Orientador: Mirna Lúcia Gigante / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T11:42:02Z (GMT). No. of bitstreams: 1 Dias_MariaElisabeteFernandesDias_M.pdf: 5400605 bytes, checksum: 00a236017885ffd7ef50a95f530931bb (MD5) Previous issue date: 2011 / Resumo: O objetivo deste trabalho foi avaliar o efeito da adição de CO2 ao leite cru sobre as características do leite UHT obtido por injeção direta de vapor e armazenamento a 25ºC, 35ºC e 45ºC por 180 dias. O leite cru (250 litros) foi dividido em duas porções que foram armazenadas em tanques de expansão a 4?1ºC por seis dias. Uma porção foi adicionada de CO2 grau alimentício até que o pH do leite atingisse 6,20, enquanto a outra serviu de controle. O leite cru foi avaliado quanto ao pH, acidez, prova do álcool, composição físico-química, proteólise, lipólise, cor e concentração de CO2 após a injeção. Para caracterização microbiológica, o leite cru foi avaliado quanto à contagem padrão em placas e de micro-organismos psicrotróficos no dia da recepção e após seis dias de armazenamento refrigerado. As amostras foram submetidas ao tratamento UHT por injeção direta de vapor (143ºC/4s), envasadas em embalagens tetra brik asseptic de 125 ml e armazenadas em BOD a 25, 35 e 45 ºC por 180 dias. No dia seguinte, as amostras foram avaliadas quanto as mesmas características do leite cru, além da prova do álcool, viscosidade, sedimentação, eletroforese, peptídeos por HPLC e esterilidade comercial. Após 1, 30, 60, 90, 120, 150 e 180 dias de armazenamento, as amostras foram avaliadas quanto ao pH, acidez, nitrogênio e frações nitrogenadas, cor, ácidos graxos livres, sedimentação, viscosidade, eletroforese e peptídeos por HPLC. O delineamento experimental foi o de sub-sub-parcelas divididas e o experimento foi repetido três vezes. O efeito do tratamento, da temperatura e do tempo de armazenamento, e a interação destes fatores sobre as características do leite UHT foi avaliado por análise de variância (ANOVA) e teste de Tukey ao nível de 5% de significância. Após seis dias de armazenamento refrigerado, não houve diferença significativa nas características físico-químicas do leite adicionado ou não de CO2, exceto na quantidade de ácido graxos livres que foi maior no leite controle do que no adicionado de CO2. A adição de CO2 inibiu o desenvolvimento de micro-organismos durante o armazenamento refrigerado, uma vez que a contagem total e de psicrotróficos do leite controle foi maior que as contagens do leite adicionado de CO2 . O pH das amostras de leite UHT armazenadas a diferentes temperaturas foi afetado pela temperatura e pelo tempo de armazenamento, apresentando maior decréscimo do pH nas amostras armazenadas a 45 ºC. A cor das amostras a 25°C não apresentou escurecimento durante os 180 dias, enquanto as armazenadas a 35°C e 45°C apresentaram desenvolvimento de cor visível a olho nu e aumento no valor b* ao longo do tempo. A lipólise do leite UHT foi maior nas amostras armazenadas a 45ºC. A proteólise foi maior no leite armazenado a 45°C, cujo aumento não refletiu na viscosidade e sedimentação do leite, que não foram significativamente afetados até o 120° dia de armazenamento, prazo de validade usualmente garantido pelas indústrias de processamento de leite UHT no Brasil / Abstract: The objective of this study was to evaluate the effect of CO2 addition to raw milk on the characteristics of UHT milk obtained by direct steam injection and stored at 25 ° C, 35 ° C and 45 ° C for 180 days. Raw milk (250 liters) was divided in two portions that were stored in bulk tanks at 4 ± 1 ° C for six days. To one portion was added food grade CO2 until the pH of milk was 6.20, while the other portion was the control sample. Raw milk was evaluated for pH, acidity, physicochemical composition, proteolysis, lipolysis, color and concentration of CO2 after injection. Raw milk was evaluated for standard plate count and psychrotrophic micro-organisms on the reception and after six days of cold storage, for microbiological characteristics. The samples were submitted to UHT treatment by direct steam injection (143°C/4s), packed in 125 ml Tetra Brik Asseptic packing and stored in BOD at 25, 35 and 45 ° C for 180 days. One day after processing, the samples were evaluated for the same characteristics of raw milk, plus alcohol stability, viscosity, sedimentation, electrophoresis, peptides by HPLC and commercial sterility. After 1, 30, 60, 90, 120, 150 and 180 days of storage, samples were evaluated for pH, acidity, nitrogen and nitrogen fractions, color, free fatty acids, sedimentation, viscosity, electrophoresis and peptides by HPLC. The experimental design was split-split-plot and the complete experiment was repeated three times. The effect of treatment, temperature and storage period as well as the interaction of these factors on the characteristics of UHT milk was assessed by analysis of variance (ANOVA) and Tukey¿s test at 5% significance level. After six days of cold storage, there was no significant difference in the physicochemical characteristics of raw milk with or without CO2 addition, except for free fatty acid values, which were higher for the milk without CO2 addition. The addition of CO2 inhibited the development of microorganisms during storage, since the standard plate count and psychrotrophic count of milk control was higher than values for the CO2 added milk. The pH of UHT milk samples was affected by temperature and storage time, showing greater decrease in pH for samples stored at 45°C. The color of the samples at 25°C showed no browning during the 180 days, while those stored at 35 ° C and 45 ° C showed brown color visible to the naked eye and an increased b * value over time. Lipolysis of UHT milk samples was higher for samples stored at 45°C. The proteolysis was higher in milk stored at 45°C, whose increase was not reflected in viscosity and sedimentation of the milk, since these parameters were not significantly affected during 120 days-storage, period of shelf life usually guaranteed by the processing industries of UHT milk in Brazil / Mestrado / Tecnologia de Alimentos / Mestre em Tecnologia de Alimentos

Orientador: Vivaldo Silveira Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T09:55:48Z (GMT). No. of bitstreams: 1 Lage_BrunadeCarvalhoFonseca_M.pdf: 7834171 bytes, checksum: 9781ad0b393f78deff771c5484867e54 (MD5) Previous issue date: 2012 / Resumo: Os consumidores têm se mostrado cada vez mais exigentes em relação aos alimentos, na busca de produtos de fácil preparo, e que, também, reúnam qualidades sensoriais e nutricionais. A técnica sous vide consiste em pasteurizar produtos alimentícios embalados a vácuo, de modo que o tratamento térmico mais brando minimize a destruição de nutrientes sensíveis ao calor e a embalagem hermética previna perdas de compostos voláteis responsáveis pelo sabor. O rápido resfriamento após o tratamento térmico e a estocagem sob refrigeração aumentam a vida útil do produto. O pescado é, em geral, um alimento muito perecível, quando comparado com outros alimentos in natura, portanto, as indústrias podem ter uma expansão de mercado ao ter um processamento que consiga manter a qualidade desses produtos por mais tempo. Neste contexto, este trabalho teve como objetivo avaliar as condições de tempo e temperatura do tratamento térmico no processo sous vide de salmão (Salmo salar), bem como acompanhar algumas características do produto durante a sua vida útil. Para isso, foi montado um equipamento termocirculador e ensaiadas porções de 150 g de salmão, as quais foram submetidas a um tratamento térmico de acordo com um planejamento experimental. Os resultados mostraram que os produtos processados com temperaturas mais altas apresentaram textura mais firme e os parâmetros de cor L* aumentou e C* diminuiu, tornando mais clara a coloração do peixe. Porém, não foram identificadas mudanças nessas características ao longo do tempo de estocagem. Os valores de pH não mostraram variação e as amostras apresentaram baixo índice de oxidação lipídica. Conforme o resultado das análises microbiológicas verificou-se que os tratamentos com temperaturas iguais ou inferiores a 50°C não foram suficientes para garantir a segurança do produto por 21 dias de armazenagem. Propôs-se uma correlação de tempo/temperatura (degree-time) com o período de estocagem para estimativas em outras condições de processo / Abstract: Nowadays, consumers are more and more demanding concerning food, seeking to easy cooking food, which also should have sensorial and nutritional qualities. The sous vide technique entails in to pasteurize vacuum-packed food so that, a mild thermal treatment will avoid the destruction of nutrients that are sensitive to heat, and also, the hermetic packing should prevent loss of the volatile substances responsible for the taste. The fast cooling after thermal treatment and the refrigerated storage will increase the shelf life of the product. Fish product is in general, very perishable, compared to other foods in natura, therefore, industries can have their markets improved by having a processing that keep the qualities of these products even longer. In this context, this work aims to evaluate thermal treatment conditions in time/temperature of the salmon (Salmo salar) in the sous vide process, as well to follow some characteristics from the product during its shelf life. For that, a bath tank was assembled and portions of 150 g of salmon, which were submitted to a thermal treatment, according to an experimental design. The results showed that, the products that were processed in higher temperatures, presented firmer texture and the color parameters L* increased and the C* decreased, making the color of the fish lighter. However, changes haven?t been identified in those characteristics during storage. The pH values haven?t shown variation and, the samples have shown lower oxidation levels. According the result of microbiological analysis, it was noted that treatment with temperatures equal or under 50º C don?t assure the safety of the product for 21 days of storage. A degree-time correlation with shelf life was suggested for further calculations in different process conditions / Mestrado / Engenharia de Alimentos / Mestra em Engenharia de Alimentos

A demanda por frutas e hortaliças frescas, associada à necessidade de maior praticidade da vida atual, está incentivando o interesse dos consumidores por produtos minimamente processados. Entre os microrganismos patogênicos que podem ser transmitidos por estes vegetais encontram-se principalmente Listeria monocytogenes, Escherichia coli O157:H7 e Samonella spp. Alguns métodos são utilizados para prevenir e controlar estes microrganismos, entre eles, a irradiação. Amostras de agrião (Nasturtium oficinallis) minimamente processado foram inoculadas com uma mistura de três cepas de Salmonella (Salmonella Infantis, Salmonella Enteritidis ATCC 13076, Salmonella Tiphymurium ATCC 14028) e expostos às doses de 0; 0,2; 0,5; 0,7; 1,0; 1,2 e 1,5 kGy. O valor D10 para Salmonella spp inoculada em agrião minimamente processado submetido à radiação gama variou de 0,29 a 0,43 kGy. Amostras de agrião expostas a doses de 1, 3 e 4 kGy e amostra testemunha, mantidas sob refrigeração, foram utilizadas para avaliação sensorial e vida-de-prateleira. Todas as amostras expostas à radiação foram aceitas pelos julgadores. A vida-de-prateleira da amostra de agrião exposta à 1 kGy foi de 16 dias, um dia e meio a mais que a testemunha. A vida-de-prateleira das amostras expostas à 3 e 4 kGy foi de 9 e 6 dias, respectivamente. / Consumer attitudes towards foods have changed in the last two decades increasing requirements for freshlike products. Consequently less extreme treatments or additives are being required. Minimally processed foods have freshlike characteristics and satisfy this new consumer demand. Besides freshness, the minimally processing also provide convenience required by the market. Salad vegetables can be source of pathogen such as Salmonella, Escherichia coli O157:H7and Listeria monocytogenes. The minimally processing does not reduce the levels of pathogenic microorganisms to safe levels. Therefore, this study was carried out in order to improve the microbiological safety and the shelf-life of minimally processed vegetables using gamma radiation. Minimally processed watercress inoculated with a cocktail of Salmonella spp was exposed to 0.0, 0.2, 0.5, 0.7, 1.0, 1.2 and 1.5 kGy. D10 values for Salmonella spp inoculated in watercress varied from 0.29 to 0.43 kGy. Samples of watercress exposed of 1, 3 e 4 kGy and non-irradiated sample, stored at 7°C, were submitted to sensory evaluation and their shelf-life was determined. All samples were accepted by members of sensory panel. The shelf-life of sample irradiated with 1 kGy was 16 days (one and half day more than shelf-life of non-irradiated sample) and samples exposed to 3 and 4 kGy presented shelf-life of 9 and o days, respectively.

A cebola (Allium cepa L.) é uma das plantas de maior difusão do planeta e apresenta grande importância mundial, não só em termos de produção, mas também de consumo. No Brasil, é a terceira hortaliça mais cultivada e seu consumo é feito principalmente in natura como condimento ou tempero. Os produtos minimamente processados vêm obtendo crescente participação no mercado de produtos frescos em função da praticidade que oferecem ao consumidor. No caso da cebola, o preparo do bulbo é o maior motivo de reclamações, já que por conter compostos voláteis causam irritação aos olhos e deixam odor característico na mão do manipulador. Seu processamento mínimo poderá aumentar seu consumo e ainda alcançar novos mercados por todo o País. Entretanto, para que isso ocorra é preciso estudar a fisiologia e o manuseio específico dessa hortaliça, de forma a compreender as principais alterações que ocorrem, além de métodos que possam reduzir mudanças que acelerem sua deterioração. Este trabalho teve como objetivo avaliar os aspectos bioquímicos, fisiológicos e microbiológicos da cebola roxa minimamente processada, utilizando diferentes temperaturas de armazenamento, combinadas com dois tipos de corte, e, posteriormente, diferentes embalagens, a fim de prolongar sua vida útil. No primeiro experimento foram testadas quatro temperaturas de armazenamento, 0, 5, 10 e 15°C, e dois tipos de cortes, cubos (10 mm aresta) e fatias (3-5 mm espessura), por 15 dias a 85-90% UR. No segundo, o corte que teve o melhor desempenho foi utilizado para testar diferentes embalagens: recipiente de polipropileno (PP), filme de cloreto de polivinila (PVC - 14 ?m), filme de PP (10 ?m) e filme de polietileno de baixa densidade (PEBD - 10 ?m). As cebolas foram armazenadas a 5°C e 85-90% UR, por 12 dias. Foram realizadas as análises de pungência e da quantificação de compostos fenólicos totais, antocianinas e de quercetinas, assim como a taxa respiratória, a composição gasosa no interior das embalagens, a coloração, o teor de sólidos solúveis, e de acidez titulável, o pH, os índice de ressecamento e deterioração, a incidência de podridões e as análises microbiológicas. Cebolas armazenadas a temperaturas de 0 e 5°C e cortadas em fatias apresentaram menor pungência, menores variações nos teores de compostos fenólicos, antocianinas e quercetinas, além de menores taxas respiratórias e manutenção dos aspectos físicos e da aparência. A utilização das diferentes embalagens pouco interferiu nos aspectos estudados, exceto no pH, ângulo de cor, concentração gasosa e aparência. Independente dos tratamentos e durante os períodos de armazenamento, houve alteração dos atributos estudados. A cebola minimamente processada teve maior vida útil quando armazenada a 0°C, associada ao corte em fatias. O recipiente de PP reduziu em 3 dias a vida útil da cebola roxa. Os filmes de PP e PEBD proporcionam maior qualidade fisiológica e visual por mais tempo. / The onion (Allium cepa L.) is a plant globally widespread and is important for both production and consumption. In Brazil, it is the third vegetable most produced and it is mainly consumed fresh and as condiment or seasoning. The minimally processed products have been increasing interest in the fresh product market due to the convenience offered to consumers. In the case of onions, the preparation of the bulb is the biggest cause of complaints, since it contains volatile compounds that cause irritation to eyes and gives the handler a characteristic odor in their hands. Its minimal processing may increase their consumption and still reach new markets around the country. To this end, it is necessary to study the physiology and the specific handling for this vegetable. Thus, to understand the changes occurring during the process as well as methods that may minimize such changes. This work aimed to evaluate the biochemical, physiological and microbiological aspects of purple onions minimally processed using different storage temperatures, combined with two cut types, and, subsequently, different packaging, in order to prolong its life. In the first experiment, four storage temperatures was evaluated (0, 5, 10 and 15°C), and two types of cut, being cubes (10 mm edge) and slices (3-5 mm thick). Product was storage during 15 days at selected temperatures and 85-90% RH. In second experiment, the cut that had best performance was used to test different packaging, being polypropylene (PP), polyvinyl chloride film (PVC - 14 ?m), PP film (10 ?m) and low density polyethylene film (LDPE - 10 ?m). The product was stored at 5°C and 85- 90% RH, for 12 days. To evaluate the shelf-life of the product was carried out analyzes of pungency and quantification of phenolic compounds, anthocyanins and quercetins, as well as respiratory rate, gas composition inside the package, the coloring, the soluble solids and titratable acidity content, pH, the rate of drying and deterioration, decay incidence and microbiological analyzes. Fresh-cut onions stored at temperatures between 0 and 5°C and cut into sliced showed low level of pungency, minor variations in the levels of phenolic compounds, anthocyanins and quercetins, and lower respiration rates and maintenance of the physical aspects and appearance. The use of different packaging interfered little in the variables studied, except for pH, hue angle, gaseous concentration and appearance. Regardless of treatments and periods of storage, there was a change of the attributes studied. The fresh-cut onion had longer life when stored at 0°C associated with cut into slices. The container of PP reduced in 3 days life purple onion. The films of PP and LDPE provide higher visual and physiological quality for longer time.

Human norovirus (HuNoVs) are the most common enteric pathogen around the world that cause ~50% of foodborne illness of disease outbreaks annually. HuNoVs are the member of the Caliciviridae family, which consist of small (38 nm), unenveloped, single stranded RNA (ssRNA) viruses. Norovirus are divided into 5 genogroup (GI, GII, GIII, GIV, GV, GVI and GVII). The GI, GII, and GIV cause human illness, in addition, GII.4 genotype cause the most human disease. Due to HuNoVs are difficult cultured in vitro, the cultivable HuNoVs surrogates have been widely studied. Recently, some studies have been conducted with HuNoVs surrogates, for example bacteriophage MS2. MS2 is conservative surrogate for nonenveloped viruses which there is a close relationship to the behavior of HuNoVs, thus we can examine the infection control measures for HuNoVs. Despite plenty of treatment method been done on testing antiviral effect on bacteriophage MS2, for example UV inactivation, steam ultrasound and antimicrobial etc., plant-based nanoemulsion treatment has yet to be explored. Carvacrol is a major component of oregano essential oil and is responsible for their antimicrobial activity on the growth of various microorganism. In this study, carvacrol nanoemulsions were formed by using the spontaneous emulsification for testing the nanoemulsion stability (14 days shelf life study on its droplet size and particle charge) and antimicrobial activity. In carvacrol nanoemulsion 14 days shelf life test, the droplet size and particle charge stay stable at three different treatment environments (4°C, 20°C and 37°C). The results proved that nanoemulsion (was formed with surfactant agents and medium-chain triglycerides) is stable system that gives consistent droplet size and charge. Although, the low antimicrobial activity was investigated at carvacrol nanoemulsion, the strong antimicrobial effects have been found when carvacrol or carvacrol combined with ionic surfactant of treatment on MS2 and Escherichia coli. Taken together, in the wake of growing consumer demand for different “natural” products in a number of industries, our study broadly informs the development and study of functionalized carvacrol active compound that can not only provide beneficial health for human but can also examine antimicrobial efficacy of control measures for public health.

<p>Silver carp (<i>Hypophthalmichthys molitrix</i>)<b> </b>are an underutilized, invasive fish threatening native species throughout major water systems in the United States. The goal of this research was to use silver carp meat to create a value-added product, to analyze the changes in physicochemical structure and consumer liking over time, and to evaluate the benefits of adding soy, pea, and a combination of soy and pea protein isolates to the formulations. Fish nuggets were prepared from minced meat in four treatments consisting of 3% soy protein isolate (SPI), 3% pea protein isolate (PPI), a combination of 1.5% SPI and 1.5% PPI, and a control without plant protein isolate. Nuggets from each treatment were stored frozen for 1.5, 8.5, and 13.5 weeks. Proximate composition, pH, cook loss, textural hardness, expressible moisture, color, microbial counts and lipid oxidation were evaluated. Sensory acceptability was also evaluated for each frozen storage time period and treatment. A descriptive (QDA^™) trained sensory panel was also conducted on all treatments independent of the storage testing. Results showed that lipid oxidation and textural hardness significantly (P < 0.05) increased with frozen storage time. PPI had significantly lower expressible moisture compared to the control at week 1.5, but there were no statistically significant differences between treatments at weeks 8.5 and 13.5. Similarly, formulations with PPI improved (p<0.05) cook loss for week 1.5, but not week 8.5 or 13.5. Overall, sensory acceptability did not change (P > 0.05), with the exception of decreased degree of liking scores for SPI aroma (p=0.03) and flavor (p=0.03)) during the frozen storage period; all degree of liking scores remained above 6.5 throughout analysis, indicating that consumers’ acceptability of the sample treatments over time despite the changes in physicochemical structure. The descriptive panel created an attribute lexicon for the aroma, flavor, and mouthfeel of the fish nuggets and did not find significant differences in intensities for those attributes between the treatments. Although there were measurable changes in oxidation, texture, expressible moisture, and cook loss over 13.5 weeks, these changes did not impact sensory acceptance. The addition of protein isolates improved water holding capacity initially but did not maintain those benefits over extended shelf life and had little impact on consumer liking during any time period. Overall, this study demonstrated that value-added products such as silver carp nuggets can be created using an otherwise under-utilized fish. The fish nuggets had high sensory acceptability, and the addition of protein isolates did not significantly improve their sensory characteristics; therefore, silver carp nuggets can be formulated without the need of additional protein additives .</p>

Purpose: This research will study how hyperspectral sensoring can assess the moisture content of lettuce by monitoring its growth in indoor vertical farming. Research questions: “What accuracy can be achieved when using hyperspectral sensoring for assessing the moisture content of lettuce leaves grown in vertical farming?” “How can vertical farming contribute to sustainability in conjunction with integration of NIR spectroscopy?” Methodology: This study is an experimental study with a deductive approach in which experiments have been performed using the hyperspectral technologies singlespot sensor and the hyperspectral camera Specim FX17 to collect spectral data. To analyze the data from the experiments two regression models were used and trained to make it possible to predict future moisture content values in lettuce. In order to get a better understanding and analyze the results from the experiments, a literature review was also conducted on how hyperspectral imaging has been applied to assess the quality of food products. Conclusion: The achieved accuracies were 58.24 % and 65.54 % for the PLS regression model and the Neural Network model respectively. Employing hyperspectral sensoring as a non-destructive technique to assess the quality of food products grown and harvested in vertical farming systems, contributes to sustainability from several aspects such as reducing food waste, minimizing costs and detecting different quality attributes that affect the food products. / Syfte: Syftet med denna studie är att undersöka hur hyperspektral avbildning kan användas för att bedöma fuktigheten i sallad genom att kontrollera hur den växer i vertikal odling inomhus. Frågeställningar: “Vilken noggrannhet kan uppnås vid användning av hyperspektral avbildning för att bedöma fukthalt hos salladsblad som odlas i vertikal odling?” “Hur kan vertikal odling bidra till hållbarhet i kombination med integration av NIR spectroscopy?”  Metod: Denna studie är en experimentell studie med en kvantitativ metod inom vilken en deduktiv ansats har tillämpats genom användning av de hyperspektrala teknologierna single-spot sensor och hyperspektralkameran Specim FX17 för insamling av spektral data. För att analysera datan från experimenten skapades och tränades två olika regressionsmodeller till att möjliggöra förutsägning av framtida värden av fukthalt i sallad. För att få en bättre förståelse för och kunna göra en bättre analys av resultaten från experimenten, utfördes även en litteraturöversikt på vad tidigare forskning om tillämpningen av hyperspektral avbildning för kvalitetssäkring av matprodukter har visat. Slutsats: Noggrannheten för PLS-regressionsmodellen var 58,24 % och 65,54 % för Neural Network-modellen. Minskat matsvinn och kostnader samt upptäcka olika kvalitetsattribut som påverkar livsmedelsprodukterna är de hållbara resultaten vid bedömning av kvalitet via hyperspektral sensing.

Comparing the protein compositions of three fishes, grass carp exhibited lower band intensity at 47.9 KDa, β-tropomyosin (36.5 KDa), and missed the band at 15.9 KDa myosin light chain. Bigmouth buffalo had a darker tropomodulin (38.8 KDa) band and smaller α-tropomyosin (33-37 KDa) than silver and grass carp. The breaking force (611.8 g) and deformation (11.7 mm) of silver carp cooked gel were significantly higher than the other two fish products. The addition of starches at 2, 4, and 6% to the grass carp paste lowered the breaking force of the cooked gel in a dose-responsive manner compared to the control (P<0.05), but no differences were found in bigmouth buffalo. The bioumulated Murine Norovirus-1 (MNV-1) was found to maintain infectivity during storage of live oysters at 5°C for 15 days while the inoculated MNV-1 kept infectious for 20 days in cooked surimi and salmon fillet. Treatments with 4.0 kGy X-ray achieved the reductions of 3.7 log PFU mL-1 in pure culture or 2.7, 2.2, and 2.0 log PFU g-1 in half-shell oyster, salmon sushi and tuna salad, respectively. X-ray significantly reduced the population of internalized MNV-1 in live oysters from 4.3 ± 0.4 log PFU g-1 to 3.6 ± 0.5, 3.2 ± 0.2, 2.8 ± 0.2, and 2.5 ± 0.1 log PFU g-1, by 1.0, 2.0, 3.0, and 4.0 kGy X-ray, respectively. The population of MNV-1 was reduced to less than 2.0 log PFU g-1 at 5.0 kGy X-ray. The survivability of live oysters was not significantly affected by treatment with 5.0 kGy X-ray, in comparison with the control, for up to 10 days, respectively, during storage at 5°C. Fish sauce was fermented from the by-products of silver carp. The total nitrogen content of fish sauce made in April, and November were 9.86±0.9 and 9.71±4.5 g/l, respectively, which was significantly (p<0.05) higher than the sample of February (8.45±0.25 g/l ), reflecting seasonal effect. The total nitrogen, amino acid nitrogen, pH, and sodium chloride of fish sauce made from silver carp by-products met the international fish sauce standard code of CODEX STAN 302-2011.

The Norwegian Food Research Institute (Nofima) and the University of Borås worked together to develop this project. The commonly used packaging materials pose a serious threat to the environment, as they are produced from nonrenewable crude oil and cannot decompose naturally. Despite some manufacturers' claims of their products being eco-friendly or sustainable, they are not entirely made from renewable resources and are not biodegradable. Nevertheless, some bio-based materials have emerged as a viable alternative that can naturally break down and safely decompose in the environment. Despite many studies, biopolymers possess limited mechanical and barrier properties, which restricts their potential for use in products. To overcome this limitation, polymer blending can be employed to enhance their final properties and make them more suitable for various applications. The objective of this project was to design sustainable food packaging using biopolymers. PHBV, one of the PHA’s bio-based polymers, was blended with other polymers to enhance its properties as a sustainable food packaging material. Through blending, PHAs'physical, chemical, and thermal properties can be enhanced to obtain exceptional films for food packaging purposes. Finally, in this work, a bio-based polymer, polyhydroxyalkanoate, was used to producea biodegradable packaging system for potential food packaging applications. The effect of the physical modification of PHBV on mechanical and barrier properties was studied by blending it with biodegradable polymers such as PLA and PBAT. Thermal properties were analyzed using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and FourierIItransform infrared spectroscopy (FTIR) while the mechanical properties were evaluated by tensile test. Barrier properties were characterized using water vapor transmission rate (WVTR). The mechanical performance of PHBV 50%: PBAT 50% blend has been significantly improved, leading to better tensile properties. The high crystallinity of the PHBV 50%: PBAT 50% blend than other blends have been found to enhance the barrier properties of the polymer film, according to DSC analysis. FTIR investigations have suggested no difference in absorption peaks between the blends and the neat material. Furthermore, WVTR investigations have shown that PHBV50%: PBAT50% exhibits excellent barrier properties against water vapor, making it a highly promising material.

This study investigated the antimicrobial efficacy of bioactive plant compounds along with high pressure processing (HPP) against pathogens Bacillus cereus and Cronobacter sakazakii in infant formula and infant rice cereal. The influence of these applications on antimicrobial activity, shelf-life and sensory attributes of infant foods were examined. Trans-cinnamaldehyde (TC), (-)-Epigallocatechin gallate (EGCG) and [10]-Gingerol (GI) were incorporated (0.05%) in infant rice cereal reconstituted with infant formula. The cereal was inoculated with either B. cereus (ATCC 14579) or B. cereus spores (107-108 log CFU g-1). All the samples were stored at 7, 23 or 37°C for 0, 4, 8 and 24 h. TC showed the highest antimicrobial activity by inhibiting the B. cereus and its spores up to 2.72 and 3.8 log CFU g-1, respectively. HPP (600 MPa for 5 m), and TC (0.05-0.1%) along with Chitosan (CH) (1%), were applied to reconstituted powder infant formula which was inoculated with either 3 strains of C. sakazakii (ATCC 29544, ATCC 12868, and ATCC BAA 894) or 5 strains of B. cereus spore (ATCC 14579, ATCC 33018, ATCC 12826, ATCC 4342, and Difco Spores) cocktail (107-108 log CFU ml-1). All the samples were stored at 7, 23 or 45°C for 5-8 weeks. HPP and TC (0.1%) combination exhibited the highest inhibition (P < 0.05) by reducing the B. cereus spores 2.97 log CFU ml-1 after 7 d. C. sakazakii was fully inactivated by HPP, TC (0.05%) and C (1%) combination following 8 weeks of storage at 7 and 23°C and 2 weeks storage at 45°C. The combination of HPP and bioactive compounds exhibited additive antimicrobial effect. Gradual decrease (P < 0.05) in pH was observed in rice cereal and non-HPP formula samples due to the microbial growth and metabolic activity. Significant differences (P < 0.05) were found in color, aroma and general appearance of EGCG and GI applied cereal samples, while TC only did exhibit a cinnamon taste. In summary, the antimicrobial findings suggest that TC, EGCG, GI and CH could be incorporated in infant foods along with HPP as natural and safe alternatives to synthetic preservatives and thermal applications.