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The traditional Chinese Baijiu brewing process utilizes natural inoculation and open fermentation. The microbial composition and abundance in the microecology of Baijiu brewing often exhibit unstable characteristics, which directly results in fluctuations in Baijiu quality. The microbiota plays a crucial role in determining the quality of Baijiu. Analyzing the driving effect of technology and raw materials on microorganisms. Elucidating the source of core microorganisms and interactions between microorganisms, and finally utilizing single or multiple microorganisms to regulate and intensify the Baijiu fermentation process is an important way to achieve high efficiency and stability in the production of Baijiu. This paper provides a systematic review of the composition and sources of microbiota at different brewing stages. It also analyzes the relationship between raw materials, brewing processes, and brewing microbiota, as well as the steps involved in the implementation of brewing microbiota regulation strategies. In addition, this paper considers the feasibility of using Baijiu flavor as a guide for Baijiu brewing regulation by synthesizing the microbiota, and the challenges involved. This paper is a guide for flavor regulation and quality assurance of Baijiu and also suggests new research directions for regulatory strategies for other fermented foods. [ABSTRACT FROM AUTHOR]

BACKGROUND: There are few reports on the breeding of high‐yielding tetramethylpyrazine (TTMP) strains in strong‐flavor Daqu. In addition, studies on the mechanism of TTMP production in strains are mostly based on common physiological and biochemical indicators, and there is no report on RNA level. Therefore, in this study, a strain with high production of TTMP was screened out from strong‐flavor liquor, and transcriptome sequencing analysis was performed to analyze its key metabolic pathways and key genes, and to infer the mechanism of TTMP production in the strain. RESULTS: In this study, a strain with a high yield of tetramethylpyrazine (TTMP) was screened out, and the yield was 29.83 μg mL−1. The identified strain was Bacillus velezensis, which could increase the content of TTMP in liquor by about 88%. After transcriptome sequencing, a total of 1851 differentially expressed genes were screened, including 1055 up‐regulated genes and 796 down‐regulated genes. Three pathways related to the production of TTMP were identified by gene ontology (GO) annotation and COG annotation, including carbohydrate metabolism, cell movement and amino acid metabolism. The key genes of TTMP were analyzed, and the factors that might regulate the production of TTMP, such as the transfer of uracil phosphate ribose and glycosyltransferase, were obtained. CONCLUSIONS: A strain of B. velezensis with high TTMP production was screened and identified in strong‐flavor Daqu for the first time. The yield of TTMP was 29.83 μg mL−1, which increased the TTMP content in liquor by 88%. The key metabolic pathways of TTMP production in the strain were obtained: carbohydrate metabolism, cell movement and amino acid metabolism, and the key regulatory genes of each pathway were found, which complemented the gap in gene level in the production regulation of the strain, and provided a theoretical basis for the subsequent study of TTMP in liquor. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

To study the difference between the fungal community compositional and fragrance components in medium- and high-Temperature Taorong-type Baijiu Daqu. The microbial communities and fragrance components of Taorong-type Baijiu Daqu were analyzed using high-throughput sequencing (HTS) and headspace-solid-phase microextraction-gas chromatography-mass spectrometry (HS–SPME–GC–MS). With an abundance at the phylum and genus levels ≥0.01% as the threshold, 3 phyla, Mucoromycota, Ascomycota, and Basidiomycota, were found in both medium- and high-temperature Daqu, but their abundances differed. At the genus level, 15 and 13 genera were recognized. Rhizopus (72.40%) and Thermomyces (53.32%) accounted for the most significant proportions in medium-temperature and high-temperature Daqu, respectively. Medium-temperature Daqu and high-temperature Daqu were found to have 40 and 29 fragrance components, respectively and contained the highest proportions of pyrazines (53.12%) and acids (32.68%). Correlation analyses between microbes and fragrance components showed that Aspergillus, Hyphopichia, Trichosporon, Alternaria were all highly and positively correlated with pyrazines, but the dominant fungal communities were highly correlated with only a few individual acid compounds but not with acid compounds overall. The unique Daqu -making process and environment lead to these differences. [ABSTRACT FROM AUTHOR]

Pomegranate is a kind of fruit with low temperature sensitivity. Abnormal low temperature can easily lead to chilling injury, which negatively impacts the appearance of fruit, accelerates browning and deterioration, as well as seriously reduces the consumption quality and commodity value of pomegranate. This study was carried out to determine the effect of methyl jasmonate on chilling injury of pomegranate during low temperature storage. The result showed that methyl jasmonate treatment effectively maintained edible quality of pomegranate, suppressed the polyphenol oxidase activity and the development of chilling injury index, and inhibited the decline of total phenol content and the increase of malondialdehyde content and cell membrane permeability. In addition, methyl jasmonate could also enhance the disease resistance of fruit by increasing the content of soluble protein, and effectively maintain the integrity of epidermal cell structure and tissue structure. Overall, the conclusion of this paper is that methyl jasmonate can be used as an effective means to suppress chilling injury in postharvest storage of pomegranate. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of storage temperature fluctuation (TF) (15 ± 5°C, 15 ± 1°C, and 15 ± 0°C) on the ripening quality and antioxidant capacity of mature green tomato. Results indicated that tomato subjected to high TF (15 ± 5°C) had higher respiration rate and weightlessness rate, earlier ethylene release peak, and developed rapid color transfer greater than that to 15 ± 0°C. Besides, tomato exposed to high TF (15 ± 5°C) reveal low lycopene, total phenols, and ascorbic acid content, and inferior activity of superoxide dismutase and catalase later in the storage period. Indicated in this study is the fact that a consistent storage temperature (15 ± 0°C) helps to delay ripening and the senescence process of mature green tomato, and a good sensory quality and high antioxidant capacity after storage is maintained. Practical applications: Storage temperature fluctuation in cold chain logistics of fresh fruits and vegetables is one of the main factors leading to quality loss. In this experiment, the effects of different temperature fluctuations on ripening quality and antioxidant properties of mature green tomato were evaluated. The results showed that the high TF would lead to the abnormal ripening of tomatoes and reduce the ripening quality and antioxidant capacity, while the constant storage temperature had the opposite effect. Operators should ensure as far as possible that the temperature of any link in the cold chain logistics of fresh food is stable, so as to extend the full‐ripening time of green mature tomato after harvest, and improve their edible quality and antioxidant capacity. [ABSTRACT FROM AUTHOR]

Daqu is an important saccharification starter in the brewing of Chinese Baijiu. The evolution of microbial communities and flavor formation are similar among different batches of Daqu , but the drivers of microbial community succession, the composition of functional microbiota, and metabolic pathways are still unclear. To this end, the microbial community succession, physicochemical properties and volatile metabolites dynamic changes and their correlation during the fermentation process of Taorong-type Baijiu Daqu were analyzed. The results showed that the core microbial genera observed in the whole period were Bacillus , Kroppenstedtia , Microbacterium , Thermoascus , Saccharomycopsis , and Apiotrichum. The correlation analysis showed moisture content and acidity drove the evolution of functional microbial communities in the Daqu. Visualized network analysis demonstrated that changes in the relative abundance of functional microbiota such as Bacillus , Kroppenstedtia , Thermomonas , Saccharomycopsis , Thermoascus and Malassezia promoted the difference of metabolism in different stages of Daqu fermentation. PICRUSt2 prediction and volatile metabolite metabolic pathway enrichment analysis showed that the metabolism of Daqu fermenting microorganisms was concentrated on amino acid, carbohydrates and energy metabolism. Our findings will facilitate the standardized production of stable-quality Daqu , and theoretically underlie Baijiu brewing microecological assembly and directional controllable fermentation. • Dynamic changes of microbial community during fermentation of Taorong-type Baijiu Daqu were detected. • Bacillus , Kroppenstedtia , Thermoascus , Saccharomycopsis , Thermoascus and Malassezia are the functional microbiota in Daqu. • Moisture, acidity and microbial interactions drive the succession of the microbial community. • Microbial metabolism was significantly enriched to amino acids, carbohydrates and energy related metabolic pathways. [ABSTRACT FROM AUTHOR]

In order to study the resistance of microstructural characteristics and the changes of physical and chemical indexes in cherry tomatoes during its storage period, fresh cherry tomatoes were treated with high O2 (40%, 60%, 80%, and 100%). The results showed that pure oxygen treatment inhibited the decay rate of tomato significantly, delayed the improvement of membrane permeability, reduced lipid peroxide content, and maintained a good cell structure. Compared with the control, the tomato with 100% oxygen concentration treatment obtained the best results after 28 days of storage, which reflected in that the decay rate is only 30%, titrable acidity (TA) decreased by 53%, malondialdehyde (MDA) was 3.8 mmol/kg and lycopene was 3.1 mg/100 g, and smallest increase of electrical conductivity from 24% to 45%. High concentration oxygen could avoid the anaerobic respiration of tomato to some extent and reduce the production and accumulation of acetaldehyde, ethanol, and ethyl acetate. Practical applications: High oxygen (21%–100% O2) processing technology, developed in recent years, is one of the postharvest processing techniques of fruit and vegetables. Metabolism of cherry tomatoes after picking was deeply modified by the application of high oxygen, which inhibited the decay and delayed the ripening. Cherry tomatoes exposed to high oxygen concentration (100% O2) were shown to have a lower increase in relative electrolyte leakage rate and lipid peroxidation as well as lower membrane damage. High O2 treatment technology is expected to develop into a new concept of controlled atmosphere storage technology, which will play a significant role in fruit and vegetables in storage. [ABSTRACT FROM AUTHOR]

• 1% and 3% CO 2 pulsed controlled atmosphere can delay the loss of fruit water-core • There is the best effect of 1% CO 2 on maintaining the overall visual and sensory quality of fruit • The endurance of watercored apples to 5% CO 2 is less than 45 days • The internal browning of fruit is related to unstable membrane system and dense cell arrangement Watercored 'Fuji' apple with special water core and unique flavor is a characteristic fruit. However, the problems of water core disappearance and browning in the apples are outstanding during postharvest storage. In this study, pulsed controlled atmosphere (pCA) with CO 2 was used to protect the water-core and resist browning of apples. Effects of different concentrations of CO 2 on the quality of apple fruits was investigated, and CO 2 injury characteristic to apple fruits were studied as well. Results showed that pCA with CO 2 could effectively maintain the sensory and texture qualities of watercored apples. Treated with pulsed controlled CO 2 , the degree of membrane lipid peroxidation of the apples was effectively reduced and the membrane system was well maintained. Meanwhile, the activity of polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) of the apples were inhibited and the browning was reduced. On the whole, pCA with 1% CO 2 presented the most significant effects on the quality preservation of watercored apples while higher CO 2 showed negative effects on the quality of the samples. Under the condition of pCA with 5% CO 2 , the endurance of watercored apples was less than 45 days and the internal browning was serious. In conclusion, 2%～3% O 2 and pCA with 1% CO 2 was the best and most effective in the long-term preservation of watercored apples, and it is beneficial to guide for the preservation of apple fruits. [ABSTRACT FROM AUTHOR]

• Combined 1-MCP and sterilizing medium is an effective preservation technology. • 1-MCP + O 3 treatment effectively delayed the softening and senescence of fruit. • 1-MCP + O 3 treatment could induce resistance of fruit at earlier shelf storage. • 1-MCP + O 3 could maintain brighter color attributes of peaches during shelf life. • At the end of storage, 1-MCP + O 3 maintained the best integrity of flesh tissue. Physiological senescence and quality deterioration of peach after harvest were the restrict factors of peach shelf quality. As an ethylene inhibitor, 1-Methylcyclopropene (1-MCP) can effectively dealy fruit ripening and senescence, and improve storage quality. However, studies showed that the effect of fruit preservation by only using 1-MCP is unsatisfactory. Therefore, in this study, 1-MCP combined with sterilizing medium including ozone, TiO 2 photocatalytic and epsilon-polylysine (ε-PL) was applied for enhancement of preservative ability with safety and pollution-free. The flow microcirculation was used for enhancing the effect of sterilizing medium. Results showed that all these three treatment methods can enhance the shelf quality of peach fruit. Among them, the combination treatment of 1-MCP and ozone played a more active role in inhibiting decay, respiration, ethylene production, decline of nutrients such as organic acids and soluble solids. Moreover, it maintained bright color value and cell integrity of peach fruit. In addition, the combined treatment of 1-MCP and ozone had significant effects on inducing resistance in fruit and slowing down membrane lipid peroxidation. In conclusion, 1-MCP combined with ozone was an effective method to delay the senescence and improve the storage shelf quality of fruit, which is beneficial to the guidance of production practice and has potential application prospects in fruit preservation. [ABSTRACT FROM AUTHOR]