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The organic acids and amino acids of 88 samples of apricot seed kernels from southern Xinjiang were determined by gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography (HPLC). The results showed that the content of total organic acids ranged from 23.75 to 11 446.19 μg/g, malic acid comprising the highest proportion (46.66%) of the total, followed by oxalic acid (14.67%) and citric acid (12.06%), and gluconic acid accounting for the lowest proportion (0.05%). Oleic acid was the predominant unsaturated fatty acid, accounting for 59.91% of the total fatty acids; and palmitic acid was the major saturated fatty acids, accounting for 12.57% of the total fatty acids. A total of 15 amino acids were detected in all samples, the total amino acid content was 79.55–4 464.17 μg/g, and the essential amino acid content was 21.62–1 248.35 μg/g. The results of principal component analysis (PCA) showed that the cumulative variance contribution rate of the first eight principal components for acid compounds was 85.05%, and malic acid, citric acid, valine, threonine, glutamine, serine, oleic acid, linoleic acid, succinic acid and acetic acid important indexes for evaluating the quality of apricot seed kernels. The samples were clustered into four groups based on the contents of 31 polar metabolites. The first group consisted of eight samples, which were abundant in malate, fatty acid and glutamate. The second group included 77 samples, which were moderate in malic acid and fatty acid and low in amino acids. The third group included ‘Zao Da You Xing’ and ‘Lopu 2’, which had high succinic acid content, moderate fatty acid content and low amino acid content. The final group included ‘Wan Shu Hei Ye Xing’, characterized by the highest succinic acid content, low fatty acid content and high amino acid content.

Blueberry juice has been found to undergo severe browning after treatment and cold storage, such as processing by high hydrostatic pressure (HHP) at 550 MPa/10 min/25 °C followed storage at 4 °C for 4 days. This browning may be due to the degradation of anthocyanin (AC) in the berries. Therefore, in this study, gallic acid (GA), ferulic acid (FA), ascorbic acid (VC), citric acid (CA), tea polyphenol (TP) and α-tocopherol (VE) were compared to determine their ability to improve the stability of the AC in HHP-treated blueberry juice. The juice was combined with the six abovementioned antioxidants at different concentrations, then treated by HHP at 550 MPa/10 min/25 °C and stored at 4 °C for 20 days. Thereafter, the pH levels, degrees °Brix, color parameters, total AC content and polyphenol oxidase (PPO) activity of the blueberry juice blend were measured and compared. Gallic acid at 2 g/L was found to be the most effective antioxidant to protect against AC degradation. After storage at 4 °C for 20 days, the AC content of the juice with no added antioxidants had decreased by 62.27% with a PPO relative activity of 50.78%, while the AC content of juice supplemented with 2 g/L GA had decreased by 13.42% with a PPO relative activity of 28.13%. The results of this study, thus, suggest that GA can stabilize the structure of AC in blueberry juice and reduce PPO activity, which may be beneficial in guiding the production of blueberry juice with high AC retention. [ABSTRACT FROM AUTHOR]

This study synthesized titanium dioxide (TiO2) nanoparticles (NPs) from mango leaf extract and investigated the features and antibacterial capabilities of three different. The microscopic morphological observation, scanning electron microscopy, and transmission electron microscopy results showed that all three NPs showed agglomeration phenomenon, and the TN‐1 sample existed as large agglomerates, whereas the agglomeration phenomenon of TN‐3 sample was improved by the modified, without large agglomerates. The biosynthetic TN‐2 and TN‐3 NPs were spherical and uniform in size, whereas those of the TN‐3 sample was the smallest, ranging from 10 to 30 nm. X‐ray diffraction and Raman spectroscopy results exhibited that these were highly pure anatase NPs. The result of ultraviolet (UV)–visible–near‐infrared spectral analysis showed that the TN‐2 and TN‐3 samples displayed higher UV absorption properties than the TN‐1 samples and were highest in the modified NPs, which was more suitable for preparing chitosan‐based nanocomposite material in future experiments and studies. The colony diameters of the TN‐1, TN‐2, and TN‐3 treatment groups were 7.99, 7.80, and 6.86 mm, respectively, after 120 min of UV light induction at a wavelength of 365 nm. Significant differences were evident between the TN‐3 and the other two groups (p < 0.05), indicating that the TN‐3 sample more effectively inhibited Penicillium steckii than the other TiO2 NPs. Practical Application: Nanomaterials coated film preservation is widely used in fruit and vegetable preservation. In this paper, TiO2 nanomaterials will be green synthesized using mango leaf and structurally characterized, whereas antibacterial tests will be conducted against the mango fruit–specific bacterium Penicillium steckii, which will provide a theoretical basis for the storage and preservation of mango. [ABSTRACT FROM AUTHOR]

A starch‐rich portion is produced as a by‐product of black Tartary buckwheat processing. The effect of enzymatic combined with autoclaving–cooling cycles (one, two, or three times) on the physicochemical and structural properties of black Tartary buckwheat type 3 resistant starch (BRS) was evaluated. The autoclaving–cooling cycles enhanced solubility and reduced swelling, with the BRS content increasing from 14.12% to 25.18%. The high crystallinity of the BRS reflected a high molecular order. However, increasing the number of autoclaving–cooling cycles did not result in higher BRS content. The highest BRS yield in the autoclaved starch samples was 25.18% after double‐autoclaving–cooling cycles. Furthermore, the autoclaving–cooling cycles altered the crystalline structure of black Tartary buckwheat, and the subsequent crystallinity changed from 36.33% to 42.05% to 38.27%. Fourier‐transform infrared spectroscopy shows that the number of cycles results in more efficient double‐helical packing within the crystalline lamella. Principal component analysis showed that the autoclaving–cooling cycle treatment leads to significant changes in the molecular structure of resistant starch (RS). These results indicated that autoclaving–cooling cycles might be a feasible way for producing RS from black Tartary buckwheat starch with better structural stability to expand their application range. [ABSTRACT FROM AUTHOR]