Variation in nutrient composition of Australian retail potatoes over a 12-month period

‘Pontiac’, ‘Sebago’ and potatoes marketed under the general name of New potatoes were purchased from retail outlets in Sydney, Australia every 2 weeks over a 12-month period during 1982–83 to determine the change in composition over a season. Data are presented for water, vitamin C, starch, sugars (fructose, glucose and sucrose), dietary fibre, protein, fat, organic acids (malic, citric and oxalic acids), ash, carotenes, thiamin, riboflavin, niacin, potassium, sodium, calcium, magnesium, iron and zinc levels, edible weight and energy content. The level of vitamin C varied throughout the year from 10 to 23 mg 100 g^?1 for ‘Pontiac’, 14 to 29 mg 100 g^?1 for ‘Sebago’ and 16 to 32 mg 100 g^?1 for New potatoes with the lowest values occurring in August to September (late winter to early spring) and the highest values in December to January (mid summer). Substantial variations also occurred in the water content, which was higher, and the level of starch and hence energy content, which was lower, during the cooler months of the year. Smaller changes were noted for niacin and thiamin which were lower and sugars which were higher during the winter period.     

Nutrients in Wild and Farmed Fish and Shellfish

Wild and cultivated channel catfish, rainbow trout, coho salmon, red swamp crayfish, white river crayfish and Eastern oysters were analyzed raw and cooked for proximate composition and ten vitamins. Cultivated catfish had 5 and salmon 2 1/2 times more fat than their wild counterparts. In all other species wild and cultivated samples had similar nutrient content. Cholesterol was independent of fat content and similar in wild and cultivated samples. Vitamin B12 in 100g met or exceeded the 1989 Recommended Dietary Allowance (RDA) for adults of 2 μg/day in all species. Other B vitamines seldom exceeded 10% of the RDA except for niacin in finfish. Vitamin A, ascorbic acid and folic acid levels were negligible.     

乳清蛋白粉营养成分分析研究

目的分析不同批次乳清蛋白粉蛋白、脂肪、乳糖、维生素、矿物质及其他功能性营养素的含量及波动情况。方法依照国标方法对乳清蛋白粉营养成分进行检测,并对检测数据进行汇总,分析不同批次间乳清蛋白粉营养素指标的波动范围及相对标准偏差。结果不同批次间乳清蛋白粉营养素波动不大,部分维生素(维生素B12、叶酸、泛酸、维生素C)、矿物质(锌、镁)、功能性营养成分(α-亚麻酸、胆碱、左旋肉碱)相对标准偏差在15%以上,波动较大。结论乳清蛋白粉营养成分含量整体比较稳定。     

可食性蛋白质作为营养物质运送载体的研究概况

可食性蛋白质具有较高的营养价值和公认的安全性,还有很多可用于营养物质包埋的结构功能特性,用它作为营养物质的运送载体具有诱人的前景。本文介绍了作为载体的几种主要可食性蛋白质及理化性质,载体形式和在营养物质运送发展中的应用。说明利用可食性蛋白质独特的性质开发出的凝胶、微球、纳米粒等运送系统可以对营养物质进行保护,是包埋和运送营养物质的理想材料。     

铁皮石斛花营养成分分析

目的 明确铁皮石斛花的营养价值, 促进其开发利用。方法 以烘干后的铁皮石斛花为原料, 采用国家标准方法测定铁皮石斛花的蛋白质、可溶性糖、多糖、游离氨基酸总含量, 应用高效液相色谱法、气相色谱-质谱法、液相色谱-质谱法和电感耦合等离子体发射光谱法检测游离氨基酸、可溶性糖、中长链脂肪酸、维生素和矿物质含量。结果 铁皮石斛花中游离氨基酸和可溶性糖含量分别为(2.37±0.07)%和(45.74±1.77)%, 从铁皮石斛花中检测到16种氨基酸、13种可溶性糖、12种矿质元素、8种脂肪酸、10种B族维生素以及维生素E、维生素C和维生素K1。结论 铁皮石斛花富含亚油酸 (16.09±0.45) mg/g、VB4(530.78±29.37) μg/g、VC(201.28±0.01) μg/g和K(18289.63±1398.96) mg/kg等多种营养物质, 可作为功能食品的开发原料。     

鳄鱼肉与其他肉类营养成分的比较分析

为了进一步挖掘鳄鱼肉的营养价值,以鳄鱼肉、猪肉、牛肉、鸡肉、羊肉、河虾肉和鲫鱼肉为研究对象,采用国家标准检测方法,分析和测定其含有的主要营养成分并进行营养评价.结果表明:与其他肉类相比,鳄鱼肉中磷含量最高;鳄鱼肉中钙含量显著高于其他畜禽肉(P<0.05),是一种优质补钙食品,鳄鱼肉中水溶性维生素含量最高,鲜味氨基酸含量...     

抗性淀粉及其纳米颗粒的制备与应用

淀粉是人类饮食中必不可少的能量来源。抗性淀粉是在小肠中不能被消化的淀粉, 在结肠中被微生物发酵, 形成短链脂肪酸, 对机体健康有许多健康益处, 例如平衡肠道菌群、预防肠道疾病、改善肥胖等。随着需求量的增加, 抗性淀粉及其纳米颗粒的制备越来越受到人们的关注, 越来越多的加工技术用来制备抗性淀粉纳米颗粒。不同的加工技术可以改变淀粉的颗粒形态和晶体结构等物理特征, 增加抗性淀粉的含量, 更能抵抗消化酶的酶解作用。抗性淀粉及其纳米颗粒已被广泛应用于食品及递送体系的构建, 作为一种新兴的添加剂具有良好的市场前景和发展潜力。本文将重点介绍抗性淀粉及其纳米颗粒的分类、制备方法、健康益处以及在食品等领域中的具体应用, 对产业现状进行了分析并提出展望, 为抗性淀粉及其纳米颗粒的制备与应用提供参考。     

In vitro activity of vitamins, flavonoids, and natural phenolic antioxidants against the oxidative deterioration of oil-based systems

It is well-known, that lipid antioxidants can retard the oxidative rancidity of foods caused by atmospheric oxidation, and thus protect oils, fats, and fat-soluble components from their quality degradation. In the last few years, much emphasis has been put on the promotion and use of natural antioxidants, commonly occurring in many fruits and vegetables and thereby produced from various natural extracts. This review gives a summary of previously reported work together with more recent trends in the field of natural antioxidants. Focus is given on the mechanism of actions and the inhibitory effect of certain vitamins against the oxidative degradation of oil-based systems. Moreover, the use of natural phenolics (flavonoids, olive-oil penolics, herb extracts etc.) as antioxidants in numerous lipid food applications is discussed.     

食品添加剂中维生素A、D和E的检测方法研究

食品添加剂中脂溶性维生素A、D和E在皂化过程中与脂肪分离，经石油醚萃取后，用高压液相色谱法．由紫外检测器一次性测定3种物质。维生素A、D和E的回收率分别为94．7％．101．7％、96．7％．102．3％、97．5％．103．5％，精密度分别为2．79％、4．16％和1.68％。结果表明，该方法的主要特点为操作快捷、精密度高、重现性好。     

母乳中宏量营养成分含量与新生儿相关因素的分析

实验采用队列研究的方法,收集华北地区和中南地区共四个城市乳母分娩后3~5 d、12~14 d、1月、2月、3月、4月和6月的母乳,测定中国现阶段健康乳母不同泌乳阶段母乳中脂肪、总蛋白质、乳糖、干物质、总能量和真蛋白质等宏量营养成分的动态变化,同时研究分娩方式和婴儿性别与各宏量营养成分之间的关系。母乳中宏量营养成分含量的测定采用MIRIS HMA母乳分析仪。结果表明初乳中顺产组的母乳中总蛋白质和真蛋白质含量显著高于剖宫产组的(p<0.05),过渡乳中脂肪、总蛋白质、乳糖、干物质、总能量和真蛋白质等宏量营养成分含量在顺产、剖宫产两组间均无显著性差异(p>0.05),成熟乳(6月时)中剖宫产组的母乳中乳糖和干物质含量显著高于顺产组的(p<0.05)。此外,初乳和过渡乳中脂肪、总蛋白质、乳糖、干物质、总能量和真蛋白质等宏量营养成分含量在男孩、女孩两组间均无显著性差异(p>0.05),但是成熟乳中女孩组3月时的母乳中脂肪和总能量含量,4月时的总蛋白质和真蛋白质含量显著高于男孩组的(p<0.05)。不同分娩方式及婴儿性别对母乳中宏量营养成分的含量有一定影响。      

Concentration of Selected Vitamins in Infant Milks Available in Spain

ABSTRACT: Vitamins A, E, and those of the B complex were determined in 59 standard and 11 specialized infant milks from the Spanish market. Water-soluble vitamin levels were lower than those declared by manufacturers in 50% of the standard infant milk products. Vitamin A ranged from 58.8 μg/100mL to 170.9 μ/100mL and vitamin E from 0.8 mg/100mL to 3.3 mg/100ml. Most of the samples had a higher vitamin A content than that stated by the manufacturer, and 13% and 42% of them exceeded the Spanish legislation and the ESPGAN recommendation levels respectively. Vitamin E levels were between 2 and 10 times higher than the minimum established by these organizations and in general were over the declared level.