Multidisciplinary Quality Characterization for the Development of Active and Intelligent Packaging Technologies for Muscle Foods

Fresh food products such as meat and fish are highly susceptible to spoilage. Despite high efforts and advances in food processing and packaging technologies, inevitable microbial activity is the primary reason for their deterioration. Spoilage of muscle foods packaged under modified atmospheres typically manifests itself as changes in the properties of the food product and the surrounding headspace, leading to consumer rejection.Food spoilage is thus a major ecological and economic concern that calls for the development of innovative packaging solutions. These solutions could extend the product’s shelf life by targeting the spoilage microbiota (active packaging) or by providing with realtime information about the product’s quality status (intelligent packaging). Consequently, significant improvement in food quality and decrease of food waste could be foreseen, ultimately benefitting the whole food supply chain.This doctoral dissertation contributes to the development of active and intelligent packaging technologies for muscle foods by means of interdisciplinary quality characterization, involving aspects of packaging material development, food spoilage analysis and multivariate statistical analysis. The main purpose of the dissertation was to define the key aspects of the food quality characterization process within the aforementioned context, to develop novel methods to enhance this process and to address specific research questions about muscle food quality. The theoretical framework and current scientific knowledge is thus reviewed with a focus on the properties and spoilage of muscle foods, the use of silver and oxygen absorbers as well as intelligent packaging concepts. The experimental part of the dissertation describes the materials and methods used for assessing the quality status of meat and seafood packaged under modified atmospheres. The doctoral dissertation is based on four original manuscripts P1-P4 where an antimicrobial releasing system (P1), antimicrobial absorbing system (P2) or quality monitoring principles for an intelligent packaging system (P3-P4) were studied.In the first manuscript (P1), preparation and antimicrobial characterization of silver-containing packaging materials is described. Silver-containing films were produced by coextrusion and liquid flame spraying. Antimicrobial efficiency of the films was examined with bioluminescence imaging as well as with traditional antimicrobial assay. Selected films were used in meat packaging and their impact on the meat microbiota was assessed with chemical, sensory analyses and microbiological analyses, including 16S rRNA sequencing.In the second manuscript (P2), statistical analysis was used for characterizing the impact of high-O2 (80/20/0), common anoxic (0/20/80) and enhanced anoxic (0/20/80 + O2 absorber) atmospheres (O2/CO2/N2 %) on physicochemical properties of pork sirloin. Changes in headspace gas composition (O2/CO2 %), surface pH and color (CIELAB) was monitored as a function of time. Mixed ANOVA was used for determining the effects of storage time, atmosphere and blooming time on the studied variables.In the third manuscript (P3), spoilage of Atlantic cod (Gadus morhua) was examined with microbiological, chemical and sensory analyses. Selected-ion flow-tube mass spectrometry was used for real-time quantification of volatile organic compounds in the package headspace throughout storage time. Cod microbiota was examined with 16S rRNA sequencing.In the fourth manuscript (P4), multivariate statistical analyses were applied for determining potential spoilage indicators of Atlantic cod and brown shrimp (Crangon crangon). Evolution of volatile organic compounds over storage time was explored with hierarchical cluster analysis, principal components analysis and partial least squares regression. Consequently, partial least squares regression was used as a selective tool for identifying most potential spoilage indicators.Results of the present dissertation provide with new insights into the food quality characterization process as well as into the spoilage of packaged muscle food products. The requirements of packaging technology development and the characteristics of food quality information were identified as the main aspects of the characterization process and their impact on the experimental setup and methodology was examined. Efficiency of antimicrobial packaging solutions was found to be highly dependent on food product properties, antimicrobial activity mechanisms and material preparation techniques. Even though nanoscale silver showed high efficiency against typical spoilage bacteria in vitro, they were not effective in situ meat. The impact of varying oxygen levels on pork properties was demonstrated, suggesting that anoxic packaging could have benefits in pork packaging. On the other hand, a systematic procedure was developed for identifying and quantifying volatile organic compounds that could be used as food spoilage indicators. Several compounds were identified as potential spoilage indicators for both Atlantic cod and brown shrimp and their critical concentration levels were defined.Overall, the present dissertation highlights the importance of a multidisciplinary approach and novel methods in food quality characterization when aiming at improving food quality, combining different aspects of microbiology, (bio)chemistry, materials science and multivariate statistical analysis

The constrained median : a way to incorporate side information in the assessment of food samples

A classical problem in the field of food science concerns the consensus evaluation of food samples. Typically, several panelists are asked to provide scores describing the perceived quality of the samples, and subsequently, the overall (consensus) scores are determined. Unfortunately, gathering a large number of panelists is a challenging and very expensive way of collecting information. Interestingly, side information about the samples is often available. This paper describes a method that exploits such information with the aim of improving the assessment of the quality of multiple samples. The proposed method is illustrated by discussing an experiment on raw Atlantic salmon (Salmo salar), where the evolution of the overall score of each salmon sample is studied. The influence of incorporating knowledge of storage days, results of a clustering analysis, and information from additionally performed sensory evaluation tests is discussed. We provide guidelines for incorporating different types of information and discuss their benefits and potential risks

Multivariate statistical analysis for the identification of potential seafood spoilage indicators

Volatile organic compounds (VOCs) characterize the spoilage of seafood packaged under modified atmospheres (MAs) and could thus be used for quality monitoring. However, the VOC profile typically contains numerous multicollinear compounds and depends on the product and storage conditions. Identification of potential spoilage indicators thus calls for multivariate statistics. The aim of the present study was to define suitable statistical methods for this purpose (exploratory analysis) and to consequently characterize the spoilage of brown shrimp (Crangon crangon) and Atlantic cod (Gadus morhua) stored under different conditions (selective analysis). Hierarchical cluster analysis (HCA), principal components analysis (PCA) and partial least squares regression analysis (PLS) were applied as exploratory techniques (brown shrimp, 4 °C, 50%CO2/50%N2) and PLS was further selected for spoilage marker identification. Evolution of acetic acid, 2,3-butanediol, isobutyl alcohol, 3-methyl-1-butanol, dimethyl sulfide, ethyl acetate and trimethylamine was frequently in correspondence with changes in the microbiological quality or sensory rejection. Analysis of these VOCs could thus enhance the detection of seafood spoilage and the development of intelligent packaging technologies.acceptedVersionPeer reviewe

Probabilistic topic modelling in food spoilage analysis : a case study with Atlantic salmon (Salmo salar)

Probabilistic topic modelling is frequently used in machine learning and statistical analysis for extracting latent information from complex datasets. Despite being closely associated with natural language processing and text mining, these methods possess several properties that make them particularly attractive in metabolomics applications where the applicability of traditional multivariate statistics tends to be limited. The aim of the study was thus to introduce probabilistic topic modelling more specifically, Latent Dirichlet Allocation (LDA) in a novel experimental context: volatilome-based (sea) food spoilage characterization. This was realized as a case study, focusing on modelling the spoilage of Atlantic salmon (Salmo solar) at 4 degrees C under different gaseous atmospheres (% CO2/O-2/N-2): 0/0/100 (A), air (B), 60/0/40 (C) or 60/40/0 (D). First, an exploratory analysis was performed to optimize the model tunings and to consequently model salmon spoilage under 100% N-2 (A). Based on the obtained results, a systematic spoilage characterization protocol was established and used for identifying potential volatile spoilage indicators under all tested storage conditions. In conclusion, LDA could be used for extracting sets of underlying VOC profiles and identifying those signifying salmon spoilage, giving rise to an extensive discussion regarding the key points associated with model tuning and/or spoilage analysis. The identified compounds were well in accordance with a previously established approach based on partial least squares regression analysis (PLS). Overall, the outcomes of the study not only reflect the promising potential of LDA in spoilage characterization, but also provide several new insights into the development of data-driven methods for food quality analysis

Characterizing the formation of process contaminants during coffee roasting by multivariate statistical analysis.

peer reviewedCoffee is a relevant source of dietary exposure for neoformed furan, alkyl furans and acrylamide. In this study, different statistical methods (hierarchical cluster analysis, correlation analysis, partial least squares regression analysis) were used for characterizing the formation of these process contaminants in green coffee beans roasted under the same standardized conditions. The results displayed a strong correlation between sucrose levels and furans in relation to the other sugars analyzed, while acrylamide formation was strongly related to the free asparagine. The data suggest that a sufficiently large amino acid pool in green coffee favors Maillard-induced acrylamide formation from asparagine, while reactions amongst the carbonyl-containing sugar fragmentation products leading to furan formation are suppressed. If the pool of free amino acids is small, it is depleted faster during roasting, thus favoring the formation of furans by caramelization, basically a sugar degradation process in which reactive carbonyl substances are generated and react together

Multidisciplinary Quality Characterization for the Development of Active and Intelligent Packaging Technologies for Muscle Foods

Fresh food products such as meat and fish are highly susceptible to spoilage. Despite high efforts and advances in food processing and packaging technologies, inevitable microbial activity is the primary reason for their deterioration. Spoilage of muscle foods packaged under modified atmospheres typically manifests itself as changes in the properties of the food product and the surrounding headspace, leading to consumer rejection.Food spoilage is thus a major ecological and economic concern that calls for the development of innovative packaging solutions. These solutions could extend the product’s shelf life by targeting the spoilage microbiota (active packaging) or by providing with realtime information about the product’s quality status (intelligent packaging). Consequently, significant improvement in food quality and decrease of food waste could be foreseen, ultimately benefitting the whole food supply chain.This doctoral dissertation contributes to the development of active and intelligent packaging technologies for muscle foods by means of interdisciplinary quality characterization, involving aspects of packaging material development, food spoilage analysis and multivariate statistical analysis. The main purpose of the dissertation was to define the key aspects of the food quality characterization process within the aforementioned context, to develop novel methods to enhance this process and to address specific research questions about muscle food quality. The theoretical framework and current scientific knowledge is thus reviewed with a focus on the properties and spoilage of muscle foods, the use of silver and oxygen absorbers as well as intelligent packaging concepts. The experimental part of the dissertation describes the materials and methods used for assessing the quality status of meat and seafood packaged under modified atmospheres. The doctoral dissertation is based on four original manuscripts P1-P4 where an antimicrobial releasing system (P1), antimicrobial absorbing system (P2) or quality monitoring principles for an intelligent packaging system (P3-P4) were studied.In the first manuscript (P1), preparation and antimicrobial characterization of silver-containing packaging materials is described. Silver-containing films were produced by coextrusion and liquid flame spraying. Antimicrobial efficiency of the films was examined with bioluminescence imaging as well as with traditional antimicrobial assay. Selected films were used in meat packaging and their impact on the meat microbiota was assessed with chemical, sensory analyses and microbiological analyses, including 16S rRNA sequencing.In the second manuscript (P2), statistical analysis was used for characterizing the impact of high-O2 (80/20/0), common anoxic (0/20/80) and enhanced anoxic (0/20/80 + O2 absorber) atmospheres (O2/CO2/N2 %) on physicochemical properties of pork sirloin. Changes in headspace gas composition (O2/CO2 %), surface pH and color (CIELAB) was monitored as a function of time. Mixed ANOVA was used for determining the effects of storage time, atmosphere and blooming time on the studied variables.In the third manuscript (P3), spoilage of Atlantic cod (Gadus morhua) was examined with microbiological, chemical and sensory analyses. Selected-ion flow-tube mass spectrometry was used for real-time quantification of volatile organic compounds in the package headspace throughout storage time. Cod microbiota was examined with 16S rRNA sequencing.In the fourth manuscript (P4), multivariate statistical analyses were applied for determining potential spoilage indicators of Atlantic cod and brown shrimp (Crangon crangon). Evolution of volatile organic compounds over storage time was explored with hierarchical cluster analysis, principal components analysis and partial least squares regression. Consequently, partial least squares regression was used as a selective tool for identifying most potential spoilage indicators.Results of the present dissertation provide with new insights into the food quality characterization process as well as into the spoilage of packaged muscle food products. The requirements of packaging technology development and the characteristics of food quality information were identified as the main aspects of the characterization process and their impact on the experimental setup and methodology was examined. Efficiency of antimicrobial packaging solutions was found to be highly dependent on food product properties, antimicrobial activity mechanisms and material preparation techniques. Even though nanoscale silver showed high efficiency against typical spoilage bacteria in vitro, they were not effective in situ meat. The impact of varying oxygen levels on pork properties was demonstrated, suggesting that anoxic packaging could have benefits in pork packaging. On the other hand, a systematic procedure was developed for identifying and quantifying volatile organic compounds that could be used as food spoilage indicators. Several compounds were identified as potential spoilage indicators for both Atlantic cod and brown shrimp and their critical concentration levels were defined.Overall, the present dissertation highlights the importance of a multidisciplinary approach and novel methods in food quality characterization when aiming at improving food quality, combining different aspects of microbiology, (bio)chemistry, materials science and multivariate statistical analysis

Multidisciplinary quality characterization for the development of active and intelligent packaging technologies for muscle foods

Fresh food products such as meat and fish are highly susceptible to spoilage. Despite high efforts and advances in food processing and packaging technologies, inevitable microbial activity is the primary reason for their deterioration. Spoilage of muscle foods packaged under modified atmospheres typically manifests itself as changes in the properties of the food product and the surrounding headspace, leading to consumer rejection.Food spoilage is thus a major ecological and economic concern that calls for the development of innovative packaging solutions. These solutions could extend the product’s shelf life by targeting the spoilage microbiota (active packaging) or by providing with realtime information about the product’s quality status (intelligent packaging). Consequently, significant improvement in food quality and decrease of food waste could be foreseen, ultimately benefitting the whole food supply chain.This doctoral dissertation contributes to the development of active and intelligent packaging technologies for muscle foods by means of interdisciplinary quality characterization, involving aspects of packaging material development, food spoilage analysis and multivariate statistical analysis. The main purpose of the dissertation was to define the key aspects of the food quality characterization process within the aforementioned context, to develop novel methods to enhance this process and to address specific research questions about muscle food quality. The theoretical framework and current scientific knowledge is thus reviewed with a focus on the properties and spoilage of muscle foods, the use of silver and oxygen absorbers as well as intelligent packaging concepts. The experimental part of the dissertation describes the materials and methods used for assessing the quality status of meat and seafood packaged under modified atmospheres. The doctoral dissertation is based on four original manuscripts P1-P4 where an antimicrobial releasing system (P1), antimicrobial absorbing system (P2) or quality monitoring principles for an intelligent packaging system (P3-P4) were studied.In the first manuscript (P1), preparation and antimicrobial characterization of silver-containing packaging materials is described. Silver-containing films were produced by coextrusion and liquid flame spraying. Antimicrobial efficiency of the films was examined with bioluminescence imaging as well as with traditional antimicrobial assay. Selected films were used in meat packaging and their impact on the meat microbiota was assessed with chemical, sensory analyses and microbiological analyses, including 16S rRNA sequencing.In the second manuscript (P2), statistical analysis was used for characterizing the impact of high-O2 (80/20/0), common anoxic (0/20/80) and enhanced anoxic (0/20/80 + O2 absorber) atmospheres (O2/CO2/N2 %) on physicochemical properties of pork sirloin. Changes in headspace gas composition (O2/CO2 %), surface pH and color (CIELAB) was monitored as a function of time. Mixed ANOVA was used for determining the effects of storage time, atmosphere and blooming time on the studied variables.In the third manuscript (P3), spoilage of Atlantic cod (Gadus morhua) was examined with microbiological, chemical and sensory analyses. Selected-ion flow-tube mass spectrometry was used for real-time quantification of volatile organic compounds in the package headspace throughout storage time. Cod microbiota was examined with 16S rRNA sequencing.In the fourth manuscript (P4), multivariate statistical analyses were applied for determining potential spoilage indicators of Atlantic cod and brown shrimp (Crangon crangon). Evolution of volatile organic compounds over storage time was explored with hierarchical cluster analysis, principal components analysis and partial least squares regression. Consequently, partial least squares regression was used as a selective tool for identifying most potential spoilage indicators.Results of the present dissertation provide with new insights into the food quality characterization process as well as into the spoilage of packaged muscle food products. The requirements of packaging technology development and the characteristics of food quality information were identified as the main aspects of the characterization process and their impact on the experimental setup and methodology was examined. Efficiency of antimicrobial packaging solutions was found to be highly dependent on food product properties, antimicrobial activity mechanisms and material preparation techniques. Even though nanoscale silver showed high efficiency against typical spoilage bacteria in vitro, they were not effective in situ meat. The impact of varying oxygen levels on pork properties was demonstrated, suggesting that anoxic packaging could have benefits in pork packaging. On the other hand, a systematic procedure was developed for identifying and quantifying volatile organic compounds that could be used as food spoilage indicators. Several compounds were identified as potential spoilage indicators for both Atlantic cod and brown shrimp and their critical concentration levels were defined.Overall, the present dissertation highlights the importance of a multidisciplinary approach and novel methods in food quality characterization when aiming at improving food quality, combining different aspects of microbiology, (bio)chemistry, materials science and multivariate statistical analysis