挤压法制备营养方便米的品质

对挤压工艺制备的方便米和传统工艺生产的商用方便米食用品质对比结果表明．挤压工艺制备的方便米颜色浅白，透明度较低，糊化度高，表观密度较小，复水率稍高；传统工艺生产的商用方便米颜色较白，呈半透明，糊化度低，表观密度较大，复水率稍低．对复水后方便米饭的质构分析和感官评价表明，挤压工艺生产的方便米食用品质，除色泽外，均优于传统工艺生产的商用方便米，其品质接近杂交籼米新鲜米饭．通过强化大豆蛋白、VB1、VA，挤压工艺制备的方便米的营养效价得到提高．     

发芽糙米重组米制备方便米饭的研究

研究双螺杆挤压对发芽糙米重组米复水性能、营养成分及糊化特性的影响,随后以发芽糙米重组米为原料制备方便米饭,研究蒸煮和干燥工序对发芽糙米重组米方便米饭食用品质的影响。结果表明:螺杆转速120 r/min,三、四区挤压温度120℃、物料含水量20%时,发芽糙米重组米复水率最高,且糊化特性优于发芽糙米;相比于发芽糙米,发芽糙米重组米总淀粉、直链淀粉和可溶性蛋白含量下降,总蛋白、粗脂肪、纤维素和γ-氨基丁酸含量几乎不变。米水比1∶1.3、蒸煮30 min时,方便米饭的感官评分最高,且硬度和黏着性适中;蒸煮方便米饭经560 W-60℃微波热风组合干燥速度最快,此时得到的干燥方便米饭复水时间最短,复水率和碘蓝值最高。发芽糙米和发芽糙米重组米制备的方便米饭色泽和香味都较好,但发芽糙米重组米方便米饭的形态、口感和滋味更好。     

工程重组方便米复配机理的研究

长期以来,方便米的复水特性和复水后的食用品质是制约传统工艺发展的主要症结之一,人们为此进行了不懈的努力。本文以大米粉作为主原料,复配食品添加剂,采用挤压技术生产“工程重组米”的新思路,完全克服传统工艺对大米进行表面处理的局限性,试图为制备具有良好品质的方便米另辟蹊径。本文研究了单甘酯(GMS)、大豆卵磷脂(LC)、硬脂酰乳酸钠(SSL)对米粉挤压过程中理化特性的变化以及对制备的方便米复水特性的影响,研究表明随着乳化剂添加量的增加,工程重组米的糊化度(DG)、水溶性碳水化合物(WSC)有所降低。随着GMS的增加,挤出物的膨胀度、水溶性蛋白质(WSP)、吸水指数(WAI)、方便米的复水率下降,硬度增加,而粘度在低于添加量0.8%时上升,高于0.8%时下降。而添加SSL,膨胀度变化较小,WSP、WAI有所增加;添加LC,膨胀度和WAI都有所增加,WSP变化较小。与对照组相比,大豆磷脂和SSL添加量小于0.8%时,复水率有所提高,硬度与粘度下降。     

挤压方便米的径向膨胀率与其复水率、糊化度关系的研究

以早籼米为原料,采用双螺杆挤压技术,研究大米挤出物的径向膨胀率和复水率随挤压加工参数变化规律,同时研究膨胀率与挤压方便米饭复水率、糊化度的关系,以期为挤压方便米饭的生产摸索出方便有效的生产标准。实验表明,不同挤压条件下,径向膨胀率皆和复水率有相同变化趋势,复水率、糊化度亦随膨胀率的变化呈相同变化趋势。研究结果表明,当原料水分32%,进料速度70g/min,螺杆转速150r/min,末端机筒温度92℃的情况下,物料径向膨胀率达到2.19,糊化度达到87.8%,产品色泽接近天然大米,内部具有致密多孔的结构,5min内的复水率达到2.03,复水之后,复水20min之内产品外形保持良好。     

蒸煮工艺处理对高粱复配方便米饭的影响

以粳米、高粱米为原料制成新型方便米饭,采用单因素方法研究蒸煮工艺中复配比、料水比、蒸煮时间对高粱米复配方便米饭品质的影响,并采用正交试验优化最佳的蒸煮工艺。结果表明,在一定范围内,糊化度随着复配比、料水比和蒸煮时间的增加而大幅增大;复水率呈不同程度增加趋势,而感官评分呈先增大后减小趋势。高粱米复配脱水方便米饭的最佳蒸煮工艺参数为:高粱米与粳米复配比例为1:3、蒸煮料水比为1:1.6、蒸煮时间为25 min,此工艺下高粱米复配脱水方便米饭糊化度为90.2%、复水率2.24、感官评分90,综合值202.4。     

双酶组合处理工艺对干燥方便米饭品质影响的研究

本文对干燥方便米饭双酶组合糊化工艺进行了研究。系统研究了浸泡时间、浸泡温度、糊化时间、糊化温度以及碱性蛋白酶和β-淀粉酶的添加量对复水时间和复水效果的影响。通过酶的配方实验获得了复合酶制剂的最佳配比:碱性蛋白酶的浓度为2.66 g/L,β-淀粉酶浓度为0.15 g/L;通过正交实验获得了最佳的糊化工艺条件:利用最优配比酶液浸泡40 min,浸泡温度40℃,糊化时间45 min,糊化温度90℃。在此条件下获得较优品质的方便米饭:碱消值为6.83,复水时间为7 min,提高了方便米饭的食用品质。     

方便米饭湿热处理工艺与复水特性研究

本文研究湿热处理工艺与方便米饭品质和复水特性的关系。结果表明,经不同湿热处理的方便米饭品质和内部水分扩散特性有所不同。浸泡时采用复合改良剂,以一定浓度食盐、糖、明胶或抗老化剂等浸泡,可改善方便米饭的加工性能、复水特性及食用品质。采用常压蒸煮、高压蒸煮和微波蒸煮等不同糊化方法,方便米饭品质特性亦有所差异。     

挤压工艺对保鲜方便米饭品质的影响

以双螺杆挤压机加工保鲜方便米饭,研究了进料糊化度、进料水分含量、进料粒度、螺杆转速对方便米饭品质的影响。通过分析感官评定与质构参数的相关性,确定以硬度和咀嚼性为指标评价挤压保鲜方便米饭的挤压工艺。采用单因素试验和正交试验,优化了挤压工艺条件:进料粒度0.425 mm,进料糊化度50%,进料水分质量分数25%,挤压机螺杆转速90 r/min。在此条件下制备的方便米饭硬度为113.56 g,咀嚼性为63.81。米饭颗粒饱满,色泽晶莹,咀嚼性适中,口感好。     

茯苓营养方便米的研制及其品质分析

将茯苓粉与普通粳米粉以3种比例配伍,通过双螺旋挤压得到长短两种颗粒型茯苓营养方便米,并使用米粒食味计、米饭食味计和RVA快速黏度分析仪等对2种粒型但茯苓组分不同方便米的理化指标、物性指标、淀粉黏滞性、复水性和糊化度进行了检测对比,并对其直链淀粉含量与糊化特性、外观品质、蒸煮理化指标和食味品质之间关系进行了简单的研究分析。结果表明:研制的2种粒型营养方便米均有较高的食味品质,符合人们的食用需求,值得大力推广。     

高粱方便米饭浸泡工艺的优化

以高粱为原料制成新型方便米饭,研究浸泡工艺对高粱方便米饭食用品质的影响并对该工艺进行优化。通过测定复水率和感官评分评价浸泡时间、浸泡温度、β-CD、柠檬酸和Na2CO3对高粱方便米饭品质的影响。结果表明,一定时间的温水浸泡处理能显著增加复水率,提高感官品质。低浓度范围内,复水率和感官评分随β-CD浓度的增加而增大。复水率和感官评分随着柠檬酸浓度的增加而减小。正交试验结果表明,高粱方便米饭的最佳浸泡工艺为40℃浸泡3 h,柠檬酸的添加量为0.15%,β-CD的添加量为1.5%。在此浸泡工艺下制得的高粱方便米饭的口感良好,感官评分为94.3分,复水率为2.30。     

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.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

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 Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.