Volume 11, Issue 6 -

This work aims at simulating a retort sterilization process of flexible packaging, performed in autoclave . ANSYS CFD © software has been used in this study to simulate the heat transfer inside the retort chamber. Flexible packaging filled with a pumpkin soup has been modelled. Three-dimensional (3D) geometrical configuration of the equipment has been designed and then simulated to evaluate the sterilization level achieved by each packaging inside the retort chamber. In particular, the internal temperature of the product situated in the cold spot of the chamber has been monitored during 5 min of the process (after reaching 85°C inside the product) in order to monitor the time/temperature trend. Experimental tests have been finally performed to validate the simulation model of heat exchange. The sterilization process takes place in a retort chamber by means of “overheated water sprayed” at 403 K and a pressure of 5 atm. Results show a good agreement between the simulated results and the real retort process and confirm the potential value of the simulation model to evaluate the process performance.

This paper builds upon the study by Marchini et al. (2014, International Journal of Food Engineering, pp. 557–571) and represents the second part of a research project whose general aim was to analyse and optimize, through simulation, the water distribution system of a dairy company. In the first paper, the authors focused on finding opportunities for recycling water in the distribution system of the targeted company, i.e. a dairy company located near Parma (Italy) and manufacturing Parmigiano Reggiano cheese and butter. In this work, we go ahead by analysing the thermal properties (such as, primarily, the temperature) of the water used inside the distribution system and of that discharged. To this purpose, we add the relevant thermal equations to the MS Excel TM simulation model developed in the first study. The resulting model is able to derive the temperature trend of water inside all the tanks of the distribution system. Situations where the temperature of the water used for rinsing is higher than the maximum allowed value of approx. 25°C are also highlighted and suggestions for improvement are proposed.

The Inventory Routing Problem (IRP) is an integrated logistic problem arising in several industries (e.g. petrochemical, grocery, soft drink and automotive). A vendor decides the optimal delivery strategy for a set of customers, taking into account their inventory policies and avoiding product stock-out in a finite and discrete time horizon. Delivery strategy includes the time and size of deliveries in order to minimize the total delivery cost. Most commonly studied are IRP real cases where a single homogeneous product with deterministic but time-varying demand is delivered over a finite time horizon. This paper is focused on an efficient methodology for industrial problems where a vendor resupplies a set of customers of heterogeneous products (as in the supermarket distribution industry). In this context, the paper reports on an effort facing the inventory routing problem for multi-category products per customer in conjunction with different inventory policies per category. The paper is motivated by real applications arising in the food engineering field. For instance, industries dealing with food’s distribution to stores located in a given geographic area. The planning strategy is formulated as a linear model. The core of the decision problem consists in determining both the delivery route and the corresponding day of activation along the time horizon. A decomposition of the problem into two phases has been proposed. A suitable penalty cost modeled by simulating the possibility of having an early or delayed product delivery on the delivery day returned from the inventory model (e.g. Economic Order Quantity) is the key feature of the first phase. In the second phase, deliveries are scheduled on a daily basis by taking into account the time windows associated to each customer. This is accomplished by using a constructive heuristic algorithm for the vehicle routing problem with time windows. Computational results on some realistic instances are presented and discussed.

Despite its worldwide presence, the characteristics of dairy industry may vary largely from one country to another and also between the different regions of a country. Farmers can form co-operatives or operate individually, while processors may transform very different amounts of milk into a diversity of dairy products. Moreover, the variety of dairy products that can be found in the market, the short-term expiry date of some of them, as well as the strong competition for a saturated market, lead to a complex environment, where the design and operation of the dairy factories require decision support tools for helping the decision makers. In this paper, it is considered the development of a decision support system for improving the survival chances of dairy plants in a competitive worldwide market. This tool is based in the implementation of an optimization process, where the performance evaluation of the feasible decisions is performed by means of simulation. The objective of the decision making covers the complete life cycle of the dairy plant from its design to its operation.

Parboiling is a hydrothermal processing technique during rice has to pass through many stages which alter the physicochemical properties and nutritional profile of grain. Different parboiling techniques have been developed for preparation and industrialization of rice. During parboiling process, starch granules are gelatinized and retrograded as a result various changes occur in rice kernel, which affects its quality parameters. Parboiling has marked influence on organoleptic properties, improved the strength and nutritional profile of grain. Parboiling treatment principally brings the characteristic change in rice grain such as milling, cooking, storage and eating qualities. Milling is an important unit operation for removing the husk and bran from the rough rice. Milling significantly affects the cooking and nutritional properties of rice. The important parameters focussed during milling are the head rice yield and kernel hardness. Milling technology is therefore geared to obtain maximum outturn of milled rice and to reduce breakage.

Pumpkin is widely used as a valuable food source and is gaining the attention of healthcare consumers. Dried powdering pumpkin is an alternative way to increase the consumption. For these reasons, a sound knowledge of the processes for drying and powdering of pumpkin is needed. Therefore, the present review summarizes data from the literature and points out promising areas for further research. This review focused mainly on various processes of dried pumpkin powder, including pre-treatment techniques which can influence the quality of dried product. Impacts of drying and storage methods on quality changes were also revealed in dried pumpkin powder such as the loss of color, changes in texture or an off-flavor and decreases in carotenoids or other nutrients. Moreover, this review also collected the basic information about characterization of pumpkin fruit and also chemical characteristics and nutritional values of pumpkin. Finally, the review pointed out areas for future research to further elucidate the best methods of dried pumpkin powdering for the local companies.

The aim of this study was to develop qualitative models that enable prediction of quality of carrots. A full factorial experiment including preharvest biocatalyst application, dipping treatments and storage temperatures was employed. Eleven different biochemical and microbiological quality parameters of carrot ( Daucus carota L.) were investigated. The effects of treatments on the shelf-life were investigated using discriminant analysis (DA). The lower storage temperatures (1°C) maintained the superior quality. Kinetic functions were applied to each parameter using the Levenberg–Marquardt algorithm to characterize the rate of change of quality. DAs significantly ( P < 0.001) differentiated between the combined effects of the preharvest biocatalyst treatment and storage temperatures. Four discriminant functions factored the differentiation of the quality attributes based on storage time. The models fit well to the experimental data for storage at 1°C. The second-order reaction equations allowed for prediction of ascorbic acid, sucrose and sugar–hexose ratio. First-order reaction equations that allow estimation of fructose, sucrose equivalent, total coliform and total fungi and O 2 were developed. The empirical evidence suggests that freshness was maintained in the carrots until day 14 ( P < 0.001). Ascorbic acid, sucrose and sugar–hexose ratio were the most relevant parameters to rapidly detect the postharvest changes following the second-order decay rate.

In a flow tube instrument modeled after a structurally simple and easy-to-use bubble viscometer, bubble ascent and liquid flow were examined to evaluate the physically defined viscosity of non-Newtonian liquid foods. For Newtonian and non-Newtonian test liquids, a dimensionless expression between the friction coefficient and Reynolds number, which was derived through analysis as an annular flow of liquid around bubble, indicated that the flow in the instrument was laminar. Prediction organized based on the empirical relation was advanced for evaluation of the non-Newtonian viscosity. The flow tube instrument was expected to be applicable to the conditions in drinking and eating, from a viewpoint of the characteristic shear rate ranging from 10 to 100 s −1 .

The present study includes the compositional analysis and pyrolysis products obtained from Desmodesmus sp. cultivated in anaerobic digested effluents (DADE) from 300°C to 800°C. Compared to Desmodesmus sp. cultivated in BG11 (DBG11), both species exhibited a hydrogen content of ca. 6%, ca. 7% of nitrogen, and ca. 0.56% of sulfur except carbon content, of which was lower than DBG11. Pyrolysis products of DADE consisted of aliphatic hydrocarbons, aromatic hydrocarbons, acids, nitrogen compounds, phenols, polycyclic aromatic hydrocarbons (PAHs), alcohols, aldehydes, and furans. Pyrolysis of DADE at 800°C produced 62.52% (the maximum yield) of pyrolysis products compared to 41.89% at 600°C. Considering the reasonably high yield and minimum release of pollutants, lower temperature (600°C) was found to be optimum for producing biofuel from DADE. A process combing anaerobic digestion and algae cultivation can be proposed as a direct and effective way to produce biofuel so as to reduce contaminations to the environment.

In this research, a novel polysaccharide-based bionanocomposite film was prepared via dispersion casting method. Nano-silicon dioxide (SiO 2 -N) was incorporated into soluble soybean polysaccharide (SSPS) at different concentrations (i.e., 0%, 1%, 3%, and 5% w/w dried SSPS). Mechanical (tensile strength, elongation at break, and Young’s modulus), physical (moisture content, water solubility, and moisture uptake), and barrier properties of bionanocomposite films were evaluated. Incorporation of 5% SiO 2 -N to SSPS matrix decreased water vapor permeability (WVP) from 7.96×10 −11 to 4.75×10 −11 g m −1 s −1 Pa −1 and oxygen permeability from 215 to 96 cm 3 µm m −2 day −1 atm −1 . Heat seal strength and mechanical properties of SSPS films were improved. Moisture sorption isotherm of SSPS films supported by SiO2-N was shifted to lower moisture content, and monolayer moisture content of the films decreased significantly ( p <0.05). In summary, SiO 2 -N is a potential filler in SSPS-based films for packaging materials.

Adsorption of black peanut skin anthocyanins, a natural pigment, onto various macroporous resins was optimized to develop a potential approach for large-scale production of black peanut skin anthocyanins. Seven different macroporous resins (AB-8, SP-207, LS-305A, HP-20, LS-305, DM-21 and LS-610B) were evaluated for the adsorption properties of the anthocyanins extracted from the black peanut skins of Arachis hypogaea L. The adsorption experiment proved that compared to AB-8, SP-207 and LS-305A, four resins, i.e., LS-610B, DM-21, LS-305 and HP-20 have relatively higher capacity of adsorbing black peanut skin anthocyanins from the aqueous solution, which are verified by the related adsorption experiments. The adsorption isotherm data was successfully described by Langmuir isotherm model and the pseudo-second-order rate model simulates the kinetic process well. Column adsorption and desorption tests further proved DM-21 is a promising adsorbent for field applications to recover black peanut skin anthocyanins from aqueous solution. The overall yield of pigment product was 14% based on dried black peanut skin, and anthocyanins purity is at about 5.7% in the pigment product.

Convective air drying characteristics and qualities of non-fried instant noodles at five temperatures from 80 to 120°C and velocities of 1.0, 2.0 and 3.0 m/s were investigated. Different mathematical models were fitted to study the drying behaviors and the Logarithmic model was the most adequate in describing the drying tests. Results showed that the drying process occurred in a falling rate periods and the effective moisture diffusivity increased with temperature and velocity, ranging from 4.41×10 −8 to 1.75×10 −7 m 2 /s with an activation energy of 16.73 kJ/mol. The rehydration attributes changed with both velocity and temperature. Increasing temperature and velocity decreased hardness, increased cohesiveness and resilience generally while had no impact on springiness. Drying temperature greatly influenced the color of noodles, whereas velocity displayed no significant effect. Microstructural analysis indicated that noodle presented hollow and porous structure with numerous and small voids, which might partly explain their distinct behaviors.

Microwave-assisted extraction of Trigona propolis in closed vessel was applied to reduce the extraction duration and volume of solvent. The effects of operating parameters (temperature, duration, power applied and sample to solvent ratio) on the extract yield, total phenolic, total flavonoids and antioxidant activity measured by DPPH method were measured after extraction. Without temperature control, propolis extract showed improvement in yield and quality by extending the extraction duration at low microwave power. However, the yield dropped significantly and the ethanolic solvent was released when the vessel pressure increased dramatically at higher power applied. The effects of extraction duration, temperature and the sample to solvent ratio were further investigated using a constant power of 300 W with temperature control. As long as the temperature was precisely controlled below 125°C, propolis extraction can be accomplished in shorter time (15 min) and less solvent (sample to solvent ratio of 1:5 (w/v)) without degradation compared to maceration.