芒果果醋发酵条件的试验研究

对芒果果醋发酵条件进行了研究。结果表明:芒果经预处理后,采用在37℃条件下、1∶15的复水比、含糖量8%的水溶液活化20min后接种进行酒精发酵,酒精发酵的发酵温度30℃、时间48~60h。再经醋酸发酵,发酵温度为30℃、时间72h。可制得的芒果果醋醋酸质量分数5%～7%,Vc含量≥30mg/L。可溶性固形物质量分数3.0%。同时经比较研究认为采用通气搅拌可提高总酸的质量分数(相对静置发酵),通气搅拌和分割加醪取醋可缩短发酵时间,提高转化率。     

涤纶降解工艺的对比研究

基于酯的水解、醇解与酶解反应,对涤纶进行降解回收。实验发现,涤纶在温度100℃、浴比1∶40、搅拌速度2 000 r/min、降解1 h的条件下可被浓度为5 mol/L的氢氧化钠或氢氧化钾降解;在温度260℃、搅拌速度1 600 r/min、丙三醇与涤纶质量比为10、质量分数3%的乙酸锌(相对于涤纶质量)的条件下反应1 h被降解;乙二醇在温度180℃、搅拌速度1 600 r/min、质量分数8%的乙酸锌(相对于涤纶质量)、乙二醇与涤纶质量比为40、时间50 min的条件下可降解涤纶;碱性脂肪酶在温度为50℃下振荡1~4 h可对涤纶产生作用,使其强力下降。通过对各个工艺条件、成本以及方案的优缺点进行比较,最终确定乙二醇降解工艺为最佳方法。     

果酱是季节的琥珀

正晶莹剔透的果酱罐头,保存着一个季节的味道。怕水果过季?那就熬制成果酱吧,它是每一个季节的琥珀。果酱是把水果、糖及酸度调节剂混合后,用超过100℃温度熬制而成的凝胶物质。制作果酱是长时间保存水果的一种方法。被誉为果酱女王的名厨Christine Ferber曾说过:"果酱遵循季节变化、美食节庆与传统的时刻表,满溢带着可口香气的漂亮食材,并用耐心、时间     

搅拌型枳椇子酸奶的工艺优化

以牛乳为主料,加入药食两用的枳椇子,制成口味独特、营养价值高的枳椇子酸奶。通过单因素实验和正交实验确定出枳椇子酸奶最佳工艺流程及工艺参数。鲜牛奶装瓶、(95℃,5 min)杀菌、冷却至43℃、菌种接种量2%发酵、加入质量分数为20%灭菌枳椇子果肉、加入混合稳定剂、搅拌、混匀置于2~4℃的环境冷藏24 h后熟。经此工艺条件研制而成的枳椇子酸奶口味纯正、酸甜适口、含有枳椇子的独特风味。     

冬枣酸奶加工工艺研究

以鲜乳为原料,经乳酸菌发酵制成凝固型酸牛奶后,添加一定比例的冬枣汁搅拌、冷却罐装,即得风味清香、口感好、营养价值丰富的合格的搅拌型冬枣汁酸奶.经研究得:接种菌种为保加利亚乳杆菌和嗜热链球菌(按1:1比例),接种量为3%～5%,发酵温度和发酵时间的最佳组合为41℃～42℃、3 h～4h.     

冷冻的蓝靛果山羊酸奶工艺条件优化

以蓝靛果、山羊奶为试材,采用单因素试验及L9(34)正交试验确定其复合酸奶产品的最优发酵工艺条件,比对其在冷冻与冷藏条件下产品质量稳定性,形成冷冻的蓝靛果山羊酸奶酿造工艺。试验结果表明:最优发酵工艺为蓝靛果果酱6%、蔗糖7%、接种量4%、发酵时间4.5 h、发酵温度43℃,按此参数生产的蓝靛果山羊酸奶感官评分达98分,理化指标与卫生指标均达到GB 19302-2010《食品安全国家标准发酵乳》要求,具有蓝靛果和酸奶特有的风味。产品在-18℃~-20℃条件下冷冻贮藏,比0℃~4℃条件下冷藏,其质量更稳定。制成冷冻的蓝靛果山羊酸奶可显著改善山羊奶膻味、实现营养与保健功效互补,提高产品附加值。     

营养胡萝卜酱的制法

以往果酱多用水果之类制成的,故品类受到一定限制。 以胡萝卜作主原料制成果酱,不仅可以扩大果酱的种类,同时由于胡萝卜物美价廉,取材容易,制成的果酱的成本也低。尤其对装饰点缀水点心之类,更有独特作用。此种胡萝卜酱独有的浓橙黄色,其鲜艳之色,     

红树莓果酱注芯戚风蛋糕的配方及工艺研究

对红树莓果酱注芯戚风蛋糕的配方及制作工艺进行研究。通过单因素试验、正交试验以及感官评价的方法分别确定了戚风蛋糕的最佳配方及制作工艺为:面粉50 g、鸡蛋110 g、白砂糖50 g、牛奶35 g、植物油20 g、塔塔粉0.5 g、盐1.0 g、泡打粉1.0 g,在上火160℃、下火150℃下焙烤30 min;红树莓果酱的最佳配方为:红树莓500 g、白砂糖200 g、淀粉50 g、柠檬酸0.25 g。最佳注入果酱时间为蛋糕烤熟后的20 min,最佳注入果酱量为蛋糕质量的20%。在此配方及工艺下得到一种颜色金黄、馅料鲜红明艳,风味独特、营养丰富的红树莓果酱注芯戚风蛋糕。     

高温加热对玉米淀粉糊化特性的影响

针对高温加热对玉米淀粉的影响进行分析。采用"120℃加热1~10 h"和"120℃~200℃加热1 h"两种方案对原淀粉进行处理,并使用偏光显微镜和Brabender黏度仪测试淀粉的颗粒形貌、偏光十字和糊化曲线。结果表明:淀粉的颗粒形貌无明显变化,只是在120℃下加热10 h或200℃加热1 h后,淀粉颗粒的棱角受到一定程度的破坏,变得比较圆滑;在120℃下加热8~10 h或在180℃~200℃下加热1 h后,淀粉颗粒的偏光十字逐渐模糊,少数淀粉颗粒发生了非晶化现象;随着加热时间的延长或温度的提高,糊化温度先增加后降低,而峰值黏度、热糊黏度和最终黏度都显著降低。     

韦伯灵芝漆酶生产中试研究

以韦伯灵芝(Ganoderma weberianum)TZC-1为生产菌株,在前期优化的摇瓶培养条件和5 L发酵罐小试生产工艺条件的基础上,对该菌株在50 L发酵罐进行中试放大,确定韦伯灵芝漆酶在50 L发酵罐的中试发酵工艺参数。结果表明:以3 d种龄种子按8%的接种量转接至发酵罐进行中试发酵,发酵温度28℃,装液量30L,采用分阶段控制p H和溶解氧浓度(DO)的策略,发酵初期(0~48 h)p H控制在6.0,48 h后p H控制在4.5~5.0范围内;0~36 h内控制搅拌转速100 r/min,通气量10 L/min;36~72 h内控制搅拌转速150 r/min,通气量15 L/min;72~96 h内控制搅拌转速200 r/min,通气量20 L/min;96 h至发酵结束搅拌转速250 r/min,通气量15L/min。发酵前72 h DO保持在15%~30%有利于菌丝生长,72 h后DO保持在10~15%有利于漆酶的积累。发酵144 h选择放罐,可获得18.8 L发酵原液,其漆酶活力可达27 667.7 U/L,是摇瓶发酵水平的2.5倍。     

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.     

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.     

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 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.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

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