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In this study, an acetic acid-ethanol model spirit with 40% alcohol, 1000 ppm was treated using high-pressure homogenization (HPH) (1, 3 and 5 cycles; 30, 50, 70 MPa) to investigate the synthesis effectiveness of ethyl acetate. The result showed that ethyl acetate increased 342% after a 5 cycle treatment. In the HPH treatment (30–90 MPa under 10–25 °C with 1–7 cycles) of commercial sorghum spirit, the test shows that ethyl acetate and ethyl lactate were 2316 and 1586 ppm, respectively, while no obvious changes were observed in methanol, fusel oil and total acidity, and only a slight decline in ethanol. In addition, the results also show that HPH treatment can reduce the methanol content and produce other aroma compounds such as methyl acetate. Sensory evaluation also revealed improvement effects on flavor, smoothness, aftertaste and acceptability of the artificial aging technology on the production of spirits.

Microorganisms produce hundreds of aroma-active compounds during fermentation process which affect the flavor of the final wine product. The current study explored the enological characteristics of non-Saccharomyces yeast strains and their influence on aroma compound complexity during fermentation process. Forty-two yeast strains were isolated from fruits by the DNA sequencing identification. Hanseniaspora uvarum Pi235, Pichia kluyveri Pe114, Saccharomyces cerevisiae Gr112 and Hanseniaspora guilliermondii Ki135 were selected for the following experiments due to the safety considerations and aroma diversity. Biochemical characteristics results showed that H. uvarum Pi235, P. kluyveri Pe114 and S. cerevisiae Gr112 exhibited different consumption preference in maltose, xylose and glycerol assimilation compared with their standard strains. Enological characteristics results showed that S. cerevisiae Gr112 exhibited best thermal tolerance, ethanol tolerance and β-glucosidase activity. Results of volatile aroma compounds analysis showed that non-Saccharomyces yeast strains were good at producing esters, such as ethyl acetate and 2-phenethyl acetate which were 11.8–25.4 and 4.1–15.2 folds higher than that from S. cerevisiae Gr112. Non-Saccharomyces yeast strains would provide more divers flavors in wines. The results will increase the applicability of non-Saccharomyces yeasts in the winemaking industry.

Multiple hard-to-reach spots on foods with rough surfaces (such as shrimp) limit the maximal exposure to antibacterial agents. In this study, we successfully generated plasma-activated water (PAW) using a low energy-consuming source of a non-thermal atmospheric piezoelectric direct discharge plasma (PDDP) system and evaluated its effectiveness as a glazing agent on shrimp, facilitating a whole surface treatment. During generation, a feeding gas mixture of N2 (80%): O2 (20%) and N2 (85%): O2 (15%) was revealed to optimally produce reactive oxygen species (ROS) such as H2O2 (60.7 ± 0.2 mg/L) and O3 (0.45 ± 0.02 mg/L) as well as reactive nitrogen species (RNS) such as NO2‾ (48.5 ± 0.5 mg/L). Furthermore, the application of PAW-glazing on shrimps was demonstrated to be capable of maintaining microbial growth below 6 log CFU/g throughout the storage period (9 days). This approach also possessed the capacity to retard the loss of both physical (color and firmness) and chemical characteristics (pH, total volatile basic nitrogen [TVBN], and thiobarbituric acid reactive substance [TBARS]) of PAW-glazed shrimps. Finally, this study demonstrated the effectiveness of glazing with PAW generated from the PDDP system as a potential prevention agent for shrimps.

This study investigated the effects of HVEF as a potential postharvest technology in persimmon cultivation ( Diospyros kaki ). We used an electric field strength of 600 kV/m and treated samples for different lengths of time (0, 30, 60, 90 or 120 min) before storing the fruit for 15 d. The results showed that HVEF can reduce the rate of weight loss by 1.0–3.4-fold, demonstrating not only that HVEF has the ability to delay tissue deterioration but that the effect increases with treatment time. HVEF also delays the rate of decreasing hardness by 1.0–1.3-fold, indicating that it may have the ability to inhibit the activity of tissue enzymes. HVEF further demonstrated the ability to suppress the rate of malondialdehyde (MDA) production by 1.46–11.22-fold; increasing the treatment time improved the efficacy of the inhibition. HVEF can also delay the decreasing rate of carbon dioxides yield by 1.0–2.3-fold, indicating that it has the ability to inhibit metabolism. This inhibition rate of carbon dioxides yield also results in a delay of organizational deterioration. Finally, HVEF inhibited pectinesterase activity and had no impact on the amount of total phenols.

Oyster mushrooms (Pleurotus ostreatus, P. ostreatus) are rich in nutrients and have a pleasant flavour. However, they brown easily during storage, reducing consumer acceptance and decreasing market value. The present study was aimed at assessing the inhibitory effect of an alternating current electric field (ACEF) on the browning of oyster mushrooms and the possible mechanisms involved. Results revealed that treatment of P. ostreatus mushrooms with an ACEF (600 kV/m, 50 Hz, 120 min) reduced the browning of oyster mushrooms by 40% after 12 d of storage, and the effect was closely related to the inactivation of polyphenol oxidase, the delay of electrolyte leakage, and lower malondialdehyde levels that may be a consequence of decreased lipoxygenase activity. In conclusion, ACEF treatment can increase the quality of P. ostreatus during storage by delaying browning.

This study investigated the effect of ultrasonic and freezing pretreatment on S-ally cysteine (SAC) content in garlic during heat-processing at 40 °C for 15 days and also compared the browning degree and cell structure of ultrasonic and freezing pretreatment in garlic. Processing different times at the same frequency showed that ultrasonic pretreatment at 28 kHz for 3 h (2.51 ± 0.22 mg/g dry weight) is significantly higher than that for 1 h (1.83 ± 0.29 mg/g) after being heated at 40 °C for 6 days. The results of ultrasonic pretreatment for processing different frequencies at the same time finds that a frequency of 28 kHz for 2 h (3.15 ± 0.19 mg/g dry weight) has a better effect at increasing the SAC content in garlic than does 56 kHz for 2 h (2.69 ± 0.22 mg/g dry weight) after being heated at 40 °C for 15 days. A comparison of both pretreatments shows that the SAC content in garlic undergoing freezing pretreatment is significantly higher than that for ultrasonic pretreatment. Hence, ultrasonic pretreatment has a shorter processing time but needs more applications in the food industry to enhance the SAC content in garlic; however, it also maintains garlic's whole appearance and original color.

This research is mainly focused on preparing gallic acid (GA) coated, antimicrobial, active packaging, low density polyethylene (LDPE) films by capacitively coupled plasma. Firstly, the suitable plasma treatment condition was 30 W treated for 60 s from the result of appearance and tensile strength. From the result of SEM and ATR-FTIR, the surface roughness increased which facilitated the GA coating and the surface turn smoother after GA coating. In the result of antimicrobial activity, these films is able to reduce the growth of Gram-negative bacterium Escherichia coli and Gram-positive bacterium Staphylococcus aureus about 0.5–0.6 log CFU/mL when GA concentration is above 1%. Between these two microorganisms, the film has more significant inhibition on E. coli than S. aureus due to cell membrane structure differences. These results are first stage in developing antibacterial active packaging for foods preservation.

5-hydroxymethylfurfural (5-HMF) is regarded as a neo-formed contaminant (NFC) that may negatively affect human health. Among the foods undergoing thermal processing, the 5-HMF content of black garlic is relatively high. However, many researches have shown that 5-HMF has antioxidant ability; therefore, in this study, we aimed to explore the use of epigallocatechin gallate (EGCG) to reduce 5-HMF whether would also affect the antioxidant ability of black garlic. Hence, mitigating the 5-HMF formation in black garlic and increasing the safety of black garlic consumption were the purposes in this study. At the 30th day of aging, the 5-HMF content of garlic with EGCG impregnation for 12 h was 2.37 ± 0.11 mg/g dry weight, which mitigated the formation of 5-HMF by approximately 50% compared with the control. It indicated that EGCG could be adducted with 5-HMF to reduce the formation of 5-HMF during the production of black garlic. Moreover, it also found that as the impregnation time increased, the antioxidant ability of black garlic was higher. EGCG impregnation is a useful method for mitigating 5-HMF formation in black garlic without affecting the bioactivity of black garlic, such as its antioxidant ability.