咖啡产品的加工技术研究进展

咖啡是世界范围内最为普遍的饮品之一,咖啡产品在中国市场具有很大的潜力.本文对挂滤咖啡、即饮咖啡、冷萃咖啡以及速溶咖啡粉的加工技术进行总结,从加工成本、影响品质、优缺点等方面着重讨论了速溶咖啡粉干燥技术,旨在为速溶咖啡粉干燥技术的选用以及工业化生产提供借鉴和理论支持.对于未来咖啡产业具有重大意义.     

酶解咖啡鲜果对烘焙咖啡饮用品质和化学成分的影响研究

选用不同种类的酶对云南小粒咖啡去皮鲜果进行酶解,确定胃蛋白酶最适于制备麝香猫咖啡,随后进行了胃蛋白酶酶解咖啡鲜果的条件优化,确定最佳酶解条件为胃蛋白酶添加量1%,酶解2 h,酶解温度55℃,此时感官评分为13.5分,高出未处理咖啡鲜果的感官评价结果 1倍。同时研究酶解对咖啡鲜果中主要化学成分的影响,及其对咖啡鲜果烘焙后饮用品质的作用。     

高温烘干对玉米湿法加工的影响

总结了美国等国采用高温烘干对湿法加工影响的研究历史和现状.实践表明高温烘干高水分的玉米湿磨时存在研磨能力下降、淀粉收率低、淀粉中蛋白含量高、胚芽收率低、胚芽油质量差、纤维脱水困难、蛋白粉烘干困难等一系列问题.为玉米加工厂提供了科学数据,以及合理使用玉米烘干设备的建议.     

不同干燥方式对西番莲果皮中湿法改性膳食纤维品质的影响

本实验以西番莲果皮中湿法改性膳食纤维为原料,探讨了热风干燥、微波干燥、真空冷冻干燥、喷雾干燥和冷冻喷雾干燥五种干燥方式对其色泽形貌、粉体性质及理化性质的影响。结果表明,湿法改性后,纤维组织破坏严重,再经不同干燥方式处理,膳食纤维的形貌和色泽都产生很大变化;真空冷冻干燥和冷冻喷雾干燥处理的膳食纤维表现出极佳的持水力、持油力及吸湿性,结果分别为:持水力24.1、16.4 g/g;持油力11.8、8.3 g/g;吸湿性19.3%、19.8%;真空冷冻干燥和冷冻喷雾干燥振实密度较小,其分散性、溶解性和吸附性能较佳;喷雾干燥处理的膳食纤维休止角为38.5°,表现出最佳的流动性;另外各处理间的膨胀力和阳离子交换能力差异不明显。综上,真空冷冻干燥和冷冻喷雾干燥处理对西番莲果皮中湿法改性膳食纤维品质改善最为显明显。     

复合酶制剂在玉米淀粉湿法加工中的应用

玉米淀粉加工复合酶制剂是玉米淀粉加工专用酶制剂,主要由纤维素酶、木聚糖酶等组成.为了探讨复合酶制剂在玉米淀粉湿法加工过程中的工艺效果,通过复合酶制剂在玉米纤维洗涤过程中的应用,考察经过酶反应处理后玉米粉浆粘度和纤维吸水性的变化,以及淀粉和蛋白质收率、蒸汽消耗量等指标.结果表明,酶制剂能够将玉米的胚乳淀粉细胞壁及种皮纤维...     

基于主成分分析优化咖啡微水脱胶工艺

为优化微水脱胶工艺,本文分析机械脱皮脱胶+晒干（A）、机械脱皮脱胶+烘干（B）、手工脱皮+带胶烘干（C）、机械脱皮脱胶+水洗脱胶+烘干（D）及手工脱皮+水洗脱胶+烘干（E）五种不同加工工艺对咖啡生豆中香味前体物质（蛋白质、粗脂肪）、滋味呈味物质（咖啡因、绿原酸、咖啡酸）及挥发性物质相对含量的影响。结果显示,机械脱皮脱胶+烘干处理组相比于手工脱皮+带胶烘干处理组,随着果胶残留量的增加,咖啡生豆中绿原酸、咖啡酸含量显著增加（P<0.05）,蛋白质含量显著减少（P<0.05）;机械脱皮脱胶+水洗脱胶+烘干处理组相比于机械脱皮脱胶+烘干处理组,咖啡生豆中粗脂肪、咖啡酸含量显著增加（P<0.05）;机械脱皮脱胶+烘干处理组相比于机械脱皮脱胶+晒干处理组,咖啡生豆中绿原酸、咖啡酸含量显著增加（P<0.05）。手工脱皮+带胶烘干、手工脱皮+水洗脱胶+烘干处理后咖啡生豆中蛋白质、粗脂肪、咖啡因含量均较低,机械脱皮脱胶+水洗脱胶+烘干处理后咖啡生豆中蛋白质含量最高,达13.71%,粗脂肪含量仅次机械脱皮脱胶+晒干,为9.84%。按照品质指标综合得分由高到低排名：D>B>...     

干燥方式对湿法加工奶茶固体饮料感官和稳定性的影响

为了考察干燥方式对湿法加工奶茶固体饮料感官和稳定性的影响,本实验以喷雾干燥和真空干燥两种方式干燥奶茶固体饮料。结果表明,经过真空干燥的奶茶粉冲泡浮油严重,口感和组织状态显著差于喷雾干燥奶茶粉。真空干燥奶茶粉表面油含量为13.44%,而喷雾干燥仅为0.78%,通过粒径分布和透光率测定,均显示真空干燥奶茶粉稳定性差,喷雾干燥稳定性较佳。在得率方面,喷雾干燥得率59%,真空干燥74%。综合各项结果,喷雾干燥更适合干燥湿法奶茶固体饮料。     

灰色关联度法评价单宁酶对余甘子原汁品质的影响

通过测定单宁酶脱涩过程中余甘子原汁营养指标及风味值的变化,并对试验数据进行相关性和灰色加权关联度分析,探讨酶解过程中余甘子原汁品质的变化规律。结果表明,最佳酶解条件为：单宁酶浓度0.1%、酶解温度50℃、酶解时间120 min,在该条件下余甘子原汁风味值为5.80、多酚含量为6.09 mg/mL、黄酮含量为27.31 mg/mL、维生素C含量为1.26 mg/mL。因此,在余甘子原汁脱涩过程中,选择合适的酶解条件,对脱除余甘子原汁的涩味、较好地保留余甘子原汁中的营养物质、提高功能价值具有重要作用。     

干燥模式对混合型卷烟感官质量的影响

为了解不同干燥模式对混合型卷烟感官质量的影响,考察了SH6薄板烘丝、HXD气流烘丝和KLD薄板烘丝3种干燥模式对"都宝A"牌号卷烟中白肋烟、香料烟、烤烟3个模块叶丝感官质量的影响,并利用灰色关联度分析方法对混合型卷烟干燥模式的组合进行了优化。结果表明:①"都宝A"牌号卷烟中的白肋烟模块叶丝,用SH6薄板干燥后,烟丝的香气特性最优,浓度、劲头大;用HXD气流干燥后,烟丝的口感特性最优。香料烟模块叶丝,用SH6薄板干燥后,烟丝的香气特性最优;用HXD薄板干燥后,烟丝的口感特性最优。烤烟模块叶丝,用KLD薄板干燥后,烟丝感官综合质量最优。②适合"都宝A"牌号卷烟的最优干燥模式组合为:白肋烟用SH6烘丝,香料烟用SH6烘丝,烤烟用KLD烘丝。     

咖啡杏仁乳的加工工艺及稳定性研究

以苦杏仁、咖啡为主要原料,研制一种复合型保健饮料。采用正交试验的方法确定合理的配方和适宜的工艺条件,并对产品质量作了评价。结果表明:杏仁量为3%、咖啡量为2%,加入6%的糖和0.4%的乳化稳定剂可以保证产品具有最佳的感官品质,同时具有稳定性好和滋味浓厚的特点。选择HLB为9.3为咖啡杏仁乳的最佳HLB值,即单甘酯与蔗糖酯的最佳比例为3∶7。在121℃下杀菌15min,制得的咖啡杏仁乳为咖啡色。35℃条件下进行保温7d,结果表明:咖啡杏仁乳在试验期内无沉淀,无脂肪分层,无变质腐败现象出现。     

Potential of lactic acid bacteria to improve the fermentation and quality of coffee during on‐farm processing

This study describes, for the first time, the potential use of selected lactic acid bacteria (LAB) to conduct improved coffee bean fermentation during on‐farm wet processing. Among different strains tested, Lactobacillus plantarum LPBR01 showed a suitable production of organic acids and flavour‐active esters in a coffee‐pulp simulation medium and was used as starter culture under field conditions. The results indicated that L. plantarum LPBR01 was able to establish an accelerated coffee‐pulp acidification process and potentially reduced the fermentation time from 24 to 12 h. The inoculation of LPBR01 strain also increased significantly the formation of volatile aroma compounds during fermentation process (such as ethyl acetate, ethyl isobutyrate and acetaldehyde) and enabled the production of beverage with distinct sensory notes and a remarkable increase in quality compared to the conventional process. Our results suggest that the use of LAB in coffee processing is an ideal alternative way to conduct faster and improved coffee bean fermentation.     

Aroma recovery from roasted coffee by wet grinding

Aroma recovery as determined by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) was compared in coffees resulting from conventional grinding processes, and from wet grinding with cold and hot water. Freshly roasted coffee as well as old, completely degassed coffee was ground in order to estimate the relationship of internal carbon dioxide pressure in freshly roasted coffee with the aroma loss during grinding. The release of volatile aroma substances during grinding was found to be related to the internal carbon dioxide pressure, and wet grinding with cold water was shown to minimize losses of aroma compounds by trapping them in water. Due to the high solubility of roasted coffee in water, the use of wet-grinding equipment is limited to processes where grinding is followed by an extraction step. Combining grinding and extraction by the use of hot water for wet grinding resulted in considerable losses of aroma compounds because of the prolonged heat impact. Therefore, a more promising two-step process involving cold wet grinding and subsequent hot extraction in a closed system was introduced. The yield of aroma compounds in the resulting coffee was substantially higher compared to conventionally ground coffee.     

真空技术在皮革湿加工中应用的研究

本文介绍了真空技术在皮革湿加工的应用机理及特点，并对皮革真空湿加工的主要影响因素作了分析。     

Influence of the postharvest processing method on polysaccharides and coffee beverages

Fresh coffee fruits were subjected to different types of postharvest processing. Intact fruits were processed using the dry method (DI), peeled fruits were processed using the semi‐dry method (DP) and fruits were processed using the wet method (W). The extraction of polysaccharides from the seeds from the unprocessed and processed fruits indicated that arabinogalactans and (galacto)mannans were the main polysaccharides. Higher amounts of polysaccharides were extracted from processed coffee. Among the treatments, lower amounts of water‐soluble galactomannans were obtained from coffee beans processed by the dry and wet methods. The polysaccharides obtained from beverages prepared using beans from DI, DP and W methods showed different yields, total sugar and protein contents. Galactomannans and AGPs were also present in the coffee beverages. Although differences were found in the chemical compositions, no differences were observed in the viscosity or surface tension of coffee beverages from the DI, DP and W methods.     

超声波及其在湿处理中的应用

综述了超声波及其在纺织品湿加工中的应用.在纺织加工的不同阶段,超声波在染色方面的应用是最有发展前景的.当然,在其他领域的应用也是有益的.通常高能量的超声波提高了织物湿处理的速度.在使用超声波的加工过程中可以节约一定的时间、能量和化学品.此外,在许多染色过程中可以减少污水的产生.然而,至今还没有由超声波辅助的大规模工业生产设备.     

Influence of coffee/water ratio on the final quality of espresso coffee

Espresso coffee is a polyphasic beverage in which the physico‐chemical and sensory characteristics obviously depend on both the selection of ground roasted coffee and the technical conditions of the percolation process. The aim of this work was to evaluate the influence of the coffee/water ratio on the physico‐chemical and sensory quality of espresso coffee. Furthermore, the influence of botanical varieties (Arabica and Robusta) and the type of roast (conventional and torrefacto) on the selection of coffee/water ratio was studied. The relationship between pH and the perception of acidity intensity is discussed in relation to the influence of the coffee/water ratio, type of coffee and roast. The optimisation of other technical parameters in previous studies seemed to minimise the influence of an increase in the coffee/water ratio on the extraction of soluble and solid compounds. In fact, only some sensory attributes, such as bitterness, astringency and burnt, acrid and earthy/musty flavours were proposed as relevant to the selection of 6.5 g 40 mL^?1 or 7.5 g 40 mL^?1 in conventional roasted coffees (Arabica 100% and Robusta blend), and 6.5 g 40 mL^?1 in torrefacto roasted coffees. On the other hand, the addition of sugar during the roasting process in torrefacto roast coffees seemed to contribute to a higher generation of acids, melanoidins and other compounds by the Maillard reaction or caramelisation, which led us to select the lowest coffee/water ratio. Copyright © 2006 Society of Chemical Industry     

Microbial ecology and starter culture technology in coffee processing

Coffee has been for decades the most commercialized food product and most widely consumed beverage in the world, with over 600 billion cups served per year. Before coffee cherries can be traded and processed into a final industrial product, they have to undergo postharvest processing on farms, which have a direct impact on the cost and quality of a coffee. Three different methods can be used for transforming the coffee cherries into beans, known as wet, dry, and semi-dry methods. In all these processing methods, a spontaneous fermentation is carried out in order to eliminate any mucilage still stuck to the beans and helps improve beverage flavor by microbial metabolites. The microorganisms responsible for the fermentation (e.g., yeasts and lactic acid bacteria) can play a number of roles, such as degradation of mucilage (pectinolytic activity), inhibition of mycotoxin-producing fungi growth, and production of flavor-active components. The use of starter cultures (mainly yeast strains) has emerged in recent years as a promising alternative to control the fermentation process and to promote quality development of coffee product. However, scarce information is still available about the effects of controlled starter cultures in coffee fermentation performance and bean quality, making it impossible to use this technology in actual field conditions. A broader knowledge about the ecology, biochemistry, and molecular biology could facilitate the understanding and application of starter cultures for coffee fermentation process. This review provides a comprehensive coverage of these issues, while pointing out new directions for exploiting starter cultures in coffee processing.     

精制直条米线湿法生产工艺的研究

以精白大米为原料,经磨浆、脱水、搅拌捣碎、挤粿、蒸胚、榨条、时效Ⅰ、复蒸、时效Ⅱ、梳条等现代湿法工艺连续生产直条米线,其产品质量和工艺指标均超过传统工艺产品,为传统湿法生产工艺的技术改造和实现大规模工业生产创造了条件。     

咖啡豆的化学组分差异与感官品质的相关性分析

为了探讨咖啡中化学组分与感官品质之间的关系,通过测定7种不同产区咖啡豆的蛋白质、还原糖、绿原酸、葫芦巴碱和咖啡因含量以及咖啡液pH,分析这些组分含量的多少与感官品质之间的关系。经Pearson线性相关性检验,咖啡感官评分高低与咖啡因含量和葫芦巴碱含量的线性相关性具有显著性,均成负相关,相关系数分别为r=0.855和r=0.366。同时咖啡感官好的风味品质与咖啡因损失量(r=0.897)、葫芦巴碱损失量(r=0.848)、绿原酸损失量(r=0.933)、还原糖损失量(r=0.713)正相关性均为极显著,与蛋白质损失量的线性相关性不显著。另外,7种不同产区咖啡豆,不同烘焙程度和不同品种咖啡间pH的差异不大。