Mathematical Modeling of the Coupled Transport Phenomena and Color Development: Finish Drying of Trellis-Dried Sultanas

A mathematical model for simulation of simultaneous heat and mass transport was developed to describe the drying kinetics during finish drying of trellis-dried sultanas. In this model, the governing partial differential equations for heat and mass transfer for a solid spherical body were numerically solved using a finite difference technique. In addition, a kinetic model was coupled to the heat and mass transfer calculations to simultaneously predict the evolution of product color during the drying process. This allows predictions of moisture content, temperature, and color profiles of the product in a space–time domain during the drying process as a function of various operating conditions.

Predictions compared well with the experimental values, implying that the proposed numerical model can be used with confidence for the simulation of the important transport phenomena in optimizing the design and operation of a drying system for sultanas that maximizes the retention of the desired product color. The work has demonstrated the importance of establishing optimal and closely controlled drying conditions because significant effects of the key operational parameters on drying kinetics and the associated changes of product color were found. The modeling approach proposed here can be extended to other products and for incorporation of other product quality indices.     

The microbiological safety of ready-to-eat specialty meats from markets and specialty food shops: A UK wide study with a focus on Salmonella and Listeria monocytogenes

From 2359 specialty meats (continental sausages, cured/fermented, dried meats) sampled from markets and specialty food shops, 98.9% of samples were of satisfactory or acceptable microbiological quality. However, 16 (0.7%) were unsatisfactory as a result of Escherichia coli, Staphylococcus aureus or Listeria spp. contamination (≥10² CFU/g), and nine (0.4%) were unacceptable due to presence of Salmonella spp. or Listeria monocytogenes (>10² CFU/g). Meats with unacceptable levels of L. monocytogenes were within shelf life (range: 8–143 days remaining). Nine different subtypes of L. monocytogenes were detected with sero/AFLP type 1/2c VII predominating (37%), although this subtype was not overrepresented in any particular meat type (P > 0.05). Ninety-six percent of continental sausages and cured/fermented products were stored at <8 °C at premises, including seven of the nine unacceptable samples. These nine meats were all pre-packed prior to supply to retail premises (OR = 0.1 P = 0.003) indicating that contamination with bacterial pathogens occurred earlier in the production chain. Most samples (72.7%, 8/11) with unsatisfactory levels of E. coli were sliced on request, suggesting cross-contamination at point of sale. This study highlights the importance of ensuring that products do not become contaminated before final packaging, that storage conditions are controlled, and that durability dates are an accurate indication of the shelf life of the product so as to minimise the potential for L. monocytogenes to be present at levels hazardous to health at the point of sale.     

Amaranth flour,cassava starch and cassava bagasse in the production of gluten‐free pasta: technological and sensory aspects

The objective of the present research was to analyse the combined effect of pregelatinised cassava starch and bagasse (70:30) flour, cassava starch and amaranth flour on the cooking properties of pasta, verify the acceptance and buying intention of the product with the best technological characteristics, and finally compare them with commercial products made with regular and whole wheat flour. The vermicelli‐type pasta obtained in this study in the proportion of 10:60:30 (pre‐gelatinised flour:cassava starch:amaranth flour) showed the best results in the quality tests, with a cooking time of 3 min, mass increase of 101.5% and 0.6% solids loss to the cooking water, superior to the commercial pasta. Acceptance testing showed that this was a very good pasta (score of 7.2 on a 9‐point scale) and obtained 42% buying intention amongst the consumers. The elaboration of pasta containing pregelatinised cassava starch and bagasse (70:30) flour, cassava starch and amaranth flour was shown to be a feasible alternative with respect to the technological and sensory aspects, and could be consumed by those suffering from gluten intolerance.     

巧用面条机改进实验室制胶工艺

实验室采用面条机取代传统的剪刀制备生胶,工艺改进后的实验操作简便快捷,节省能源和资源,提高生产效率,还可提高生胶产品的质量。     

基于数字信号处理的发面机自动发酵系统控制优化

提出了一种基于数字信号处理(Digital Signal Processing,DSP)的发面机自动发酵系统控制的优化方法。对自动发酵系统中的自动入料系统进行优化,采用误差反馈控制算法进行面食发酵机械自动入料控制设计,在算法设计的基础上进行面食发酵机械自动入料系统的硬件设计。结果表明:设计的面食发酵机械自动入料系统人机交互性较好,系统稳定性较强,控制误差在迭代500次时仅为0.1%,实现精度控制。     

Aflatoxins levels in dried fruits and nuts from Rabat-Salé area, Morocco

The occurrence of aflatoxins (AFs) in dried fruits and nuts available in Rabat-Salé area (Morocco) was surveyed in this study. One hundred samples of dried fruits and nuts, purchased from retail shops and local markets from January to October 2006, were analyzed for AFs content by immunoaffinity (IAC) clean-up with liquid chromatography and fluorescence detection. Results showed that the incidences of total aflatoxins (AFT) and aflatoxin B1 (AFB1) in peanut, dried raisins, dried figs, walnut, and pistachio were 5%, 20%, 30%, 30% and 45% and 5%, 20%, 5%, 30% and 45%, respectively. The highest contamination levels of AFB1 were found in one walnut sample (2500 μg/kg) and one pistachio sample (1430 μg/kg). 5%, 20% and 20% of samples of pistachio, walnut and dried raisins exceeded the maximum tolerable limit (2 μg/kg) set for AFB1 by EU regulations. While 15% of dried figs samples were above the maximum limit (4 μg/kg) set by EU regulations for AFT. The present paper is the first report on the natural occurrence of AFs in dried fruits and nuts available in Rabat-Salé area in Morocco.     

强力牛肉干的研究

本文对强力牛肉干的主要营养成份进行了较全面的分析。通过人体实验结果表明强力牛肉干能改善人体维生素B_1、B_2,矿物质Ca、Zn,Fe的营养状况,是一种较好的运动员食品。     

Playing into the wild: A gesture-based interface for gaming in public spaces

Gestural-based interfaces have become one of the fundamental technologies that can determine the success of new computer games. In fact, computer games today offer interaction paradigms that go well beyond the use of remote controls, letting players directly perform exchanges with the objects and characters that compose the virtual worlds that are displayed in front of them. To perform such exchanges, new algorithms and technologies have been devised which include advanced visual recognition schemes, new video cameras and accelerometer sensors. At the same time, other important trends are also quietly emerging in the same domain: game designers, in fact, are slowly shifting their attention out of the walls of gaming fanatics homes, broadening their interests to computer games that can be played in public spaces, as exhibitions and museums. However, to the best of our knowledge, only a very limited amount of research experiences have taken into account the problem of producing computer games, based on gesture-based interfaces that well suit such settings. Hence, in this paper we address the problem of differentiating the design of a gesture-based interface for a console from the problem of designing it for a public space setting. Moreover, we will show that within a public space, it is possible to narrow down the vision algorithms that can well support the recognition of complex actions, whereas solely relying on a simple webcam. In particular, we will describe the design and implementation of an interface that well suits public immersive scenarios, since it is based on a simple and efficient set of algorithms which, combined with the intelligence given by the knowledge of the context of where a game is played, leads to a fast and robust interpretation of hand gestures. To witness this last aspect, we will report on the results obtained from the deployment of a computer game we specifically developed for public spaces, termed Tortellino X-Perience, which has been enjoyed by hundreds of visitors at the 2010 Shanghai World Expo.     

How the inclusion of mushroom powder can affect the physicochemical characteristics of pasta

In this study, a partial substitution of durum wheat semolina with three different species of mushrooms (white button, shitake and porcini) was undertaken to increase the nutritional value of the pasta. The cooking properties and textural characteristics of the pasta produced were also determined. The results showed that the addition of mushroom powder increased the cooking loss, as well as firmness and resistance of the uniaxial tension of the pasta. Porcini mushroom incorporation significantly decreased the swelling index, water absorption index and moisture content values of the cooked pasta, while, for the white button and shiitake mushrooms, there was no noticeable effect on either index compared with the control sample (containing exclusively durum wheat semolina). The addition of shiitake mushroom powder resulted in pasta with the highest firmness and tensile strength.