中年进补餐谱

营养过剩成为现代人的健康大敌。由于过量摄入高蛋白、高脂肪、高糖类 等高营养物质,过剩的营养在体内产生大量的酸性物质,破坏了体内酸碱平衡, 导致酸性体质。酸性体质是产生高血压、糖尿病、心脑血管疾病、高血脂、痛风、 癌症等现代文明病的主要根源之一。预防酸性体质首先要从饮食开始,注意酸 性食物和碱性食物的合理搭配。 属于碱性的常见食物有:菠菜、卷心菜、萝卜、青笋、胡萝卜、马铃薯、黄瓜、 南瓜、豆腐、豌豆、赤豆、绿豆、山芋、甘薯、四季豆、藕、栗子、洋葱、茄子、香菇、 牛奶、蛋白、橘子、葡萄、香蕉、苹果、柿子等。 属于酸性的常见食物有:牛肉、猪肉、鸡肉、蛋黄、牡蛎、鳝鱼、糙米、 面条、面包、蚕豆、章鱼、泥鳅、虾、蟹、鱿鱼、鸭肉、紫菜、白糖、啤酒等。     

将粗饲料变成高效营养饲料的几种方法

自然界的天然粗饲料,如各种农作物的秸秆、皮、壳、芯;树木、瓜果的茎、叶、籽、壳、藤蔓、锯末;动物的蹄、毛、骨、角、下杂等都是发展养殖业的廉价的、取之不尽的饲料资源。这些粗饲料富含大量的蛋白质、氨基酸类、维生     

长效缓释二氧化氯在食品保鲜防腐中的应用研究

持续0.5mg/L左右的二氧化氯对熟肉、熟虾、熟鱼、熟豆腐、米饭、馒头、面包、蛋糕、黄瓜、西红柿、桃等保鲜效果是理想的;对生肉、生虾、生鱼、生豆腐、盐水鸭保鲜效果比对照好;对白果、板栗、核桃、花生米、玉米、绿豆、葵花子、稻米、小麦粒等的防霉效果是很好的。     

炎夏吃“苦”有11大保健功效

近年来,苦味食物越来越受到人们的青睐,这是有科学根据的。苦味食物"家族"庞大,可供食用的苦味食品很多,如生菜、苦瓜、芹菜、苦笋、莴苣、芥蓝菜、油麦菜、芥兰、丝瓜、葫芦、瓠子、苜蓿、香椿、荆芥、芝麻叶、牛蒡根、蒲公英、慈菇等苦味菜,莲子、百合、薄荷、菊花、杏仁、李子、橘皮、槟榔、黑枣、米醋、绿茶、咖啡、可可、啤酒、苦丁茶、绞股蓝茶等果品和     

21世纪纺织装饰品热点产品及开发

当前纺织装饰品开发的重点是:有利人们的健康、无污染环境、突现个性、祟尚创新及高技术含量的产品。如,拒水、拒油、耐污、防火、透湿、排汗、速干、抗菌、防臭、防蚊、抗紫外线、远红外、耐燃、防皱、耐磨、抗静电、特殊保暖等。     

歌星的饮食选择

唱歌需有好的声带。然而人的声带很娇嫩,受着多种因素的影响,其中饮食是重要因素之一。 (一) 那么,哪些食物不利于歌唱发声呢?首先是酒、葱、蒜、烟、炒花生、炒葵花子、臭豆腐、肥肉和过咸的食品;而辣椒、酱豆腐、大油、甜食、椿芽、韭菜、蒜苗、鱼、羊肉、虾、醋、芥茉对嗓子的影响也不可忽视。饮食影响嗓音的主要表现有:嗓子干、口渴、痰多、糊嗓、歌唱时嗓音发堵、发木、发紧、发闷,出现劈音、转音、失音、甚至嘶哑。     

哪些蔬菜起源于我国,哪些由国外传入?

我国幅原辽阔,历史悠久,是一个拥有多种蔬菜的国家。现在,我国栽培的 重要蔬菜作物有116种之多,其中的有57种起源于我国。 原产我国的蔬菜有:白菜、萝卜、韭菜、冬寒菜、蓬菜、茭白、竹笋、荠菜、茼蒿、毛豆、芥蓝、蒲菜、薤菜、草石蚕、水芹、金针菜、慈菇、莼菜、荷、紫苏、芋、百合、山药、丝葱等。     

国家建筑材料工业局咸阳非金属矿研究所

(一)概况国家建筑材料工业局咸阳非金属矿研究所是从事非金属矿应用技术研究、开发的综合性科研单位,下设采矿、选矿、制品、标准、机械、电气、情报等专业研究室。研究方向:石棉、石墨、石膏、滑石、高岭土、膨润土、硅藻土、云母、夕线石、重晶石、石榴子石、蛋白石等多种非金属矿物在采矿、选矿、制品、矿物综合利用、环境保护等方面的技术和工艺的研究;专用工艺设备、生产过程、机械化、自动化的研究;产品标准及其检测方法的研究与制订;岩石矿物、矿产品及其制品的物理、化学性能的测试、研究。     

世界酒花近况

酒花是啤洒工业最主要原料之一,在国际市场上占有较重要的地位。在国际上,生产酒花并有统计的国家是中国、西德、美国、苏联、捷克、英国、南斯拉夫、东德、西班牙、波兰、日本、澳大利亚、法国、比利时、保加利亚、罗马尼亚、葡萄牙、匈牙利、加拿大、新西兰、阿根廷、奥地利、北朝鲜、南非、瑞士等二十五个国家。酒花年产量超过一万吨的有西德、美国、苏联、英国和捷克等五国。世界现有酒花面积一百三十多万亩。世界最大的酒花基地是西德的哈拉道和美国的华盛顿。这两个基地的面积各占该国酒花总面积的70%左右。世界酒花的平均产量很不     

现代印刷的发展及应用

一、印刷与印刷品在日常生活中,人们所看到的或用到的报纸、杂志、期刊、地图、招贴、海报、广告、商标、信封、信笺、名片、请柬、信用卡、钞票、贺卡、台历、挂历、乃至包装纸、罐头盒、牙膏管、花色衣料、装饰壁纸、高级电路板等等,都属于印刷品的范畴。事实上,现代...     

果汁冷冻浓缩中生物冰核的成冰作用及初步应用

介绍了冰核细菌促进成冰的机制,并结合国外有关报道和我们的研究结果,论述了冰核细菌在食品冷冻浓缩中导致冰晶形成的结构、冷冻效率、应用前的预处理及食用级冰核细菌在果汁中的应用情况,最后展望了未来的研究方向。     

冰核细菌及其在食品工业中的应用

冰核细菌是一类在较低温度(-2.5～-5)℃下具有很强冰核活性的细菌,目前在植物冻害防治、促冻杀虫、人工降雪、食品冷冻浓缩等领域已成为研究热点。本文介绍了冰核细菌的成冰机制和影响因素,以及在食品工业中的应用,井对未来冰核细菌的研究趋势作一展望。     

Effects of ice-nucleation active bacteria on the freezing of some model food systems

Cells of ice-nucleation active (INA) bacteria, Pseudomonas syringae and Erwinia herbicola , were cultured at 18°C with media of nutrient broth and/or yeast extract and harvested at late log phase for maximum ice nucleation activity. These cells were able to nucleate water to freeze at temperatures as high as −2°C. They were incorporated into model food systems, including sugar, protein solutions and oil/water suspensions, representing all major components of foods, to investigate their effects on freezing. The nucleation temperatures of all the treated models were significantly raised by between 3.0 and 5.9°C compared with controls when the freezer temperature was set at −6 to −7°C. The application of the INA cells also caused freezing of certain model solutions at −6°C, such as sucrose solution (10%), which did not freeze at the same conditions without INA bacterial cells. Additions of INA cells also shortened the total freezing time of the model systems by between 20 and 38%. These results suggest that with the application of bacterial ice nucleation, some current food freezing processes may be modified to operate at higher subzero temperatures to provide guaranteed freezing, energy savings and improvement of efficiency and product quality.     

Freeze concentration of fruit juices

Concentration of aqueous foods such as fruit juices, milk, beer, wine, coffee, and tea, is a major unit operation in the food industry. Technically feasible processes that are commercially available for the concentration of liquid foods include evaporation, freeze concentration, reverse osmosis, and ultrafiltration. Evaporation is considered to be the most economical and most widely used method of concentration. However, it is not suited for food products with very delicate flavors. Commercial processes for the concentration of such products by membrane separation techniques are not yet available. As compared to the conventional evaporation processes, concentration by freezing is potentially a superior and economic process for aroma-rich liquid foods. In the past, the process, however, was seldom used because of the investment cost and the considerable loss of concentrate in the withdrawn ice, and hence, the quality. Recent technological developments have minimized these two drawbacks associated with the earlier freeze concentration processes. In the coming decade, freeze concentration is seen as a potentially attractive method for the concentration of aroma-rich liquid foods, including fruit juices, coffee, tea, and selected alcoholic beverages. In this article, several aspects of the theoretical considerations behind freeze concentration of fruit juices, the development of new and cheaper designs, and commercially available freeze concentration processes are reviewed. The economics of the process and its application to several other areas of the food industry are also discussed.     

Control of ice crystal nucleation and growth during the food freezing process

Freezing can maintain a low-temperature environment inside food, reducing water activity and preventing microorganism growth. However, when ice crystals are large, present in high amounts, and/or irregularly distributed, irreversible damage to food can occur. Therefore, ice growth is a vital parameter that needs to be controlled during frozen food processing and storage. In this review, ice growth theory and control are described. Macroscopic heat and mass transfer processes, the relationship between the growth of ice crystals and macroscopic heat transfer factors, and nucleation theory are reviewed based on the reported theoretical and experimental approaches. The issues addressed include how heat transfer occurs inside samples, variations in thermal properties with temperature, boundary conditions, and the functional relationship between ice crystal growth and freezing parameters. Quick freezing (e.g., cryogenic freezing) and unavoidable temperature fluctuations (e.g., multiple freeze–thaw cycles) are both taken into consideration. The approaches for controlling ice crystal growth based on the ice morphology and content are discussed. The characteristics and initial mechanisms of ice growth inhibitors (e.g., antifreeze proteins (AFPs), polysaccharides, and phenols) and ice nucleation agents (INAs) are complex, especially when considering their molecular structures, the ice-binding interface, and the dose. Although the market share for nonthermal processing technology is low, there will be more work on freezing technologies and their theoretical basis. Superchilling technology (partial freezing) is also mentioned here.     

新技术在食品冷冻过程中的应用

文中对超声冷冻技术、高压冷冻技术、冰核活性细菌和冰核活性蛋白及抗冻蛋白在食品冷冻过程中的应用作一介绍。     

冰核活性细菌Xanthomonas ampelina TS206的两种固定化方法的比较

冰核活性细菌固定化在食品冷冻浓缩中具有重要意义,冰核活性和抗渗漏能力是衡量其性能的两个重要技术指标.研究采用共固定化和海藻酸盐直接固定化两种方法,建立了冰核活性细菌Xanthomonas ampelina TS206的包埋技术.结果表明包埋量对冰核活性有较大影响,利用海藻酸盐直接固定化冰核活性较高,但渗漏量较大;利用共固定化冰核活性较低,但渗漏量很低.两种固定化方法的凝胶珠添加量与综合评分相关不大;海藻酸盐固定化综合评分与固化时间正相关,共固定化综合评分与固化时间略呈负相关.     

Freezing of meat and aquatic food: Underlying mechanisms and implications on protein oxidation

Over the recent decades,protein oxidation in muscle foods has gained increasing research interests as it is known that protein oxidation can affect eating quality and nutritional value of meat and aquatic products. Protein oxidation occurs during freezing/thawing and frozen storage of muscle foods, leading to irreversible physicochemical changes and impaired quality traits. Controlling oxidative damage to muscle foods during such technological processes requires a deeper understanding of the mechanisms of freezing-induced protein oxidation. This review focus on key physicochemical factors in freezing/thawing and frozen storage of muscle foods, such as formation of ice crystals, freeze concentrating and macromolecular crowding effect, instability of proteins at the ice–water interface, freezer burn, lipid oxidation, and so on. Possible relationships between these physicochemical factors and protein oxidation are thoroughly discussed. In addition, the occurrence of protein oxidation, the impact on eating quality and nutrition, and controlling methods are also briefly reviewed. This review will shed light on the complicated mechanism of protein oxidation in frozen muscle foods.     

植物抽取物对冰核活性细菌表达冰核活性蛋白的影响

植物提取物对于冰核活性细菌表达冰核活性蛋白具有明显的促进作用。通过添加适量的芥菜籽热水抽取物培养冰核活性细菌 (XanthomonasampelinaTS2 0 6) ,细菌的冰核活性比原来提高了 37.5 %,菌体的生物量提高了 36.2 %。芥菜籽抽提物作为一种效应物分子激活启动子 ,在冰核蛋白基因的表达中起到了重要作用 ,从而显著地提高了细菌高水平表达冰核活性蛋白的能力。     

Bacterial Extracellular Ice Nucleator Effects on Freezing of Foods

Extracellular ice nucleators (ECINs) were incorporated into foods and subjected to subzero freezing. Time-temperature profiles, ice-formation patterns and textures were examined by thermocouple, microscopy and texture analyzer. Onset temperatures (initial freezing), enthalpies and freezing rates were measured by DSC. Addition of ECINs to liquid foods elevated ice nucleation temperatures and promoted freezing. Solid or semisolid products frozen with ECINs resulted in a fiber-like texture. These effects were more apparent at –10°C or higher. Differential scanning calorimetry revealed onset temperatures were increased 11°C by addition of ECINs, but length of time to complete the phase transition was extended at constant cooling rates. Results indicated that ECINs can be used instead of whole bacterial cells for efficient freezing and textural modification.