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The quality and shelf life of mushrooms are critical to their commercial viability. In this study, the effects of simulated transport vibration on postharvest quality of shiitake mushrooms (Lentinus edodes) were assessed over 12 days of storage. Furthermore, the protective performance of foam cushion material used in packaging during simulated transport was evaluated. Changes in respiration rate, weight loss, browning index, firmness, and malondialdehyde content were measured following vibration treatment. The results revealed that simulated transport vibration contributed to the deterioration of quality of shiitake mushrooms during storage, and the foam cushion material had a protective influence on the maintenance of shiitake mushroom quality. Taken together, our findings suggest that the foam cushion material used in packaging has the potential to improve the quality of shiitake mushrooms and extend their shelf life., Vibrations caused quality deterioration of shiitake mushroom. Foam cushion material delayed quality deterioration.

HighlightsThree antioxidant peptides were efficiently obtained from large yellow croaker scales.The molecular weights of the three peptides were 879.4, 952.5, and 1070.4 Da, respectively.The large yellow croaker scales’ hydrolysates are a good source of natural antioxidants.Abstract. The scales of large yellow croaker () are typically discarded as waste during processing. In this study, three peptides with high antioxidant properties were purified from the scales via ultrafiltration and column chromatography. Through matrix-assisted laser desorption ionization/time-of-flight mass spectrometry, the sequences of the three peptides were identified as Gln-Arg-Pro-Pro-Glu-Pro-Arg (M1N4-1, 879.4 Da), Glu-Lys-Val-Trp-Lys-Tyr-Cys-Asp (M1N4-2, 1070.4 Da), and Val-Gly-Leu-Pro-Gly-Leu-Ser-Gly-Pro-Val-Gly (M2N2-1, 952.5 Da). The antioxidant activity of the peptides was directly determined through 1-diphenyl-2-picrylhydrazyl scavenging assay. Results suggested that large yellow croaker scales are a good source of natural antioxidants. Keywords: Antioxidant peptide, Hydrolysis, Pseudosciaena crocea, Scale.

In this study, the physiochemical properties of corn oil and its oxidative stability in an O/W emulsion were studied following short‐term (120 min) deep‐frying of chicken wing. The results showed that the levels of polyunsaturated fatty acids in corn oil decreased after frying. Furthermore, total polar compound content in frying oil was significantly increased to 11.3%. Fourier transform infrared spectra (FTIR) indicated that hydrolysis and oxidation reactions involving triglycerides occurred after frying. Additionally, the increased a* and b* values demonstrated that deep‐frying greatly enhanced the intensity of the red and yellow colors of corn oil. Frying reduced the oxidative stability of corn oil in an O/W emulsion as determined by the peroxide value and acid value. These findings indicated that short‐term deep‐frying of chicken wing deteriorated the quality of corn oil and decreased its oxidative stability in an O/W emulsion. Consumers should consider the potential hazards of food containing short‐term deep‐frying oil., Short‐term deep‐frying of chicken wing deteriorated the quality of corn oil and decreased its oxidative stability in an O/W emulsion. Consumers should consider the potential hazards of food containing short‐term deep‐frying oil.

Phytochemical-enriched edible greens, sweet potato leaves (Ipomoea batatas L.), have become popular due to potential health benefits. However, the phytochemical contents in sweet potato leaves and their subsequent change over harvest stages and growth condition are mostly unknown. In this study, the anthocyanin profile and content in leaves of four sweet potato cultivars, i.e., white-skinned and white-fleshed Bonita, red-skinned and orange-fleshed Beauregard, red-skinned and white-fleshed Murasaki and purple-skinned and purple-fleshed P40, were evaluated. Fourteen anthocyanins were isolated and identified by HPLC-MSI/MS. The most abundant was cyanidin 3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside, which comprised up to 20% of the total anthocyanins. Of the young leaves (1st and 2nd slip cuttings), Bonita contained the highest anthocyanin content followed by P40. Of the mature leaves (vine stage), Beauregard had the greatest anthocyanin (592.5 ± 86.4 mg/kg DW) and total phenolic (52.2 ± 3 mg GAE/g DW). It should be noted that the lowest anthocyanin and total phenolic content of shoots were found in P40, while tubers of P40 contain the highest content of each. Furthermore, the increase in leaf anthocyanin content over the growth stages that was observed in three of the cultivars but not in P40. No significant difference of anthocyanin content was found in Beauregard leaves grown in the high tunnels when compared with that in the open field. This study demonstrated for the first time that anthocyanin levels were significantly changed in response to various growth stages but not high tunnel condition, indicating that the effect of anthocyanin biosynthesis in sweet potato leaves is highly variable and genotype specific.

Soy protein isolate (SPI) has promising applications in various food products because of its excellent functional properties and nutritional quality. The structural and emulsifying properties of covalently modified SPI by (-)-epigallocatechin-3-gallate (EGCG) were investigated.; Results: SPI was covalently modified by EGCG under alkaline conditions. SDS-PAGE analysis revealed that EGCG modification caused crosslinking of SPI proteins. Circular dichroism spectra demonstrated that the secondary structure of SPI proteins was changed by EGCG modification. In addition, the modifications resulted in the perturbation of the tertiary structure of SPI as evidenced by intrinsic fluorescence spectra and surface hydrophobicity measurements. Oil-in-water emulsions of modified SPI had smaller droplet sizes and better creaming stability compared to those from unmodified SPI.; Conclusion: The covalent modification by EGCG improved the emulsifying property of SPI. This study therefore provided an innovative approach for improving the emulsifying properties of proteins. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

The physicochemical and functional properties of covalently modified whey protein isolate (WPI) by (−)-epigallocatechin-3-gallate (EGCG) were investigated. WPI was chemically modified by EGCG under alkaline conditions. The effect of modification on foaming and emulsifying properties was evaluated. The results of SDS-PAGE and size exclusion chromatography indicated that modification by EGCG induced cross-linking on proteins of WPI. Fourier transform infrared spectroscopy (FT-IR) analysis illustrated the incorporation of phenolic groups into the modified WPI and the changes in protein secondary structure. Intrinsic fluorescence spectra revealed that modified WPI had a more compact tertiary structure compared to unmodified WPI. The modified WPI exhibited better foaming and emulsifying properties than unmodified WPI. These results suggest that EGCG modification is a potential method for improving the functional properties of WPI.

β-lactoglobulin (β-lg), the predominant protein in bovine whey, was chemically modified by (-)-epigallocatechin-3-gallate (EGCG) to develop a biomacromolecule with antioxidant activity. The EGCG-modified β-lg was characterized by SDS-PAGE, MALDI-TOF MS and intrinsic fluorescence spectroscopy. The antioxidant properties of EGCG-modified β-lg was assessed using DPPH radical scavenging activity, iron chelating ability, and inhibition of Cu2+-induced LDL oxidation. SDS-PAGE and MALDI-TOF MS results indicated the dimerization of β-lg after EGCG modification. Intrinsic fluorescence spectra suggested that EGCG modification caused an alteration in the conformational structure of β-lg. The results demonstrated that EGCG-modified β-lg possessed great antioxidant potential in terms of scavenging DPPH radical and chelating ferrous ion. Furthermore, the EGCG-modified β-lg showed a protective effect against LDL peroxidation. The results indicate that EGCG-modified β-lg could provide significant health benefits as an antioxidant.

Soy protein isolate (SPI) has promising applications in various food products because of its excellent functional properties and nutritional quality. The structural and emulsifying properties of covalently modified SPI by (-)-epigallocatechin-3-gallate (EGCG) were investigated.SPI was covalently modified by EGCG under alkaline conditions. SDS-PAGE analysis revealed that EGCG modification caused crosslinking of SPI proteins. Circular dichroism spectra demonstrated that the secondary structure of SPI proteins was changed by EGCG modification. In addition, the modifications resulted in the perturbation of the tertiary structure of SPI as evidenced by intrinsic fluorescence spectra and surface hydrophobicity measurements. Oil-in-water emulsions of modified SPI had smaller droplet sizes and better creaming stability compared to those from unmodified SPI.The covalent modification by EGCG improved the emulsifying property of SPI. This study therefore provided an innovative approach for improving the emulsifying properties of proteins. © 2018 Society of Chemical Industry.

A compact and high sensitivity sensor with a fiber-tip structure is proposed and demonstrated for simultaneously liquid refractive index (RI) and temperature sensing. The device is fabricated by inserting a tiny segment of capillary tube between single-mode fibers (SMFs) to form two cascaded Fabry-Perot interferometers (FPIs). The theoretical and experimental results demonstrate that the ambient liquid RI and temperature can be simultaneously determined by the intensity and shift of the resonant wavelength in the reflection spectrum. Our proposed device has the highest RI sensitivity of ~216.37 dB/RIU at the RI value of 1.30; a high spatial resolution owing to its compact size (with dimension