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A 2-dimensional energy balance approach was used to model temperature distribution in conduction heated conically shaped bodies. A numerical solution by finite differences to the second order partial differential equation for heat conduction served as basis for the model. The cone was divided into small volume elements. The inner elements were concentric rings of rectangular cross section while those at the side surfaces had triangular cross-sections. Energy balance equations for the volume elements were solved explicitly. Acrylic of known thermal properties was used to fabricate cones in 3 different geometries and sizes, varying from a frustum to a point cone. Every cone had 3 or 4 thermocouples (36 gauge, T type) inserted at different locations. Heat penetration tests were carried out in a water bath with constant and variable water temperatures. Experimental temperatures at different locations within the cones agreed well with temperatures predicted by the model. Use of the model to predict the location of the slowest-heating point or "cold point under different processing conditions was also demonstrated.

Mango fruit (Mangifera indica L., cv Nam Doc Mai number 4) of three different sizes, were evaluated for their instrumental texture properties, in accordance with the exporter requirements at commercial harvesting time. The size classification of mangoes was determined by the mass of the fruit. The large size weighed more than 351 g, the medium size 330-350 g, and the small size 260-329 g. The results of deformation at a force of 20 N, energy of absorption from a compression test and the average hardness from puncture tests varied for the different sizes. The large size showed firmer and more elastic in relation to the compression force, as well as the hardest and most rigid in response to the puncture force. The peel and flesh strengths of large, medium, and small sizes at the commercial harvesting date did not differ with bio-yield force, which indicated that the strength of the flesh under the peel was very close to the rupture force, which indicated the strength of peel. Examples of the applications of these properties for postharvest handling are described.

A cone frustum is an alternative shape for packaging thermally processed foods that can be useful in modeling the increasing number of microwaveable, ready‐to‐eat conical‐shaped food containers seen on supermarket shelves. Thermal processing in a cone frustum can be optimized by using numerical models for heat transfer to predict temperature distribution profiles, together with thermal destruction kinetics of target organisms and nutrient/quality factors. Iso‐lethality curves, showing combinations of process time and retort temperature that deliver equal lethality, were developed for each of three different cone frustum geometries (different dimensional proportions of major and minor diameters and height). Total volume average quality retention was determined for equivalent process time‐temperature combinations for quality factors with assumed thermal degradation kinetic parameters (D and Z‐values). Response of quality retention to the equivalent process combinations (designated by their retort temperature) revealed optimum process conditions that delivered maximum quality retention. The effect of kinetic parameters, thermal properties, and surface heat transfer coefficient on quality retention response to equivalent process conditions was also studied and compared with findings reported in the literature for the case of more traditional finite cylinder shapes.

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Mango (Mangifera indica L.) ‘Nam Dok Mai Si Thong’ is an important cultivar for export from Thailand. Export mainly takes place via air transport, but for about 2 h at the loading area (tarmac), unit loading devices (ULDs) are exposed to ambient environmental conditions. In this research, the effects of different temperature conditions at the loading area (tarmac) and the distance of the production area from the tarmac on the quality of fresh mango fruits were studied. The treatments included three temperature conditions for 2 h (simulated handling in tarmac)—constant temperature (20 °C), non-insulated or insulated and exposed to sun—and two distances of the tarmac from the production area—short distance (i.e., transport occurring 53 h after harvest) and long distance (i.e., transport occurring 70 h after harvest). The temperature variation in the boxes exposed to the sun was greater in the non-insulated than in the insulated boxes, but this effect was more pronounced in fruit from the short-distance production area (28.1 °C insulated and 36.9 °C non-insulated) than in fruit from the long-distance production area (34.2 °C insulated and 38 °C non-insulated). Insulation and short distance increased the shelf life, decreased weight loss, delayed the decrease in average firmness and rupture force, etc. The insulation of mango fruit boxes mitigates the deleterious effect of exposure to 2 h of direct sun by reducing the increase in temperature, thus improving the shelf life and quality of mango fruit.

This research aimed to determine the salt content of canned sardines in tomato sauce using NIR spectroscopy compared with traditional methods employing an auto-titrator, which are more consuming in terms of time and chemicals used. Scanning of NIR radiation was performed using an FT-NIR spectrometer with a wavenumber range of 12,500-4000 cm -1 (800-2500 nm) with the diffuse reflection mode. Model development was achieved using partial least-squares regression from three groups of samples, which were the sample group that included salt-adjusted samples, the sample group that did not include salt-adjusted samples and the sample group that included only salt-adjusted samples plus five non-salt-adjusted samples. The model from the sample group that did not include salt-adjusted samples used the first derivative + straight-line subtraction spectra between 9403.8 cm -1 and 4242.9 cm -1 with nine partial least-squares factors providing the lowest root mean square error of prediction (RMSEP), with a coefficient of determination of calibration (R 2 ) of 0.90, root mean square error of estimation of 0.039%, coefficient of determination for prediction (r 2 ) of 0.85, RMSEP of 0.046%, average error of prediction (bias) of -0.002% and ratio of standard error of validation to the standard deviation of 2.58. The sample group that included salt-adjusted samples had a skewed distribution. The model returned an RMSEP of 0.109% on test samples, but the performance-to-interquartile range index indicated that this was a poor calibration. For the smaller salt-adjusted samples plus five non-salt-adjusted samples, cross-validation indicated the potential to evaluate salt in canned sardines (root mean square error of cross-validation = 0.158%). It was found that the vibration of water had an effect on the prediction accuracy as well as the vibration of starch and protein.In addition, the CONH 2 and CO 2 H groups, which are common amino acid functional groups, also showed an effect.These findings represent novel findings concerning the use of NIR spectroscopy to determine salt that has no signal of its own in the NIR region.

In the seafood industry, a large amount of salt is added to preserve seafood products. During processing, it is necessary to desalt the products for the sake of customers' health. Unlike a large-scale factory, many small enterprises lack tools and methods for desalting and measuring the efficiency of the desalting process. We have developed a rapid prototype salt-sensing system that can measure the desalting efficiency. Dried salted jellyfish are used as testing materials to evaluate the system. The rapid prototype comprises a microcontroller, a wire, and a liquid crystal display. Using a simple mapping between electrical conductivity and actual data obtained from the measurement of samples, the sensing system is successfully calibrated. A method of desalting the salted jellyfish material is also proposed. This desalting method and the newly developed simple sensing system for the desalting process are expected to make a significant contribution to the seafood processing industry.