Extraction Characteristics of Anthocyanins from Preliminarily-processed Products of Purple Sweet Potatoes during the Gelatinization Process

Objective] This study aimed to investigate the method for efficient utilization and development of purple sweet potatoes. [Method] Purple sweet potatoes were dried at two specific temperatures and prepared into preliminarily-processed products for gelatinization simulation to analyze the extraction amount of anthocyanins from gelatinized samples at different gelatinization stages. [Result] During the gelatinization process, the extraction rate of anthocyanins from purple sweet potato samples reached the highest as the temperature rised from 90 ℃ to 95 ℃,and the extraction amount of anthocyanins reached the maximum at 15 min postheat preservation at 95 ℃. Purple sweet potato samples dried at 60 ℃ exhibited larger retention amount, larger maximum extraction amount and higher maximum extraction rate of anthocyanins compared with those dried at 110 ℃. [Conclusion] Drying at low temperatures and appropriately shortening the initial gelatinization stage below 90 ℃ is conducive to the retention and extraction of anthocyanins from purple sweet potatoes.

Optimization of Extraction Process of Anthocyanins from Selenium-enriched Purple Potato by Response Surface Methodology

Ultrasound-assisted extraction method was applied to extract the anthocyanins from selenium-enriched purple potato,and the optimum extraction conditions for anthocyanins in selenium-enriched purple potato were obtained by response surface methodology:the phosphoric acid concentration of 1.0%,the solid-liquid ratio at 5,and the extraction time of 19 min.Under these conditions,the yield of anthocyanins in selenium-enriched purple potato reached(0.409±0.010)mg/g(RSD=2.51%,n=3).The extraction of anthocyanins from selenium-rich fresh purple potato with dilute phosphoric acid has the advantages of less acid consumption and good extraction effect.

Regulation of Anthocyanin during Storage Root Development Stage in Sweet Potato(Ipomoea batatas(L.) Lam.)

Anthocyanin accumulation during storage root development in purple-fleshed sweet potato was analyzed by detection of anthocyanin concentration, accumulation rate and the expression pattern of anthocyanin biosynthetic genes by semi-quantitative RT-PCR. Anthocyanin concentration in sweet potato cvs Jishu 18 and Ayamurasaki increased steadily during storage root development stage. The accumulation rate in two genotypes peaked at 50 to 65 d after transplanting, and then declined rapidly. During storage root development of Ayamurasaki, the anthocyanin biosynthesis gene, IbCHS, was constitutively expressed, the genes IbF3H, IbDFR, IbANS were induced steadily, reaching a maximum at the later stage of root thickening, and IbPAL steadily decreased. Therefore, the mechanism of anthocyanin accumulation differed between the two cultivars, and anthocyanin biosynthesis was regulated through regulation of its synthetic enzymes.

Diacylated anthocyanins from purple sweet potato(Ipomoea batatas L.)attenuate hyperglycemia and hyperuricemia in mice induced by a high-fructose/high-fat diet

Studies have shown that targeting xanthine oxidase(XO)can be a feasible treatment for fructose-induced hyperuricemia and hyperglycemia.This study aimed to evaluate the dual regulatory effects and molecular mechanisms of diacylated anthocyanins from purple sweet potato(diacylated AF-PSPs)on hyperglycemia and hyperuricemia induced by a high-fructose/high-fat diet.The body weight,organ index,serum biochemical indexes,and liver antioxidant indexes of mice were measured,and the kidneys were observed in pathological sections.The relative expression levels of messenger RNAs(mRNAs)of fructose metabolism pathway enzymes in kidney were detected by fluorescent real-time quantitative polymerase chain(qPCR)reaction technique,and the expression of renal transporter protein and inflammatory factor pathway protein was determined by immunohistochemistry(IHC)technique.Results showed that diacylated AF-PSPs alleviated hyperuricemia in mice,and that this effect might be related to the regulation of liver XO activity,lipid accumulation,and relevant renal transporters.Diacylated AF-PSPs reduced body weight and relieved lipid metabolism disorder,liver lipid accumulation,and liver oxidative stress,thereby enhancing insulin utilization and sensitivity,lowering blood sugar,and reducing hyperglycemia in mice.Also,diacylated AF-PSPs restored mRNA levels related to renal fructose metabolism,and reduced kidney injury and inflammation.This study provided experimental evidence for the mechanisms of dual regulation of blood glucose and uric acid(UA)by diacylated AF-PSPs and their utilization as functional foods in the management of metabolic syndrome.

Recent advances on the biological activities of purple sweet potato anthocyanins

Purple sweet potato is one of the main food crops in the tropical and subtropical areas.Purple sweet potato is abundant in anthocyanins,starches,non-starch polysaccharides,caffeoylquinic acid derivatives,vitamins and minerals.Among these components,anthocyanins have been considered as the major biological molecule and are responsible for deep purple color in purple sweet potato.The main chemical structure of purple sweet potato anthocyanins(PSPAs)includes cyanidins and peonidins in the form of monoacylation and diacylation.Owing to heat resistance and ultraviolet stability,PSPAs possess potential applications in the fields of food,cosmetics and pharmaceuticals.Moreover,PSPAs have attracted increasing attention due to their antioxidant,anti-inflammatory,anti-cancer,hypouricemic,hepatoprotective,hypolipidemic,hypoglycemic and neuroprotective activities.This review summarizes recent advances on the health-promoting activities of PSPAs,which will provide a theoretical basis of PSPAs for the development of functional foods.

基于紫薯花青素及明胶构建鸡肉新鲜度智能指示标签

目的开发一种新型明胶基新鲜度指示标签,解决明胶基新鲜度指示膜水溶液稳定性差及天然色素迁移问题,探究二醛基纤维素的添加对指示薄膜稳定性的增益作用,以及复合指示薄膜的新鲜度指示性能。方法以明胶(Gelatin,GE)为成膜基质,以二醛基纤维素(Dialdehyde cellulose,DAC)为交联剂,以紫薯花青素(Purple Sweet Potato Anthocyanins,PSPA)为pH敏感色素,制备了PSPA/DAC/GE复合薄膜,用于指示鸡肉新鲜度。结果红外光谱图(FT-IR)、水溶液稳定性测试等结果表明,DAC的加入能有效降低复合膜的溶胀度和溶解性,并能更好地负载PSPA。将PSPA/DAC/GE用于鸡肉新鲜度监测,针对鸡肉变质过程中产生的氨气,复合薄膜表现出良好的响应性。其中,当PSPA的含量为GE干质量的10%时,指示膜的显色效果最明显。结论成功地将PSPA/DAC/GE复合薄膜用于鸡肉新鲜度的监测,实现了新鲜度可视化,有效降低了消费者接触变质食品的风险,为生产者和消费者提供了更加便捷的生产消费方式。

紫薯粉对莜麦饼干品质的影响

通过添加一定比例的紫薯粉改良莜麦饼干配方,从而提升饼干的感官评价、质构、营养成分含量等指标。通过单因素和正交试验,考察紫薯粉和莜麦粉质量比、黄油添加量以及白砂糖添加量对饼干品质的影响,进而采用验证试验比较改良前后莜麦饼干品质,并通过高分辨率质谱分析添加紫薯粉后莜麦饼干中花色苷含量的变化。根据产品的感官评分以及质构特性,得出改良后的紫薯⁃莜麦饼干的最佳配方为紫薯粉和莜麦粉质量比60∶140、黄油添加量100 g、白砂糖添加量80 g。添加紫薯粉后的莜麦饼干颜色均匀,莜麦的色泽得到改善,质构评分良好,还增添紫薯特殊的香气和风味,感官评分为84.9。改良后的紫薯⁃莜麦饼干中鉴定出20种花色苷,花色苷总含量为0.18 mg/g。

紫色马铃薯糕加工工艺参数优化

以低筋面粉和紫色马铃薯为主要原料制作紫色马铃薯糕,采用单因素和正交试验优化紫色马铃薯糕的最佳加工工艺参数,并以感官评分为指标,对该工艺参数下制作的紫色马铃薯糕进行客观评价。结果表明,制作紫色马铃薯糕的最佳工艺参数为紫色马铃薯与低筋面粉总重200 g,其比例35∶65,绵白糖添加量35 g,酵母粉添加量1.5 g,蒸制时间20 min。该工艺条件下制作的紫色马铃薯糕色泽艳丽且均匀,呈天然紫色,松软有弹性,外形完整饱满,口感细腻,富含花青素,具有较高的营养价值,适合婴幼儿及中老年人食用,极大丰富了糕点类食物的市场多样性,具有较高的推广价值。

紫薯花青素的提取工艺及抗氧化、抗紫外活性研究

目的:探究紫薯花青素提取工艺参数,测定其稳定性和含量,并对其进行抗氧化、抗紫外活性的初步研究。方法:采用单因素试验和正交试验优化紫薯花青素的提取工艺,测定紫薯花青素在不同条件下的稳定性。通过还原力、自由基清除实验和AAPH斑马鱼氧化应激模型评价紫薯花青素的抗氧化活性;通过斑马鱼UVB损伤模型测定紫薯花青素的抗紫外损伤作用。结果:在料液比为1∶15(g/mL)、温度为60℃、溶剂为95%乙醇、超声提取时间为30 min时,紫薯花青素的含量为29.27%;紫薯花青素溶液在温度60℃、pH 4~5、避光条件下稳定性较高。0.03~0.10 mg/mL紫薯花青素溶液具有显著的还原力以及清除羟基和DPPH自由基的能力;0.05 mg/mL紫薯花青素溶液提高了AAPH模型组斑马鱼体内SOD、CAT活力;0.10 mg/mL紫薯花青素溶液修复了UVB照射引起的斑马鱼尾鳍皱缩。结论:紫薯花青素的最佳提取工艺为95%乙醇、料液比1∶15(g/mL)、温度60℃、超声提取30 min,紫薯花青素溶液具有一定的抗氧化以及修复UVB损伤的作用。

含紫薯花青素的槟榔芋淀粉薄膜性能及其应用

开发含紫薯花青素(PSPA)并可生物降解的槟榔芋淀粉薄膜(TSF),并研究其光学性能、厚度、含水率、水溶性、颜色、总酚含量、抗氧化活性、红外光谱和微观结构等性能,初步探讨TSF对鲜切莴笋、鱼肉和猪肉储存过程中新鲜度的指示作用。研究表明TSF的紫外-可见光谱和PSPA溶液的光谱变化规律是一致的,表明PSPA与槟榔芋淀粉具有良好的成膜机制。TSF厚度适中,含水率为39.17%,水溶性为36.93%;TSF的DPPH清除率达到94%,表明TSF的抗氧化活性高。将TSF应用于鲜切莴笋、鱼肉和猪肉的新鲜度监测,TSF先呈现淡紫色,随着时间推移,鲜切莴笋、鱼肉和猪肉逐渐腐败变质,48 h后,TSF在莴笋中呈现蓝紫色、猪肉中呈现浅绿色、鱼肉中呈现淡黄色。

酸性条件下小麦低聚肽增强紫薯花色苷抗氧化性的研究

在pH4.0酸性条件下,添加25~100g/L的小麦低聚肽(WOPs)虽降低了紫薯花色苷(PSPAs)的热稳定性,但两者相互作用增强了其抗氧化能力,并随着其添加量的增加而增大。当添加量为100g/L时,PSPAs溶液在体外模拟消化后的DPPH、ABTS自由基清除能力和总抗氧化能力(FRAP)分别提高了1.5倍、34倍和34%,且分别在37℃和45℃贮藏7d后,其抗氧化能力没有出现显著性降低,相比于单独的PSPAs具有更强的生物活性以及更高的稳定性。紫外光谱和荧光光谱表明在实验浓度下,PSPAs可以引起WOPs特定波长下吸收峰的红移和荧光猝灭,证明WOPs和PSPAs之间存在相互作用。综上可知,WOPs具有应用于酸性PSPAs饮料开发的潜力。

紫马铃薯花色苷提取工艺优化及稳定性、抗氧化活性分析

以甜菜碱为氢键受体,有机酸、糖基和醇基分别为氢键供体制备天然绿色的低共熔溶剂,基于微波辅助提取法,通过单因素实验并结合响应面分析对紫马铃薯花色苷提取工艺进行优化。主要考察了微波时间、微波功率、溶剂含水量、溶剂摩尔比对紫马铃薯花色苷含量的影响。同时比较低共熔溶剂与常规溶剂提取对紫马铃薯花色苷在不同温度、光照条件下的稳定性,以及DPPH、ABTS^(+)、OH自由基清除率评价体外抗氧化能力。结果表明,以甜菜碱和柠檬酸制备酸性低共熔溶剂,摩尔比1:2.1,含水量为28.6%,在微波功率800 W,微波时间28 s条件下,紫马铃薯花色苷含量可达到228.658±1.241 mg/100 g,较常规提取工艺含量提高了56.92%。此外通过低共熔溶剂提取所得花色苷在不同光照、温度条件下稳定性均显著提高。其中太阳光对紫马铃薯花色苷影响最大,避光情况下低共熔溶剂提取花色苷保存率可达90%以上,常规溶剂提取花色苷保存率为82.78%,此外,花色苷含量也随着温度的增加不断降低,二者保存率均明显下降。抗氧化能力结果表明,低共熔溶剂提取所得花色苷抗氧化能力更强,其清除自由基能力IC_(50)值均小于常规溶剂提取。DPPH自由基清除能力IC_(50)值从45.95μg/mL降至41.54μg/mL;ABTS+自由基清除能力IC_(50)值从17.81μg/mL至11.30μg/mL;OH自由基清除能力IC_(50)值从162.00μg/mL至22.44μg/mL。因此紫色马铃薯花色苷含量、稳定性和抗氧化活性与其提取溶剂的选择密切相关,本提取工艺的研究为紫马铃薯花色苷的利用开发提供了新思路。

基于紫薯花青素/茜素的猪肉新鲜度智能指示膜研究

环境因素和微生物污染引起的食品腐败变质,不仅威胁公众健康,还造成食品资源浪费。将天然色素用于制备颜色指示型智能包装,可以监测食品品质变化。该文以羧甲基纤维素和马铃薯淀粉为成膜基材,添加紫薯花青素、茜素及其混合物制备智能指示膜,比较分析了膜的物理性能、机械性能、微观结构、颜色稳定性和pH响应性。结果表明,随着紫薯花青素和/或茜素的添加,羧甲基纤维素/马铃薯淀粉膜的厚度增加、水分含量降低、透光性下降、拉伸强度增加而断裂伸长率降低。扫描电子显微镜结果表明色素的加入使基膜的微观结构更加致密。将负载紫薯花青素和/或茜素的指示膜用于猪肉新鲜度监测,结果表明,在4℃贮藏环境下,随着时间延长,猪肉的pH值和挥发性盐基氮含量不断上升,6 d后均超过可接受限值,表明猪肉开始腐败,指示膜呈现肉眼可见的颜色变化。该研究为肉品新鲜度智能指示膜的开发提供了参考。

富含花青素紫马铃薯汁护色研究及酶解工艺优化

为了提升紫马铃薯汁品质,并为其工业化生产提供基础,该试验通过单因素及田口试验设计对紫马铃薯酶解工艺进行优化,通过单因素及双因素试验对紫马铃薯汁护色条件进行优化。结果表明,紫马铃薯最佳酶解工艺为高温α-淀粉酶0.2%、果胶酶0.3%和纤维素酶0.5%,在此条件下紫马铃薯的可溶性固形物含量为70.3 g/L;最佳紫马铃薯汁护色工艺为添加柠檬酸1.6%和乳清蛋白0.3%,在此条件下紫马铃薯汁花青素含量为102.4 g/L。

k-卡拉胶复合紫薯花青素指示膜的制备及应用

本研究以k-卡拉胶和紫薯花青素为原料,采用溶剂浇铸法在不同pH(即4,5,6,7)条件下制备了pH响应指示膜,并采用紫外可见光谱(UV-vis)和傅里叶红外光谱(FT-IR)对指示膜结构进行表征,同时对薄膜的厚度、力学性能、流变性能及全脂灭菌乳变质监测试验等相关性能进行了评估。结果表明,k-卡拉胶和紫薯花青素可能以静电作用或者氢键作用相结合。对比卡拉胶纯膜,发现在pH为4或5时形成膜的拉伸强度略微提高,在pH为6或7时形成膜的拉伸强度((13.13±0.78) MPa或(12.99±0.56) MPa)显著提高,断裂伸长率随着pH地增加而降低。紫薯花青素对膜的热稳定性没有显著影响。pH响应指示膜在不同缓冲溶液中表现出了明显的颜色变化。新鲜牛奶在25 oC下储存72 h后,P7膜表现出明显的颜色变化。综上,该膜具有良好的的物理性能和pH值响应性能,在食品保鲜智能包装中有潜在的应用价值。

紫薯低糖凝固型酸乳的研制及花青苷稳定性研究

以漯紫薯4号和生牛乳为主要原料,木糖醇为甜味剂,在配方优化的基础上,研制出具有营养保健功能的凝固型紫薯低糖酸乳。通过单因素试验和正交试验优化,确定了紫薯低糖凝固型酸乳的最佳配方,即生牛乳添加量82%,发酵剂添加量0.8%,紫薯浆添加量8%(紫薯浆料液比2∶3),木糖醇添加量4.5%,发酵温度42℃,发酵时间4 h。在此工艺条件下制得的紫薯低糖凝固型酸乳呈淡紫色,风味独特、营养丰富、花青苷稳定性好,是一款适合大众口味的风味保健酸乳。

紫薯花色苷稳定性及热降解动力学研究

以紫薯花色苷为研究对象,探讨了温度、柠檬酸、抗环血酸、葡萄糖、蔗糖、氯化钠、苯甲酸钠对其稳定性的影响。结果表明,在中性环境下,紫薯花色苷的热降解符合一级反应动力学,活化能为25.36 kJ/mol,花色苷的半衰期随着温度的升高而缩短。柠檬酸、蔗糖、0.1%葡萄糖能提高紫薯花色苷的稳定性,而抗坏血酸、氯化钠和0.5%葡萄糖会加速紫薯花色苷的降解,苯甲酸钠则对紫薯花色苷的稳定性没有明显影响。当蔗糖添加量为0.5%时,可使紫薯花色苷的半衰期延长为原来的2.5倍左右,护色作用最好;其次为柠檬酸添加量0.5%。食品成分非常复杂,在食品加工过程中,需要选择对花色苷破坏性小的添加物来制备紫薯类产品。

紫甘薯花青素类成分研究进展

甘薯是世界十大粮食作物之一,紫甘薯是甘薯的新品种,营养价值高,具有一定的抗氧化、保肝、抗肿瘤等药理活性,已成为近年来食品与药品研究的热点。紫甘薯花青素类成分含量高,提取成本低,具有较高的应用价值。本文综述了近10年来紫甘薯花青素类化学成分及营养价值研究进展,为后续紫甘薯研究提供参考。

超声辅助提取紫薯中花青素的工艺优化研究

目的:以紫薯为材料,优化紫薯花青素的提取工艺。方法:利用超声波辅助提取法以提取时间、液料比、乙醇体积分数、超声功率为考察因素,以花青素的提取量为评价指标,通过单因素实验和正交实验得到最佳提取工艺。结果:在液料比为1∶10(g∶mL)、乙醇体积分数为70%、超声功率为150 W,提取时间为30min时紫薯花青素的提取量最高,为60.8mg/100g。结论:工艺稳定,适用于紫薯花青素的提取。

紫色马铃薯“黑金刚”中花青苷组分和含量分析

采用超高效液相-三重四极杆串联质谱法对我国紫色马铃薯品种"黑金刚"中花青苷进行组分和含量分析。结果表明:紫色马铃薯中主要含有7种花青苷,分别是牵牛花素-3-芸香糖苷-5-葡萄糖苷、芍药素-3-芸香糖苷-5-葡萄糖苷、飞燕草素-3-p-香豆酰-芸香糖苷-5-葡萄糖苷、牵牛花素-3-咖啡酰-芸香糖苷-5-葡萄糖苷、牵牛花素-3-p-香豆酰-芸香糖苷-5-葡萄糖苷、牵牛花素-3-葡萄糖苷、芍药素-3-p-香豆酰-芸香糖苷-5-葡萄糖苷。其中牵牛花素-3-葡萄糖苷在马铃薯中首次发现。牵牛花素-3-p-香豆酰-芸香糖苷-5-葡萄糖苷是紫色马铃薯花青苷的主要组分,占总花青苷含量的64.6%(含量为5.04g/kg干质量),其次是芍药素-3-p-香豆酰-芸香糖苷-5-葡萄糖苷占总花青苷含量的20%(含量为1.56g/kg干质量)。