高活性干酵母生产的干燥设备和工艺介绍

采用流化床快速干燥工艺进行高活性干酵母的生产,产品水分含量从67%干燥到5%,参数控制准确,活性保持良好。系统配套CIP和自动化控制,减少人工干预,保证工艺稳定。     

干污泥表面形貌及孔隙分布规律

污泥干燥焚烧以回收其热能的资源化利用正受到越来越多的关注。污泥干燥过程中,孔隙的大小及其分布直接影响污泥中液体及气体的传递过程．进而影响干燥速率。为研究干污泥表面形貌及孔隙分布规律,采用扫描电子显微镜观测了干污泥表面形貌。利用动态氮吸附法测量了干污泥的孔隙大小。利用数理统计方法研究了孔隙分布规律,研究结果表明干污泥的孔隙分布服从对数正态分布。建立了孔隙分布模型,求解了5种干污泥的孔隙分布特征参数,模型计算值与实际测量值吻合较好,均方根误差小于18．2％,所建立的干污泥孔隙分布模型具有一定的通用性及准确性。     

A research on sintering characteristics and mechanisms of dried sewage sludge

This study investigates the sintering behavior of dried sewage sludge and the related sintering mechanisms, considering sintering temperature and sintering time. Experimental results indicate that the characteristics are primarily influenced by sintering temperature. When the sintering temperature is increased from 1020 to 1050 °C, the specimens’ compressive strength and bulk density increase significantly, while water absorption decreases obviously, indicating an improvement of densification due to sintering. However, the compressive strength cannot meet the requirement for traditional ceramic products due to the release of organic matters and the formation of big pores in the products. Phosphorus in sewage sludge initially takes reactions with the formation of calcium magnesium phosphate and aluminum phosphate during sintering, which are helpful for enhancing the compressive strength. So, some materials with high contents of Al could be used to enhance the compressive strength of products. Heavy metals are fixed primarily inside the sintered specimens, with the As, Pb, Cd, Cr, Ni, Cu, Zn concentrations in the leachate found to be in the range of China regulatory requirements. These results reveal the feasibility of recycling dried sewage sludge by sintering as a construction material.     

用快干硅溶胶生产大型汽轮机导叶片的精铸工艺

介绍采用FOSECO公司生产的D COAT快干硅溶胶制壳工艺替代硅溶胶-硅酸乙酯复合制壳工艺，生产长为950mm、毛坯质量达42kg的汽轮机弯扭导叶片的制壳工艺，并对D COAT快干硅溶胶的快干机理和影响型壳性能的因素进行了探讨。D COAT快干硅溶胶采用水溶性高聚物增强，在湿度为30％～40％、风速为6～8m／s的干燥条件下，层间干燥时间仅为1～2h。D COAT快干硅溶胶型壳湿强度和高温强度高，残留强度低，透气性好，已成功应用于汽轮机大型叶片的批量生产。     

Survey of mycotoxins in dates and dried fruits from Tunisian and Spanish markets

In an effort to enforce the knowledge on mycotoxin occurrence and co-occurrence in dates and dried fruits, 228 samples purchased from Tunisian and Spanish markets were subjected to multi-mycotoxin liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis of 16 mycotoxins. At least one mycotoxin was detected in 160 samples (70%). The frequency of contaminated samples was 83%, 80%, 64%, 59% and 26% for dates, dried vine fruits, figs, apricots and plums, respectively but none of the analyzed samples contained detectable levels of fumonisins (FB₁, FB₂, FB₃) or T-2 toxin (T2).The incidence and levels of mycotoxins varied in samples. The most prevalent mycotoxin was enniatin B (EnnB) (54%), followed by enniatinA₁ (EnnA₁) (36%); aflatoxins (AFs) (23%) and ochratoxin A (OTA) (22%). Thirteen samples contained AFs in levels that exceed the maximum limits established in EU legislation. The simultaneous contamination with 2–6 mycotoxins was observed in 51% of the analyzed samples. Lastly, intakes of the detected mycotoxins were calculated for average adult consumers and compared with the tolerable daily intakes (TDI). Data obtained were used to estimate the potential exposure levels.     

Pasta with Unripe Banana Flour: Physical, Texture, and Preference Study

ABSTRACT:  Banana is a starchy food that contains a high proportion of undigestible compounds such as resistant starch and nonstarch polysaccharides. Products with low glycemic response such as pasta are considered favorable to health. The objective of this study was to use unripe banana flour to make spaghetti with low-carbohydrates digestibility and evaluate its physical and texture characteristics, as well as consumer preference. Formulations with 100% durum wheat semolina (control) and formulations with 3 semolina: banana flour ratios (85: 15, 70: 30, and 55: 45) were prepared for spaghetti processing. The use of banana flour decreased the lightness and diameter of cooked spaghetti, and increased the water absorption of the product. Hardness and elasticity of spaghetti were not affected by banana flour, but adhesiveness and chewiness increased as the banana flour level in the blend rose. Spaghettis prepared in the laboratory (control and those with banana flour) did not show differences in preference by consumers. In general, the preference of spaghettis with different banana flour level was similar. The addition of a source of undigestible carbohydrates (banana flour) to spaghetti is possible without affecting the consumer preference.     

Role of pasteurisation heat treatments on rheological and protein structural characteristics of fresh egg pasta

The influence of egg pasteurisation and of thermal treatment(s) of fresh egg pasta on the protein network in the pasta were studied. Protein structural parameters were correlated with the physico-chemical and rheological characteristics of pasta. Twelve samples of fresh egg pasta were laboratory-produced, using raw or pasteurised whole egg, and either left untreated or submitted to one or two pasteurisation processes. Industrial pasteurisation of the eggs did not affect the protein network of pasta or its rheological and functional characteristics. Double thermal pasteurisation of egg pasta deeply influenced its structural characteristics, due to the formation of a tight protein network stabilised by disulfide bonds, in which ovalbumin plays an essential role. This tight protein network affected the cooking behaviour and the rheological properties of fresh egg pasta, decreasing weight increase upon cooking and break strain, while increasing break load and Young modulus. The indexes derived from these studies were applied to the characterisation of 24 commercial samples of fresh egg pasta. By using the Young modulus before and after cooking (rheological parameters) and protein solubility in buffer-saline (structural parameter), it was possible to discriminate three groups of samples as a function of the severity of their thermal treatment.     

Technological,nutritional and sensory properties of pasta fortified with agro-industrial by-products: a review

Reducing food waste is a priority to move towards more sustainable food systems. Since agro-food by-products are often rich in healthy compounds, such as fibre, phytochemicals, protein, fatty acids, vitamins and minerals, the waste valorisation could move through their transformation into ingredients useful for the formulation of functional foods. Pasta is a staple food widely consumed all over the world representing an optimal carrier for nutrients delivery. The incorporation of ingredients of a high added value obtained by agro-industrial by-products in pasta can improve its nutritional value and provides several health benefits. At the same time, the inclusion of new ingredients could modify the physical, chemical and textural properties determining the change of the organoleptic characteristics of fortified pasta, affecting its acceptability. Thus, the preparation of new pasta formulations with high nutritional properties, good technological and sensory characteristics represents a challenge for the food industry.     

A novel approach to authenticity control of whole grain durum wheat (Triticum durum Desf.) flour and pasta,based on analysis of alkylresorcinol composition

Since durum wheat is ∼20% more expensive than common wheat and considered of superior quality for the manufacture of pasta products, efficient methods for the detection of accidental or intentional admixtures of common wheat to durum wheat products are required. This paper describes a novel approach for the detection and quantification of whole grain common wheat adulteration in whole grain durum flour and dried pasta. We found that differences in the C17:0 to C21:0 alkylresorcinol homologue ratios between the two cereal species may serve as a suitable tool for whole grain durum product authentification. To detect and estimate adulteration, the C17:0/C21:0 ratios of flour and pasta admixtures with added whole grain flour of common wheat were analysed. A linear relationship between C17:0/C21:0 ratios and level of admixture in pasta samples showed that adulteration can be estimated within the range of 5–100% of admixture. Furthermore, di- and triunsaturated as well as oxygenated alk(en)ylresorcinols are reported to occur in Triticum durum Desf. for the first time.