糙米发酵最佳条件及在乳酸发酵中的应用研究

以糙米为原料,利用微生物发酵的方法研究发酵温度、时间和接种量对发酵糙米中蛋白酶活性的影响、发酵糙米品质变化及其在乳酸发酵中的应用.实验结果表明糙米发酵的最佳条件酵母用量3%,发酵时间6h,发酵温度30℃;对此条件下制成的发酵糙米的感官评定结果是酸甜风味、乳白色、外观比较整齐,氨基酸总含量增加2.05%.发酵糙米有明显促进微生物生长和增加产酸量的作用.     

响应面法优化发酵糙米脂肪酶活性的工艺研究

以糙米为主要原料,通过接种复合微生物进行发酵糙米的生产.采用响应面法设计试验,以脂肪酶活性为指标,确定了糙米发酵的最适条件.试验结果表明,发酵糙米生产工艺的最优条件为:发酵时间4.53 h,发酵温度26.81℃,接种量3.47%,菌种配比(乳酸菌与酵母菌)为2:1.21.     

双边发酵法生产发芽糙米酒的研究

发芽糙米辅以大米为原料,以发芽糙米中的酶为糖化剂,以酿酒酵母为发酵剂,通过双边发酵,研制出一种新型低醇酿造酒。通过对加水比、接种量、培养温度以及发酵周期的研究,确定发芽糙米酒最佳生产条件为:料∶水=1∶2.5;接种量为0.1%;发酵温度为32℃;发酵周期为4d。     

糙米芽制备及其在红曲保健酒中的应用

对糙米芽制备及其红曲保健酒的生产工艺条件进行研究。通过单因素及正交试验,确定糙米发芽、糙米芽汁制备及复合菌种发酵等过程的最佳工艺条件。结果表明,糙米芽制备适宜的工艺条件为25℃浸泡10h、30℃下发芽24h;糙米芽汁制备中,采用70℃液化2h、55℃糖化2h所得糙米汁质量较高;酵母接种量为0.5%(m/V),红曲霉接种量为15%(V/V),在32℃下发酵5d,可得到色香味俱佳的糙米芽红曲保健酿造酒。     

发芽糙米酸奶发酵特性研究

论文以发芽糙米和奶粉为主要原料,发芽糙米经液化、糖化、乳酸发酵等工艺,研究添加了发芽糙米对酸奶的发酵特性以及品质的影响。实验结果表明:在配方为发芽糙米用量10%,脱脂酸奶的用量15%,食用蔗糖3%,酸奶接种量5%,发酵温度42℃,发酵时间为11h时,含菌量是对照的5倍,达到4.1×108cfu/mL,乳酸菌含量比对照组增加了5倍之多且风味良好,说明发芽糙米具有一定的益菌作用,发芽糙米酸奶具有一定的开发价值。     

乳酸菌发酵对糙米蒸煮性能和食用品质的影响

采用乳酸菌发酵降解糙米籽粒表层的的纤维,以改善糙米的吸水性能,提升糙米的蒸煮性能和食用品质。通过单因素实验优化糙米发酵工艺参数,并对糙米发酵前后的形态结构、蒸煮性能、质构、风味等进行研究。结果表明:糙米发酵最佳工艺参数为发酵时间24 h、发酵温度30℃、含水量30%、接种量0.1%,此条件下糙米最佳蒸煮时间较原料糙米缩短了6.46 min,吸水率增加了25.18%,米饭硬度降低了29.63%,黏性升高81.88%,咀嚼性下降了46.86%。发酵破坏了糙米皮层结构的完整性及与内部组织连接的致密性,改善了糙米的吸水性能,降低了糙米饭的硬度,改善了糙米风味。发酵可以使糙米饭更加易煮,有效改善了糙米的蒸煮性能和食用品质。     

青稞饮料的味觉分析

以发芽糙米和鲜牛奶为主原料,经乳酸发酵后、调配成乳酸菌饮料.通过试验确定发芽糙米酶解最佳条件:即酶的添加量为7 μg/g,酶解时间为50 min,酶解温度为90℃.混合液最佳发酵条件为:发芽糙米浆∶牛奶为1∶2,接种量为6％,发酵温度45℃,发酵时间4.5h.选用复合稳定剂进行试验:即0.2％羧甲基纤维素钠(CMC-Na)和0.3％海藻酸丙二醇酯(PGA).发芽糙米乳酸菌饮料的最佳条件为:发芽糙米混合发酵乳用量为50％,白砂糖为11％,柠檬酸为0.4％,感官评分为89分,γ-氨基丁酸含量为1.57 mg/(100 ml).     

短乳杆菌发酵提高糙米中γ-氨基丁酸含量的研究

以获得富含γ-氨基丁酸(GABA)的糙米粉为目的,接种可食用乳酸菌对发酵条件进行优化。通过单因素试验和响应面试验,确定接种短乳杆菌P-14发酵糙米产GABA的最佳条件为:谷氨酸钠(MSG)添加量1%,发酵温度35℃,发酵时间3d,在此条件下,GABA理论含量为864.38mg/100g。经过验证实验,得到GABA含量为(851.24±34.15)mg/100g,与理论含量相近。采用优化后发酵工艺进行发酵的糙米中GABA含量比糙米原料提高了80倍,显示出发酵糙米产GABA的优势。     

发芽糙米乳酸菌饮料的研制

以发芽糙米和鲜牛奶为主原料,经乳酸发酵后、调配成乳酸菌饮料。通过试验确定发芽糙米酶解最佳条件:即酶的添加量为7μg/g,酶解时间为50min,酶解温度为90℃。混合液最佳发酵条件为:发芽糙米浆∶牛奶为1∶2,接种量为6%,发酵温度45℃,发酵时间4.5h。选用复合稳定剂进行试验:即0.2%羧甲基纤维素钠(CMC-Na)和0.3%海藻酸丙二醇酯(PGA)。发芽糙米乳酸菌饮料的最佳条件为:发芽糙米混合发酵乳用量为50%,白砂糖为11%,柠檬酸为0.4%,感官评分为89分,γ-氨基丁酸含量为1.57mg/(100ml)。     

发酵糙米的加工工艺

对用酵母发酵糙米的工艺进行研究。以糙米粉为试验材料,添加水、蜂蜜、盐、大麦芽粉为底物,采用活性酵母液进行发酵试验。以淀粉酶活力作为试验指标,设计包含培养基加水量、发酵温度、时间和接种量四个因素水平,通过正交试验确定糙米发酵培养基的最佳配方和最佳发酵条件。优化的工艺条件为加水量为150%,酵母接种量为4%,发酵温度为30℃,发酵时间为为4 h。糙米酵素中的α-淀粉酶含量最高,达到485 U/g。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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