苦瓜汁清凉饮料的研制

以苦瓜为主要原料,添加适量的蜂蜜、白砂糖及其它辅料,研制出口感清爽、风味独特、清凉降热、营养丰富、品质稳定的苦瓜汁清凉饮料。本试验对生产工艺、关键技术、抗氧化、稳定剂选择进行研究,工艺独特,有效解决了苦瓜脱苦、护色、稳定等实际技术问题,提出较佳的配方与生产工艺参数要点。     

湿法涂层制备涤纶洁净服面料

采用聚偏氟乙烯(PVDF)涂层液对涤纶织物进行湿法涂层以制备洁净服面料,讨论各工艺因素对涂层面料性能的影响.试验获得的优化工艺条件为:PVDF用量14%,添加剂LiCl 3%,预挥发时间30s,凝固浴的组成为氯化钠:去离子水=5:95,涂层量5-7g/m2.采用优化工艺制得的洁净服面料,滤尘性高达90%,透湿和透气性也较好.     

冷榨法和酶解法提取辣木油的应用领域研究

对冷榨法和酶解法提取的辣木油进行氧化稳定性、维生素E含量和清除DPPH自由基能力分析,探讨不同方法提取的辣木油的最适应用领域。结果表明:冷榨辣木油在120℃的氧化稳定性达到34. 23 h,酶解辣木油在100℃时的氧化稳定性仅为3. 64 h;冷榨辣木油中几乎不含维生素E,酶解辣木油维生素E含量为66. 7μg/m L;酶解辣木油清除DPPH自由基的IC_(50)为31. 98μL,远低于冷榨辣木油的134. 81μL,说明酶解辣木油清除DPPH自由基的能力显著高于冷榨辣木油的;未经精制的冷榨辣木油呈深黄色且有一定的难闻气味,而酶解辣木油则呈浅黄色且清亮、无异味。鉴于以上特点,冷榨法提取的辣木油在烘培和煎炸甚至工业用油等方面具有较好的开发和应用前景,酶解法提取的辣木油更适合用于化妆品用油。     

不同加热非燃烧再造烟叶特性研究

为更好地了解加热非燃烧烟草材料特性,收集了造纸法、辊压法、稠浆法3种工艺制造的加热非燃烧再造烟叶烟草材料,从微观结构、纤维形态、抗张性能、再造烟叶化学成分、烟气化学成分、感官质量等方面进行了系统研究。结果表明,造纸法加热非燃烧再造烟叶的微观结构及纤维形态与其他2种截然不同,主要是纤维交织形成的网状结构,辊压法与稠浆法加热非燃烧再造烟叶的微观结构主要是烟草颗粒结聚形成的不平整平面,三者的抗张强度与断裂拉伸伸长率呈反比;3种加热非燃烧再造烟叶的水分及甘油含量均较高,其对应烟气中的水分及甘油含量亦然,且3种再造烟叶和其对应烟气中水分及甘油含量呈正比关系,3种再造烟叶烟气中除甘油焦油释放量均明显低于传统烤烟型卷烟;辊压法和稠浆法加热非燃烧再造烟叶的综合感官质量接近,均优于造纸法的。     

Characteristics of functional brown rice prepared by parboiling and microwave drying

Brown rice (BR) is well known for its functional properties; however, it is considered unsuitable for consumption in modern diet owing to its hard texture, low digestibility, and high lipid peroxidation. In this study, we investigated the physicochemical properties, and cooking and storage characteristics of functional BR prepared by parboiling (100°C, 15 min) and microwave drying (100 kW, 8 rpm, 91°C, 40 min) processes. These processes significantly increased resistant starch (RS) content by 1.5-fold and total dietary fiber (TDF) content by 1.8-fold; Parboiling and microwave drying processes increased the umami taste by 10% using electronic tongue and decreased the hardness by 10% using texture analyzer, respectively. Additionally, irrespective of the storage duration, these processes remarkably decreased acidity and bacterial counts in the parboiled BR group compared to that in the BR group. Presumably, higher RS and TDF contents, enhanced umami taste, and longer shelf-life of BR would help patients with obesity and diabetes, and industries developing relevant high-value food products.     

Cactus pear peel snacks prepared by instant pressure drop texturing: Effect of process variables on bioactive compounds and functional properties

Cactus pear (Opuntia ficus-indica) has a growing interest from both food manufacturers and consumers due to its medicinal and functional traits. Peel is a major waste from cactus pear juice industry accounting for about 38?% of the fruit weight. New concept of snacks preparation has been developed using instant controlled pressure drop (Détente instantanée controlee, DIC) techniques that provide a texturing stage between initial and final hot air drying stages. In this study, the application of DIC of cactus pear peel (CPP) was performed to be used as starch-free snacks with functional attributes. DIC resulted in high crispness CPP snacks with improved structural and nutritional attributes as well as high relative expansion ratio (up to 21 times). DIC expanded CPP snacks exhibited cutting force (3.34 N) that was much lower than untreated CPP (19.41 N). It is worth noting that optimized DIC treatment (P?=?0.6 MPa for t?=?15 s) allowed more availability of phenolic compounds and β-carotene by 83 and 551?%, respectively. In addition, antioxidant activity was increased up to 53?%. Results showed that steam pressure had significant effect on fat and alcohol insoluble solids (AIS) contents, wherein the correlation coefficients revealed critical relationships between structural and biochemical availabilities. Therefore, DIC could be used as an innovative technology to value this by-product leading to manufacture of crispy CPP snacks with high nutritious quality. There was a significant difference among the DIC treated and untreated CPP in respect to sensory properties, DIC treated CPP at operation conditions of saturated steam pressure?=?0.6 MPa and processing time?=?15 had the highest acceptability.     

Metabolism of iodine iodophor in the thyroid gland

As evidenced by animal experiments (Wistar rats), the iodophore iodine of the commercial product Jodonal-M is bound by the thyroid gland, if administered with the drinking water. When drinking water containing 2 mg/l iodophore iodine was given, the thyroid glands of the experimental animals bound 1.19%; and those of the control animals, 4.68% 131I. When drinking water containing 1 mg/l iodophore iodine was administered, the thyroid glands of the experimental animals bound 1.90%; and those of the control animals, 6.77% 131I. It is concluded that the iodophore iodine which passes over to the milk during teat disinfection is bound by the thyroid glands in a similar manner and takes part in the formation of the thyroid hormones just as the "native" iodine of the milk.     

活性冷轧堆染色的染料和工艺优选

纯棉机织物冷轧堆染色早有应用,但仍缺少染料与工艺选择较明确的理论指导。通过研究活性染料类型、碱剂种类和堆置时间对纯棉机织物冷轧堆染色的影响,重点分析不同碱剂和堆置时间对活性黄3RS、汽巴克隆红C-2BL、青RGB和海军蓝BES等4种不同类型活性染料染色色深和固色率的影响,给出的最佳染色工艺为:活性黄3RS和汽巴克隆红C-2BL以纯碱40 g/L为碱剂,堆置时间分别为15 h和10 h;RGB青和BES海军蓝则采用烧碱4 g/L和纯碱40 g/L混合碱剂,堆置15 h。     

电解法制备超细铜粉的工艺研究

采用脉冲电解法,在硫酸铜与硫酸混合电解溶液体系中,就不同脉冲电解参数对阴极铜粉形貌和粒度的影响进行了研究.实验获得合适的脉冲参数为平均电流密度i=600 A/m2,脉冲宽度ton=8ms,占空比为1∶3,在此条件下,所得铜粉平均粒度为0.87μm,有90%颗粒粒径小于1.25μm,阴极沉积出的铜粉颗粒粒度在0.24~1.79μm之间,粒度分布均匀.     

复合酶解米渣制备蛋白肽的理化与功能性质研究

以米渣为原料,采用复合酶解法制备高水溶性米渣蛋白肽,并对其理化与功能性质进行了分析。结果表明:米渣蛋白肽中总肽含量为88.93%,短肽含量为13.05%,总糖含量为3.14%;氨基酸组成合理,能很好地满足体内营养需要;水中溶解度在pH9.0时最大,为99.15%;乳化性及乳化稳定性均呈现较好变化趋势,乳化性在pH9.0时最大,乳化稳定性在pH11.0时最大。     

低温等离子体对蓝圆鲹在冷藏过程中的品质影响

目的 研究低温等离子体(atmospheric cold plasma, ACP)对蓝圆鲹在冷藏过程中品质变化的影响。方法 以蓝圆鲹为研究对象,采用介质阻挡放电低温等离子体设备对其进行处理(处理组),新鲜蓝圆鲹为对照组,4℃±1℃的条件下分别贮藏0、2、4、6、8、10 d,通过样品pH、持水力(water holding capacity, WHC)、菌落总数、挥发性盐基氮(total volatile basic nitrogen, TVB-N)、硫代巴比妥酸(thiobarbituric acid, TBARS)值、组胺含量、感官评价等指标来分析蓝圆鲹在冷藏期间的品质变化。结果 随着贮藏时间的延长,两组样品pH呈先下降后上升的趋势;菌落总数由初始值2.97 lg(CFU/g)和3.00 lg(CFU/g)分别上升到6.10 lg(CFU/g)和6.72 lg(CFU/g),处理组菌落总数上升速度较缓;TVB-N值和组胺含量均呈上升的趋势,且随着贮藏时间的延长,对照组比处理组上升速度更为明显;持水力和感官评分随着贮藏时间的延长而明显下降;TBARS值随着贮藏时间的延长而增加,且处理组的TBARS值始终高于对照组。结论 低温等离子体处理能够有效地保持蓝圆鲹的鲜度,尤其是在抑制微生物的增殖方面有较大优势,能够延长蓝圆鲹的货架期至少2 d。本研究为延长蓝圆鲹的货架期提供了一定的理论基础。     

Whole-grain corn tortilla prepared using an ecological nixtamalisation process and its impact on the nutritional value

Corn tortillas are produced using the traditional nixtamalisation process (TP). Nevertheless, one of the greatest problems that the tortilla industry faces is the high level of losses of solids. The aim of this research was to evaluate the nutritional value of a whole-grain tortilla, produced using an ecological process (EP). In the EP corn was cooked at 90 °C with 1.8% (w/w) calcium sulphate. The grains were steeped, washed and grounded to obtain the masa, which was baked to produce tortillas. Also, tortillas were prepared using the TP and following the same steps as those used in the EP, except that 1.0% (w/w) of calcium hydroxide was used. The tortillas from EP retained 14.05, 6.03, and 54.02% more fat, protein and fibre than tortillas produced by the TP. The PER value of rats fed whole-grain tortillas (1.81) was not different from that of rats fed the traditional tortillas (1.85).     

Physicochemical and functional properties of lentil protein isolates prepared by different drying methods

Lentil protein isolate (LPI) extract was converted into powder by freeze drying, spray drying and vacuum drying. Differences in particle size distribution, protein subunit composition and colour and surface morphology were observed amongst the three drying methods. Spray and freeze-dried LPI powders exhibited higher solubility (81% and 78%, respectively) compared to vacuum dried powders (50%). The spray dried powders showed a low water absorption capacity (0.43 ± 0.02 g/g) compared to freeze (0.48 ± 0.02 g/g) and vacuum-dried (0.47 ± 0.01 g/g) LPI powders. Spray and freeze-dried powders displayed better gelation ability and higher gel strength, compared to vacuum-dried powder. Both spray and freeze-dried gels showed typical viscoelastic gel characteristics, with G′ dominating over G″ and very low loss tangent. The holding time required for gelation of vacuum dried powder at 90 °C was significantly longer, compared to spray and freeze dried powders. Hence, drying methods used for preparation of lentil protein isolate powders can affect physicochemical and associated functional properties.     

冷镦线材的退火工艺

介绍紧固件用冷镦线材的退火工艺。退火工艺控制要点:(1)完全退火需加热至Ac3以上28℃,碳素钢选用Ac3以上30～50℃,合金结构钢选用Ac3以上50～80℃。(2)球化退火将中碳钢、低合金钢加热到Ac1以上20～40℃或Ac1以下13～26℃,保温后缓冷至550℃以下、空冷或在Ar1以下长时间等温后冷却。(3)中间退火。再结晶退火是将钢材加热至Ac1以下约13℃,碳素钢一般为650～700℃;去应力退火一般将钢材以100～150℃/h的速度升温至500～650℃,保温2～4 h,随炉缓冷至200～300℃出炉。球化退火工艺节能、环保、生产周期短,是未来紧固件生产和研究的主要方向。     

Structure and functional properties of rice protein–dextran conjugates prepared by the Maillard reaction

Dextran was grafted on to rice protein (RP) by the wet‐heating Maillard reaction, and the structure and functional properties of the rice protein–dextran conjugates (RPDCs) were investigated. The RPDCs obtained by the Maillard reaction exhibited superior functionality compared with original RP. The solubility, emulsifying activity index, emulsifying stability index, foaming activity index and foaming stability of the RPDCs increased by factors of 7.50, 1.79, 2.20, 1.69 and 2.01, respectively, compared to original RP. The molecular weight, particle size distribution, surface hydrophobicity, secondary structures, amino acid compositions and chemical bonds of RPDCs were also characterised. The structure–function relationship was preliminary discussed, and the relationship suggests that the improvements in the functional properties were closely related to structural changes.     

不同干燥方法制备的星油藤分离蛋白功能性质的比较研究

以星油藤饼为原料,分别采用真空冷冻干燥和喷雾干燥的方法制备星油藤分离蛋白。研究了温度、p H、质量浓度对两种干燥方法制备的星油藤分离蛋白功能性质的影响并进行比较。结果表明:两种方法制备的星油藤分离蛋白的溶解度和吸油性在55℃时最大;持水性在p H 7时最大;黏度随温度的升高而降低;起泡性和乳化活性、乳化稳定性均随蛋白质质量浓度的升高而增大。真空冷冻干燥样品的吸油性、持水性、溶解性、起泡性大于喷雾干燥的样品;其乳化活性与乳化稳定性高于喷雾干燥的样品。     

The role of beliefs in purchasing process of functional foods

This study utilizes food values in conjunction with willingness to pay (WTP) measures to identify consumers’ subjective beliefs about functional foods. We conducted a non-hypothetical, second price experimental auction (i.e., a Vickrey auction) to estimate WTP for a new functional snack made with white lupine and citrus fiber. A sample of 156 consumers was surveyed in Catania, Sicily (Italy) in July 2015. The findings of the economic experiment reveal a WTP premium for the new functional snack, a premium which depends on functional components but also on other characteristics that go beyond intrinsic healthy properties. Consumers’ WTP for functional foods significantly varies with food values related to origin, safety, naturalness, price, etc., which implies consumers have different subjective beliefs about functional and non-functional foods. These findings have implications for the food sector attempting to design and promote consumption of functional foods, and suggest health is not the only factor motivating functional food purchases.     

The behaviour of the protein complex throughout the technological process in the production of cooked cold meats

Protein composition was examined in order to find markers that could be useful in technology optimization. The behaviour of sarcoplasmic and myofibrillar proteins during the processing of roast pork was studied at the various processing steps, utilising some electrophoretic (SDS–PAGE, 2DE and IEF) and thermometric (DSC) techniques and evaluating the content of amino acids produced. The relevance of desmin as a marker of structural modification was emphasised. The extraction of myofibrillar proteins by brine, the formation of a protein network at 62 °C and the evaluation of the exudate produced during cooking are the crucial steps that should be monitored when a new industrial process is to be optimised.     

The behaviour of the protein complex throughout the technological process in the production of cooked cold meats

Protein composition was examined in order to find markers that could be useful in technology optimization. The behaviour of sarcoplasmic and myofibrillar proteins during the processing of roast pork was studied at the various processing steps, utilising some electrophoretic (SDS–PAGE, 2DE and IEF) and thermometric (DSC) techniques and evaluating the content of amino acids produced. The relevance of desmin as a marker of structural modification was emphasised. The extraction of myofibrillar proteins by brine, the formation of a protein network at 62 °C and the evaluation of the exudate produced during cooking are the crucial steps that should be monitored when a new industrial process is to be optimised.     

Modification of myofibrillar protein functional properties prepared by various strategies: A comprehensive review

Today, both consumers and food industry producers have exhibited an ever-growing interest in improving and broadening the functional performance of proteins in food industry. Myofibrillar protein (MP) is mainly responsible for texture, yield and organoleptic characteristics of final meat products. To increase functional properties of MP, technological and nutritional improvement of MP is needed to modify its structure and functionalities. Considerable approaches, including additives, oxidation treatments, and novel food processing technologies, have been utilized to modify its functional properties to manufacture acceptable meat products with lower cost and more desirable nutritional characteristics. However, a comprehensive summary of structural and functional changes of MP in response to different modification strategies is still lacking. Hence, in this review paper, our main goal is first to provide an overview of the functional characteristics of MP. Then, this review will mainly discuss the current knowledge on the functional changes of MP caused by various modification methods and will present some examples of previous works and recent progress. Finally, future outlooks are presented to tailor the manufacture of functionality enhanced and value-added muscle-based products and enable modified MP can be applied as a novel meat ingredient in food industry.