Pasta Drying Process Research Articles

Pasta regrind: The effect of drying temperature on its functionality as a novel ingredient

Cutting and drying steps in pasta production result in by-products, named pasta regrind, which are used mainly as animal feed. Pasta regrind could be a valuable ingredient butits techno-functional properties need to be studied also in relation to the pasta drying process. Hence, the effect of three different drying temperatures, low (LT), high (HT) and extremely high (XHT) on the techno-functional properties of pasta regrind was investigated. Increasing drying temperature increased the water-retention capacity of pasta regrind. Semolina-based bread was selected as a model system to use pasta regrind as a functional ingredient. Bread was made with different percentages (w/w) of pasta regrind (10%, 25%, 50% 100% of HT, 25% of LT and 25% of XHT) mixed with semolina flour. The addition of HT regrind increased the hardness of the crumb whereas decreased bread volume. 25% LT regrinds had no effect on the bread crumb’s hardness and porosity compared to 100% semolina bread. Confocal laser scanning microscopy revealed a dense gluten network only in 25% LT bread. Therefore, HT and XHT regrinds are not suitable ingredients for leavened products while LT regrind can be efficiently used for bread production.

PRESSING AND DRYING PASTA

The article is devoted to the topic of pasta and such technological processes of their production as kneading pasta dough, pressing or forming pasta, drying finished products. The characteristic features and defining parameters for each of the processes are described. The main parameters that affect the quality of the finished product for the technological process of kneading the dough are humidity, temperature and the process of vacuuming the dough, for the process of forming pasta – pressing pressure and humidity of the dough, for the drying process-temperature, speed and humidity of the drying air. The character of the dough movement in the screw chamber and the pressing head during the molding of pasta is described, the drying process of pasta is considered, the drying curve of pasta is shown.

Drying kinetics of millet, poamce and wheat based pasta and its effect on microstructure, color, water absorption and pasting properties

The aim of this work was to study drying kinetics and to analyze effect of drying temperature on different quality attributes of functional pasta. Drying characteristics of developed millet based pasta were investigated at a temperature range of 50–80 °C in a convective tray drier at constant air velocity of 0.05 m s−1. Results indicated temperature significantly affected drying process of pasta. Drying of pasta samples took place during falling rate period. Different mathematical models were evaluated for goodness of fit by comparing coefficient of determination (R 2 ), chi square (χ 2) and root mean square error (RSME) parameters. Comparability of statistical parameters led to conclusion that logarithm model showed the best results for describing drying behavior of pasta. Effective moisture diffusivity (D eff ) of samples increased with increase in drying temperature and ranges from 2.01 to 2.86 × 10−9 m2 s−1. Activation energy (E a ) value evaluated was 15.23 kJ/mol. Quality parameters like water absorption and color of dried pasta are significantly (P < 0.05) affected with drying temperature. Scanning electron microscopic observations showed that pasta microstructure was affected by temperature as pasta dried at 80 °C seems to have denser and more continuous gluten network.

A rigorous analysis of simultaneous heat and mass transfer in the pasta drying process

This study presents a two dimensional analysis of coupled heat and mass transfer during the process of pasta drying. Velocity and temperature distributions of air flowing around the pasta are predicted in steady state condition. Using these profiles and the similarity between heat and mass boundary layers, local convective heat and mass transfer coefficients were determined on different points of pasta surface. By employing these values, the solution of coupled heat and mass transfer equations within the pasta object in unsteady state condition was obtained. Furthermore the effects of operating conditions such as velocity, temperature and relative humidity of air flow on drying rate of pasta were studied. Sensitivity analysis results show that the effects of air temperature and relative humidity on the rate of drying are more important than the effect of air velocity. Finally, the results obtained from this analysis were compared with the experimental data reported in the literatures and a good agreement was observed while, no adjustable parameter is used in the presented model.

Advanced design of the pasta drying process with simulation tools

This work aims at investigating the industrial drying process of pasta. The analysis carried out consists of two parts. First, a scientific method, called finite difference model (FDM), was applied to the drying process of pasta, with the purpose of developing a simulation model able to reproduce the process. The model was implemented under Microsoft ExcelTM, through an ad hoc spreadsheet that automatically calculates the trend of temperature and moisture as a function of time for a simple cylindrical product of infinite length (i.e., spaghetti). The results obtained from the Microsoft ExcelTM simulator were then validated by means of: 1) the comparison with a real industrial case; 2) the comparison with the results provided by computational fluid dynamics (CFD) software, called ‘TdynMultiphysics’ (for the thermal results). In the second part, we analysed the industrial equipment used for the drying process, i.e., the static dryer. A CFD model was developed with the commercial software Tdyn Multiphysics, with the purpose of assessing the performance of four different layouts of a static dryer for pasta. The ultimate aim is to investigate the performance of the drying process as a function of the dryer configuration in order to optimise it.

Evaluation of Pasta Thermal Treatment By Determination of Carbohydrates, Furosine, and Color Indices

The drying process of pasta plays a crucial role in assuring its final quality, since the operational conditions of this process may imply thermal and mechanical damage that also affect final product yield. In this work, independent analyses on furosine, carbohydrates, and color indices (red, yellow, and lightness) have been conducted on pasta samples produced by an Italian pasta factory in order to correlate the examined parameters with pasta drying process. The investigation has been focused on pasta samples having different shapes in order to evaluate how the considered parameters are affected by the specific thermal process scheduled for each pasta format. The same analyses were also performed on semolina used for each pasta sample production, with the aim of verifying whether furosine amount, color indices, and maltulose change in relationship with Maillard reaction (MR) occurring during the drying process. Maltulose presence has been evaluated in semolina for the first time. In addition, the study has been extended to commercial pasta samples of different qualities; a Principal Component Analysis (PCA) has also been conducted to combine together all observed data with the aim of proposing an overall quality index. Finally, a statistical model based on chemical and color parameters as independent variables was successfully developed (R2 = 0.990) by means of a multiple linear regression (MLR) analysis to predict commercial pasta cook values and drying cycles as consequences.

Prediction of pasta drying process based on a thermogravimetric analysis

The drying process of durum wheat semolina dough was measured by thermogravimetry in the temperature and relative humidity ranges of 30–90°C and 0–80%, respectively, in order to predict the drying process of pasta under any drying conditions. About 20% of the water was evaporated during the constant drying-rate period which has been ignored in previous studies. It is demonstrated that the constant drying-rate period should be taken into account in order to predict the drying curve with a high accuracy. The drying rate during the constant drying-rate period and the mass transfer coefficient estimated by the thermogravimetric analysis were expressed as functions of the temperature and relative humidity, and they were useful for predicting the drying processes of pasta under any drying conditions including the programmed ones.

Parametric study of the effect of reference state on energy and exergy efficiencies of a small industrial pasta drying process

The paper describes a performance evaluation of the industrial pasta process system in Gaziantep, based in Turkey, on energy and exergy analyses. The case study covers the actual system data taken from the system. General energy and exergy analysis of the system are introduced. This analysis, applied to the system using actual thermodynamic data for its performance evaluation in terms of energy and exergy efficiencies, is presented. In addition a parametric study of the effect of varying reference state properties on the energy and exergy efficiencies of the system has been conducted to find optimum performance and operating conditions, and is explained.

Exergy analysis of industrial pasta drying process

In this study we present an energy and exergy modelling of industrial final macaroni (pasta) drying process for its system analysis, performance evaluation and optimization. Using actual system data, a performance assessment of the industrial macaroni drying process through energy and exergy efficiencies and system exergy destructions is conducted. The heat losses to the surroundings and exergy destructions in the overall system are quantified and illustrated using energy and exergy flow diagrams. The total energy rate input to system is 316.25 kW. The evaporation rate is 72 kg h−1 (0.02 kg s−1) and energy consumption rate is found as 4.38 kW for 1 kg water evaporation from product. Humidity product rate is 792 kg h−1 (0.22 kg s−1) and energy consumption rate is found about 0.4 kW for 1 kg short cut pasta product. The energy efficiencies of the pasta drying process and the overall system are found to be as 7.55–77.09% and 68.63%. The exergy efficiency of pasta drying process is obtained to be as 72.98–82.15%. For the actual system that is presented the system exergy efficiency vary between 41.90 and 70.94%. Copyright © 2006 John Wiley & Sons, Ltd.

Modelling of high quality pasta drying: mathematical model and validation

The pasta drying process was studied using an engineering approach. The phenomena of mass and heat exchange between pasta samples and air was modelled according to the classic transport approach applied to a hollow cylindrical shape pasta. Data from the literature and from measurements were used to fix the material parameter values of both the air and dough phases. Theoretical correlations were used to obtain a good estimate of mass and heat exchange coefficients between dough samples and air. The proposed model was set by choosing the mass transfer coefficient as the unique optimisation parameter, determined by best fitting of the experimental water content data obtained under given conditions in a static dryer. The model was then validated at different temperature and air humidity drying profiles and a good agreement with the experimental results was found. Finally the model was applied to different process conditions and the drying time was calculated from the simulations.

Evaluation of short cut pasta air dehydration assisted by microwaves as compared to the conventional drying process

Drying is one of the most important unit operations of the industrial production of pasta, both from the viewpoint of the final product quality and from the economical aspects of its manufacture. This work was aimed at evaluating the efficiency of air drying the type Penne short cut pasta with the assistance of microwave energy, from 23% to 12% (w.b.) product moisture, by using at first an adapted domestic microwave oven and later transferring the bench scale experimental parameters to test a continuous pilot scale microwave assisted hot air rotary dryer. The observed average drying time was reduced by more than ten times when compared to the air conventional drying, without being harmful to the appearance of the final product. An estimate of the economy of using a continuous hot air rotary dryer assisted by microwaves in industrial scale showed that this new option could be potentially competitive with the traditional short cut pasta drying process.

Prediction of Microbial Death During Drying of a Macaroni Product

Death of Staphylococcus aureus 196E in a semolina-egg dough was studied during a variable temperature simulated drying test. Data for the death rate constant of the organism collected under steady state conditions of constant temperature and water activity were used to predict the amount of death occurring in the unsteady state test. Very good agreement was found. Utilizing the steady state information it was predicted that over 5-log cycles of kill would occur for S. aureus 196E and Salmonellae anatum NF3 during the pasta drying process. This indicates that kill caused by the process itself may not be enough if high levels of these pathogens occur initially in the dough.