EFFECT OF SHAPE ON POTATO AND CAULIFLOWER SHRINKAGE DURING DRYING

2000

ABSTRACT Shrinkage of potato cubes, parallelepipeds and cylinders was addressed during drying. A basic methodology by using image analysis was set-up in order to measure and monitor geometrical changes along the drying process. Both measurements by image analysis and directly with a calliper were carried out. Results from both methods showed a good agreement with no bias. Particle shape was found to influence shrinkage in a different way according to the axis. In fact the larger dimension shrinks less than the shorter one. This could be linked to the influence of the core drying in shrinkage. Experiments were also carried out for cauliflower stems. The difference in shrinkage between direct…

Dried-Fruit Storage: An Analysis of Package Headspace Atmosphere Changes

2019

The quality of packaged dried foods depends on storage conditions and is determined largely by the initial gas composition inside and the transference through the container. The aim of this work was to analyze the O2 and CO2 concentrations within the internal atmosphere of the packaging. In this study, dried apricots and raisins were packaged in glass jars and polypropylene trays thermosealed with different polymers, and stored at 5, 15, 25, and 35 &deg

EMG assessment of chewing behaviour for food evaluation: Influence of personality characteristics

2007

Abstract The aim of the present study was to evaluate the chewing behaviour stability over time and the influence of personality characteristics on chewing behaviour in order to assess the use of EMG for food assessment. From a set of eighty three subjects, thirty-two subjects were classified as personality type A or B (Jenkins Activity Survey questionnaire) and then recruited for the experimentation. Two types of assays were performed: Assay I: chewing gum for 10 chews and Assay II: chewing gum for 50 s. Only in two cases (6.3%) did the subject change his/her chewing behaviour; in the other cases, subjects’ chewing behaviour was stable over time (two months test). In both assays significan…

Application of low intensity ultrasonics to cheese manufacturing processes.

2002

Ultrasound has been used to non-destructively assess the quality of many foods such as meat, fish, vegetables and dairy products. This paper addresses the applications of low intensity ultrasonics in the cheese manufacturing processes and highlights the areas where ultrasonics could be successfully implemented in the future. The decrease of ultrasonic attenuation during the renneting process can be used to determine the optimum cut time for cheese making. The ultrasonic velocity increases during maturation for those types of cheese that become harder during this manufacturing stage, thus being an indicator of the maturity degree. Moreover, ultrasonic measurements could be linked to sensory …

Effect of Temperature on Isobutyric Acid Loss during Roasting of Carob Kibble

1997

The high content of isobutyric acid in carob (Ceratonia siliqua L.) constitutes a handicap for some of its potential uses due to the undesirable smell produced by that compound. In this study the loss of isobutyric acid during roasting was approached by heating the carob kibble at temperatures from 120 to 180 °C in two local cultivars (Matalafera and Lisa). The initial content of isobutyric acid varied between 6.3 (Lisa) and 9.4 (Matalafera) g isobutyric acid/kg dry solid. Results showed that the process can be described by a diffusive model. The activation energy of the process is about 55 kJ/mol for both cultivars. Keywords: Carob pod; roasting; isobutyric acid; diffusion

Sulphur dioxide evolution during dried apricot storage

2009

Abstract Sulphur dioxide is used as a pre-treatment to facilitate drying, improve product quality and extend the shelf life of apricots. During storage, SO 2 losses are observed, thus reducing the effect of this agent. The aim of this paper is to analyze the evolution of SO 2 content in dried apricots packaged in different types of containers, namely glass and polypropylene trays thermosealed with different films (oriented polyamide OPA + polyethylene PE and polyamide PA + polypropylene PP). The packaging atmosphere was air in all cases. Storage was carried out at constant temperature: 5, 15, 25 and 35 °C. Stored samples were analysed periodically over 12 months. In order to model the SO 2 …

Modeling of the process of moisture loss during the storage of dried apricots

2011

[EN] Moisture content is a reference parameter for dried food because the growth of most microorganisms is inhibited below certain water activity levels. In addition, it has a determining influence on the evolution of important parameters, such as color and flavor, and on other properties and deterioration reactions, such as texture, oxidation processes and nutritional value. During the storage of some dried fruits, moisture is produced due to Maillard reactions and exchanged with the surrounding environment through the packaging. The evolution of dried foods during their shelf life depends on the storage conditions. The aim of this study is to analyze the evolution of the moisture content …

High Pressure Solubility Data of the System Limonene + Linalool + CO2

2001

The feasibility of deterpenating orange peel oil with supercritical CO2 depends on relevant vapor−liquid equilibrium data because the selectivity of this solvent for limonene and linalool (the two key components of the oil) is of crucial importance. In this work the solubility data for the CO2 + limonene + linalool ternary system were measured at (318.2 and 328.2) K. The range of pressures covered was from (70 to 110) bar. Two different mixtures of limonene + linalool were used:  a 40 mass % limonene + 60 mass % linalool mixture and a 60 mass % limonene + 40 mass % linalool mixture. To correlate the obtained results, two equations of state were successfully used (Peng−Robinson (PR) and Soav…

The Storage of Dried Apricots: The Effect of Packaging and Temperature on the Changes of Texture and Moisture

2012

During storage, the packaging material was crucial in the product's moisture variation. The aim of this work was to study the changes of both the moisture content and the texture of dried apricots packaged in two types of containers, namely glass and polypropylene trays, which were thermosealed with two different films and stored at a constant temperature (5, 15, 25 and 35C). The moisture content and texture of the product were analyzed periodically over a period of 12 months. In addition, a differential scanning calorimetry of the product was carried out for a better understanding of the relationship between these parameters. In samples packaged in films, the maximum force value increased …

A method for the calculation of the heat transfer coefficient in potato drying

1993

A method for the determination of the heat transfer coefficient was proposed for the first falling drying period of potato cubes. During this period, heat and mass transfer were considered as coupled phenomena. Temperature calculation inside the sample was performed using the macroscopic heat transfer balance. The heat transfer coefficient was computed by means of parametric identification, using the Gauss–Newton method. The figure obtained for the heat transfer coefficient shows good agreement with other sources.

Validation of a biophysical drug absorption model by the PATQSAR system

1999

Absorption rate constants (in situ rat gut technique) and in vitro antibacterial activities of twenty fluoroquinolones have been evaluated. A biophysical model that relates the absorption of the compounds with their lipophilicity was fitted. The model considers the absorption process from the intestinal lumen as the sum of two resistances in series: aqueous diffusional barrier and lipoidal membrane. Even if partitioning into the membrane and membrane diffusion are both enhanced for lipophilic compounds, the absorption rate constant is limited by the aqueous diffusion. To estimate the influence of structural modifications on each property and to establish the role of lipophilicity in control…

CHEESE HARDNESS ASSESSMENT BY EXPERTS AND UNTRAINED JUDGES

2001

Although expert assessment of food characteristics is recognized as a key step in product development, the use of consumer based measurements is sometimes recommended as an equivalent to the experts. From cognitive psychology, support of the role of perceptual learning is found in some instances, although this could not be relevant in others. To address this point performance analysis of experts and untrained panelists in cheese texture evaluation was carried out. Neither the untrained panelists nor the experts were familiar with either the scales or the kind of cheese. The same Cheddar cheese was given to 44 untrained subjects in three trials to assess hardness. The results showed that the…

Wine Aroma Concentration by Using a General Purpose simulator (ProSim)

1995

In this work is proposed the application of the ProSim process simulator for the analysis of wine aroma concentration by performing a two-level simulation: First, ProSim is used to attain a preliminary design of a distillation tower, and afterward the simulator is employed to analyze the behavior of the tower in a more precise way. The UNIFAC model was used for nonideal behavior description of the mixtures. In this application, the concentration of a 13-compound mixture was simulated. In fact, the numerical methods implemented in ProSim made it possible to attain the convergence quickly even with minor compounds. The results obtained showed that the use of ProSim results to be very advanta…

Exploring the use of low-intensity ultrasonics as a tool for assessing the salt content in pork meat products

2015

Meat industry demands non-destructive techniques for the control of the salting process to achieve a homogeneous final salt content in salted meat products. The feasibility of using low-intensity ultrasound for characterizing the salting process of pork meat products was evaluated. The ultrasonic velocity (V) and time of flight (TF) were measured by through-transmission and pulse-echo methods, respectively, in salted meat products. Salting involved an increase of the V in meat muscles and a decrease of the time of flight in whole hams. Measuring the V before and after salting, the salt content could be estimated. Moreover, online monitoring of the salting process by computing the TF could b…

Drying of shrinking cylinder-shaped bodies

1998

Abstract A mathematical model has been developed for the prediction of sample temperature, average moisture and moisture distribution in a cylinder-shaped solid during the drying process. The effect of shrinkage was taken into account. The macroscopic heat balance and the microscopic mass balance combined with Fick's law were simultaneously solved using the Runge-Kutta-Merson method and a numerical finite difference method. The effective diffusion coefficient was expressed as a function of sample temperature and local moisture content. Using an experimental drying curve determined at 90 °C, the diffusional equation was identified for broccoli stems, and was used to predict the average and l…

Alegación en hecho, y derecho por Juan Bautista Sessè ciudadano, y Doña Thomasa Manzanares y Assio, consortes, con el licenciado Antonio Mulet, y Fel…

A la part superior de la port.: "Jesus, Maria, Joseph" Signat al final: "D. Thomas Vicente Ballester de Moya" Port. orlada Gravs. xil. enmarcats a la port. de la Mare de Déu i de "S. Antonio de Padua" Caplletra ornada al començament del text Sign.: [A]2, B-I2, K1 El full pleg. és un arbre genealògic Reclams