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Metal cans, while boasting excellent barrier properties, raise concerns about leaching and environmental impacts. This study explored plastic trays, a potential alternative for canned food packaging. First we delved into the plastic tray's characteristics, including its composition and permeability to oxygen and water vapor. Secondly, we conducted a comparison between the newly introduced plastic packaging and traditional metal cans, focusing on their interactions with food during the sterilization process and their effects on the quality of Tunisian pea sauce. The composition analysis revealed that the plastic tray was composed of polypropylene (PP) (with a single endothermic peak at 168 °C), while the film was found to have a mixture of PP internally and polyethylene terephthalate (PET) externally (with two endothermic peaks at 161.96 °C and 243.81 °C). Plastic trays showed good results in water vapor permeability (0.832 g/m2.d) but exhibited higher oxygen permeability (190 g/m2.d), raising oxidation concerns. Migration testing confirmed plastic packaging safety (<10 mg/dm2), while some simulants exceeded limits in metal cans. pH levels remained consistent between both packaging types, but varied significantly over a 28-day storage. Total Volatile Basic Nitrogen (TVBN) levels differed significantly between plastic and metal packaging, with notable variations observed over time with maximums of 0.3 mg/100 g for plastic trays and 0.17 mg/100 g for metal cans. Sensory evaluation revealed that tasters were adept at differentiating between canned pea sauce in plastic trays and metal cans (83%, 10/12), with taste and color exhibiting significant differences (p < 0.05). This underlines the impact of packaging material on canned food quality and consumer preference, with minimal influence on other sensory aspects. This data empowers manufacturers to make informed packaging decisions for a diverse range of canned foods. [ABSTRACT FROM AUTHOR]

Drying process was used in this study as a preserving method of octopus quality during storage. Octopus vulgaris quality attributes in terms of pH, water activity, color properties, total volatile basic nitrogen (TVB-N), trimethylamine (TMA), total viable count, and yeast and molds (YM) were evaluated. Samples were dried under sun drying and convective air drying and stored at ambient temperature. During storage, TVBN and TMA obtained were within the recommended level for good quality of dried samples. Accelerating shelf-life test was evaluated based on TVB-N, TMA, and YM, with shelf lives of 388 and 603 days for convective air drying and sun drying, respectively. [ABSTRACT FROM AUTHOR]

To respond to the various issues of conventional drying (textural defects of collapse-shrinkage and case hardening, microbiological contamination, poor rehydrability, degradation of active molecules caused by high wet-bulb temperature, weak drying kinetics, and marketing difficulty), swell-drying has proven high relevance in combining conventional drying processes with the Instant Controlled Pressure Drop (D.I.C.). The international team of "Research & Engineering Platform for intensifying Drying Processes (REPID)" has studied phenomenological models and experimental trials combining D.I.C. with new Interval Hyper-Active Drying (IHAD) processes. Currently, IHAD includes interval starting accessibility drying (ISAD), interval infrared airflow drying (IIRAD), and interval microwave airflow drying (IMAD). All these "interval operations" are sandwiched into cycles, each comprising double separate independent mechanisms; a short, hyper-focused active period (that generates and sweeps out vapor to the surrounding environment) alternated by a passive period of internal water diffusion/moisture homogenization. Since surface evaporation is highly intensive, the wet-bulb temperature stays low, although highly effective drying kinetics. Thus, the operation results in avoiding biochemical damage risks. Coupled with the D.I.C. texturing-decontamination, these drying operations are very effective in terms of drying kinetics, energy consumption, and product quality of heat-sensitive solids. It has led to the manufacturing of effective drying equipment. [ABSTRACT FROM AUTHOR]

The aim of this study is to develop a new emerging technique to solve the main problem of conventional drying which is energy consumption. Interval Starting Accessibility Drying (ISAD) is based on subjecting food samples to an instantaneous action of hot air close to the starting accessibility time, during very short time followed by tempering periods (< 5 min). Quince samples have been submitted to ISAD with a temperature of 40 °C and different air flow velocities (2; 3.5; and 5 m/s), with 15 s of active time and tempering periods between 1 and 5 min. The impact of ISAD compared to conventional drying has been significant in terms of effective drying time and energy consumption. Hence, ISAD treatment significantly reduces the effective drying time by about 89% to reach the same final water content for conventionally dried quince samples. These results have promoting technological impact: a significant gain of energy is gotten by inserting short tempering periods. Consequently, ISAD can be considered as a relevant way for intensifying the internal resistance to water transfer during pre-drying process of fruits. [ABSTRACT FROM AUTHOR]

Dehydrofreezing process involves water partial removal before freezing. This treatment has been proposed in order to reduce the negative impacts of conventional or even accelerated freezing, especially on the textural quality of high water content fruits and vegetables. Indeed, in such cases, freezing and thawing processes result in severe damage of the integrity of product's cell structure due to the formation of ice crystals. For this purpose, quince fruits (7 g H2O/g db) were subjected to convective air drying of 40 °C and 3m/s to reach different water content levels of 2, 1, and 0.3 g H2O/g db. Freezing profiles obtained at various freezing rates (V1, V2, and V3) for different water contents allowed the main freezing characteristics such as the Initial Freezing Temperature (IFT), the Practical Freezing time (PFt), and the Specific Freezing time (SFt) to be assessed. The impact of freezing rate was important on PFt and SFt, and more pronounced for high water contents (W between 7 and 2 g H2O/g db (dry basis)). Furthermore, IFT decreased sharply when initial sample water content decreased. Indeed, it started at −0.8 °C for W = 7g H2O/g db, while it reached a value of −8.2 °C for samples of W = 1g H2O/g db. Since convective air drying normally triggers shrinkage which causes a detrimental deformation of fruit structures, instant controlled pressure drop (DIC) treatment was used to improve the texture and enhance the whole dehydrofreezing performance and the final frozen-thawed product quality. Moreover, DIC implied a slight increase of PFt compared to untreated ones. On the other hand, quality attributes were estimated through the assessment of thawed water exudate (TWE g H2O/100 g db), color and texture (maximum puncture force as index of firmness): freezing rate and water content had great impacts on TWE. Hence, the lower the water content, the weaker the TWE. Furthermore, the TWE of the pre-dried quince (0.3 g H2O/g db) had higher value for DIC-textured samples than for the un-treated ones. Indeed, DIC-texturing leads to a well-controlled structure expansion of the cell wall. These textural changes resulted in more lixiviation of residual water. Consequently, water becomes more available, hence more releasable after thawing. Finally, the partial removal of water by air drying before freezing remarkably reduced the negative impact of freezing/thawing processes on final quince color. Decisively, the firmness of quince fruit increased with the decrease of water content level. Abbreviations: DMC: Dry Matter Concentration (%); DIC: Instant controlled pressure drop; W: Water content dry basis (g H2O/g db); IFT: Initial Freezing Temperature (°C); PFt: Practical Freezing time (min); SFt: Specific Freezing time (min); TWE: Thawed Water Exudate (g H2O/100 g db); L, a, and b: Color coordinates; (L): The degrees of lightness; (a) and (–a): The redness (a) or greenness (−a), respectively; (b) and (−b): The yellowness (b) or blueness (−b), respectively; ΔE*ab: Total color difference; L0, a0, and b0: Color coordinates of fresh or dried quince samples; SD: Standard Deviation; ANOVA: Analysis of variances; LSD: Least Significant Differences; cp: Specific Heat of the product depending on composition (dry material and water content)(KJ/kg K); cpd: Specific Heat of the dry material (KJ/kg K); cpW: Specific Heat of water (KJ/kg K); V1: Freezing rate without insulation; V2: Freezing rate with a food stretch film insulation with thickness e2 = 3 mm and thermal conductivity λ2 = 0.17 W/m K; V3: Freezing rate with a versatile flexible insulation (Armacell) with thickness e3 = 13mm and weak thermal conductivity λ3 = 0.036 W/m K; vd: Volume of dry material of quince sample (mm3); vH2O: Volume of quince sample water (mm3); vt: Total volume of quince sample (mm3); e0: Quince sample thickness (mm); e2: Insulation thickness in the case V2; = 3 mm; ; e3: Insulation thickness in the case V3; = 13 mm; ; λ0: Quince sample conductivity (W/m K); λ2: Insulation conductivity in the case V2; = 0.17 W/m K; ; λ3: Insulation conductivity in the case V3; = 0.036 W/m K; λd: Conductivity of quince sample dry material (W/m K); λH2O: Conductivity of water (W/m K); λequiv: Equivalent conductivity of quince sample versus water content (W/m K); mi and mf: Weights of the frozen and thawed samples, respectively [ABSTRACT FROM AUTHOR]

Ethyl formate (EF) was studied as a fumigant agent with the objective to replace methyl bromide (MB) for date fruit disinfestations. Date fruits Phoenix dactylifera 'Deglet Nour' with different initial moisture content (16% for dry dates, 20% for semidry dates, and a mixture of the two types) were separately fumigated with EF at different concentrations: 28.6,57.3, 85.9, and 114.6 g/m³ for 2 h. Experimental data of EF sorption during fumigation was successfully fitted to Peleg's model. This model allows the prediction of the effects of date moisture content and EF concentration on sorption behavior. Samples with different moisture content showed similar EF sorption behavior. Dates were artificially infested with carob moth (Ectomyelois ceratoniae (Zeller)) at different life stages. Eggs, third- and fifth-instars, and pupae were exposed to 28.6, 57.3, 85.9, and 114.6 g/m³ EF for 2 h. Among these life stages, fifth-in-stars were the most resistant to EF fumigation. A 2-h fumigation with 114.6 g/m³ EF provided complete control of eggs, third-instars, and pupae of carob moth, and generated 91.6% mortality of fifth-instars. A longer fumigation time or higher EF concentration may provide complete control of all life stages of carob moth. [ABSTRACT FROM AUTHOR]