized using density functional B3LYP method with 6-311G (d, p) basis set in both gas and solvent phases. Based on the optimized geometries, the harmonic vibrational frequency, the 1 H and 13 C nuclear magnetic resonance (NMR) chemical shift using the GIAO method were calculated at the same level of theory, with the aim of verifying the experimental values. Results reveal that B3LYP has been a good method to study their vibrational spectroscopic and NMR spectral properties of the two chalcones. The electronic absorption spectra were calculated using the time-dependent density functional theory (TDDFT) method. The solvent polarity effects were considered and calculated using the polarizable continuum model (PCM). Results also show that substitutions of different electron donating groups can alter the absorption properties and shift the spectra to a higher wavelength region.

Citral is one of the most important flavor compounds in fresh juice and lemon oil. Unfortunately, citral is chemically unstable and degrades over time in aqueous solutions. Here, citral nanoemulsions including a mixture of gelatin and Tween 20 as emulsifiers were produced in an effort to maintain the stability of citral in an acidic system.The mean droplet size and polydispersity index of the citral nanoemulsion were 467.83 nm and 0.259 respectively when the mass ratio of gelatin/Tween 20 was 3:1 and the total emulsifier concentration of the emulsion system was 10 g kgThe mixture of gelatin and Tween 20 enhanced the stability of citral under acidic conditions and could be used as an effective emulsifier to protect citral from degradation under acidic environments in the food industry. © 2016 Society of Chemical Industry.

The antioxidant capacities of the selected flavonoids quercetin, luteolin and taxifolin have been investigated at density functional level of theory with the aim of verifying the cellular antioxidant activity (CAA) values representative of experimental findings. The selected flavonoids were believed to act through the H-atom transfer mechanism. Their potentiality of hydrogen abstraction was evaluated by computing the O H bond dissociation enthalpy (BDE) in gas-phase and in dimethylsulfoxide solution. Results indicate that the order of antioxidant efficacies calculated in this work is in agreement with that reported by experimental results of CAA. Time-dependent density functional theory (TDDFT) calculations were also performed both in gas-phase and in dimethylsulfoxide to reproduce the electronic UV–vis spectra of the selected flavonoids.

In this study, the preparation and trophic characterization of perilla chewable tablet were investigated. Perilla chewable tablet was prepared according to the following process: mixing perilla raw materials with excipients, making wet granules, drying, tabletting and coating. The optimal formula was determined as follows: 8% perilla powder, 2.5% perilla extract powder, 20% isomaltooligosaccharide, 20% microcrystalline cellulose, 44.4% lactose, 0.5% essence of perilla, 0.1% sucralose, 2% erythritol, 2% vitamin C, 0.5% magnesium stearate. Results from nutrient analysis showed that perilla chewable tablet was rich in essential vitamins and mineral substances, which are good for human health.

This study aimed to isolate and characterise a novel sericin antifreeze peptide and investigate its ice-binding molecular mechanism. The thermal hysteresis activity of ice-binding sericin peptides (I-SP) was measured and their activity reached as high as 0.94 °C. A P4 fraction, with high hypothermia protective activity and inhibition activity of ice recrystallisation, was obtained from I-SP, and a purified sericin peptide, named SM-AFP, with the sequence of TTSPTNVSTT and a molecular weight of 1009.50 Da was then isolated from the P4 fraction. Treatment of Lactobacillus delbrueckii Subsp. bulgaricus LB340 LYO with 100 μg/ml synthetic SM-AFP led to 1.4-fold increased survival (p < 0.05). Finally, an SM-AFP/ice binding model was constructed and results of molecular dynamics simulation suggested that the binding of SM-AFP with ice and prevention of ice crystal growth could be attributed to hydrogen bond formation, hydrophobic interaction and non-bond interactions. Sericin peptides could be developed into beneficial cryoprotectants and used in frozen food processing.