不同熟化方式对速冻熟紫薯品质的影响

为深入研究冻前不同熟化方式对速冻熟紫薯品质的影响，本实验以‘紫罗兰’紫薯为原料，采用蒸制、微波制和烤制3种熟化方式处理速冻熟紫薯，并对挥发性成分、色泽、微观结构、花色苷含量和抗氧化活性等进行分析。结果表明，不同熟化方式能够引起速冻熟紫薯中挥发性风味物质的重新分布，提供更多的芳香气味和独特的风味。熟化处理使速冻熟紫薯内组织结构发生变化，使其更易于消化，同时不同熟化处理紫薯花色苷含量也有显著差异，其中蒸制熟紫薯达4.12 mg/g，与鲜紫薯（3.36 mg/g）相比显著提高（P<0.05）。经液相色谱串联质谱（liquid chromatography tandem mass spectrometry,LC-MS/MS）分析鉴定出的紫薯花色苷共有六大类，主要是芍药色素和矢车菊素，蒸制熟紫薯中芍药花素占比最大，达到总量的84.12%，较好地保留了紫薯营养成分和色泽。此外，熟化处理还提高了速冻熟紫薯中花色苷在胃肠消化过程中的释放量，进而显著提高了其抗氧化活性（1,1-二苯基-2-三硝基苯肼自由基清除率、2,2-联氮基双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除率和O2-·清除率），...

Effects of Different Cooking Methods on the Quality of Quick-Frozen Cooked Purple Sweet Potato

The effects of different cooking methods namely, steaming, microwave and roasting on the quality of quick-frozen cooked purple sweet potatoes (cv. Ziluolan) were investigated by measuring its volatile components, color, microstructure, anthocyanin content and antioxidant activity. The results showed that different cooking methods affected the volatile flavor composition of frozen cooked purple potatoes, providing more aroma compounds and a unique flavor. After cooking, the internal structure of frozen cooked purple sweet potatoes changed, making it easier to digest, and there were significant differences in the anthocyanin contents of purple potatoes processed by different cooking methods; the anthocyanin content of steamed purple sweet potatoes was 4.12 mg/g, which significantly higher than that of fresh purple sweet potatoes (3.36 mg/g) (P < 0.05). Six categories of purple sweet potato anthocyanins were identified by liquid chromatography tandem mass spectrometry (LC-MS/MS), the major ones being paeoniflorin and cornflowerin, and the proportion of paeoniflorin in steamed purple sweet potatoes was largest (84.12%), suggesting better preservation of nutrients and color. In addition, cooking increased the release of anthocyanins from quick-frozen cooked purple sweet potatoes during gastrointestinal digestion, which in turn significantly improved the antioxidant activities (1,1-diphenyl-2-trinitrophenylhydrazine (DPPH) radical scavenging capacity, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radical scavenging capacity and superoxide anion radical scavenging capacity) and inhibited the activity of digestive enzymes (α-amylase and α-glucosidase), while changing the acylation rate and improving the stability of purple sweet potato anthocyanins. It was concluded that steaming could better stabilize anthocyanins in quick-frozen cooked purple sweet potatoes, imparting it with good storage stability. This study can provide a theoretical reference for the development of convenience purple sweet potato foods.