中心组合和响应面法优化衢州柑桔果酒生产工艺

目的:为充分利用衢州柑桔资源,以柑桔汁为主要原料,葡萄酒活性干酵母为酿造菌种,研制发酵型果酒.方法:通过研究初始发酵pH值、干浸出物、接种量和发酵温度等单因素对柑桔酒发酵指标--酒精度、总浸出物、还原糖、酸度、SO2、甲醇等及风味的影响,再通过中心组合试验设计和响应面分析优化获得最佳发酵工艺.结果:最佳生产工艺参数:接种量0.8g/L,可溶性固形物16°Bx(加蔗糖),26℃发酵5 d.确定柑桔果酒的技术指标是:pH 3.6,乙醇体积分数8.5%～8.9%;还原糖1.804 g/L,总氮3.25 g/L,总干浸出物46.0 g/L,总酸0.68 g/L,总SO2质量浓度72mg/L,pH 3.5;游离SO2质量浓度36mg/L,甲醇0.8mg/L,VC 0.1386 g/L,透光率100%.结论:酿造的柑桔果酒色泽金黄、清亮透明,有独特的柑桔果香,重要指标符合国家标准,工艺条件适合扩大生产.     

酿酒酵母对乌饭树果酒发酵过程及果酒品质的影响

以乌饭树果实为原料,通过考察菌体生长情况、总糖和酒精度等多项指标,结合乌饭树果酒酒体成分分析和感官评定,筛选出适合酿造乌饭树果酒的优良菌株。研究发现,酿酒酵母Y3生长繁殖快,降糖和产酒精能力强,仅264h就使总糖浓度降至29.6g/L,酒精度达到7.18%(v/v),发酵后综合感官性能较好,适宜作为乌饭树果酒的起始发酵菌株,以此菌株所制得果酒中花色苷(119.2mg/L)、总酚(5158.2mg/L)和黄酮(5.6mg/L)含量均处于较高水平,同时具有较好乌饭树果实香气。     

分离菌株在荔枝果酒酿造中的应用

研究了本实验室自行分离的4株酵母菌株在荔枝果汁中的发酵性能,通过对发酵过程中各理化指标进行检测,并对新酒进行品评,最终确定4号菌株SCY1比较适合用于荔枝果酒的酿造.以该菌株发酵后的果汁残糖含量2.6 g/L,其中还原糖含量为1.15 g/L;pH值为3.69,总酸为6.9 g/L,其中挥发酸含量为0.66 g/L;酒精度为13.5%Vol;总SO2含量为35 mg/L,其中游离SO2含量为21 mg/L;干浸出物含量为23.8%;感官评定得分90.6分.     

三叶木通果酒酿造工艺研究

参照较为成熟的葡萄酒酿造工艺进行三叶木通果酒的酿造,以期为生产实际提供参考。以三叶木通果实为原料,将其打浆、去籽、过滤后,选用陈酿型干红葡萄酒专用酵母进行发酵酿造三叶木通果酒。研究表明,发酵温度23~28℃,主发酵时间9 d,果胶酶用量20 mg/L,SO2用量50 mg/L,调整果浆的糖度至22%,酵母接种量0.2 g/L,皂土用量0.8 g/L,得到成品三叶木通果酒。成品酒液清亮透明,酒色淡黄,无悬浮物,酒香浓郁;酸度为10.61 g/L,多酚含量0.116 mg/m L,并具有良好的自由基清除活性。     

野生猕猴桃干酒酿造工艺

以野生猕猴桃为原料研制猕猴桃干酒,对果酒酿造工艺参数进行研究。结果表明,果酒酵母1596 适于用作酿制猕猴桃干酒的发酵菌种;果酒发酵最佳工艺参数为SO2 添加量50mg/L、酵母接种量8%、发酵温度18～22℃;降酸工艺：壳聚糖(11g/L)、酒石酸钾(6g/L)联合降酸效果为佳;澄清工艺：果胶酶(质量分数0.1%)与皂土(3g/L)一同添加效果较好,澄清48h,透光率为94.5%。     

脐橙全汁果酒酿造技术研究

以脐橙为原料,对脐橙全汁果酒的酿造工艺进行研究.结果表明,果胶酶用量、SO2添加量、酵母接种量及发酵温度等条件对脐橙果酒品质影响较大;正交实验结果表明,在发酵温度为24℃、SO2用量为80 mg/L、果胶酶用量为50 mg/L、酵母接种量为0.5 g/L的条件下,可制得色泽金黄的优质脐橙全汁果酒.     

感官评价法在石榴果酒研制中的应用

以石榴为原料生产果酒,研究发酵温度、SO2、酵母、pH值、陈酿方法等因素对石榴果酒品质的影响,采用模糊数学感官质量评价方法筛选出石榴果酒的最优生产工艺为:发酵温度25℃,SO2浓度75 mg/L,酵母0.20%,pH4.0,交替变温贮藏陈酿.     

芒果胡萝卜复合果酒发酵工艺的研究

以芒果和胡萝卜为原料酿造复合果酒,并对其发酵工艺进行研究。采用单因素实验和响应面优化试验,分析原料比、SO₂添加量、初始糖度、初始pH、酵母添加量对复合果酒发酵的影响,并得到最优发酵条件。结果表明,最佳发酵条件为:芒果与胡萝卜原料比例为2:1(V/V)、SO₂添加量为55 mg/L、初始糖度为24%、初始pH为3.5、酵母接种量为0.12%。在此最优条件下,芒果胡萝卜复合果酒酒精度为13.62% vol、残糖4.6 g/L、总酸8.8 g/L、干浸出物23.0 g/L、甲醇98 mg/L。酒体色泽橙黄饱满、透明清亮,有浓郁的果香和酒香,口感甘甜醇厚。     

桑椹果酒发酵工艺条件的研究

以成熟桑椹果浆为主要原料,以酵母 1308 作为菌种发酵,研究酿制桑椹果酒的发酵工艺条件和澄清方式.结果表明:采用果浆为原料,酵母用量为8%,发酵温度为 28℃,发酵前调糖至 180 g/L,发酵中 SO2 添加量控制在 75 mg/L,发酵 4 d 后酒精度可达 12%(v/v),可用 0.6%皂土直接澄清处理.产品符合相关标准.     

发酵及贮藏条件对蓝莓果酒花色苷稳定性的影响及其抗氧化性研究

通过探讨发酵时间、发酵温度、SO2添加量、pH、酵母添加量等发酵参数对蓝莓果酒花色苷含量的影响,并分别以花色苷保存率及自由基清除率为依据,对蓝莓果酒成品中花色苷的抗氧化性及稳定性影响因素进行研究,为蓝莓果酒品质的提升及生产优化提供参考。结果显示,最佳蓝莓果酒发酵条件为发酵时间8 d、发酵温度22 ℃、SO2添加量100 mg/L、初始pH值为3.5、酵母添加量0.4%。在此优化条件下,花色苷含量为46.47 mg/100 mL,酒精度为12.76%vol。蓝莓果酒花色苷分别在pH为3、30 ℃以下、避光、隔氧、蔗糖添加量为10 mg/L的条件下比较稳定;蓝莓果酒的1,1-二苯基-2-三硝基苯肼（DPPH）自由基、羟基自由基、超氧阴离子自由基清除能力半抑制浓度（IC50值）分别为16.19 μg/mL、43.61 μg/mL、61.84 μg/mL,总抗氧化能力强于维生素C,因此具有较好的抗氧化活性。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.