红枣膳食纤维酶法提取工艺优化及其抗氧化研究

以新疆红枣为研究对象,通过单因素试验及响应面试验优化红枣膳食纤维酶法提取工艺,并对其理化性质及抗氧化特性进行测定和评价。结果发现,当酶添加量为1.5 mg·mL-1,酶解温度为50℃,液料比为9:1 mL/g,酶解时间为45 min时,红枣膳食纤维酶法提取率最高,达到9.18%,与预测值误差仅为0.33%。酶法提取与热水浸提相比,其持水力、持油力、膨胀力、阳离子交换能力等指标均有不同程度的提升,且均存在显著性差异(P<0.05)。抗氧化性研究结果显示,红枣膳食纤维对DPPH·有较强的清除能力,IC₅₀为0.227 mg·mL-1,显示了其较高的体外抗氧化活性,可以作为天然抗氧化剂进行开发。

Optimization of Enzymatic Extraction of Dietary Fiber from Zizyphus jujube and Its Antioxidant Activity

The dietary fiber was extracted from Zizyphus jujube.The processing of enzyme extraction of dietary fibers was studied by single factor experiments and response surface analysis method. The optimal process parameters of the extraction process were:Enzyme volume 1.5 mg·mL-1,temperature 50℃,liquid to solid ratio 9:1 mL/g and extraction time 45 min. Under these conditions,the yield of dietary fiber from Zizyphus jujube was 9.18%. The water-holding capacity,oil-holding capacity,expansive force and cation exchange capacity of enzyme extraction were stronger than water extraction with significant differences(P<0.05). The dietary fiber from Zizyphus jujube revealed strong scavenging capacity against DPPH free radicals with an IC₅₀ was 0.227 mg·mL-1.The study revealed that the dietary fiber from Zizyphus jujube had high antioxidant activity in vitro and could be used as a natural antioxidant.