糯玉米鸡肉发酵香肠的研制

本文以植物乳杆菌和嗜酸乳杆菌为发酵剂,以鸡肉、糯玉米、猪肥膘为原材料研制糯玉米鸡肉发酵香肠。选取糯玉米的添加比例,蔗糖的添加量,发酵剂的添加量,发酵温度,发酵时间,嫩化剂添加量6个条件进行单因素实验,在此基础上选取4个主要的影响条件进行正交实验,确定出最佳工艺条件为:糯玉米添加量10.00%,发酵剂接种量3.00%,蔗糖含量1.50%,发酵温度37℃,发酵时间20 h,嫩化剂的添加量0.004%,此时感官评分为80.3,发酵香肠的p H为4.67,水分含量30.30%,蛋白质含量28.90%,脂肪含量为18.90%,食盐含量2.50%,亚硝酸钠含量14.00 mg/kg,致病菌未检出,且风味和口感良好,符合国家卫生标准。     

茶树菇发酵香肠的研制

将茶树菇切成碎粒添加进肉馅中一起发酵,制得茶树菇发酵香肠。通过正交试验确定发酵香肠的发酵工艺和最佳配方。结果显示,最佳发酵工艺为:发酵剂添加量4%、发酵温度35℃、发酵时间20h、嫩化剂添加量0.006%。发酵香肠的配方为:茶树菇添加量12%、猪肉肥瘦比2∶8、蔗糖添加量3%、玉米淀粉添加量4%。按此工艺和配方制得的产品,经感官评定和理化检测,口感上佳、营养丰富。     

椰子酸奶发酵工艺

以椰浆和全脂奶粉为主要原料,通过原料配比、菌种、发酵温度和时间、蔗糖添加量等单因素试验和正交组合试验设计方法,确定了椰子酸奶的工艺条件:全脂奶粉和椰浆比例为1∶2(即全脂奶粉添加量5%)、蔗糖添加量为8%,采用SH-470乳酸菌植物性发酵剂(按其说明接种量):嗜热链球菌和植物乳杆菌发酵,发酵温度43℃,发酵时间6 h。     

人参枸杞复配发酵饮品的研制

以人参、枸杞为原料,以开菲尔为发酵剂研制人参枸杞复配发酵饮品,在单因素试验的基础上,通过正交试验,以蔗糖添加量、接种量、发酵温度和人参汁与枸杞汁的比例为考察因素,确定最佳发酵工艺。结果表明:在发酵时间为24 h时,各因素对人参枸杞复配发酵饮品感官评定的影响由大到小依次为:接种量、蔗糖添加量、发酵温度、人参浆与枸杞浆的比例。最佳工艺添加为:接种量为6%,蔗糖添加量为6%,发酵温度为26℃,人参浆与枸杞浆的比例为1∶1。在此工艺条件下,产品口感细腻,酸度适中,风味独特。     

鹅肉发酵香肠生产工艺研究

目的:获得鹅肉发酵香肠的生产工艺及技术参数。方法:在鹅肉香肠的制作过程中,添加适当的发酵剂,利用正交试验对其生产工艺进行研究。结果:确定发酵剂为植物乳杆菌和啤酒酵母菌,菌悬液(La:Sa)体积比为2:3,得出最佳的鹅肉香肠制作工艺条件为发酵温度33℃、接种量2.0%、发酵时间36h。结论:该鹅肉发酵香肠的制作工艺条件稳定、可行。     

糯米酒制作凝固型酸奶的工艺研究

试验利用糯米酒制作凝固型酸奶,米酒发酵液的最适灭菌条件为95℃、5min,原料奶总固体物最佳含量16%.对蔗糖添加量、米酒发酵液添加量、发酵温度、发酵时间和发酵剂添加量做单因素试验,以米酒酸奶的感官评价为指标,通过正交试验,得出凝固型米酒酸奶最佳工艺组合蔗糖添加量7%、米酒发酵液添加量18%、发酵剂添加量1%、发酵温度42℃、发酵时间4h.其中米酒发酵液添加量对米酒酸奶品质影响显著.     

巴旦木风味酸奶的研制

以新鲜牛奶、巴旦木浆为原材料,考察巴旦木浆添加量、蔗糖添加量、发酵时间、发酵剂添加量4个因素对巴旦木风味酸奶的影响。以感官评分为响应值,采用响应面法对巴旦木风味酸奶的最佳工艺参数进行优化,结果表明巴旦木风味酸奶的最佳工艺条件为巴旦木浆添加量9%,蔗糖添加量7%,发酵时间4.2 h,的发酵剂添加量3%。在此优化条件下制作的巴旦木酸奶不仅口感绵柔细腻,且具有独特的巴旦木风味,感官评分为89.8分。     

鹅肉香肠的发酵工艺研究

选用发酵乳杆菌和变异微球菌为复合发酵剂生产鹅肉香肠,并以样品感官评分、过氧化值(POV)作为考察指标,在单因素试验分析的基础上,采用多指标正交设计对发酵鹅肉香肠的发酵温度、发酵时间、接种量以及菌种比例进行优化。结果表明:鹅肉香肠的最佳发酵工艺条件为:发酵时间20h、发酵温度25℃、接种量1×107CFU/g、发酵乳杆菌和变异微球菌最佳比例1:1。在此条件下,发酵鹅肉香肠感官评分为96分,POV为2.3meq/kg。在最佳发酵条件下制得的发酵鹅肉香肠的还原力(A700nm)和DPPH自由基的清除率分别是0.45和85.7%,样品抗氧化效果好。     

优化发酵关键工艺对酱鱼品质的影响

在浓度为1×107 cfu/g和接种量为2%的乳酸菌发酵剂的条件下,研究食盐、蔗糖、甜面酱的添加量和发酵时间、发酵温度等关键工艺,对发酵酱鱼品质的具体影响。结果表明:添加量为食盐2%、蔗糖2%、甜面酱10%,发酵时间3 d、发酵温度30℃时发酵生产的酱鱼品质最佳。     

西藏灵菇发酵仙人掌酸牛奶酒的工艺条件研究

将仙人掌果汁以不同的添加比例加入牛奶中,经冷却后接种西藏灵菇发酵剂,针对影响仙人掌酸牛奶酒制品的四个因素即仙人掌汁添加量、发酵剂接种量、发酵温度、发酵时间,通过正交试验筛选出制备功能性仙人掌酸牛奶酒的最佳发酵条件。结果表明:仙人掌果汁添加量为15%,发酵剂接种量为1%,发酵温度22℃,发酵20h时,所得产品的口感、组织状态、风味较好。     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

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.