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In order to explore the differences in the aroma quality of different white-fleshed peach cultivars, an electronic nose and headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to analyze the volatile components of eight cultivars of white-fleshed peach including Baiyintao (BYT), Longmi 5 (LM5H), Xinchuanzhongdao (XCZD), Qiutong (QT), Xindajiubao (XDJB), Yihongmi (YHM), Yihongshuimi (YHSM) and Okayama (GSB). Relative odor activity value (ROAV) and variable importance in projection (VIP) were used to analyze the contribution of each volatile component to the overall aroma of white-fleshed peaches. In the electronic nose radar fingerprint, the W1W, W5S, W1S and W2W sensors showed different responses to the eight cultivars. Principal component analysis (PCA) demonstrated differences in the overall aroma of white-fleshed peach cultivars. In total, 49, 46, 46, 47, 49, 47, 47, 53 volatile compounds were identified in BYT, LM5H, XCZD, QT, XDJB, YHM, YHSM, and GSB by HS-SPME-GC-MS, respectively, the major ones being aldehydes, alcohols, lactones and esters. 2-Hexenal, hexanal, trans-2-hexenal and trans-2-hexen-1-ol, contributing to grass aroma; linalool, contributing to floral aroma; and n-hexanol, responsible for fruity aroma, were identified as key aroma compounds due to their ROAV ≥ 1 and VIP > 1. Variations in their concentrations caused differences in the key aroma of the eight white-fleshed peach cultivars.

To identify structures and differences in physiological activity of polysaccharides from different Hovenia dulcis tissues, three populations of H. dulcis polysaccharides (HDP), including whole fruit polysaccharides (HDPW), seed polysaccharides (HDPS) and peduncle polysaccharides (HDPP), were prepared using water extraction and alcohol precipitation. Their structures were analyzed using UV-Vis spectroscopy, high-performance size exclusion chromatography, ion exchange chromatography, Fourier transform infrared spectrometry, and scanning electron microscopy. All three HDP preparations comprised the acidic polysaccharides fucose, rhamnose, arabinose, galactose, glucose, mannose, galacturonic acid, and glucuronic acid in different molar ratios. HDPW, HDPS, and HDPP each eluted in size exclusion chromatography with three chromatographic peaks, and the low and medium molecular weight HDPS peaks (45.72x104~165.75x104 u) displayed higher molecular weights than those of HDPW (0.34x104~12.53x104 u) and HDPP (0.51x104~21.26x104 u). Infrared spectra showed that HDPW and HDPP contained α-glycosidic bonds, while HDPS contained β-glycosidic linked polysaccharides. The respective median inhibitory concentrations of HDP for DPPH free radicals, ABTS free radicals, and α-glucosidase were 0.015~0.043, 0.47~1.21, and 0.13~9.99 mg/mL. When the mass/volume concentrations of HDPW and HDPP were 0.1 mg/mL or above, the glucose consumption rate of insulin-resistant HepG2 cells (IR-HepG2) was significantly increased, with the highest increase compared with the model group being 7.66%. Compared with HDPS, HDPW was similar to HDPP in structure, and both showed better antioxidant and α-glucosidase inhibitory activity and stronger IR-HepG2 glucose uptake promotion ability. This study provides a theoretical basis and data supporting the comprehensive utilization of H. dulcis. [ABSTRACT FROM AUTHOR]

To solve the delamination & precipitation phenomena and to improve the quality of the spray-dried pumpkin powder (PP), the effects of adding mulberry leaf powder (MLP) and oat bran powder (OBP) on the PP quality were investigated. Results showed that POBP (PP + OBP, w:w = 2:1) had lower hygroscopicity (≤42.96 %), which was more homogeneous and stickiness after being brewed, effectively alleviating delamination & precipitation phenomena. Besides, PMLP (PP + MLP, w:w = 2:1) had the highest total phenolic content and total flavonoid content, with the values of 96.92 and 90.50 mg/100 g, respectively. PMLP also exhibited about ten times the antioxidant activity of PP. Furthermore, nine regression equations predicted the antioxidant properties of powders based on soluble solid values and bitterness. Overall, this study indicated that the addition of OBP and MLP improved the stability and nutritional quality of PP, respectively. [ABSTRACT FROM AUTHOR]

Fruits and vegetables contain a large number of volatile compounds, which constitute their unique odor and contribute to their flavor. However, there are only a few key aroma compounds that contribute to the special aroma. How to screen and identify key aroma compounds from many non-contributing and low-contributing compounds has always been the focus and difficulty of the research on the flavor quality of fruits and vegetables. However, it could be better solved via molecular sensory science technology. This review summarizes the application of molecular sensory science technology in fruits and vegetables flavor in recent years, and elaborates the analysis methods related to molecular sensory science, such as sensory evaluation, GC×GC-MS,GC-IMS, GC-O, OAV, omission test and recombination experiment. And some problems existing in current molecular sensory science technology are discussed and prospected. [ABSTRACT FROM AUTHOR]