Fortification of Bread with Potato Products

The supplementarity of potatoes for cereal proteins which are poor in lysine is attested by the historical fact that bread and potatoes have sustained people through adverse nutritional circumstances such as the two World Wars. This review summarizes the state of the art of breadmaking with potato products. Traditionally used bread additives such as cooked potatoes, potato starch, potato flour, potato flakes, potato water, etc. as well as unconventional ones such as potato protein concentrates recovered from potato processing plant wastes are discussed.     

The status of trace elements in staple foods from the former Federal Republic of Germany

In representative samples of bread cereals and cereal products from the former Federal Republik of Germany (FRG) the status of 11 trace elements was analysed in 1989. It is demonstrated that the results are quite representative for the former FRG as compared with results published in the previous 15 years. The sampling technique for staple foods is explained. A number of certified standard reference materials were used to validate the analytical methods employed.     

Recent Developments in Application of Stable Isotope and Multi-element Analysis on Geographical Origin Traceability of Cereal Grains

With the development of cereal grain market and convenient transportation of food all over the world, the potential for distribution of mislabeled products increases accordingly, highlighting the need of consumers pursuing for high-quality cereal grains with a clear geographical origin identity. Appropriate analytical methods to ensure a fair competition among producers and to protect consumers against fraud are extremely required. Currently, stable isotope ratio analysis and multi-element analysis gradually become the promising approaches for cereal grain traceability. In recent years, a growing number of research papers have been published on tracing cereal grains by stable isotope ratio and multi-element analysis combining with other instruments. In these reports, the global variety of stable isotope compositions has been investigated, including light elements such as C, N, H, O, and S, and heavy isotopes variation such as Sr and B; in addition, more than 50 elements were applied in the geographical origin analysis of cereal grain and favorable results were obtained. In the present paper, an overview about geographical origin traceability of cereal grain by stable isotope ratio analysis and multi-element analysis is provided.     

微波消解-ICP-MS法测定红薯中18种元素

建立电感耦合等离子体质谱法和在线内标法测定3个红薯品种(黄心红薯、白心红薯、紫红薯)生红薯、熟红薯、红薯皮及表面土壤中铅(Pb)、砷(As)、镉(Cd)、汞(Hg)、铬(Cr)、钴(Co)、铝(Al)7种重金属元素及钠(Na)、钾(K)、钙(Ca)、锌(Zn)、硒(Se)、镁(Mg)、铁(Fe)、锰(Mn)、镍(Ni)...     

甘薯茎叶生理功能与其加工利用

甘薯是我国大宗农产品, 其茎叶常作为饲料或者直接废弃。目前研究表明, 甘薯茎叶含有丰富的营养成分, 包括糖、蛋白质、维生素、钾、钙、铁等微量元素。此外还含有黄酮类化合物、绿原酸、多糖等多种生理活性成分, 具有多种医疗保健功能, 如防癌、降血糖、降血脂、抑菌防腐等功效。因此, 对甘薯茎叶资源进行开发和利用, 不但可以提高农业附加值, 还能为消费者提供健康食品。本文详细论述了甘薯茎叶的活性成分及其生理功能, 并简要介绍了甘薯茎叶的加工现状, 提出未来研究和发展趋势, 为更好利用甘薯资源提供参考。     

Influence of salts on starch degradation: Part I – sodium chloride

To reduce the amount of salt in cereal‐based products without changing their properties, it is necessary to understand the role of salt in the product. Native wx maize, cassava or potato starch were mixed with sodium chloride (NaCl; 0–4% dry weight basis; moisture adjusted to 20% wet weight basis; wwb) and were heated at 230°C for 45 min. Presence of salt enhanced colour formation proportionally to its concentration. Microscopic observations, wide angle X‐ray, DSC and intrinsic viscosity data all suggested that the starch granule and the starch polymer were degraded by such heat treatment. Presence of NaCl enhanced the degradation proportionally to its concentration. This degradation might lead to the formation of smaller molecules which potentially could then caramelise during the heat treatment. This mechanism may explain the impact of salt on colour formation in cereal‐based products.     

几种物料挤压加工过程中的丙烯酰胺形成规律研究

研究了玉米粉、小麦粉、马铃薯粉、小米粉、豌豆粉等几种谷物与杂豆粉经过挤压加工后的丙烯酰胺含量,结果表明马铃薯-小麦混合粉挤出物中丙烯酰胺的含量最高。并以马铃薯-小麦混合粉为基础原料,研究了添加大豆脱脂蛋白、淀粉、蔗糖等对挤压加工过程中丙烯酰胺形成的影响。结果表明大豆脱脂蛋白、淀粉、蔗糖等组分对马铃薯-小麦混合粉挤出物的丙烯酰胺含量均有显著影响(p<0.05)。其中,添加大豆脱脂蛋白8%、淀粉5%、蔗糖12%时,挤压产品中丙烯酰胺含量均达最大值。     

凉粉草胶与不同淀粉混合体系糊化和质构性质的研究

凉粉草胶(MBG)与淀粉作用可以形成凝胶。为比较不同淀粉与MBG混合体系糊化和凝胶性质的差异,选取玉米等八种常见淀粉,利用Brabender糊化仪、质构仪、对MBG与不同淀粉混合体系的糊化和质构性质进行了研究。结果发现,MBG对谷类淀粉(大米、小麦、玉米)和豆类淀粉(绿豆、豌豆)的糊化性质的影响都比较显著,对薯类淀粉(木薯、马铃薯、甘薯)的不显著,但MBG与薯类淀粉混合体系的黏度远高于MBG与豆类和谷类淀粉的;MBG与大米淀粉形成的凝胶硬度最大,与马铃薯淀粉形成的凝胶硬度次之,与豌豆淀粉形成的凝胶硬度最小。淀粉与MBG之间相互作用的强弱可以从Brabender糊化曲线上的特征点值E-D来比较。     

COMPARATIVE ANALYSIS OF TRYPAN BLUE AGAR AND CONGO RED AGAR FOR THE ENUMERATION OF YEAST AND MOLD USING THE HGMF SYSTEM1

Enumeration of yeast and molds from 39 food samples, including 6 dairy products, 2 meat products, 5 cereal products, 9 fruits, 4 vegetables, 6 beverages, 4 spices, and 3 condiments on Trypan blue (at 1: 10,000 dilution) in potato dextrose agar (Trypan blue agar) was compared with Congo red (at 25:1,000,000 dilution) in potato dextrose agar (Congo red agar) using the hydrophobic grid-membrane filter (HGMF) technique of the ISO-GRID system. Yeast and mold grew well on both Trypan blue agar and Congo red agar, producing blue and red colonies, respectively, in the ISO-GRID system, when examined in incan-descent light. However, not all yeast and mold colonies grown on Congo red agar fluoresced under ultraviolet (UV) light (a recommended observation procedure). Thus, results indicated that Trypan blue agar observed in incandescent light is more convenient to use for enumerating yeast and mold in food samples.     

新疆引进红枣中微量元素和重金属含量的测定与聚类分析

为评价引进红枣果实元素的营养价值,以塔里木盆地50 种内地引进嫁接2 a后生红枣品种的成熟果实为试材,分别采用火焰原子吸收光谱法、石墨炉原子吸收光谱法和原子荧光光谱法测定Fe、Zn、Mn、Cu、Ca、Se 6 种有益元素和Cd、As、Hg、Pb 4 种有害元素的含量,并根据红枣中元素种类和含量的不同,采用SPSS 19.0软件欧氏距离法对红枣品种进行了聚类分析。结果表明：50 个红枣品种均含有丰富的微量元素,其中蛤蟆枣中Ca元素和Fe元素的含量最高,Se元素含量普遍较低。除了义乌大枣和蛤蟆枣红枣中Hg元素含量略高以外,其他供试红枣品种中Cd、Hg、As和Pb 4 种有害元素的含量均符合GB 2762-2012《食品中污染物限量》要求。结论：引进红枣品种果实中微量元素种类多、含量高,安全性高,研究结果可为红枣专属品种选育和药食同源产品开发提供科学依据。     

谷物膳食纤维在肉类加工制品中的应用与研究进展

传统肉制品存在脂肪含量高、蒸煮损失大等问题,影响肉制品的品质.添加有谷物膳食纤维的肉制品脂肪含量低、营养成分均衡、品质好,长时间食用该类肉制品可以显著降低多种慢性疾病的发生.近年来,谷物膳食纤维在肉制品中的应用得到国内外研究学者的广泛关注.该文综述了谷物膳食纤维对肉制品品质的影响和谷物膳食纤维在肉制品中应用的国内外研究...     

马铃薯淀粉凝胶形成及其品质影响因素研究进展

马铃薯淀粉黏度高、易糊化,淀粉糊稳定性及透明度高,被广泛应用于各类凝胶制品的加工中。温度、pH等环境因素以及盐类、多糖、蛋白质等食用成分对马铃薯淀粉的糊化特性及淀粉凝胶的回生特性、流变特性、微观结构等影响不同,进而影响马铃薯淀粉凝胶制品的品质。本文在分析马铃薯淀粉凝胶形成机制的基础上,综述了不同环境因素及食用成分对马铃薯淀粉凝胶品质特性的影响规律,揭示了不同食用成分与马铃薯淀粉分子之间的相互作用原理。旨在为高品质、高营养马铃薯淀粉凝胶及其制品的研究与工业化生产提供参考。     

Relation Between In Vitro Availability of Minerals and Food Composition: A Mathematical Model

A mathematical model was developed to describe the relative influence of phytic acid, dietary fiber components, oxalic acid, citric acid and ascorbic acid on in vitro availability of Ca, Mg, Fe, Cu and Zn. The model was based on a combination of interdependent Langmuir isotherms. Throughout a diverse set of food products (cereal products, fruits, vegetables and nuts), the mathematical model described and predicted in vitro availability of Ca, Mg, Fe and Zn well (r = 0.89, 0.87, 0.90 and 0.92 respectively). The model proved valuable in studying simultaneous effects of food components on in vitm availability of minerals and trace elements in foods. Therefore, the mathematical model should help relate in vitro simulations to in vivo experiments.     

Superheated steam processing of cereals and cereal products: A review

The concept of superheated steam (SS) was proposed over a century ago and has been widely studied as a drying method. SS processing of cereals and cereal products has been extensively studied in recent years for its advantages of higher drying rates above the inversion temperature, oxygen-free environment, energy conservation, and environmental protection. This review provides a brief introduction to the history, principles, and classification of SS. The applications of SS processing in the drying, enzymatic inactivation, sterilization, mycotoxin degradation, roasting, and cooking of cereals and cereal products are summarized and discussed. Moreover, the effects of SS processing on the physicochemical properties of cereals and the qualities of cereal foods are reviewed and discussed. The applications of SS for cereal processing and its effects on cereal properties have been extensively studied; however, issues such as the browning of cereal foods, thermal damage of starch, protein denaturation, and nutrition loss have not been comprehensively studied. Therefore, further studies are required to better understand the mechanism of the quality changes caused by SS processing and to expand the fields of application of SS in the cereal processing industry. This review enhances the understanding of SS processing and presents theoretical suggestions for promoting SS processing to improve the safety and quality of cereals and cereal products.     

Uptake of trace elements and PAHs by fruit and vegetables from contaminated soils

The aims of this study were to investigate the uptake of seven trace elements and five PAHs in crop plants in order to establish advice regarding consumption of fruit and vegetables grown in soils contaminated by trace elements and PAHs. In a field experiment, vegetables were grown in two contaminated soils and in a reference soil, whereas fruits were collected from uncontaminated and contaminated private gardens. The results showed elevated levels of several trace elements and PAHs in the vegetables from contaminated soil. Bioconcentration factors (BCF values), based on dry weight, were below 1, except for those of Cd in lettuce and carrot with peel from uncontaminated soil. In most cases, BCF values were decreasing with increasing concentrations in soil. From the heavily contaminated soil, BCF values for Pb in lettuce, potato, and carrot with peel were 0.001, 0.002, and 0.05, respectively, and those for benzo[a]pyrene were 0.004, 0.002, and 0.002, respectively. For most metals in most vegetables, linear regression showed good correlation between soil and crop concentrations. For PAHs, such good correlation was generally not found. The contents of contaminants in fruits were generally low and no correlation with the level of contamination in the soils was found.     

土豆中微量元素的质谱分析

对土豆样品采用HNO3+H2O2混合酸消解体系进行微波消解处理制样,用电感耦合等离子体质谱（ICP-MS）法同时测定土豆中Na、Mg、Al、P、K、Ca、Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Se、Pb共16种微量元素的含量。详细地研究了样品的前处理条件,选用Rh作内标元素校正基体效应和信号漂移,该方法对16种待测元素的检出限为0.005～0.236μg/L,通过添加标准进行加标回收,所有待测元素的回收率在92.20%～109.65%之间,相对标准偏差（RSD）均小于3.18%,结果准确可靠。该法可为土豆中微量元素的快速检测提供科学依据。      

Differentiation of potato cultivars experimentally cultivated based on their chemical composition and by applying linear discriminant analysis

Moisture, starch, amylose, fibre, proteins, ascorbic acid, total phenol compounds, acidity, pH, ash and mineral and trace elements were determined in 10 potato cultivars from Canary Islands experimentally cultivated. Six of the cultivars were also cultivated in two locations, to ascertain the impact of different soil types on the parameters measured. There were differences between cultivars in both, physicochemical parameters and mineral and trace elements analysed. There were significant differences in the mean values obtained for all the parameters considered, except for ascorbic acid, between both locations. Application of linear discriminant analysis allowed to classify the potato samples according to the cultivar, and according to growing location.     

Technologies for enhancement of bioactive components and potential health benefits of cereal and cereal-based foods: Research advances and application challenges

Cereal grains are a major source of human food and their production has steadily been increased during the last several decades to meet the demand of our increasing world population. The modernized society and the expansion of the cereal food industry created a need for highly efficient processing technologies, especially flour production. Earlier scientific research efforts have led to the invention of the modern steel roller mill, and the refined flour of wheat has become a basic component in most of cereal-based foods such as breads and pastries because of the unique functionality of wheat protein. On the other hand, epidemiological studies have found that consumption of whole cereal grains was health beneficial. The health benefit of whole cereal grain is attributed to the combined effects of micronutrients, phytochemicals, and dietary fibre, which are mainly located in the outer bran layer and the germ. However, the removal of bran and germ from cereal grains during polishing and milling results in refined flour and food products with lower bioactive compounds and dietary fibre contents than those from whole grain. Also, the level of bioactive compounds in cereal food is influenced by other food preparation procedures such as baking, cooking, extrusion, and puffing. Therefore, food scientists and nutritionists are searching for strategies and processing technologies to enhance the content and bioavailability of nutrients, bioactive compounds, and dietary fibre of cereal foods. The objective of this article was to review the research advances on technologies for the enhancement of bioactive compounds and dietary fibre contents of cereal and cereal-based foods. Bioactivities or biological effects of enhanced cereal and cereal-based foods are presented. Challenges facing the application of the proposed technologies in the food industry are also discussed.     

Elemental content of commercial ‘ready to-feed’ poultry and fish based infant foods in the UK

The study reported herein was conducted in order to establish the concentration of 20 essential and non-essential elements in a representative range of commercial infant foods in the UK targeted for infants aged between 6–12 months. The primary objective of this study was to examine the nutritive values and safety of such complementary infant foods on the UK market in relation to dietary and safety guidelines. Quantitative analyses were conducted on eight different products representing four popular brands (poultry and fish based) of ready to-feed infant foods currently on sale in the UK. Six essential elements, namely: calcium, iron, magnesium, potassium, sodium and zinc were determined by ICP-OES. The concentrations of six essential trace elements (selenium, molybdenum, cobalt, copper, chromium, manganese) and eight non-essential, potentially toxic, elements (arsenic, barium, nickel, cadmium, antimony, lead, mercury, aluminium) were determined by ICP-MS due to the higher sensitivity required. The total daily intakes of essential and trace elements from the consumption of such products were then estimated, based on the results of this study, and were referenced to the Recommended Nutrient Intake (RNI) values and safety guidelines for 6–9 months old children. Based on these comparisons the concentration of essential, except for potassium, and trace elements were found to be inadequate in meeting the RNI. In terms of the risk of exposure to toxicity, the concentration of toxic elements in ready to feed products analysed in this study, were not considered to be of concern. These results suggest that commercial complementary infant foods on the UK market may not contain minimum levels of minerals required for labelling declaration of micronutrient content (Commission Directive 2006/125/EC). This provides opportunities and scope for product optimisation to improve their nutritive value.     

杂粮淀粉在仔猪体内的消化率研究

以60 日龄生长猪为动物模型,考察4 种不同杂粮原料中淀粉(总淀粉、直链和支链淀粉、抗性和非抗性淀粉)的含量及其在生长猪回肠末端和粪中的表观消化率。结果表明：以干物质为基础,各种杂粮淀粉的含量因杂粮种属不同而差异较大。芋头淀粉和木薯淀粉的回肠末端消化率均显著高于(P ＜ 0.05)土豆和山药淀粉;所有淀粉在粪便中的表观消化率均达99% 以上。芋头淀粉和木薯淀粉因回肠末端消化率高而具有较高的葡萄糖供给效率,土豆淀粉和山药淀粉因后肠微生物的发酵而利用率升高。