超高压处理对柚皮海绵层不溶性膳食纤维理化性质、结构和抗氧化活性的影响

Effect of ultrahigh-pressure treatment on physicochemical properties, structure, andantioxidant activity of insoluble dietary fiber from pomelo peel sponge layer

该研究解析了超高压处理(600 MPa, 15 min)对3种柚皮海绵层不溶性膳食纤维(insoluble dietary fiber, IDF)理化性质、结构以及抗氧化活性的影响规律。结果表明,超高压处理显著提高了3种柚皮海绵层IDF的溶胀力,其中琯溪蜜柚柚皮海绵层IDF的溶胀力(78.03 mL/g)最高。然而过高的压力会严重破坏膳食纤维的内部结构,导致柚皮海绵层IDF持水力和持油力下降。超高压处理后柚皮海绵层IDF微观结构更加疏松,并显著提高了柚皮海绵层IDF葡萄糖、木糖、阿拉伯糖和半乳糖的含量。通过X-射线衍射发现超高压处理后柚皮海绵层IDF的结晶度降低;傅里叶变换红外光谱显示,超高压处理对柚皮海绵层IDF活性基团种类影响较小,但对其特征峰的吸收强度影响较大。此外,柚皮海绵层IDF经超高压处理后ABTS阳离子自由基和DPPH自由基清除率均有所下降,表明其抗氧化活性降低。以上研究结果表明,超高压处理可改变柚皮海绵层IDF的理化性质、结构和抗氧化活性。该研究为柚皮海绵层IDF的多元化利用提供理论和技术支撑。

In this study,the effects of ultrahigh-pressure(UHP,600 MPa,15 min)treatment on the physicochemical properties,structure,and antioxidant activity of insoluble dietary fiber(IDF)in the spongy layer of three types of pomelo peels were investigated.Results showed that the UHP significantly increased the swelling ability of the pomelo peel spongy layer IDF,and the highest swelling ability(78.03 mL/g)was found in Guanxi pomelo peel sponger layer IDF.However,the high pressure severely damaged the internal structure of the IDF,resulting in a decrease in the water and oil holding capacity of the pomelo peel spongy layer IDF.The microstructure of the IDF in the pomelo peel sponger layer was more loosely packed after the UHP treatment,and the contents of glucose,xylose,arabinose,and galactose in the pomelo peel spongy layer IDF were significantly increased.X-ray diffraction revealed that the crystallinity of the pomelo sponge layer IDF was decreased after the UHP treatment.Moreover,the FT-IR spectra showed that the UHP treatment had less effect on the types of active groups of the pomelo sponge layer IDF,while the absorption intensity of its characteristic peaks was greatly influenced by UHP treatment.In addition,the ABTS cationic radical and DPPH free radical scavenging capacities of the pomelo peel spongy layer IDF were decreased after UHP treatment,suggesting that UHP treatment could reduce its antioxidant activity.Results indicated that UHP treatment could modify the physicochemical properties,structure,and antioxidant activity of pomelo peel spongy layer IDF,which provided theoretical and technical support for the diversified use of the pomelo peel spongy layer IDF.