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To develop an activebiopolymerfilm based on chitosan, sodium caseinate, and rosemary essential oil (REO), the objective of this work was to investigate the effect of REO on the structure and physical properties of biopolymer films.Fourier transform infrared spectroscopywas conducted for fingerprinting to identify the REO addition. The thermal behaviour of each film was investigated using athermogravimetric analysis. Furthermore, the optical properties, surfacehydrophobicity, solubility, mechanical properties, and water vapour permeability were investigated. The results showed that the presence of REO changes the structural organisation of the blended sodium caseinate and chitosan film, thereby inducing an increase in the surface hydrophilicity of the film. However, the solubility and water vapour permeability of the film were not affected by the structural modification induced by REO. Moreover, a mild effect of the REO on the mechanical properties of the sodium caseinate/chitosan film was observed. A thermal analysis confirmed that the incorporation of REO did not influence the degradation temperature of the films. Overall this studying has demonstrated that caseinate/chitosan film enriched in REO, related to his thermal and chemico physical properties can be applied for food packaging application.

This work was aimed to study the implication of different sensory methodologies (an analytical method by selected assessors, and two hedonic methods: Acceptability limit and Survival analysis), for determining the shelf-life of a pumpkin-orange cake. Hedonic methods were performed by two groups of consumers: group A performed acceptability test first, and then survival analysis, for the group B the order was reversed. Indeed, the survival analysis was also assessed by using a staggered design and by involving other consumers. By considering the results of both analytical method and hedonic method performed by group A, the estimated shelf-life was about 15 days, meanwhile, it ranged from 30 to 40 days, based on the results of hedonic methods performed by group B of consumers and the results of survival analysis performed by using the staggered design. Failure criteria based on consumer acceptability must therefore be accurately chosen to avoid shelf-life estimation that does not reflect consumer behavior. The combination of two sensory methodologies could be a fast way to get more information regarding both the acceptability and the reason why the consumers will accept or reject the product.

Iceberg lettuce (Lactuca sativa L.) is a highly perishable product and it is considered one of the most popular minimally processed vegetables. Commercially available iceberg lettuce has a short shelf-life of 7 days at 7°C. Enzymatic browning is one of the main factors affecting product shelf life when oxygen is present in the packaging system. For this purpose, the aim of this work was (i) to investigate the decay kinetics of minimally processed iceberg salad following polyphenols and browning index evolution at different temperature (4°C, 8°C, 12°C); (ii) to evaluate the effect of salicylic acid on enzymatic browning. Minimally processed iceberg samples were stored at 4°C, 8°C, 12°C in air for 14 days. Samples treated with salicylic acid were stored at 8°C for 14 days. Polyphenols and browning index were evaluated by spectrophotometric analysis. The kinetics constant and activation energy (Ea) has been calculated by non-linear regression. The enzymatic browning was well described by a pseudo first order kinetic. The kinetic constant at reference temperature (8°C) was 0.00948 h-1 for polyphenols decay and 0.0184 h-1 for browning index. Ea for polyphenols and browning index were 83.21 kJ/mol and 63.49 kJ/mol, respectively. Salicylic acid showed a significant effect on enzymatic browning kinetic by delaying the evolution of the reaction during the first days of storage.

The objective of this work was to study the oxidation of fresh meat hamburger by selecting the critical quality index of lipid oxidation and quantifying the kinetics of alteration of red meat oxidation. Meat hamburger were stored at 4°C and 10°C for 21 and 17 days respectively. The following quality index were monitored: pH, color (L*, a*, b*), secondary lipid oxidation (TBARS test), and metmyoglobin percentage (Metmio%). Results showed that among quality indices the colorimetric parameter a* and MDA were the only ones able to discriminate samples as function of time, atmosphere and temperature.

Ready-to-Use Therapeutic Foods (RUTFs) have to recover health status of malnourished children without clinical complications. If produced in loco, RUTFs should be stable when stored at room temperature and unprotected atmosphere. The aim of this work was to verify the oxidative stability of 4 RUTFs, by means of conjugated dienes and malondialdehyde (MDA) content at 3 temperatures for 4 weeks. RUTFs initially presented a different content of peroxydiene and their increase was well described by pseudo zero order models. Kinetic constants at 60°C were higher than those estimated at 30° and 40°C. MDA values were very low (≈0.48 µg/ml after 4 weeks). Those products were quite stable over 2 weeks even if stored at 40°C in an unprotected atmosphere.

The effect of biopolymer coatings (1% chitosan, 2% chitosan, caseinate/chitosan blend at ratio 2/1) in combination with anti-browning agent (1% citric acid, 1% l-ascorbic acid agents, 1% CaCl2) on the shelf life of minimally processed apples was studied. The experimental works were divided in two phases: in the first phase, the coating composition has been selected on the bases of microstructural analysis of the coatings on the fruit surface (SEM), respiration rate, water resistance, and color. In the second phase of the study, the shelf life of packed minimally processed apples coated with the selected coating was studied during storage at 5 degrees C. The uncoated sample dipped in anti-browning solution was used as control. The following quality attributes were monitored after 1, 3, 7, 11 and 14 days: pH, hardness, relative humidity (RH %) and color. All coatings effectively reduced respiration rate of minimally processed apples but only caseinate/chitosan one was not significantly different from the control sample in terms of color attributes (p

The secondary shelf life of croissants made by frozen dough was estimated by using the survival analysis methodology. Check-all-that-apply (CATA) questions were also performed in order to evaluate sensory perception of the product by consumers. Two formulations of frozen butter croissant (A, B) were stored at -18 degrees C until experimental analysis. The samples were removed from the freezer and baked for 20 minute at 180 degrees C. Samples were stored for 3, 7, 16, 20, 23 and 27 hours at 25 degrees C and 65% of relative humidity (RH). Ninety-six subjects participated in the consumer test. They were asked to eat each sample, and answer the question:" Would you normally consume/buy this croissant? Yes or No?" and provide a sensory product characterization using check-all-that-apply (CATA) questions composed of 16 terms. Results showed that the survival analysis can be used to successfully determine the secondary shelf life of croissants. Weibull distribution was used to describe the rejection function. The shelf life was estimated as the storage time that corresponded to 50% consumers rejection in 22 +/- 2 h and 11 +/- 2 h, respectively for formulation A and B. Significant differences among samples were found in terms of both negative (stale, hard, dry) and positive (soft, fresh) attributes, and, as expected, frequency of use of the positive attributes decreased with storage time, whereas the contrary occurred for the negative ones.

This work is part of a project aimed at exploiting the edible part of bluefin tuna scrap by using them to produce fish burgers. The objective of the work was the optimization of bluefin tuna fishburger MAP by means of a mixture design and a triangular surface analysis. As dependent variable tuna fish burger colour (chromatic coordinate a*) was used. A linear constraints design was chosen and vertex and centroid points were selected (D optimal design). A quadratic model was selected as the most appropriate to fits the dependent variable response surfaces. The fat oxidation was also studied. Results of this preliminary work showed that, starting from tuna processing wastes, it can be realized a minimally processed seafood, as tuna fish burger. Mixture design and triangular surface analysis can be a good tools for gas composition optimization. High oxygen concentration and high level of carbon dioxide seems to prolong the product shelf life up to 9 days at 3°C.

A mathematical model was developed in order to describe the effect of temperature on the degradation process of shredded carrots. Shredded carrots were stored in an air flux system in the range of temperature 0 degrees-20 degrees C. Storage time varied with temperature to observe the complete decay of pH and colour over time. The experimental data collected at 10 degrees C were used to validate the model. The evolution of the pH over time was reasonably well describes by a Weibull equation, while a first order equation described the colour change. The rate constants of both models varied with temperature according to an Arrhenius - type relationship with activation energy equal to 71 +/- 2 KJ/mol for the pH, and 89 +/- 5 KJ/mol for the colour.

The objectives of this work were (i) to identify the sensory attributes of "Altamura" focaccia that change during storage time, by using the check-all-that-apply (CATA) questions, and (ii) to understand which attributes significantly drive the consumer's liking. Sensory tests were conducted on three different focaccia samples at 7, 22, 40 and 55 days of storage. Results showed that frequency of use of positive attributes decreased with storage time, whereas the contrary occurred for negative ones. The positive attributes that affected consumer's liking belonged to both texture properties of the base and flavor properties of the topping.

The objective of the work was to identify the quality indices of lipid oxidation of Grana Padano cheese and to optimize the methods for their determination. Cheese was stored at 4°C and at 20°C for 60 days. Free fatty acids (FFA) content, peroxide value (PV) and volatile organic compounds (VOC) were studied during storage. No difference for FFA values in cheese during the storage was found, while PV increased after 60 days at 20°C. The concentration of VOC increased during the storage. Results showed that VOC were the best quality indices to discriminate samples during storage.

The objective of the work was to improve the physical properties of caseinate (SC)-based coating by using a thickening agent, guar gum (GG), and a solid fat phase, beeswax (BW). To this aim, the effect of GG, BW, and surfactant concentration, varying the hydrophilic-lipophilic balance (HLB) values given by surfactant combination, on the physicochemical properties of the caseinate-based blends and film has been investigated. The best formulation has been applied to strawberries to quantify the impact of the coating on respiration and transpiration rates. The results showed that GG, BW, their interaction, and HLB affected the physical properties of the sodium caseinate-based coating. The formulations most physically stable and containing small and uniform solid BW particles were those with an HLB of 9.2. GG affected the viscosity of the blends, whereas the effect of beeswax concentration on viscosity was very low. A 50% of reduction of water vapor permeability was obtained by changing GG and BW concentration. The best formulation, containing 8% SC, 0.2% GG, 2% BW, and Tween 80 and Span 80 at HLB of 9.2, was able to reduce the respiration and transpiration rates of strawberries by 17% and 40%, respectively, at 4 °C and relative humidity higher than 86%.

Fruits and vegetables (F&V) products are recommended for the daily diet due to their low caloric content, high amount of vitamins, minerals and fiber. Furthermore, these foods are a source of various phytochemical compounds, such as polyphenols, flavonoids and sterols, exerting antioxidant activity. Despite the benefits derived from eating raw F&V, the quality and safety of these products may represent a source of concern, since they can be quickly spoiled and have a very short shelf-life. Moreover, they may be a vehicle of pathogenic microorganisms. This study aims to evaluate the bacterial and fungal populations in F&V products (i.e., iceberg lettuces, arugula, spinaches, fennels, tomatoes and pears) by using culture-dependent microbiological analysis and high-throughput sequencing (HTS), in order to decipher the microbial populations that characterize minimally-processed F&V. Our results show that F&V harbor diverse and product-specific bacterial and fungal communities, with vegetables leaf morphology and type of edible fraction of fruits exerting the highest influence. In addition, we observed that several alterative (e.g., Pseudomonas and Aspergillus) and potentially pathogenic taxa (such as Staphylococcus and Cladosporium) are present, thus emphasizing the need for novel product-specific strategies to control the microbial composition of F&V and extend their shelf-life.

A coupled experimental and modelling approach was developed to characterize the radical inhibition and oxygen scavenger properties of gallic acid/ sodium carbonate mixture included in a PHBV film. PHBV active packaging was produced by thermoforming. In contact with acqueous and fatty food simulants, almost 30% of the initial gallic acid was released into food simulants A (10% ethanol), and D1 (50% ehtanol), where it showed a radical inhibition value (I%) reaching 68 ± 0.1% and 77 ± 0.1% respectively, while no release was observed in food simulant D2 (isooctane). In addition, the active films displayed an O2 scanvenger capacity of 120 mg O2 g−1 GA at room temperature, after 10 days of storage. Models showed a good fitting to experimental data. The PHBV active packaging combining both antiradical and oxygen scavenger activities has high potential for food protection. However, some improvements are still needed to enhance its oxygen barrier capacity and to meet the reglementation.

Background To establish bioplastics as a real alternative to conventional plastics, high production costs must be constrained by using different kinds of wastewater streams as organic substrates and novel microbial strains as material-accumulating bacteria with high performance. Volatile fatty acids (VFAs) from the effluent of dairy wastewater biodigestion represent a new and inexpensive feedstock, which was used in this study for biopolymer production through microbial processes. Results Cupriavidus necator DSM 13513 was particularly able to accumulate PHAs when operating in fed-batch mode by limiting the oxygen level together with intermittent feeding of a carbon source; maximum poly-β-hydroxybutyrate (PHB) accumulation was achieved in 48 h without compromising microbial growth. The complex VFAs mixture from the digestate did not influence PHA homopolymer accumulation. In fact, structural characterization by NMR analysis revealed PHB synthesis by C. necator DSM 13513 grown with different VFAs mixtures. Moreover, the bioplastic disk obtained from C. necator DSM 13513 cells grown on VFAs from digested dairy wastewater effluent presented good thermic properties and low affinity to water. Conclusions Overall, the results make digested dairy wastewater effluent suitable for PHB production for specific biobased industrial applications.

The objective of this work was to investigate the effect of sodium caseinate concentration on physical-chemical properties of coating solutions and films obtained by casting as a starting point for the development of an active coating for minimally processed fruits or vegetables. Sodium caseinate solutions at different concentrations (4%, 8%, 10%, 12%, 14%) were used as a coating system. The coating viscosity and desorption kinetic were characterized. Minimally processed fennels were coated by dipping and the liquid and dry coating thickness were estimated by assessing the amount of coating on fennel during draining as a function of solution properties (concentration and viscosity). Film obtained by casting were also characterized in terms of equilibrium moisture content, color, and water vapor permeability. The potential of using the sodium caseinate solution to obtain active coating was investigated by adding gallic acid or rosemary oil to sodium caseinate solution at 4%. The antioxidant capacity of the coating was evaluated by DPPH test. Results show that sodium caseinate solutions follow a Newtonian behavior in the range of concentration investigated and the viscosity increased as solids concentration increased, following a power law. The drying rate was in the range 0.0063&ndash, 0.00107 mgH2O&middot, mgsolids&minus, 1&middot, min&minus, m&minus, 2 as a function of sodium caseinate concentration. The average liquid and dry coating thickness on fennels were in the range 20&ndash, 70 and 0.7&ndash, 6.4 &mu, m, respectively. The water vapor permeability slightly decreased as the solid concentration increased. Active coating showed good antioxidant properties.

Minimally processed F&V while being as fresh as the intact product, are characterized by an accelerated produce decay which affects its nutritional value during shelf-life. In this sense, food processing needs to further evolve in terms of better preservation of nutritional properties. Active packaging technology has shown positive and promising results to maintain safety and sensory properties of minimally processed F&V. This review aims to present the recent research results regarding biopolymeric antioxidant film and coating for preservation of nutritional quality of minimally processed F&V. The mechanism by which nutritional losses (around 5–30 % loss of ascorbic acid and phenolic compounds) occur from oxidation reactions in F&V and natural antioxidant have been discussed. Furthermore, regulatory aspects related to antioxidant packaging have been also reported. Biopolymers based antioxidant film and coating have been vastly used to pack F&V product. Chitosan, gelatin, casein and alginate were found to be more effective as packaging materials (both as coating and as film) to preserve the nutritional and sensory quality of F&V product. Furthermore, plant extracts (green tea and Aloe vera), essential oils (lemon grass), plant oil compounds (eugenol and citral) and phenolics (thymol) as a component of active film or coating systems have shown promising results in preserving the quality of fresh produce. The collected findings will be useful to accurately design an innovative active film or coating for nutritional quality preservation of minimally processed fresh fruits and vegetables.

There is an urgent need to increase the food supplies to fulfil the demands of future generations as the population of the world is expected to grow beyond 10 billion by 2050. An essential component for ensuring global food security is to reduce food losses during the post-harvest stage. Active edible coatings and films are a promising sustainable preservation technology for shelf-life extension of food products by hindering decay kinetics of minimally processed fruits and vegetables (F&V), by restricting the mass transfer of moisture, aroma, or gases and carrying an active compound, such as an antioxidant or antimicrobial. Active protein-based coatings and films have the potential to extend the shelf-life of food products by decreasing their respiration rates, as they exhibit an excellent gas barrier and good mechanical properties as compared to other biopolymeric packaging. Among protein-based biopolymers, casein and its derivatives as packaging films have been extensively studied due to their low cost, complete biodegradability, and availability. Currently, there is no review study focusing on caseinate-based active coating and film, thus, this review aims to give insights on the composition, rheology, structure, and properties of caseinate-based formulations by critically discussing the results presented in the literature. A methodological approach was followed to obtain relevant literature to discuss the influence of additives on the shelf-life of F&V. Furthermore, changes in secondary structure of casein were observed after incorporation of bioactive compounds (i.e., phenolic acids). Likewise, there is a need to explore chemical interactions among bioactive compounds and biopolymer material by using in silico and laboratory trials as food additives have shown to influence the physicochemical properties of film and shelf-life of food products.

New antioxidant polyamide was prepared by total immersion in active extract for 48 h. Its antioxidant performance was tested using DPPH (IC50 = 270 ± 21 μg/g) and ORAC (1.52 µmol Trolox/g). In vivo study was done using fresh minced meat stored at 4 °C and analysed after 0, 6, 13, 19, 23 days. After 23 days metmyoglobin (MetMbBK = 31.3 ± 2.9% and MetMbAOX = 25.9 ± 0.8%), CIE L*a*b* (a*BK = 15.0 ± 0.4 and a*AOX = 16.6 ± 0.3) and TBARS (MDABK = 0.0060 ± 0.0003 µg/g and MDAAOX = 0.0044 ± 0.0002 µg/g) showed an improvement of meat shelf life. The results showed that this active film protected meat during 23 days. Migration study to food simulants was done by UPLC®-QqQ-MS and UPLC®-ESI-Q-TOF-MSE. A decrease of oligomers migration (for caprolactam n = 3: BK = 0.050 ± 0.004 mg/Kg; AOX = 0.019 ± 0.001 mg/Kg) was found. Industrial relevance Nowadays, food industry is focused on improving shelf life of products by controlling its lipid oxidation using natural antioxidants. The obtained results let us design a new active packaging based on natural antioxidants for extending the shelf life of fresh minced meat at industrial scale.

The effect of caseinate/chitosan blend on the shelf life of minimally processed apples was studied. In the first phase of the work, the effect of the biopolymer coating on the respiration rate of the minimally processed apples was studied as function of gas composition (5%, 10%, 21% of O2 with N2 as balance at 5 &deg, C) and temperature (5 &deg, C, 10 &deg, C at 5% of O2 with N2 as balance). In the second phase, the shelf life of the packed product was studied during storage at 5 &deg, C. The gas composition (O2%-CO2%) in the package headspace, relative humidity, pH, hardness, color and antioxidant capacity of the product were monitored after 0, 1, 4, 7, 11, and 14 days. The coating effectively reduced respiration rate of the product when oxygen was over 10%. In the presence of the coating, the reduction of oxygen did not affect the respiration rate. At 5% of O2, the respiration rate decreased by 50% by changing the temperature from 10 &deg, C to 5 &deg, C. Shelf life study showed that the chitosan&mdash, caseinate coating was able to preserve the mechanical properties and the antioxidant capacity of the product during storage by increasing the shelf life by 7 days to 11 days at 5 &deg, C.

Shelf life can be defined as the finite length of time after which the product stored under specific packaged and environmental condition becomes unacceptable. A description of the main steps to study food shelf life and to define it based on simulation tests is reported. The first part of the article describes the main processes responsible for deterioration of food and the main critical quality parameters related to product or environmental. Then, the main quality indexes and how to determine the critical value of the quality index to establish the end of the shelf life are described. In the last part of the article, how to implement a shelf life study is described.

The objective of the work was to study the viability and antimicrobial activity of bacteriocin-producing lactic acid bacteria (LAB) incorporated into whey protein/inulin/gelatine (WP) edible films in presence or absence of nutrient (modified MRS broth). Moreover, the role of the cell on the film structure and properties has been investigated. The results of the work showed that WP-based films were able to ensure a high viability of the bacteriocin-producing strain L. curvatus 54M16 during 28 days of storage at 4 °C. The addition of nutrient in the film matrix slightly affected the viability of the cells, but it was critical for the antimicrobial activity of the films. Films in presence of nutrient showed a good antimicrobial activity against L. innocua C6 as in vitro system as on cooked ham. The presence of LAB has a significant effect on the structure of the film: it reduced the viscosity of the film forming solution and improved the elasticity and the percentage of elongation. Whereas, no effect was observed for water vapour transmission rate and solubility. Thus, WP-based films in presence of modified MRS broth can be used as effective delivery and carrier systems for lactic acid bacteria to develop bioactive edible film or coating with antimicrobial properties.