微波辅助提取杨梅色素及抗氧化作用研究

利用响应面分析法(Response surface Method)对杨梅色素微波辅助提取工艺进行优化,并与普通提取法进行比较.在单因素试验的基础上,根据中心组合(Box-Benhnken)实验设计原理,采用四因素三水平的响应面分析法,以色素含量为响应值进行回归分析.结果表明微波辅助提取杨梅色素的最佳工艺条件为:料液比1:4,提取时间16 min,提取功率447 W,提取温度63℃,杨梅色素平均含量为145.07μg/mL,与模型预测值基本相符.相比普通提取法,微波辅助提取法是一种较好的杨梅色素提取方法.另外,杨梅色素具有较强的抗氧化作用.     

天然杨梅混合果汁饮料的研制

本试验应用正交试验设计,以浙江主栽荸荠种杨梅(Myrica rubra)果汁为主,分别与一定比例的富含独特果香的宝交早生草毒、红香蕉葡萄及红心李汁进行调配．通过感官评定,并结合理化分析及微生物检验,从中筛选出若干个色香味佳的天然(不添加任何合成色素和香精)杨梅混合果汁饮料最优配方．     

响应面法优化杨梅核仁油浸提工艺及其脂肪酸组成分析

在单因素试验基础上,采用响应面分析法对木洞杨梅核仁油浸提条件进行优化,分析了浸提时间、料液比及浸提温度等3个因素对杨梅核仁得油率的影响;并采用气相色谱法对杨梅核仁油的脂肪酸组成进行分析。根据单因素试验及响应面分析得出最佳浸提工艺条件为浸提时间2 h 20 min、料液比1∶7.5(m/V)、浸提温度48.5℃,此条件下的杨梅核仁油得油率高达62.52%,即提取率为93.31%。脂肪酸组成分析结果表明:木洞杨梅核仁油富含不饱和脂肪酸,高达86.49%,其中油酸的质量分数达47.9%,亚油酸质量分数达到37.3%,且含有少量亚麻酸(0.12%)、花生一烯酸(0.29%)、棕榈一烯酸(0.88%),具有较高的营养价值。     

杨梅果汁饮料的澄清试验

本试验以瑞安黑碳杨梅(即黑碳梅)为主要原料,制成杨梅果汁饮料。对杨梅果汁饮料的澄清试验做了酶解条件的研究和澄清剂的选择。考察了酶解温度、酶解液初始pH值、酶解时间和酶用量对杨梅果汁可溶性固形物的影响;确定了酶解的最优条件为:酶解温度为50℃,酶解液初始pH=3.8-4.2,酶解时间为2h,酶量为4g／L杨梅果汁;研究了明胶、单宁及二种混合澄清剂对杨梅果汁饮料的澄清效果。结果发现,在杨梅果汁中添加明胶0.012％和单宁0.008％,室温静置6h后,即可得到透光率88％以上,清澈透明且对热稳定的杨梅果汁饮料。     

杨梅黄酮类化合物提取条件优化研究

为综合开发杨梅资源,对杨梅鲜果中黄酮的最佳提取工艺进行了探讨。以乙醇作为提取剂,通过二次回归旋转组合设计试验,确定杨梅黄酮提取的最佳工艺参数。结果表明,杨梅黄酮的最佳提取工艺为提取温度46℃,液料比(v/w)11:1,乙醇浓度70%,pH3,提取次数1次。在此条件下,杨梅黄酮的提取率为93.72%。该研究为杨梅的深度开发及新型保健资源的研究提供一定的理论依据。     

杨梅果汁、果酒和果醋芳香成分初步分析

采用气相色谱-质谱法对比分析了杨梅果汁、果酒和果醋的主要芳香物质成分.结果表明,杨梅果汁芳香成分以萜烯类成分(45.91％)为主,果酒芳香物质以醇类(43.18％)和酯类(39.79％)为主,而果醋芳香物质则以醇类(40.81％)、酯类(19.10％)和酸类等成分(19.39％)为主.与汁、酒比较,杨梅果醋芳香成分分布最为丰富,而且β-苯乙醇是杨梅果酒和果醋共有的含量最大的芳香成分.杨梅果汁特征芳香成分石竹烯在酒精和醋酸发酵过程中极易损失,会影响原果风味,在生产实践中需加以关注.     

杨梅果实抗氧化物质的提取及其稳定性研究

以乙醇为介质,杨梅果实中抗氧化物质提取量(trolox物质的量)为指标,进行响应面(RSM)分析,优化超声提取杨梅果实中抗氧化物质的浸提工艺。以超声时间、温度、料液比、乙醇体积分数为影响因子,在单因素试验的基础上,选取3个主要影响因素,进行3水平中心组合试验设计。试验结果表明,在考察范围内酒精体积分数对杨梅果实中抗氧化物质提取的影响最为显著,超声提取的最佳工艺条件为:超声时间54.94 min、料液比1∶39.38(m∶V)、乙醇体积分数66.72%,在该条件下杨梅果实中抗氧化物质提取率达460.66μg/g(trolox物质的量)。杨梅果实抗氧化物的稳定性研究表明,在贮存过程中应注意避免接触金属材料和光照,其在酸性条件下(pH3)较稳定。杨梅果实的色泽L*值、b*值与其抗氧化物质含量呈显著负相关;a*值与其抗氧化物质含量无显著相关性;花色苷、多酚含量与其抗氧化物质物质的量呈极显著的正相关。     

杨梅果汁花色苷及其色泽稳定性的研究

本文就氧、维生素C(Vc)、包装材料、贮藏温度以及光等因素对杨梅汁花色苷及其色泽稳定性的影响作了探讨。结果表明:杨梅汁花色苷的降解遵循一级反应动力学规律(r<0.98)。氧及Vc均不利于花色苷及色泽保存。复合铝箔袋装杨梅汁其花色苷和色泽稳定性很高,涂料罐则又不宜装杨梅汁。低温(4℃)贮藏八个月的杨梅汁花色苷及其色泽变化甚微,高温(37℃)贮藏对花色苷和色泽破坏严重,一个月内杨梅汁即失去原有紫红色而呈褐色,且瓶底有大量褐色降解物。曝光贮藏会促进杨梅汁花色苷降解和色泽的变化。     

高效液相法测定杨梅苷脂质体的药物含量及包封率

本文建立了杨梅苷脂质体中药物含量及包封率测定的高效液相新方法.该方法使用C18色谱柱(150mm×4.6mm,5μm);流动相为甲醇-磷酸盐缓冲溶液(40:60);流速为0.4 mL/min;柱温为室温;紫外检测波长为367nm.采用冷冻离心法分离杨梅昔脂质体中的游离药物.结果表明在本色谱条件下杨梅苷与卵磷脂、溶剂峰能有效分离,杨梅苷在0.8～40 μg/mL(r=0.9999,n=5)具有良好的线性关系,回收率100.9%～101.9%,日内RSD及日间RSD均<2%(n=5).该方法准确可靠、简单易行,可以用于杨梅苷脂质体含量及包封率的测定.     

杨梅果酒的海藻酸铝固定化发酵研究

杨梅果汁可以用来发酵成杨梅干红果酒,传统的游离发酵杨梅果酒的方式存在着许多不足.为此,本文通过与游离发酵方式进行对比,探讨了海藻酸铝固定化酵母细胞发酵杨梅果酒的方式,并对比了两种发酵方式生产出的杨梅新酒的色泽稳定性.结果表明,杨梅果酒的海藻酸铝固定化酵母细胞发酵最佳工艺参数是发酵温度20℃、海藻酸钠浓度3%(w/v)、氯化钙浓度3%(w/v)、硫酸铝浓度2%(w,v);采用此方法有许多优点,包括珠子可以重复使用、发酵速度比游离发酵方式的更快以及可以得到更好品质的杨梅干红果酒,特别是在花色苷稳定性方面.另外,结果还表明,固定化发酵的杨梅果酒在酒精度、pH值以及总酸方面同游离发酵没有显著差别,但可获得比游离发酵更低的果酒残糖和更高的果酒澄清度.因此,这种固定化发酵方式更适用于杨梅干红果酒的生产.     

金刺梨原汁脱涩及其与梨-南瓜复配果蔬汁的研制

目的:解决金刺梨原汁口感酸涩,开发口感良好、酸甜适口且稳定性高的金刺梨复配果蔬汁。方法:首先采用明胶吸附或β-环糊精包埋法进行原汁脱涩处理,其次拟采用鲜榨梨汁和南瓜浆进行复配,并进行巴氏杀菌条件优化。结果:加入0.5%明胶可使金刺梨原汁中单宁脱除率达到63.00%。根据感官评价结果和基本理化指标,确定复配果蔬汁的优化配比为金刺梨汁:梨汁:南瓜浆体积比为34:40:26;在85 ℃下处理3 min能够使复配汁中细菌总数降至1.38 lg CFU/mL,酵母和霉菌未检出（<1 CFU/mL）;其可溶性固形物含量、总酸含量分别下降了2.33%和5.98%,超氧化物歧化酶（SOD）保存率为67.8%,还原型维生素C（V_C）和总V_C的保留率分别为78.72%和80.30%;但热处理后复配果汁发生了一定程度褐变。结论:通过对金刺梨原汁进行脱涩及果蔬汁复配得到酸甜适度的金刺梨复配果蔬汁,可为金刺梨的深加工提供技术参考。     

QUALITY AND STABILITY OF BLUEBERRY JUICE BLENDED WITH APPLE,GRAPE AND CRANBERRY JUICE1

Sensory quality and storage stability of blueberry juice blends were investigated with the goal of maintaining dominant blueberry flavor, aroma and color. Apple juice, Concord and Venus grape juices and cranberry juice cocktail were blended at 75, 50 and 25% with blueberry juice. As the percent of blueberry juice decreased, the intensity of blueberry‐related sensory attributes decreased. The 25% Concord and Venus blends were the only blends that resulted in blueberry flavor similar to the reference. Apple and cranberry juice cocktail blended with blueberry juice produced several blends with good flavor and aroma, but they were not readily characterized as blueberry juice. All blends at the 25% level produced blueberry color equal to or greater than the reference. The juice samples were evaluated initially and after three months of storage at 37C. After storage, all blends had decreased red color.     

红豆大枣枸杞复合酸乳的研制

以红豆、红枣、枸杞和牛乳为主要原料,采用保加利亚乳杆菌和嗜热链球菌进行发酵,研制红豆大枣枸杞复合酸乳。以酸乳感官评分为指标,通过单因素实验和正交试验确定了最佳配方。结果表明,混合汁(红枣汁∶红豆浆∶枸杞汁=2∶5∶3)8%、接种量3%、蔗糖7%、复合稳定剂(CMC-Na∶黄原胶=5∶5),0.30%,即制得营养丰富,富有混合汁风味的酸奶。     

Studies on the development of beverages using fruit juice/pulp, separated milk and reconstituted skim milk

Studies were carried out on the development of beverages using fruit juice/pulp, separated milk and reconstituted skim milk. Beverages were prepared by blending juice/pulp from apples, bananas, guavas, litchis and mangos at four different concentrations (100, 200, 300 and 400 g/L) with separated and reconstituted skim milk. Organoleptic evaluation of the beverages showed that apple juice and guava pulp could be blended at up to 300 and 100 g/L in milk products, respectively. Banana and mango pulp could also successfully be used at up to 200 g/L in separated milk and reconstituted skim milk. Litchi juice could be blended up to 300 g/L in separated milk and 200 g/L in reconstituted skim milk.     

新型乌龙茶酸奶的研制

以乌龙茶为原料研制出新型乌龙茶酸奶。通过对乌龙茶汁提取方法及发酵工艺的研究,最终确定乌龙茶汁提取的最佳工艺参数为:冲泡温度90℃、冲泡时间20min、茶水比1∶10;乌龙茶酸奶的最佳配方为:乌龙茶汁3%、接种量2%、蔗糖6%、稳定剂0.05%。制成的乌龙茶酸奶色泽乳白微黄,乌龙茶香与酸奶香味融合较好,风味最佳。     

Unsuitability of data acquired from blended samples for testing orange juice purity

Non-blended juices (83) obtained directly from Spanish oranges and several computer-simulated blends of these juices were used as reference samples for the detection of orange juice dilution. Amino acids (16), absorbances at different wavelengths (3), minerals (3), ash and isocitric acid were determined in each non-blended juice. The values of these characteristics in blended samples were calculated from the proportions of juices used in simulating each blend. When using non-blended juices for reference, no significant erroneous rejection (less than 1% working at the 99% confidence level) of pure juices and quite good detection of diluted samples were observed. By contrast, the use of reference sets of blended samples led to the erroneous rejection of many pure juices (74% of non-blended juices when the reference set was constituted by binary blends).     

Improving Blended Carrot-Orange Juice Quality by the Addition of Cyclodextrins During Enzymatic Clarification

The purpose of this study was to evaluate the effect of cyclodextrins (CDs) on carotene content and quality of blended carrot-orange juice after enzymatic clarification. The blended carrot-orange juice was treated with 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) and gamma cyclodextrin (γ-CD) in different concentrations (1–5 g/100 mL of juice) prior to enzymatic clarification. The results showed that in non-homogenized juice added with HP-β-CD, juice acidity was generally increased from 0.83 to 1.05 g/100 mL. In the homogenized juice added with 3% (w/v) HP-β-CD, the carotene content was also increased to 5.34 mg/mL, meaning two to six times compared to control samples. However, the addition of HP-β-CD prior to juice enzymatic clarification decreased the juice clarity more than that added with γ-CD; both CDs showed wider effect on the ascorbic acid content in non-homogenized than in homogenized, when compared to control samples. The non-enzymatic browning was significantly enhanced by the addition of CDs; though, the total polyphenol content increased with the addition of HP-β-CD from 32.59 to 37.09 and from 29.20 to 35.44 mg GAE/mL in non-homogenized and homogenized juice, respectively. The juice color turned red-yellow with increase in the carotene content of the juice. In conclusion, the addition of HP-β-CD in homogenized juice improved the nutritional and some physico-chemical parameters of the juice.     

芦荟葡萄汁复合饮料工艺研究

以库拉索芦荟、浓缩葡萄汁为主要原料,以柠檬酸、蔗糖等为辅料,芦荟葡萄汁复合饮料生产工艺及配方进行了研究,通过正交试验确定出该饮料的最佳配方组合为A3B3C1D2,即芦荟汁140mL,葡萄汁60mL,柠檬酸0.2%,蔗糖5%。     

Color Stability of Apple and Pear Juices Blended with Fruit Juices Containing Anthocyanins

Apple and pear juices blended with anthocyanin pigmented juices developed haze and color stability during commercial marketing. To determine factors contributing to these problems, juice from apple and d'Anjou pear (prepared from whole fruit) and‘Bartlett’pear (peels and cores) were blended with 5, 10, 20%‘Concord’grape,‘Bing’cherry, or red or black raspberry juice. During storage at 25°C for up to 48 wk, turbidity, polymeric color, and % color due to tannin increased, while anthocyanin concentration decreased. As % anthocyanin pigmented juice increased, turbidity and polymeric color increased and % color due to tannin decreased. Within a given base juice, turbidity was highly correlated with polymeric color (r = 0.78 to 0.97).     

GRAPE JUICE AS AN EXTENDER AND SWEETENER FOR BLUEBERRY DRINKS1

Blueberry juice has a strong flavor and low sugar content, but does not make an affordable, palatable drink unless mixed with water or another juice. This study investigated characteristics of blueberry juice blended with Concord, Reliance, Sunbelt, and Venus grape juices, and Thompson Seedless concentrate (TSC), The blends were evaluated by a trained sensory panel for the attributes of blueberry flavor, color, and aroma, and for astringency, body, and sweetness. Intensity of blueberry-related sensory attributes increased with increased concentration of blueberry juice for all two-way juice beverage blends. Blends sweetened with high fructose corn syrup (HFCS) as opposed to TSC were perceived as significantly different in triangle testing. In three-way blends of blueberry, Concord, and water, replacing HFCS with TSC as a sweetener, and increasing the percentage of blueberry and Concord juice increased intensity ratings for blueberry aroma, and the effects were additive. For the attributes of body, color, flavor, and sweetness, changing sweeteners had no effect, but increasing the percentage of blueberry and Concord grape juice increased the intensity ratings for these characteristics.