超滤膜在果汁加工中的应用研究

选用中空纤维PAN膜、羧基化改性的PAN板式膜、PS膜和PS-SPS膜四种国产膜材料对苹果汁进行超滤澄清处理,比较不同膜对苹果汁理化指标的影响以及处理果汁的最佳条件、最佳工艺。     

番茄汁Maillard反应制备烟用香料的研究

研究了番茄汁的Maillard反应条件,对产物的挥发性成分进行了GC/MS分析,共鉴定出32种成分,加料实验表明卷烟的感官质量得到明显改善,口腔感觉舒适干净,增加了甜烤香,且烟香透发性增强。     

生姜6-姜辣素的提取及姜汁去屑洗发水的研制

优选生姜6-姜辣素的提取方法,研究生姜提取液在去屑洗发水中的应用。采用HPLC法,以6-姜辣素为考察指标,分别对榨汁法、加热回流提取法、微波提取法、超声提取法和超声-微波协同萃取法的生姜提取液进行含量测定;通过抑菌实验,考察不同添加量的生姜提取液对洗发香波性能影响,确定生姜提取液的最佳添加量,最小抑菌浓度。结果显示,榨汁法为生姜的最佳提取方法,姜汁的最佳添加量是15%,最小抑菌浓度是:糠秕马拉色菌MIC为18.75 mg/mL,金黄色葡萄球菌、大肠埃希菌和白色念珠菌MIC均为9.375 mg/mL。     

蓝莓汁生产热烫工艺对多酚氧化酶及多酚类化合物的影响

蓝莓是一种含有丰富多酚类化合物的果汁生产原料,具有抗氧化、抗炎等多种生理活性。蓝莓在加工过程中使用的热烫工艺,会在灭酶的同时损伤蓝莓汁抗氧化能力。本文研究了笼屉式加热与堆放式加热两种热处理方式。结果表明,笼屉式热烫处理效果好于堆放式热烫。笼屉式热烫2min可达到灭活多酚氧化酶的效果,同时可保留较多的多酚类抗氧化成分。     

自絮凝颗粒酵母发酵菊芋汁生产乙醇

分别采用分批和连续发酵方式,对自絮凝颗粒酵母Saccharomyces cerevisiae flo发酵菊芋汁生产乙醇的条件进行了优化. 与先酶解菊芋汁后再用自絮凝酵母发酵的分步糖化发酵相比,分批发酵过程中同时加入菊粉酶和自絮凝酵母的同步糖化发酵乙醇得率高,发酵时间短. 当菊芋汁总糖浓度分别为105和179 g/L时,同步糖化发酵的最高乙醇浓度达50和82.5 g/L,比分步糖化发酵高6.4%和13.8%. 在连续发酵过程中应用同步糖化发酵法,当稀释率为0.02 h-1时,乙醇浓度约为90 g/L时达到稳定状态,乙醇得率达到理论值的90%,生产强度达2.12 g/(L×h).     

Anthocyanins remain stable during commercial blackcurrant juice processing

Abstract: It remains important to establish the stability of anthocyanins throughout commercial processing in order to maintain the bioactivity of the processed food/s. The present study aimed to assess the recovery and formation of anthocyanins and their free phenolic acid degradation products during the commercial processing of blackcurrant juice concentrate. A bench‐scale processing model was also established to allow for alteration of predefined parameters to identify where commercial processes could be modified to influence anthocyanin yield. No significant loss in anthocyanins was observed throughout the commercial processing of blackcurrants, from whole berry through milling, to pectin hydrolysis and sodium bisulphite addition (P ≥ 0.7). No significant loss in anthocyanins was observed following the subsequent processing of pressed juice, through pasteurization, decantation, filtration, and concentration (P ≥ 0.9). Similarly, the bench‐scale model showed no significant losses in anthocyanin content except during pasteurization (22%± 0.7%, P < 0.001). In the full‐factorial Design of Experiment model analysis, only sodium bisulphite concentration had an impact on anthocyanin recovery, which resulted in an increase (23% to 27%; P < 0.001) in final anthocyanin concentration. No phenolic degradation products (free protocatechuic acid or gallic acid derived from cyanidin and delphinin species, respectively) were identified in any processed sample when compared to authentic analytical standards, analyzed by ultra‐performance liquid chromatography DAD. Practical Application: This article provides crucial data directly applicable to commercial juice processing, such as improving anthocyanin yield and practical considerations for anthocyanin stability and degradation. This aspect is particularly pertinent considering the current commercial interest in anthocyanin‐derived phenolic acids and their health‐related benefits. Further research and development targets in the area of commercial juice product development are identified.     

天然复合蔬菜汁豆腐的研制

探讨了以番茄汁、黄瓜汁和大豆为原料研制天然、营养的保健豆腐,其制作最佳工艺参数为豆乳浓度１∶８,豆乳、番茄汁比２００∶２６,豆乳、黄瓜汁比２００∶６０,点浆温度８０℃。该产品呈淡绿色,具有黄瓜的清香味和纯正的豆香味,营养更丰富,膳食结构更合理,符合现代食品发展趋势,具有广阔的市场前景     

Naringinase Immobilization in Packaging Films for Reducing Naringin Concentration in Grapefruit Juice

Naringin, a bitter compound in citrus, may be converted to a nonbitter form by enzymic hydrolysis. Our objective was to determine the feasibility of immobilizing naringinase in a food contact approved packaging film. Naringinase from Penicillium sp. was immobilized in cellulose acetate films with up to 23% efficiency at 7°C. Kinetic studies showed that the free enzyme had an optimum pH=3.5 and the immobilized enzyme pH=4.0. Activation energy decreased upon immobilization (from 14.2 to 11.0 Kcal/mol), thus providing an increased catalytic efficiency for immobilized naringinase. The Michaelis constant for immobilized naringinase (K_m=2.1 mM) was lower than for free enzyme (K_mm=3.6 mM). Keeping films under dry storage for 1 mo at room temperature did not cause decreased enzyme activity. A film area/volume ratio (cm²/mL of 10° Brix grapefruit juice) of 7.2 hydrolyzed 60% of the naringin in 15 days at 7°C.     

乳酸发酵番茄汁中间生产试验

将筛选出的保加利亚乳杆菌(L. bulgaricus)和嗜热链球菌(Str. thermophilus)应用于乳酸发酵番茄汁的中试生产中。先在20升发酵罐内进行了两批试验,确立了初步的生产工艺流程,然后在500升发酵罐进行了进一步试验,获得了成功,生产出的乳酸发酵番茄汁pH为4.0～4.3,乳酸含量0.7％左右,加蔗糖3％,不添加防腐剂、香精、色素等化学物质。保存半年后经检测,其理化及微生物学指标均符合国家规定标准。申试结果为工业规模生产奠定了基础。     

姜汁凝乳影响因素的研究

生姜经清洗、打浆榨汁后可制得姜汁,将姜汁以2%的比例添加到经杀菌和冷却处理的鲜乳中可制成具有凝乳状态的姜汁牛乳。为了探讨姜汁凝乳的影响因素,文中研究了温度、pH值、牛乳蛋白质和盐类等对姜汁凝乳的影响。结果表明,温度和pH值是影响姜汁凝乳的关键外部因素。牛乳蛋白质、CaCl2、NaCl是凝乳促进物。