食品中RS3含量与凝胶性的关系

测定了米线、粉丝、馒头、面包和红薯淀粉中RS3的含量,比较RS3含量与凝胶性的关系。米线中RS3为9.882%,绿豆粉丝为7.902%,水晶粉丝为10.449%,红薯粉丝为10.899%。在冷藏过程中,馒头和面包样品随着RS3含量的增加,凝胶的硬度分别从1031.45g和349.87g增加到4820.10g和851.45g,弹性分别从0.96和0.923下降到0.858和0.9075。红薯淀粉随着加热-冷却处理次数的增加,RS3含量从2.55%增加到6.95%,凝胶的硬度从82.198g增加到497.461g,弹性从0.988下降到0.923。因此,随着RS3含量的增加,凝胶的硬度均显著增加,而弹性变化不大。      

发酵性食品中的氨基甲酸乙酯含量调研

采用SLE(固相支持液/液萃取)结合GC-MS法测定酸奶、酱油、葡萄酒、黄酒及干酪、腐乳中的氨幕甲酸乙酯含量,检测结果显示,黄酒、腐乳中氨基甲酸乙酯含量较高,其次是葡萄酒和酱油,发酵性乳制品和豆豉中均未检出氨基甲酸乙酯.     

花生凝胶食品的研制

本文依据花生蛋白质在一定条件沉凝的特性,采用CaCl2进行了花生凝胶食品的研制。结果表明,产品具有花生特有的风味和良好的烹饪加工性能,维生素E、蛋白质、脂肪收得率分别为81．2％、92．3％和82．1％。     

食品中甲醛的含量与控制

在食品加工过程中,可以通过采取不使用甲醛作为添加剂或甲醛含量高的物质做原料;采用合理的加工工艺;不使用甲醛为材料制造的树脂作为食品包装材料等措施,来有效地控制食品中的甲醛含量。      

食品中吊白块含量的测定

吊白块，学名甲醛合次硫酸氢钠（CH２（OH）SO２Na·２H２O），是工业用增白剂，主要用于染布漂白。若作为食品脱色剂使用，会使食品中残留有害的甲醛，人体摄入甲醛后，可引起食欲减退、厌食、体重减轻、衰弱、失眠等症状。为此，国家早已明文规定，禁止吊白块在食品中使用。但目前在市场上发现，个别小生产者或个体户，他们唯利是图，不惜损害消费者的身体健康，为了吸引消费者，使馒头或粉丝等食品的外观色白漂亮，竟然在这些食品中使用了吊白块。为了维护消费者的利益，保障人民群众的身体健康，严厉打击食品领域的违法行为，有必要…     

淀粉基凝胶在食品3D 打印中的研究进展

食品3D 打印技术是一种在食品领域新兴的、由计算机辅助软件控制的智能化快速成型技术。因其具有高效、便捷、个性化定制的特点,在食品加工领域中有较大的发展潜力。淀粉作为一种可再生的天然高分子,具有无毒害、经济环保、资源丰富的优点,是3D 打印优质的食品级油墨。近年来,随着食品3D 打印技术的不断发展,如何提高天然食用凝胶的可打印性成为研究热点。为更好地了解淀粉基凝胶3D 打印的研究进展,该文从3D 打印技术原理、淀粉基原料3D 打印特性、影响淀粉基凝胶3D 打印效果的因素、淀粉基凝胶3D 打印的应用现状以及面临的挑战等方面进行综述,以期为淀粉基凝胶在食品3D 打印中的发展和应用提供参考。     

0~36月龄婴幼儿配方食品及婴幼儿辅助食品中糖含量分析

目的 了解我国市售婴幼儿配方食品（婴儿配方食品、较大婴儿配方食品和幼儿配方食品）及婴幼儿辅助食品（婴幼儿谷类辅助食品和罐装辅助食品）中葡萄糖、半乳糖、果糖、乳糖、蔗糖和麦芽糖的含量,为婴幼儿配方食品及婴幼儿辅助食品相关的食品安全标准管理提供数据支持。方法 根据随机抽样原则,采集国内市场常见的婴幼儿配方食品及婴幼儿辅助食品83例,涵盖婴幼儿配方食品、婴幼儿谷类辅助食品和婴幼儿罐装食品等,利用离子色谱-脉冲安培法对葡萄糖、半乳糖、果糖、乳糖、蔗糖和麦芽糖进行含量检测,并对检测结果进行分析。结果 婴幼儿配方食品中总糖含量的中位数为433.43～476.99 g/kg,其中乳糖占总糖的比均高于95%,乳糖含量由高至低分别为婴儿配方食品、较大婴儿配方食品和幼儿配方食品。婴幼儿谷类辅助食品中总糖检出率为36.8%,含量中位数为0～28.35 g/kg,其乳糖和蔗糖的中位数较高,为84.30和70.17 g/kg,而蔗糖在饼干第三四分位数（Q3）的含量较高,为53.43 g/kg。国产和原装进口配方食品的添加糖含量进行比对,差异没有统计学意义（P>0.05）。结论 我国市售的婴幼儿配方食品中乳...     

大米及其制品中的RS3

测定了英国市场上销售的Basmati(白米,糙米)(长粒米),泰国香米(长粒米),日本大米(短粒米)样品中RS3的含量,比较长粒米和短粒米在熟化过程的稳定性以及不同米制品中含量的差异.结果表明,短粒大米RS3含量高于长粒大米;熟化过程对RS3含量的影响巨大,其中白米米粉在熟化过程中RS3含量下降的程度低于糙米米粉,长粒米米粉、短粒米米粉在熟化过程中RS3含量下降的程度差异不大;保鲜米饭与同品种大米制作熟化大米粉的RS3含量基本相当.     

黄原胶与魔芋胶的协效凝胶性研究

黄原胶与魔芋胶均为非凝胶多糖,但二者在一定条件下共混可以得到凝胶。当黄原胶与魔芋胶以0.7/0.3的配比共混,多糖总浓度为1%时,二者的协效凝胶性最强,即凝胶强度最大,同时对制备温度和体系盐离子浓度对多糖共混凝胶性的影响作了初步研究,研究表明,当制备温度80℃,盐离子浓度为0.2mol/L,凝胶强度最大。     

食品成分对淀粉凝胶力学性能的影响

淀粉凝胶的力学性能因糖、无机盐、酸碱、单甘酯等的加入用来改善食品风味和口感的物质而发生变化。这种变化是由于添加物质与淀粉大分子发生作用或是添加物质对淀粉大分子之间的相互作用的产生影响造成的。该研究结果对于生产既具有一定风味又不失良好力学性能的淀粉凝胶类产品提供了必要的依据。     

Saponin content of some Nigerian foods

Saponins have been extracted and purified from millet (Pennisetum typhoideum), beans (Phaseolus vulgaris), guinea-corn (Sorghum vulgare) and groundnut (Arachis hypogaea). Beans were found to contain a considerable amount of saponin—245.0 mg kg^?1, while millet, guinea-corn and groundnut contained 194.7, 72.7 and 48.8 mg kg^?1 dry weight basis respectively.     

Saponin content of food plants and some prepared foods

Quantitative thin layer chromatography was used to estimate the saponin content of 20 common food plants and also of foods prepared from some of them. The food plants found to be richest in saponins were chickpeas (Cicer arietinum), soya beans (Glycine max), lucerne (alfalfa) sprouts (Medicago sativa) and varieties of Phaseolus vulgaris (navy beans, haricot beans, kidney beans). Saponins were not destroyed by processing or cooking. They were present in falafels (prepared from chickpeas), canned baked beans, canned broad beans and protein isolate from faba beans. However, the saponin content of a fermented soya bean product (tempe) was only half that of whole soya beans. Guar meal (Cyamopsis tetragonolobus) contains saponins but only a trace could be detected in samples of guar gum.     

Relationship between the antioxidant properties and the phenolic and flavonoid content in traditional balsamic vinegar

The antioxidant properties of traditional balsamic vinegar as regards its phenolic and flavonoid content comparing it to selected vinegars and red wines have been investigated. The polyphenols were separated from interfering compounds utilizing C18 columns. The polyphenolic content was determined utilizing both Folin–Ciocalteu and peroxidase assays. The antioxidant capacity was quantified using both ABTS and FRAP assays. The results show that traditional balsamic vinegar has lower antioxidant activity and phenolic and flavonoid content than Nero d’Avola but higher than the other tested products. The antioxidant capacity of wines and vinegars is highly correlated with their phenolic content, measured by peroxidase assay and it is also highly correlated with their flavonoid content while in traditional balsamic vinegar and balsamic vinegar this correlation diminishes. The study describes a simple and fast method of separating from other compounds and of measuring polyphenols in the analysis of red wines and vinegars with complex composition such as traditional balsamic vinegar.     

Multi-element determination in some foods and beverages using silica gel modified with 1-phenylthiosemicarbazide

ABSTRACT

1-Phenylthiosemicarbazide bonded modified silica gel (PTC-SG) was synthesised and characterised by FTIR, SEM and elemental analysis for a novel separation/preconcentration of multiple elements based on solid phase extraction. The analytical parameters including pH of solutions, amounts of PTC-SG, flow rates of sample, eluent type and sample volume were optimised. The adsorption capacities of PTC-SG were found to be 7.9, 6.4, 6.3, 8.3, 7.2, 8.9 and 6.6 mg/g for Cu(II), Cd(II), Pb(II), Co(II), Cr(III), Ni(II) and Mn(II), respectively. The limit of detection (LOD) was calculated as 3x the standard deviation(s) of the reagent blank (k = 3, N = 21) and the LOD values were obtained to be 0.98 µg L^?1 (Cu), 0.65 µg L^?1 (Cd), 0.57 µg L^?1 (Pb), 1.12 µg L^?1 (Co), 1.82 µL^?1 (Cr), 1.67 µg L^?1 (Ni) and 0.55 µg L^?1 (Mn). Certified reference materials were used to test the validation of the present method. The new solid phase extraction method was successfully applied to determination of the amount of multiple elements in food and beverage samples.     

Phytate content of some foods from plant origin from Vietnam and Hungary

For the estimation of phytate-ion the iron content of FeIII-phytate complex was determined by spectrophotometry with o-phenanthroline. In most cases phytate-phosphorus was also evaluated. In different food samples iron to phosphorus ratio in phytate generally deviated significantly from the theoretical 1.20 value. Wheat flour products, maize, rice, beans, peas, lentil and soy from Vietnam and Hungary, furthermore several bakery products from Hungary and some imported soy products were analysed for phytate content. The effect of heat and fermentation on phytate content was also checked in breads and other foods. It was concluded that the processes often used in food industry, namely fermentation and thermal load, have relatively slight effect on the phytate content of plant foods. Cooking losses for phytates ranged 1-60% in cereals and legumes according to the usual kitchen technique in Vietnam.     

Fluoride content of some common South Indian foods and their contribution to fluorosis

Fluoride contents of 98 food items commonly used in South India were determined with special reference to the feeding habits of remote rural populations in 41 villages of Anantapur District, Andhra Pradesh, India, where dental and skeletal fluorosis is endemic. Fluoride up to 4.5 mg kg^?1 was found in irrigation and drinking water supplies. Thirty-two locally grown food items had generally higher fluoride contents (ranging jiom 0.2 to 11.0 mg kg^?1) with the notable exception of coconut water where even traces of fluoride could not be detected. The combined daily intake of fluoride jiom food and drinking water in the local population was found to range jiom 2.2 mg to 7-3 mg (0.05–0.32 mg kg^?1 BW). The role played by food composition, cooking habits of the local population, general poverty and illiteracy in contributing to the prevalence of fluorosis in schoolchildren in the age group 6–18 years (even in areas with drinking water supplies within the permissible levels as per WHO standards) is discussed.     

Aluminium content of some foods and food products in the USA, with aluminium food additives.

The primary objective was to determine the aluminium (Al) content of selected foods and food products in the USA which contain Al as an approved food additive. Intake of Al from the labeled serving size of each food product was calculated. The samples were acid or base digested and analysed for Al using electrothermal atomic absorption spectrometry. Quality control (QC) samples, with matrices matching the samples, were generated and used to verify the Al determinations. Food product Al content ranged from <1-27,000 mg kg(-1). Cheese in a serving of frozen pizzas had up to 14 mg of Al, from basic sodium aluminium phosphate; whereas the same amount of cheese in a ready-to-eat restaurant pizza provided 0.03-0.09 mg. Many single serving packets of non-dairy creamer had approximately 50-600 mg Al kg(-1) as sodium aluminosilicate, providing up to 1.5 mg Al per serving. Many single serving packets of salt also had sodium aluminosilicate as an additive, but the Al content was less than in single-serving non-dairy creamer packets. Acidic sodium aluminium phosphate was present in many food products, pancakes and waffles. Baking powder, some pancake/waffle mixes and frozen products, and ready-to-eat pancakes provided the most Al of the foods tested; up to 180 mg/serving. Many products provide a significant amount of Al compared to the typical intake of 3-12 mg/day reported from dietary Al studies conducted in many countries.     

Aluminium content of foods and diets

Literature data on the aluminium content of individual foods have been compiled, summarized and presented by food groups. The contribution of aluminium from food preparation and cooking utensils and from food additives is discussed. Literature data on the daily intake of aluminium are summarized, and the contribution of food groups to daily aluminium intake is estimated. The major sources of dietary aluminium include several with aluminium additives (grain products, processed cheese and salt) and several that are naturally high in aluminium (tea, herbs and spices). The aluminium that may migrate from aluminium utensils is probably not a major or consistent source of this element. Daily intakes of aluminium, as reported prior to 1980, were 18-36 mg per day. More recent data, which are probably more accurate, indicate intakes of 9 mg per day for teenage and adult females and 12-14 mg per day for teenage and adult males.     

Relationship between lutein and mycotoxin content in durum wheat

Levels of lutein and a number of mycotoxins were determined in seven varieties of durum wheat (Triticum durum) and two varieties of common wheat (Triticum aestivum) in order to explore possible relationships amongst these components. Durum wheat cultivars always showed both higher lutein and mycotoxin contents than common wheat cultivars. The mycotoxins detected in both common and durum wheat cultivars were produced by the genera Fusarium, Claviceps, Alternaria and Aspergillus. Fusarium was the major producer of mycotoxins (26 mycotoxins) followed by Claviceps (14 mycotoxins), which was present only in some cultivars such as Chevalier (common wheat), Lupidur and Selyemdur (both durum wheat), Alternaria (six mycotoxins) and Aspergillus (three mycotoxins). Positive correlations between the levels of lutein and mycotoxins in durum wheat cultivars were found for the following mycotoxins: deoxynivalenol (DON), its derivative DON-3-glucoside, moniliformin, culmorin and its derivatives (5-hydroxyculmorin and 15-hydroxyculmorin).