新老制曲车间空气中微生物差异初探

以泸州老窑酒厂新制曲车间和老制曲车间的空气中微生物为研究对象,探讨了新老制曲车间不同环境微生物数量。结果表明,老制曲车间多年富集的微生物数量明显高于新制曲车间,其中曲药库房空气和远离制曲车间50m 左右大环境空气中的霉菌、细菌和酵母菌数量差异均达到显著水平;空发酵房空气中细菌和酵母菌数量差异达到显著水平,而霉菌数量差异不显著;制曲场空气中霉菌、细菌和酵母菌数量差异均不显著。     

现制红茶奶茶开封后微生物动态变化规律初探

为探究现制市售红茶奶茶开封后微生物的动态变化规律,文章以市售3家不同品牌加冰和热红茶奶茶为研究对象,在常温(25℃),自然湿度条件下放置6 h,按照国标方法测定现制红茶奶茶中霉菌、酵母菌,大肠菌群和菌落总数含量。结果表明,与第0 h比,现制加冰红茶奶茶25℃放置6 h,酵母菌、大肠菌群和菌落总数的含量显著增长(p<0.05),含量范围分别为1.2×10²～2.8×10³CFU/m L、3.0×10²～1.4×10⁵CFU/m L、6.4×10⁴～2.7×10⁵CFU/m L,霉菌含量无显著变化(p>0.05),范围为0～15 CFU/m L。热红茶奶茶25℃放置6 h,未检出霉菌和酵母菌,大肠菌群和菌落总数含量范围分别为0～9.9×10⁴CFU/m L、0～1.6×10⁵CFU/m L。现制红茶奶茶开封放置过程中菌落总数和大肠菌群呈增加趋势,加冰红茶奶茶开封后比热红茶奶茶更易滋生大肠菌群、细菌和酵母菌...     

自然制曲的蚕豆曲中优势微生物的分离与初步鉴定

通过各种培养基进行分离培养,对自然制曲蚕豆曲中的细菌总数、芽孢杆菌、酵母菌、霉菌进行计数;对霉菌进行初步鉴定.结果:从自然制曲蚕豆曲中分离出的霉菌,经鉴定为米曲霉和总状毛霉;微生物菌群,以霉菌为主,米曲霉和毛霉数量分别为2.8×107,3.0×106cfu/g;其次为细菌,数量为5.3×104 cfu/g;酵母菌数量为2.6×102 cfu/g;芽孢杆菌:没有检出.     

菊花溶液对发酵甘蓝微生物区系的影响

实验的主要研究内容为不同浓度的菊花溶液(0,0.5%,1%,4%,7%,10%)对蔬菜发酵过程中微生物区系的影响。每隔5天采用稀释涂布平板法对发酵过程中的细菌、乳酸菌、酵母菌、霉菌计数,了解甘蓝发酵过程中微生物数量和种类的变化。测定结果表明:菊花溶液浓度为1%的发酵蔬菜中乳酸菌数量变化最明显,发酵成熟后乳酸菌数量最高,达到13.5854log cfu/mL,霉菌数量较少,仅有3.5498log cfu/mL,因此菊花溶液浓度为1%的泡菜最适合发酵。     

中高温大曲发酵过程微生物消长规律探析

为全面剖析发酵期中高温大曲微生物更迭过程,本文对洋河大曲发酵期各阶段的曲皮和曲心微生物动态消长规律进行了研究。结果表明,曲皮和曲心酵母菌在第1天即达到峰值(10~7cfu/g),受并房和大火前期逐渐升高的曲温影响,曲皮酵母菌从10~5cfu/g下降至10~4cfu/g,大火后期至发酵结束,曲样中鲜少检出酵母菌;曲皮霉菌于主发酵第2天开始大量繁殖,潮火期达到峰值(10~7cfu/g),此时曲心处霉菌仅为10~4cfu/g,这个差距延续至发酵期结束。大火期后,霉菌数量下滑严重,至发酵结束曲皮霉菌仅剩10~4cfu/g;曲皮细菌于发酵第1天即达到顶峰(10~7cfu/g),后续阶段略有下滑,从10~7cfu/g下降至10~6cfu/g,养曲阶段又回升至10~7cfu/g,与曲皮细菌消长规律截然不同,曲心细菌在发酵第2天才有检出,自此至大火前中期,曲心处细菌生长旺盛,达到峰值(10~7cfu/g),大火后期至发酵结束,曲心细菌数略微下降,数量则维持在106cfu/g。     

部分市售粮食制品微生物污染状况监测分析

为明确我国市售大米、小麦粉和挂面这三大类粮食制品中储藏危害微生物的污染状况,确定是否存在潜在安全风险因子,抽检了市场上59个米类产品、37个小麦粉类产品和25个挂面类产品中的霉菌和菌落总数两个微生物指标。霉菌检测结果显示,米类产品污染数量分布于≤10 CFU/g,典型数值为<10 CFU/g;小麦粉类产品污染数量分布于<10～10³ CFU/g,典型数值为10² CFU/g;挂面类产品污染数量分布于<10～10² CFU/g,典型数值为10² CFU/g;菌落总数检测结果显示,米类产品污染数量分布较广,为10～10⁴ CFU/g,典型数值为10² CFU/g;小麦粉类产品污染数量分布于10～10³ CFU/g,其中在10² CFU/g和10³ CFU/g两个数量级的分布比例相等;挂面类产品污染数量分布于10²～10⁴ CFU/g,...     

真菌在大曲酒生产中的应用研究

大曲酒中研究最多的微生物是细菌、霉菌和酵母菌,霉菌与酵母菌同属真菌。真菌在白酒酿造过程中有产酶、生香、产酯等作用,随着微生物技术的发展,白酒行业对真菌的研究不断加深。本文通过收集整理,列出了霉菌和酵母菌在大曲酒制曲和制酒过程中的应用研究情况,并对两者的纯化培养工艺做了简要介绍。     

新建制曲车间环境微生物改善

以西凤酒曲房环境微生物为对象,对比新老曲房内外微生物差异。结果表明:新曲房内外环境中的霉菌及酵母菌浓度普遍低于老曲房。霉菌和酵母菌新车间外比老车间外分别低56.2%和28.3%,新曲房内比老曲房内分别低96.7%和72.2%。通过自制麸曲浸泡液喷洒,对新曲房环境微生物进行定向人工干预,复刻模拟老制曲车间环境后,新建制曲车间内环境微生物有所改善,霉菌浓度已达到老曲房的最小值,酵母菌浓度与老曲房趋于相同。该研究从微生物角度为新曲房大曲的性能稳定及品质提高奠定了基础。     

凤香型白酒生产阶段酒醅微生物群落结构分析研究

本研究利用高通量测序技术结合荧光定量PCR法,对凤香型白酒不同生产阶段的酒醅微生物群落结构进行分析,分离鉴定酒醅中的优势菌种。结果表明：各阶段出池酒醅中细菌的生物量在10⁷～10⁹ copies/g酒醅之间,真菌的生物量在10⁶～10⁸ copies/g酒醅之间,细菌的生物量高于真菌。酒醅中共检测到15个细菌门和6个真菌门,厚壁菌门Firmicutes和子囊菌门Ascomycota为绝对优势菌门;共检测到204个细菌属和140个真菌属,乳杆菌属Lactobacillus为绝对优势细菌属,毕赤酵母属Pichia、单孢酵母属Kazachstania、曲霉属Aspergillus、热子囊菌属Thermoascus、假丝酵母属Candida、德克酵母属Dekkera和纽曼菌属Naumovozyma为优势真菌属。分离鉴定得到36株细菌和25株真菌,其中3种细菌、5种真菌是酒醅中相对丰度排名前十的优势菌种。     

鲜辣椒微生物区系的研究

为在生产中抑制原料辣椒中的有害微生物,对提高辣椒加工产品品质提供理论依据。实验采用GB4789.2-2003、GB4789.15-2003方法分别对细菌、酵母菌和霉菌进行计数,对分离纯化细菌进行鉴定。结果显示:辣椒表面的细菌和酵母菌数量最高,均超过107cfu/g,细菌和酵母菌是优势菌,霉菌数量相对较少。鉴定出辣椒表面细菌以革兰氏阳性菌为主,多为乳酸菌,以乳杆菌为主,也分离到一些革兰氏阴性杆菌,主要是肠杆菌科细菌。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press     

INFOPRINT 2014 was Successfully Held in Dongguan

Sponsored by Printing and Printing Equipment Industries Association of China （PEIAC） and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference （INFOPRINT 2014） was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel.