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In this study, liquid-liquid extraction-solvent assisted flavor evaporation (LLE-SAFE), headspace solid phase microextraction extraction (HS-SPME), gas chromatography-quadrupole-mass spectrometry (GC-Quadrupole-MS), gas chromatography-orbitrap-mass spectrometry (GC-Orbitrap-MS) and gas chromatography-olfactometry (GC-O) were used in combination to identify the volatile components in a fermented hawthorn wine (SBL-J) and a prepared hawthorn wine (FS), and the results of sensory analysis, modified frequency (MF) and odor activity value (OAV) were used to determine the key aroma compounds. Totally 89 aroma compounds were identified by LLE-SAFE/GC-O-MS. In addition, 29 and 38 aroma compounds with MF values of more than 20% were found in SBL-J and FS, respectively. A total of 123 volatile components were detected by HS-SPME/GC-Quadrupole-MS and HS-SPME/GC-Orbitrap-MS and there were 29 and 33 aroma compounds with OAV of greater than 1 (0.1 for esters) identified in SBL-J and FS, respectively. 2-Methybutyl acetate, ethyl hexanoate, ethyl octanoate and phenylethyl alcohol were the key aroma compounds in the two samples. To our knowledge, 2-methybutyl acetate, ethyl isovalerate, (E,E)-2,4-hexadienoic acid ethyl ester and ethyl butyrate, were identified for the first time as the key aroma components of hawthorn wine.

To examine the variances in volatile organic compounds (VOCs) and sensory attributes across various hop cultivars, an analytical approach was employed. Specifically, gas chromatography-ion mobility spectroscopy (GC-IMS), gas chromatography-mass spectrometry (GC-MS), and quantitative descriptive analysis (QDA) were employed to scrutinize the VOCs and sensory characteristics of four distinct hop varieties, namely Magnum, Palisade, Saaz, and Hersbrucker. The outcomes of QDA revealed a diverse array of sensory profiles in the hops, encompassing citrus and non-citrus fruit aromas, woody, floral, herbal, spicy, and green aromas, with noticeable distinctions in sensory attributes discernible among the various hop cultivars. The results showed that 79 VOCs were identified in the GC-IMS spectra of different varieties of hops, including terpenes, alcohols, esters, aldehydes, and ketones. 140 VOCs were identified in the GC-MS spectra of different varieties of hops, including terpenes, alcohols, ketones, esters, acids, and aldehydes, with terpenes and esters emerging as the prevailing constituents in hops. The principal component analysis (PCA) of different hop VOCs was performed to effectively identify the differences among hop varieties. This study can provide a valuable reference for the comprehensive analysis of VOCs and sensory attributes in hops. Furthermore, it contributes theoretical underpinnings to inform the precise application of hops in the context of beer brewing. [ABSTRACT FROM AUTHOR]

[Objective] Available water for irrigation in Hetao irrigation district has been reduced consistently over the past decades. Improving its water management to alleviate soil salinity is critical to sustaining crop production in this region. The purpose of this paper is to seek optimal water-saving irrigation schemes for this region by using process-based models. [Method] The semi-distributed hydrological model (SahysMod) is used in our study. We consider spatial variability of numerous factors in the modelling, which include meteorology, hydrogeology, soil, irrigation and crops. The model is then combined with GIS to simulate the spatiotemporal dynamics of soil water and salt under different scenarios. Data measured from 2007 to 2012 and 2013-2016 were used to calibrate and verify the model, respectively. [Result] ①In a business as usual scenario, the annual drainage decreases first before gradually stabilizing, with the average annual drainage being 531 million m³; salinized lands in the middle and upper reaches of the irrigation district decrease slightly, but increase significantly in the lower reach. ②Considering water-saving in the whole irrigation district and ecological demand for water in the downstream and the Wuliangsuhai lake, the total water diversion from the canal head should be reduced by 15% from the current level. This will save up to 646 million m³ of water. ③If the current irrigation amount remains unchanged, the water utilization coefficient of the canal can be improved 17.6% at the best. ④If the reduction in total water diversion from Yellow River is the same, reducing irrigation amount in the field is the best way to boost salt leaching. In this scenario, reducing irrigation amount should be the priority, followed by improving water utilization coefficient of the canal. [Conclusion] In addition to saving water, considering ecological demand of the downstream for water is also important in optimizing water management in Hetao Irrigation District. [ABSTRACT FROM AUTHOR]