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The application of chitosan and alginate coatings for a ready-to-eat (RTE) baked fish product was studied. An experimental design was used to investigate the effect of coating a polysaccharide concentration and glycerol addition on the safety (microbial growth) and quality (water loss and lipid oxidation) of an RTE fish product under optimal and abused storage conditions. The results showed that a chitosan coating with 1% (w/v) chitosan in 1% (v/v) acetic acid and 15% (w/w chitosan) glycerol, or a 1% (w/v) alginate coating with no glycerol and no crosslinking, showed the best performance in controlling the tested safety and quality parameters. The desirability method was used to identify the shelf lives of chitosan, alginate, and double-coated RTE products. The chitosan-coated samples showed the best performance with a three-fold shelf-life extension compared to the uncoated products stored at 4 °C. Moreover, the tested coatings demonstrated their ability to provide protective functions under abused storage conditions. These results strongly suggest that edible coatings have significant potential in enhancing the shelf life and safety of ready-to-eat (RTE) fish products. [ABSTRACT FROM AUTHOR]

Modified atmosphere packaging (MAP) is applied to extend the shelf life of fresh and minimally processed produce. Commonly used films, such as oriented polypropylene (OPP), are too impermeable to gases for successful MAP for products with moderate to high respiration rates, which has led to perforated systems. In order to design the perforation profile to ensure MAP targets for extended shelf life, it is necessary to evaluate which parameters affect the mass transfer through the perforations significantly. Perforations (270 μm, 450 μm and 750 μm diameter) were made in an OPP film under different temperatures and circulating air velocities, considering also different locations for the perforations. The results obtained showed that the perforation diameter is the most important parameter and can even be more significant than the total area of perforation (and therefore the number of perforations). Air velocity around the package and storage temperature were also relevant. Stacking during storage risks blocking perforations and therefore it is recommended to pierce trays on the sides in order to ensure better robustness. The package gas composition itself also affected mass transfer due to the interplay of oxygen flux with other gas fluxes, with particular relevance to the case of water vapour. [ABSTRACT FROM AUTHOR]

Several methods have been applied to estimate the permeance provided by perforations for perforated-mediated modified atmosphere package design. However, no dimensionless correlations have been proposed that comply with the principles of dynamic similarity and could therefore be applied with confidence to different packaging systems. The purpose of this work was to apply the Buckingham π theorem and obtain a generic correlation that obeys the principles of dynamic similarity. A correlation between the Stanton number (St) and the Schmidt (Sc) and Peclet (Pe) numbers was proposed and fitted to a set of 46 datapoints. The results showed that the correlation could be simplified to a proportionality between St and the reciprocal of Pe with a proportionality constant of 0.863. That implied that the influence of the perforation diameter was so dominant that the mass transfer coefficient (which is the same as the permeance given by the perforations) was simply proportional to the reciprocal of the perforation diameter, within the experimental variability. This result was validated with an additional set of 10 experiments. Mass transfer coefficients varied between 1 and 6 cm/s. • A dimensionless correlation obeying the principles of dynamic similarity correlated well the permeance to oxygen • Most other models that did not respect the principles of dynamic similarity performed poorly • The Stanton number was proportional to the Peclet and Schmidt numbers • The correlation can be simplified in many cases to permeance being inversely proportional to perforation diameter [ABSTRACT FROM AUTHOR]

Abstract: Modified Atmosphere Packaging (MAP) of fresh produce is a dynamic system and relies on the modification of the atmosphere inside the package, achieved by the natural interplay between two processes, the respiration of the product and the transfer of gases through the packaging film, which leads to an atmosphere richer in CO2 and poorer in O2. The challenge is how to integrate the mathematical modelling depicting product respiration rate and package permeability to simplify the packaging design process. The aim of this paper is to show the application of integrative mathematical modelling for MAP design of fresh produce. Mathematical models on product respiration rate and package permeability have been compiled into a comprehensive database and by using engineering principles were integrated on a web-based software platform (Pack-in-MAP®) which can be used to design and simulate the packaging needs for fresh produce. The aim of this paper was to illustrate the use of Pack-in-MAP® software and additionally simulate and validate the MAP design for fresh whole strawberry. The experimental and predicted gas compositions during storage were closely matching thereby showing the ability of Pack-in-MAP® software to determine the ideal packaging solution and predict the gas composition inside the package during storage period. Further, it can also evaluate the impact of temperature variation, and variability of product/package on gas composition providing a system which allows selection of suitable packaging materials for fresh produce. The Pack-in-MAP® software can be used to test several solutions on a value-for-money basis in order to achieve results while minimising costs and avoiding costly trial-and-error approaches. [Copyright &y& Elsevier]

Abstract: The objectives of this work were to determine the influence of the application of two different coatings (galactomannan and chitosan) and of storage temperature on the gas exchange rate of “Regional” cheese; subsequently, the coating that showed the greatest influence on the cheese gas exchange and simultaneously decreased the O2 consumption and the CO2 production rates was applied on cheese, being the shelf-life parameters monitorized through the performance of chemical and microbiological analyses. Both coatings caused a reduction of and of the cheese (between 0.19- and 1.30-fold for and between 0.19- and 1.50-fold for , depending on the temperatures). The cheese coated with the galactomannan coating was the one with the lower values of (between 0.195 and 0.635mL kg−1 h−1) and (between 0.125 and 0.900mL kg−1 h−1). Temperature was also found to have an important effect on and , its influence being well described by an Arrhenius equation with coefficients of determination, R 2, of 0.85 and above. The chemical and microbiological analyses showed that the application of the coating in cheese samples can be used to decrease the water loss and the colour changes during the storage time. The presence of the coating decreased the moisture loss of the cheese in 2.5% and 1.9%, and the weight loss in 3.8% and 3.1% at 4°C and 20°C, respectively. Also, the hardness of the cheese can be decreased as a result of the interaction of the presence of the coating with changes in the storing temperature. In the studied range (4–20°C) temperature has a statistically significant effect in moisture loss, colour change, hardness and total mesophilic bacterial growth. Overall, galactomannan coating can be used to improve “Regional” cheese shelf-life as it decreases and , improves its weight and appearance and can be used to incorporate natural preservatives to reduce post contamination. [Copyright &y& Elsevier]

Sorption isotherms of intermediate moisture content (IMC) products are essential to predict shelf-life of packaged moisture-sensitive product by modelling moisture uptake during storage and distribution. The effect of temperature and initial moisture content (MC) of IMC banana on the relationship between MC and water activity were investigated. Raw bananas were dried in a tunnel dryer at 2% relative humidity (RH), 70 °C, and a 3.2 ± 0.2 m s–1 air velocity. Drying procedure was carried out a number of times until various IMC levels were obtained (5%, 14%, 22% and 33% db for banana). Sorption isotherms of bananas were determined at 10, 20, 30 and 40 °C. The initial MC of IMC banana had no significant effect on the relationship between MC and water activity according to statistical analysis. All the sorption curves were found to be Type II. BET, GAB, modified GAB, Oswin, Halsey and modified Freundlich models were fitted to the data and it was found that the best results were obtained with a modified Freundlich equation. A secondary modified Freundlich model was built accounting for the effect of aw and temperature on the sample MC. [ABSTRACT FROM AUTHOR]

Abstract: Sorption isotherms of dried or intermediate moisture content (IMC) products are most important to model moisture uptake during storage and distribution. Working isotherms of IMC bananas were determined at five different temperatures (10, 15, 20, 30 and 40°C). Desorption and adsorption isotherms were determined at 10 and 40°C. All the sorption curves were found to be Type II, with non-zero moisture content (approximately 3–9% db for different temperatures) when the water activity was zero. Different models were fitted to the data and it was found that the best results were obtained with a modified Freundlich equation (valid from 0.06 to 0.76 water activity). The dependence of the models constants on temperature was investigated and the secondary models were built accounting for the effect of a w and temperature on the samples moisture content (R 2 =99%). Hysteresis was observed at 10°C and 40°C, but the effect was greater at 10°C. The net isosteric heat of sorption (working isotherms) varied from 0.85kJg−1 mol−1 to 7.67kJg−1 mol−1, decreasing with increasing moisture content. This effect was well described by an exponential function (R 2 >99%). These results provide reliable experimental data on sorption isotherms which is important for designing an optimized packaging system. [Copyright &y& Elsevier]

Abstract: Optimal environmental conditions and adequate packaging materials can be used to guarantee high quality product through shelf life. The aim of this study was to determine the influence of environmental conditions on quality parameters of intermediate moisture content (IMC) banana and identify the critical quality parameters of IMC banana during storage. IMC banana samples were placed in air-tight containers and stored according to a two level full factorial design with four factors (the storage temperatures, relative humidity, light level condition and air composition in the container). The quality indicators (moisture content, colour, rehydration capacity, penetration force and specific volume) were measured and sensory characteristics (overall opinion/acceptance, appearance/colour and firmness/texture) were also evaluated by a consumer group. It was found that temperature and relative humidity were the most influential environment factors for colour Hunter L, brownness index (BI) and rehydration capacity, acceptance and colour for IMC banana. L o (outer), moisture content and water activity were the critical instrumental quality parameters of IMC banana during storage. The 54% variation of overall sample quality throughout time was explained by all the quality parameters except specific volume. Shelf-life thresholds were defined from the good correlation between quality characteristics and the sensory acceptance, and for a sensory acceptance threshold of 5 (neither like nor dislike), the thresholds of L o, a w, moisture content and rehydration capacity were 49.4, 0.59, 13.5% wb and 12.2, respectively. [Copyright &y& Elsevier]

Abstract: It is very important to monitor characteristics of fruits (e.g. volume, shrinkage and porosity) during drying. There is lack of study in comparing different methods to measure dried product’s apparent volume. Specific volume, shrinkage and porosity of banana, pineapple and mango during air-drying were investigated. Banana, pineapple and mango slices were dried to different moisture contents down to approximately 5% wb in an oven dryer at 70°C. The true volume was measured with gas pycnometry. Different methods were compared systematically to measure apparent volume, shrinkage and porosity of banana, pineapple and mango slices. Seven methods were tested: liquid pycnometry, liquid displacement and Archimedes principle, with two organic solvents (toluene and n-heptane), and displacement with glass beads. The application of the Archimedes principle with n-heptane to measure specific volume yielded the lowest coefficient of variation for banana and pineapple slices, the second lowest for mango slices, and therefore it was recommended for measuring the apparent volume of fresh and dried fruit samples. All fruit sample during drying showed a reduced degree of shrinkage at the later stage. With the fruit slices shrinking during drying, the specific volume of dried banana, pineapple and mango showed a minimum at approximately 24%, 6% and 30% wb moisture content, respectively. Porosity of banana and mango slices increased 3-folds up to 17% wb and 5-folds up to 12% wb from fresh sample, respectively. Porosity of pineapple increased with moisture content of dried pineapple from around 6% wb to 33% wb, and then kept decreasing till raw pineapple. Image analysis was successfully applicable to measure the diameter and perimeter and describe the structural changes of fruits during drying. [Copyright &y& Elsevier]

Abstract: Kinetic model studies describe quality deterioration rate and their dependence on environmental factors (e.g. temperature and water activity), which are essential for process optimisation. The effect of environmental factors (temperature and relative humidity) on the kinetics of the changes of colour, moisture content and water activity of intermediate moisture content (IMC) banana during storage were investigated. IMC banana samples were stored in the airtight containers with 50–57%, 61–68% and 75–76% relative humidity at 10, 15, 20, 30 and 40°C. Colour and moisture content of samples were monitored over time. The experimental results showed that IMC banana absorbed moisture faster when stored at high temperature and at high relative humidity, at the beginning of storage. The water activity of IMC banana during storage was found to follow an exponential increase, which was described by the lumped capacity model. The zero-order reaction model showed a good fit to the colour (L and ΔE) changes of IMC banana under different relative humidity at 20, 30 and 40°C. A secondary model was developed to describe the changes of L parameter of IMC banana during storage, accounting for the effect of environmental relative humidity and temperatures. Therefore, control of the storage conditions is of great importance to predict and extend the shelf life of IMC banana. [Copyright &y& Elsevier]

• Corncob-based media is a potential option for pigment production by T. atroroseus GH2. • The acid hydrolysis treatment released high xylose yields for culture media design. • Co-utilization of xylose-glucose paves the way to study various agricultural wastes. • Characterized pigments produced by T. atroroseus GH2 differed among evaluated media. • Pigments produced by T. atroroseus GH2 are homologous of Monascus ' pigments. The genus Talaromyces has gained attention due to its ability to produce pigments with potential industrial applications in different areas. Prosperous application of fungal pigments has challenges to overcome, like developing a cost-effective bioprocess. Using agroindustrial wastes could provide inexpensive substrates and it contributes to maximize sustainability. Therefore, this study evaluated the feasibility of using corncob as a low-cost substrate for pigment production by Talaromyces atroroseus GH2. An acid hydrolysis treatment was used to release sugars from corncob. Corncob liquors with enough xylose concentration (>20 g/L) were investigated as fermentation media with and without the addition of nutrients. Process kinetic modeling was applied and pigments produced in corncob and control media were characterized. The diluted hydrolyzate without nutrient supplementation showed a pigment production (16.17±0.37 OD 500nm) comparable to the control medium (17.26±0.41 OD 500nm). Talaromyces atroroseus GH2 was able to co-utilize xylose and glucose in the corncob-based medium. However, growth kinetics patterns differed in both media. In the hydrolyzate medium, biomass growth presented an extended lag phase, which requires reduction for future process optimization. Finally, characterized pigments differed among evaluated media, but the pigments produced by Talaromyces atroroseus GH2 were mostly Monascus ' pigments homologous like monascorubrin and rubropunctamine. Talaromyces atroroseus GH2 ability to produce pigments using corncob hydrolyzate makes it a pigment-producing strain for an economically competitive large fermentation scale. [ABSTRACT FROM AUTHOR]