木瓜酒和木瓜醋发酵工艺及其有机酸组成分析

以光皮木瓜为原料,发酵木瓜干酒,再通过液态深层发酵酿制木瓜醋,确定了木瓜干酒和木瓜醋的发酵工艺,并对木瓜酒和醋主要有机酸进行分析。光皮木瓜经榨汁、调整糖度后进入发酵工序,酒精发酵采用带皮渣半固态发酵方式,条件为加水比例1.5∶1（m/m）、初始糖度18%、果酒干酵母接种量0.1%、在24 ℃条件下发酵64 h,木瓜酒酒度（乙醇体积分数）为9.45%。醋酸发酵采用半连续式液态深层发酵法,调整初始酒度7%,醋酸菌接种量10%,在34 ℃条件下醋酸发酵80 h,木瓜醋总酸度为4.52%;分割留种发酵仅需24 h即可完成醋酸发酵。采用反相高效液相色谱法从木瓜干酒和木瓜醋中检出10 种有机酸,分别是草酸、酒石酸、甲酸、苹果酸、α-酮戊二酸、乳酸、醋酸、柠檬酸、富马酸和琥珀酸。实验确定的发酵工艺以及有机酸的分析与鉴定可为木瓜干酒及木瓜醋产品的开发提供理论依据。     

半自动连续发酵残次鲜红枣醋及其有机酸分析

以残次鲜枣为原料,通过破碎制浆、酒精发酵、半自动连续醋酸发酵等工序加工枣醋,探讨残次鲜枣生产枣醋的可行性。将洗净的残次鲜枣,加1.5倍水打浆后接种0.1%的酿酒活性干酵母进行常温酒精发酵(72h),得到枣酒液酒精度8.07%Vol;枣酒液接种10%的活化醋酸菌菌种,经过60h可完成第一批醋酸发酵;采用分割留种发酵法进行10批次半自动连续醋酸发酵制备红枣醋,发酵周期为30h,各批枣醋平均酸度为4.81g/100 mL。采用反相高效液相色谱法(RP-HPLC)从残次鲜枣果醋中检出10种有机酸,主要为醋酸、乳酸和苹果酸,其有机酸组成和含量与优质鲜枣果醋无明显差异。以残次鲜枣为原料通过半自动连续醋酸发酵法能高效生产红枣醋,品质与优质鲜枣果醋相当,表明该方法可用于枣产区转化残次鲜枣资源生产果醋。     

桃醋液态发酵过程中主要成分及有机酸的变化

以成熟桃为原料,采用液态发酵法酿造原浆桃醋,对"两步法"酿造桃醋过程中主要成分的动态变化进行分析。桃打浆后接种0.05%的果酒酵母带皮渣酒精发酵,在20℃恒温发酵80 h,发酵液酒度为6.07%。醋酸发酵使用自吸式液态深层发酵罐,接种10%活化的醋酸菌菌种,发酵温度34℃,经60 h醋酸发酵,桃醋酸度为3.54%。桃醋发酵液中检出9种有机酸,包括草酸、甲酸、苹果酸、α-酮戊二酸、乳酸、醋酸、柠檬酸、富马酸和琥珀酸,9种有机酸在酒精发酵和醋酸发酵阶段均发生显著变化,对发酵液的酸度和品质产生显著影响。酒精发酵阶段,乳酸大量积累;苹果酸、柠檬酸被消耗显著降低。醋酸发酵阶段酒精大量转化醋酸,醋酸含量显著上升;而其它大部分,如乳酸、苹果酸等有机酸显著降低。试验确定的发酵方法适用于桃醋生产。     

黑莓果醋生产工艺的研究

以黑莓为原料,对黑莓果醋的酿造进行了研究。试验表明,酿造黑莓醋的最适宜工艺条件为酒精发酵阶段糖度18%,接种量0.2g/100g,发酵温度30℃;醋酸发酵阶段,接种量10%,底物浓度6%,发酵温度为33℃。果醋酸度为4.5g/100mL以上。     

野生番石榴果醋加工工艺条件的优化

以野生番石榴为原料,开发营养丰富的保健果醋,研究番石榴果醋的加工工艺,为番石榴的深加工提供一定的理论依据。野生番石榴果实经分选、清洗、破碎打浆、成分调整后进行酒精发酵和醋酸发酵,再经过陈酿、过滤澄清,在60～70℃下杀菌10min,冷却后可生产出具有浓郁野生番石榴香味和醋酸味的番石榴果醋。通过单因素实验和正交实验,对番石榴果醋的酒精发酵、醋酸发酵生产工艺参数进行优化。实验结果表明,酒精发酵的最佳工艺条件为:酵母菌接种量0.15%,糖度18%,发酵温度32℃;醋酸发酵的最佳工艺条件为:醋酸菌接种量10%,初始酒精度7%vol,发酵温度38℃。     

梨醋发酵工艺研究及超滤除菌

以砀山梨为原料,采取自吸式发酵罐深层液态半连续法酿造梨醋,采用单因素和正交试验优化发酵工艺条件,结果表明,果胶酶解处理的最优条件为:p H3.5、温度35℃、果胶酶用量1.8 U/100 m L、酶解3 h;酒精发酵条件:酵母接种量0.35%、原料装液量70%、温度30℃、糖度为20%、发酵4 d;醋酸发酵最佳条件为:半连续发酵,温度为30℃,接种量为10%,分割量为35%,发酵9 d,所得梨醋酸度可达7.0 g/100 m L。膜超滤澄清除菌的操作条件进料温度26℃、压力0.1 MPa、过滤时间1 h。该工艺酿造的梨醋符合国家相关卫生标准,酸味柔和,具有醋香味和梨果的清香,同时保留了梨果中的功能性成分,有一定保健功效。     

欧李醋饮料加工工艺研究

以欧李为主要原料,果葡糖浆和蜂蜜等为辅料,采用液态发酵工艺,对原料进行烫漂处理以降低单宁含量,然后打浆,再经酶解、发酵及调配工艺,制得色泽鲜亮、口感协调、味道柔美的营养保健果醋,钙含量和Vc含量分别高达27.13mg/100m L和12.76mg/100m L。实验从酒精发酵工艺,醋酸发酵最适温度、酒精度、最适接种量及欧李醋饮的最佳配方进行研究,结果表明:最佳酒精发酵工艺为B处理;醋酸发酵最佳工艺为:醋酸菌接种量10%、发酵温度30℃、初始酒精度6%、120r/min摇床发酵6d;欧李醋饮的最佳配方为:欧李汁30%、欧李果醋20%、果葡糖浆20%、蜂蜜5%。     

液态深层发酵酿造枣醋工艺研究

以金丝小枣为原料,采用液体深层发酵方式酿造枣醋,通过研究酿造过程中酒精发酵阶段酒精度和还原糖的变化,醋酸发酵阶段总酸和酒精度的变化,确定了液态深层发酵酿造枣醋的工艺.结果表明,酒精发酵阶段枣浆的初始糖度13.8%,酵母菌接种量0.03%,发酵温度25°C～30°C,发酵3.5 d结束,酒精度为8.4%(v/v).醋酸发酵阶段的初始酒精度为6.3%(v/v),初始酸度为1.5g/100mL(以醋酸计),醋酸菌接种量10%(v/v),发酵温度31℃,通风量600l/h-10001/h,发酵44h结束,最终酸度达到7.82g/100mL.所酿制的枣醋枣香浓郁,营养丰富.     

荔枝保健果醋酿造工艺研究

采用液态深层全发酵法研究了荔枝果醋的酿造工艺。通过正交实验确定了荔枝果醋酿造过程中酒精发酵最佳工艺参数:发酵温度为30℃,SO2添加量为40mg/L,发酵时间为6d,接种量为5%;醋酸发酵最佳工艺参数:搅拌转速为80r/min,发酵温度为33℃,发酵时间为7d,接种量为5%。优化工艺条件下进行10L规模中试发酵,所得产品质量较好。     

固定化菌种发酵生产金柑果醋的研究

以金柑为主要原料,利用固定化菌种进行发酵酿造金柑果醋的研究。实验结果表明利用固定化技术酿造金柑果醋的适宜工艺条件为酒精发酵阶段:糖度18%,固定化酵母菌接种量10%,接种发酵菌种中生香酵母与酿酒酵母的比例1∶1,发酵温度32℃,发酵时间72h;醋酸发酵阶段:起始酒精度8%,固定化醋酸菌接种量10%,醋酸发酵温度33℃,发酵时间72h。     

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