2种槟榔干果风味品质的比较

为分析青果、烟果2 种槟榔风味品质差异的形成原因,以槟榔青果和烟果为研究对象,鲜果为对照,测定其可溶性糖及可滴定酸等滋味物质含量,并结合顶空-固相微萃取-气相色谱-质谱联用技术,对其挥发性成分进行提取、鉴定及分析。结果表明,槟榔青果和烟果中可滴定酸等滋味物质及醛类、酚类等挥发性成分差异明显,从而影响二者风味品质。青果可滴定酸含量显著低于烟果,而二者可溶性糖含量之间无显著性差异,导致青果糖酸比显著高于烟果（P＜0.05）。青果、烟果和鲜果中分别鉴定出挥发性成分37、46 种和29 种。其中,青果的主要挥发性成分为醛类、酚类和烃类,相对含量分别为10.81%、9.71%和2.84%,另含少量醚类、醇类、酮类、酯类、萘类,与鲜果的主要挥发性成分相似。烟果的主要挥发性成分为酚类,相对含量达70.86%,远高于酮类、醛类、烃类、醇类、酯类等其他挥发性成分,具有典型的烟熏风味特征。另外,通过主成分分析,可将可滴定酸等11 类风味成分对槟榔整体风味品质的影响分为4 种,且在该主成分评价模型下青果、烟果的风味品质差异明显。因此,以青果和烟果为原料,加工而成的青果槟榔和烟果槟榔风味品质差异明显。     

实时直接分析-四极杆飞行时间质谱法快速分析青果槟榔和烟果槟榔代谢物差异

目的 基于实时直接分析-四极杆飞行时间质谱(direct analysis in real time -quadrupole time-of-flight mass spectrometry, DART-QTOF-MS)技术结合非靶向代谢组学,快速实现青果槟榔与烟果槟榔代谢物差异分析。方法 通过单因素实验,考察影响DART离子源电离效率的关键因素;结合Q-TOF MS以TOF MS和信息依赖采集模式分别在正离子和负离子模式下获得质谱数据,采用多元统计学软件建立有监督和无监督的判别模型并筛选差异化合物。采用MarkerView 1.3.1、PeakView软件及在线数据库对差异化合物进行初步鉴定。结果 在正负两种扫描模式下,DART离子源的最佳工作条件为：离子化温度500℃,样品传输速度0.2 mm/s。在此条件下发现两种食用槟榔化学成分存在差异,获得了25种差异化合物;烟果槟榔中有20种化合物的相对含量高于青果槟榔,有5种化合物的相对含量低于青果槟榔。结论 该研究从代谢组学角度初步揭示了青果槟榔与烟果槟榔代谢物的差异性,可为食用槟榔的加工工艺研究及品质提升提供参考依据。同时,本研究采用实时直接分析质谱技术,具有操作方便、分析速度快、准确度高和稳定性好的优点。     

橡木制品对白兰地中酚类物质的影响

橡木中的酚类物质赋予白兰地独特的风格。通过对不同橡木来源、不同加工工艺、不同添加量、不同陈酿时间等方面的研究，比较不同橡木制品对白兰地中酚类物质的影响。结果表明，同种植物源和地理源的橡木，不同加工工艺生产的橡木片对原白兰地中酚类物质含量的影响相差很大，甚至超过橡木种类的影响；橡木板浸泡原白兰地前期对酚类物质的浸提速度最快；中度烘烤橡木片陈酿的白兰地中酚类物质萃取量最多；当浸提的酚类物质总量相同时，芳香醛占多酚类物质的比例，橡木片〉橡木板〉橡木桶。     

枇杷酚类物质及其生物活性研究进展

枇杷富含酚类物质,目前已鉴定酚酸(羟基肉桂酸和羟基苯甲酸)和黄酮类(黄酮醇、黄烷酮、黄烷醇和黄酮木脂素)等物质50余种。不同组织、品种、发育阶段和采后处理方法均能影响酚类物质组成和含量。枇杷酚类物质有抗氧化、消炎、抗糖尿病、细胞保护、抑菌等生物活性。本文对枇杷酚类物质组成、含量分布和生物活性进行综述。     

不同槟榔果常规营养成分和槟榔碱含量分析

对海南产的新鲜槟榔、槟榔烟果、槟榔籽3种样品作槟榔碱含量和常规营养成分分析.结果显示:不同样品中各槟榔碱及营养成分存在一定差异,槟榔碱在0～12.5 mg/L范围内呈线性关系,线性回归方程为Y=0.025 2x+0.063 2,测得新鲜槟榔、槟榔烟果、槟榔籽的槟榔碱含量分别是0.422%、0.184%、0.329%;新鲜槟榔:蛋白质6.23%,粗脂肪17.52%,粗纤维17.87%,灰分4.09%,Vc 13.29 ms/g,还原糖13.35%,水分21.32%;槟榔烟果:蛋白质12.05%,粗脂肪13.23%,粗纤维23.31%.灰分4.67%,Vc> 2.64 mg/g,还原糖2.86%,水分7.65%;槟榔籽:蛋白质22.78%,粗脂肪26.52%,粗纤维2.45%,灰分3.94%,Vc> 7.68 mg/g,还原糖17.19%,水分12.56%.未加工的槟榔、加工后的槟榔及槟榔的不同部位的槟榔碱含量和常规营养成分含量存在一定差异.     

液态绿茶酒发酵过程中酚类物质的含量变化及发酵影响因素分析

以信阳毛尖绿茶为主要原料生产液态发酵型茶酒,研究发酵过程中酚类物质的含量变化,并通过单因素实验对酚类物质在不同的发酵温度、蔗糖添加量、SO2添加量及pH条件下的保存率进行了比较与分析。结果表明,发酵温度对酚类物质含量的影响较明显,呈负相关;蔗糖添加量较高时酚类物质含量下降;pH<4时酚类物质含量较低;茶酒发酵可以适当降低SO2的使用量。正交优化实验结果表明,酚类物质在一定含量范围内,茶酒的感官质量较好,是影响其感官质量的重要因素之一。茶酒中总酚含量和感官评分值间并不存在正相关性。     

槟榔果实生长、加工及产品货架期槟榔碱漂移规律研究

采用乙醇超声波-分光光度法对槟榔生长和槟榔加工过程及食用槟榔产品货架期内槟榔碱含量变化进行分析测定。研究结果表明:槟榔从幼果到成熟期槟榔碱含量不断增加,加工和货架期槟榔碱不断流失。鲜槟榔果中槟榔碱含量最高达到0.254 mg/g,加工食用槟榔产品槟榔碱降到0.097 mg/g,货架期内槟榔碱降到0.052 mg/g。     

酚类对酒的风味影响及白酒酚类控制策略

酚类物质是存在于大部分酒中的风味物质,对酒风味品质控制具有重要意义。酒体中的酚类物质组成及含量存在很大区别,本文对酒中酚类物质的来源、含量、化学组成对酒品质的影响及控制策略进行综述,为研究白酒酚类差异的产生原因及控制方法提供思路。     

河南烤烟(40级)酚类物质含量及规律性研究

为研究酚类物质对烟叶品质的影响,测定了河南烤烟（４０级）各等级烟叶的酚类物质含量。结果表明：各等级烟叶的酚类物质含量集中在２．０％～３．０％之间。不同部位的烟叶以上部叶酚类物质含量最高,中部叶次之,下部叶最低。部位相同时,烟叶颜色越深,酚类物质含量越低。此外,酚类物质含量还与烟叶成熟度、叶片厚度等有关系。     

槟榔烘制工艺中不安全因子分析

对传统工艺烘制的槟榔干果、改良烤炉烘烤槟榔干及食用槟榔片产品中存在的不安全因子进行分析。结果显示:苯并芘是影响槟榔产品食品安全的主要因子,烘制方式对槟榔干果中苯并芘含量影响极大,传统黑果烤炉、传统青果烤炉烘制的槟榔干果中苯并芘含量严重超标,但不管哪种烘制方式的制成品中苯并芘含量均未超标;在槟榔产品还可以检出二氧化硫和亚硝酸盐,其含量均在中国相关控制标准内,还不足以引起食品安全问题。     

CHEMICAL AND ANTIOXIDANT PROPERTIES OF CULTIVATED AND WILD FRAGARIA AND RUBUS BERRIES

ABSTRACT

Content of individual sugars, organic acids, total phenolics (TPH), some important phenolic compounds (kaempferol, myricetin, quercetin, and ellagic acid) and total antioxidant capacity (TAC) in the fruits of strawberry, raspberry and blackberry were studied. A comparison was made between cultivars and wild relatives of each species (Fragaria vesca L., Rubus idaeus L. and Rubus fruticosus L.). The main sugars found were fructose and glucose both in the fruits of wild species and the studied cultivars. Citric acid was determined to be the major organic acid in most of tested berries with the exception of blackberry cultivars, where malic acid was dominant. The content of individual phenolic compounds varied among the wild species, as well as among the studied cultivars. Ellagic acid content was higher in F. vesca, R. idaeus and R. fruticosus (122.5 µg/g FW, 12.71 µg/g FW and 61.7 µg/g FW, respectively) than that obtained in analyzed cultivars. Overall, TPH expressed higher values in the wild strawberry and blackberry species in comparison to the studied cultivars, and consequently, the highest levels of TAC were recorded in F. vesca (5.78 mg asc/g FW), followed by R. fruticosus (4.95 mg asc/g FW).

PRACTICAL APPLICATIONS

In recent years, both wild and cultivated berries have become very attractive for consumers because of potentially beneficial phytochemicals contained in these fruits. Fruit nutritional quality can be described by standard quality parameters (sugars and organic acids), and the analysis of antioxidant capacity influenced by specific related compounds. The importance of flavonoids and other phenolics have been suggested to play a preventive role in the development of cancer and heart disease. A significant positive correlation observed in this study between total phenolics and total antioxidant capacity indicate the need for the use of wild species in the breeding programs of small fruits, especially strawberry and blackberry, in order to increase their nutritive value and the health benefits.     

姜与人体营养健康

对姜的营养、保健功能及其在日常生活中的应用进行了介绍，更利于推动我国调味品业的进一步研究与开发。     

新合纤及其制造加工技术

说明了日本新合纤(新聚酯)的发展阶段,介绍了国外(日本西欧和美国)新合纤的市场情况,指出了日本在新合纤领域目前处于世界最先进水平。概括了新合纤制造加工技术及1990～1992年间日本各合成纤维厂商推出的新合纤产品。最后指出了新合纤存在的某些缺点。     

BARLEY AND MALT TANNINOGENS AND BEER QUALITY

Anthocyanogen and catechin contents (tanninogen values) were determined for ten two-row and thirteen six-row barleys and for their corresponding malts. Four barley-malts were then selected for brewing, one with high, one with low, and two with intermediate tanninogen contents. The brews were made using bottom-fermenting (lager) as well as top-fermenting (ale) yeasts, both at 50–55° F. and at 68° F. The quality of the beers, as expressed by standard analyses and flavour evaluation, is discussed in the light of the tanninogen contents of the barleys and the different brewing parameters (yeast type and fermentation temperature).     

Tencel机织物的染整加工及所用染化料

Ｔｅｎｃｅｌ纤维易于原纤化和很高的横向膨润性对染整加工设备选型、工序安排、染化料选用提出了很高的要求，关键的助剂是润滑剂、纤维素酶、柔软剂、树脂整理剂、防原纤化助剂，于是详细讨论了Ｔｅｎｃｅｌ机织物的前处理、初级原纤化、酶处理、染色、二次原纤化和柔性、树脂整理及染化料的应用。     

INSTRUMENTAL AND SENSORY TEXTURE ASSESSMENT AND FRACTURE MECHANISMS OF CHEDDAR AND CHESHIRE CHEESES

Textural attributes of Cheddar and Cheshire cheeses, falling within narrow compositional ranges, were assessed by sensory panels, and from force-compression curves generated by compression between two plates, and, for Cheddar cheese only, by penetrometry. Individual sensory measurements did not relate well to any instrumental one, and were better at discriminating between cheeses. Samples of each cheese variety were fractured in different ways and the fracture surfaces were examined in a scanning electron microscope. Fracture surfaces were formed by cutting directly through the matrix, tearing of the matrix along planes high in fat or cracking at grain boundaries. It is suggested that consideration of fracture mechanism may aid the selection and development of useful instrumental methods for texture assessment of cheese.     

AREA- AND PERIMETER-DEPENDENT PROPERTIES AND FAILURE OF MATURE-GREEN AND RED-RIPE TOMATO PERICARP TISSUE

The influence of tomato fruit ripeness on area- and perimeter-dependent properties and dominant failure mechanisms of pericarp tissue were investigated. Tissue discs from mature-green and red-ripe fruit were punctured with a flat-ended cylindrical probe and compressed with a flat plate at a constant rate of deformation. Approximately linear force-deformation curves were obtained to tissue failure by both puncture and flat plate compression, interrupted by a region of pseudoplastic deformation at a relatively low initial bioyield force. Based on estimated area- and perimeter-dependent coefficients and firmness (force/deformation) values, initial bioyielding of tissue appeared to be associated with an abrupt increase in cell-to-cell compaction. Puncture of mature-green tissue led to premature failure induced by shearing or rupture of tissue at the probe perimeter. The contribution to puncture of perimeter-dependent or shear-associated forces and a putative "zone of influence" increased markedly with ripening, while the contribution of area-dependent or compression associated forces generally decreased. A concomitant decrease in failure force and firmness with ripening reflected a general loss of both tissue compression and shear strengths. These results suggested that the dominant mode of tissue failure changed with ripening, from cell relaxation and rupture to cell debonding. The data obtained in this study emphasize the need to exercise caution in the interpretation of force-deformation parameters derived from puncture tests alone.     

EFFECTS OF TYPES AND LEVELS OF FAT AND RATES AND TEMPERATURES OF COMMINUTION ON THE PROCESSING AND CHARACTERISTICS OF FRANKFURTERS

ABSTRACT— Frankfurter emulsions containing either 25% or 35% beef fat, pork fat, or cottonseed oil were prepared by comminuting at 1500, 2500, or 5000 rpm to temperatures ranging from 45°–85°F. Data were obtained on the viscosities of the emulsions; except for initially high viscosities for which unmelted fat was responsible, the viscosities of emulsions containing the fats, or oil, were similar: viscosities tended to decrease with increasing time and temperature of chopping. The frankfurters were stuffed, smoked, and cooked, and data were obtained on shrinkage, fat retention, ease of peeling, specific gravity, and texture. Shrinkage was inversely related to content of fat. Fat separation mainly occurred in processing frankfurters containing beef fat; the data suggest that emulsions containing beef fat should be comminuted to 65°–75°F to avoid possible under or overchopping: the results show that optimum conditions were time as well as temperature dependent. The air content of frankfurters varied inversely with the maximum temperature attained during communition. Frankfurter skin strength was lessened on increasing the temperatures to which emulsions were communited; elasticity, the equivalent of rubberiness, decreased under these conditions.