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The extracts of Lycium chinense Mill fruits with water, 50% ethanol and 95% ethanol were compared in antiradical efficiency according to the Chinese consumption tradition. The results showed that water infusion was similar to 50% ethanol extract in flavonoids (1154 ± 89 and 1207 ± 66 mg kg−1, respectively), 95% ethanol extract contained more flavonoids (1497 ± 70 mg kg−1). The main flavonoids in Lycium chinense Mill fruits were rutin and chlorogenic acid in water extract, rutin and protocatechuic acid in 50% ethanol extract and rutin in 95% ethanol extract as determined with high-performance liquid chromatography (HPLC). All extracts showed a slow kinetics in DPPH⋅ antiradical reaction system. The antiradical efficiency of the extracts tended to become stronger as the polarity of the solvents decreased. [Copyright &y& Elsevier]

The lipase (LA) and peroxidase (POD) activities, as well as morphological structure, physicochemical and digestion properties of sand rice flour (SRF) treated with superheated steam (SS), were investigated. SS treatment at 165 °C completely deactivated LA and resulted in a 98% deactivation of POD activities in SRF. This treatment also intensified gelatinization, induced noticeable color alterations, and decreased pasting viscosities. Furthermore, there was a moderate reduction in crystal structure, lamellar structure, and short-range ordered structure, with a pronounced reduction at temperatures exceeding 170 °C. These alterations significantly impacted SRF digestibility, leading to increased levels of rapidly digestible starch (RDS) and resistant starch (RS), with the highest RS content achieved at 165 °C. The effectiveness of SS treatment depends on temperature, with 165 °C being able to stabilize SRF with moderate changes in color and structure. These findings will provide a scientific foundation for SS applicated in SRF stabilization and modification. [Display omitted] • Superheated steam (SS) treatment deactivates lipase and peroxidase. • SS treatment efficiency depends on the temperature input. • SS treatment is potential for sand rice flour stabilization. [ABSTRACT FROM AUTHOR]

• AC electric field (ACEF) acted on peanut protein isolate (PPI) structure and flavor. • Structure and volatile compounds analyzed quantitatively and qualitatively. • ACEF caused alteration of secondary and tertiary structure. • ACEF promising in improving structure and flavor of PPI. The impacts of intensity and treating time of alternating current (AC) electric field (EF) on structure and volatile compounds of peanut protein were investigated for low denaturation. The secondary and tertiary structures, polar and weakly polar volatiles were characterized qualitatively and quantitatively using ultraviolet and fluorescence photospectrometry, free sulfhydryl and disulfide groups determination, and combination of gas chromatography and mass spectrometry. The results showed that the ACEF affected significantly proportions of α-helices, β-sheets, β-turns, and random coils as evidenced by Fourier transform infrared spectrometry. Blue shifts of UV and fluorescence spectra, increased surface hydrophobicity and disulfide bonds could be observed after ACEF treatments. The DB-WAX and DB-5MS columns for the polar and weakly polar volatile compound separation revealed that ACEF caused either disappearance or emerging of volatile compounds. The PCA demonstrated that the two principal components contributed about 70 % or more to the flavor and PLS-DA discriminated 18 key compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Less than 3% egg white protein affected the properties of highland barely noodles. • Egg white protein improve protein structure through aggregation and cross-linking. • The working mechanism of egg white protein varied among noodle processing stages. • Effect of egg white protein on the highland barely noodles was does-dependent. • Excessive egg white protein decreased noodles quality and deducted protein network. The effect of egg white protein on the protein structure of highland barely noodles during processing was investigated, and the underlying mechanism was examined. Egg white protein significantly influenced the stress relaxation of highland barley dough. 1% and 2% egg white protein improved the cooking and textural properties of highland barely noodles. During mixing and sheeting, it improved the structure of the protein network by promoting protein aggregation and cross-linking, whereas its effect on non-covalent interactions was quite different. During cooking, egg white protein promoted protein aggregation and cross-linking via heat-induced polymerization, and the distribution regularity of the protein network was improved as its flexibility diminished. The protein structure of highland barely noodles during processing was closely related to the addition amount of egg white protein, and the cooking, textural, and chemical interactions of highland barely noodles during processing changed considerably when more than 3% egg white protein was added. [ABSTRACT FROM AUTHOR]

[Display omitted] • Partial gelatinization and freeze-thawing significantly modified the properties of waxy maize starch. • The addition of xanthan gum enhanced these effects of physical treatments. • Treatments affected inner structure and chain arrangement of starch. • Treatments improved the pasting properties and produced a short and cohesive paste. • Treatments increased the gelling ability and stability to freeze-thawing cycles. To improve the pasting and gelling behaviors of waxy maize starch, an aqueous dispersion with or without xanthan gum was subjected to partial gelatinization (5 ℃ above the onset melting temperature of starch) and freeze-thawing treatment. After the treatments, starch granules were slightly deformed, with partial loss of birefringence, and tended to aggregate. The relative crystallinity and thermal stability of waxy maize starch crystals decreased by the treatments. These changes indicated that the treatment affected the inner structure and chain arrangement of the granules. The treated waxy maize starches, however, showed a higher overall pasting viscosity with shorter and more cohesive pastes than that of the native starch. The treated starches formed rigid gels with increased stability against freeze-thawing. The addition of small amounts of xanthan gum enhanced the effects of the treatments. [ABSTRACT FROM AUTHOR]