Made available in DSpace on 2015-03-26T13:39:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 518774 bytes, checksum: 06773571b81e5a7f0d521a081f2219a8 (MD5) Previous issue date: 2006-07-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this work was to determine the most efficient potassium permanganate (KMnO4) dose associated with plastic packaging in delaying processes related to ripening of 'Sunrise Golden' papaya stored under refrigeration and room temperature. Fruits were wrapped in low-density polyethylene bags with KMnO4 sachets. Two experiments were conducted: Experiment 1: storage at 10.42 ± 0.96 C and 90 ± 5% RH, and KMnO4 doses of 0; 0.5; 1; 1.5; and 2 g/bag; and Experiment 2: storage at 20.05 ± 0.50 C and 90 ± 5% RH and KMnO4 doses of 0; 1; 2; 3; and 4 g/bag. In the Experiment 1, three fruits with average weight of 289±18.49 g each were maintained in the bags for 25 days, while in the Experiment 2, three fruits with average weight of 278±18.86 g each were kept for 15 days at the temperatures previously mentioned. After these periods, the fruits were removed from the bags. Fruits from Experiment 1 were kept at 21.02 ± 0.80 C and 90 ± 5% RH, while fruits from Experiment 2 were kept in the same environment. The experiments were arranged in split plots, with KMnO4 doses in the plots, and in the subplots, the days of evaluation after the removal from packaging, with 0, 1, 2, 3, 5 and 6 days in experiment 1 and 0, 1, 2, 3, 4 and 5 days in experiment 2, in a randomized complete block design with three repetitions and three fruits per experimental unit. For the analyses of CO2 concentration within the bags, experiments with the five KMnO4 doses and five repetitions, with three fruits per experimental unit, were set up in parallel. After 25 days of storage at 10.42 ± 0.96 C, the fruits without KMnO4 were not significantly different from the treated fruits for the characteristics peel color index, consistency of pulp and electrolyte, indicating that refrigeration associated with plastic film was efficient in inhibiting alterations in these characteristics. However, after removing the fruits from conditions of refrigerated storage and modified atmosphere, it was observed the effect of KMnO4 on delaying alterations in pulp firmness, peel color, solute leakage and soluble solids concentration compared to KMnO4 non-treated fruits. After 15 days of storage at 20.05 ± 0.50 C, fruits without KMnO4 had higher CO2 production, more intense peel color, higher cell electrolyte leakage and lower firmness when compared to KMnO4-treated fruits, indicating that non-treated fruits had premature ripening. After removing the packaging, the KMnO4-treated fruits maintained firmness for two days, reaching values similar to the non-treaded ones only on the fifth day of evaluation. / O objetivo deste trabalho foi determinar a dose de permanganato de potássio (KMnO4) associado à embalagem plástica, mais eficiente em retardar os processos relacionados ao amadurecimento do mamão Sunrise Golden armazenado sob refrigeração e à temperatura ambiente. Os frutos foram embalados em filmes de polietileno de baixa densidade, nos quais foram incluídos sachês KMnO4. Foram conduzidos dois experimentos: experimento 1: armazenamento a 10,42 ± 0,96 °C e 90 ± 5% de UR e doses de KMnO4 de 0,0; 0,5; 1,0; 1,5; e 2,0 g/embalagem; e experimento 2: armazenamento a 20,05 ± 0,50 °C e 90 ± 5% de UR e doses de KMnO4 de 0,0; 1,0; 2,0; 3,0; e 4,0 g/embalagem. No experimento 1, três com massa média de 289±18,49 g cada foram mantidos nas embalagens durante 25 dias, enquanto no experimento 2 foram acondicionados três com massa média de 278±18,86 g cada, durante 15 dias, nas temperaturas mencionadas anteriormente. Após esses períodos, os frutos foram retirados das embalagens. Já os do experimento 1 foram mantidos a 21,02 ± 0,80 °C e 90 ± 5% de UR, enquanto os do experimento 2 permaneceram no mesmo ambiente. Os experimentos foram montados em parcelas subdividas, tendo nas parcelas as doses de KMnO4 e, nas subparcelas, os dias de avaliação após a remoção das embalagens, sendo 0, 1, 2, 3, 5 e 6 dias no experimento 1 e 0, 1, 2, 3, 4 e 5 dias no experimento 2, no delineamento inteiramente casualizado com três repetições e três frutos por unidade experimental. Para as análises de concentração de CO2 no interior das embalagens foram montados experimentos à parte com as cinco doses de KMnO4 e cinco repetições, sendo três frutos por unidade experimental. Após 25 dias de armazenamento a 10,42 ± 0,96 °C, os frutos sem KMnO4 não apresentaram diferenças significativas quando comparados com os frutos tratados para as características índice de cor da casca, consistência da polpa e extravasamento de eletrólitos, indicando que a refrigeração associada ao filme plástico foi eficiente em inibir alterações nessas características. No entanto, após a retirada dos frutos das condições de armazenamento refrigerado e atmosfera modificada observou-se o efeito do KMnO4 em retardar alterações na firmeza da polpa, na coloração da casca, no extravasamento de solutos e no teor de sólidos solúveis, em comparação com os frutos não-tratados com KMnO4. Após 15 dias de armazenamento a 20,05 ± 0,50 °C, os frutos sem KMnO4 apresentavam maior produção de CO2, coloração da casca mais avançada, maior perda de eletrólitos celulares e menor firmeza quando comparados com frutos tratados com KMnO4, indicando que os não-tratados tiveram amadurecimento antecipado. Após a retirada das embalagens, os frutos tratados com KMnO4 permaneceram firmes durante dois dias, alcançando valores de firmeza semelhantes aos dos não-tratados somente no quinto dia de avaliação.

Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-16T19:41:21Z No. of bitstreams: 1 WÉLIDA CRISTINA DANTAS VENCELAU - DISSERTAÇÃO PPGSA PROFISSIONAL 2013..pdf: 1365173 bytes, checksum: 20576f26089aa96ddf1d6ad5fb8dcaa5 (MD5) / Made available in DSpace on 2018-05-16T19:41:21Z (GMT). No. of bitstreams: 1 WÉLIDA CRISTINA DANTAS VENCELAU - DISSERTAÇÃO PPGSA PROFISSIONAL 2013..pdf: 1365173 bytes, checksum: 20576f26089aa96ddf1d6ad5fb8dcaa5 (MD5) Previous issue date: 2013 / A goiaba destaca-se por possuir excelente qualidade nutricional e funcional. No entanto, devido à intensa atividade metabólica desse fruto os cuidados pós-colheita são essenciais para a redução das perdas e manutenção de sua qualidade. Neste contexto, as técnicas de conservação visam reduzir as taxas metabólicas, mantendo os frutos na fase pré-climatérica por um período mais longo. Este trabalho teve como objetivo avaliar a qualidade e a capacidade antioxidante de goiabas „Paluma‟, submetidas à atmosfera modificada utilizando biofilme comestível a base de fécula de mandioca, polietileno a vácuo e controle (sem revestimento), armazenadas sob duas temperaturas (24 °C e 10 °C). O presente estudo foi subdividido em três experimentos, onde: Experimento I - foram avaliadas as características físicas, químicas, compostos bioativos e capacidade antioxidante da goiaba „Paluma‟ em diferentes estádios de maturação; Experimento II - foram comparados os efeitos em goiabas ‟Paluma‟ revestidas com biofilme de fécula de mandioca a 2% e 4% (BFM 2 e 4%), polietileno a vácuo e controle (sem revestimento) no comportamento pós-colheita dos frutos armazenados sob temperatura de 24 °C por um período de 10 dias e temperatura refrigerada de 10 °C por um período de 24 dias; e Experimento III - foram identificados os compostos bioativos e capacidade antioxidante dos dois melhores tratamentos avaliados no Experimento II (tratamentos com BFM a 2% e polietileno a vácuo armazenados a 10 °C). Os experimentos foram realizados no Laboratório de Tecnologia de Produtos de Origem Vegetal do CCTA/UFCG, no Campus de Pombal - PB. Para os três experimentos o delineamento utilizado foi inteiramente casualizado. Em relação ao Experimento I, o efeito dos tratamentos foi avaliado através da análise de variância e a comparação das médias foi feita pelo teste de Tukey ao nível de 5% de probabilidade. Para o Experimento II o delineamento foi disposto em esquema fatorial 4 x 6 (4 tratamentos com atmosfera modificada e 6 períodos de avaliações) para temperatura de 24 °C e 4 x 7 (4 tratamentos com atmosfera modificada e 7 períodos de avaliações) para temperatura de 10 °C, com três repetições de dois frutos/parcela. As temperaturas foram avaliadas independentes dos tratamentos aplicados. A partir dos resultados das análises de variância preliminares, os resultados foram submetidos à análise de regressão polinomial. Em relação ao Experimento III foi disposto em um esquema fatorial 2 x 7 (2 os tratamentos co atmosfera modificada e 7 os períodos de avaliação), com três repetições de dois frutos/parcela. A partir dos resultados das análises de variância preliminares, os resultados foram submetidos à análise de regressão polinomial. Verificou-se que o estádio IV (pigmentação verde predominante com traços amarelos) reuniu as melhores características, físicas e químicas para conservação pós-colheita, entretanto o estádio III (indício da pigmentação amarela) foi indicado o melhor para comercialização, principalmente visando mercados mais distantes. A goiaba ´Paluma` apresentou teores satisfatórios para ácido ascórbico, carotenoides e compostos fenólicos, constituindo fontes potenciais de compostos bioativos naturais e de excelente capacidade antioxidante. As atmosferas modificadas (polietileno a vácuo e biofilme de fécula de mandioca a 2%) associadas à refrigeração (10 °C) conservaram a qualidade e a integridade dos frutos, mantendo-os túrgidos, aparência atrativa durante um período mais prolongado. Goiabas „Paluma‟ podem ser classificadas frutos com elevado poder antioxidante, principalmente na casca, devendo, portanto, estimular o consumo desta fruta na íntegra. A polpa de goiabas „Paluma‟ revestidas com biofilme de fécula de mandioca a 2% e sob refrigeração apresentou maior ação antioxidante. / The guava stands out by having excelent nutrional and functional quality. However, due to the intense metabolic activity oh this fruit, postharvest care are essential to reducing losses and conservation its quality. In this context, preservation techniques intended to reduce the metabolic rates, kuping the fruit in preclimateric stage for a intended period. The aim of this work was to evaluate the quality and antioxidant capacity of „Paluma‟ guavas, when submitted to modified atmosphere using edible biofilm based for manioc starch, vacuum polyethylene and control (without coating), it was stored at two temperatures (24 °C and 10 °C). The present study was divided in three experiments, where: Experiment I – were evaluated physical, chemical, bioactive compounds and antioxidant capacity of guava „Paluma‟ at different stages of maturation; Experiment II – the effects were compared in guava „Paluma‟ coated for manioc starch 2% and 4% (BFM 2% e 4%), vacuum polyethylene and control (without coating) in the postharvest fruit store at 24 °C for a period of 10 days and refrigerated temperature of 10 °C for a period of 24 days; Experiment III – were indentified the bioactive compounds and antioxidant capacity of the two best treatments evaluated in the Experiment II (treatments with BFM 2% and vacuum polyethylene stored at 10 °C). The experiments were performed at the Laboratory Technology Products of Plant Origin of UFCG/CCTA/UATA, Campus Pombal – PB. For three experiments, was carried out in complete randomized design. In relation to the first experiment, the effect of the treatments was evaluated through of analysis of variance and comparison of average was done by Tukey test at 5 % probability. For the second experiment, the design was established in a factorial 4 x 6 (4 treatments and modified atmosphere periods of 6 reviews) to 24 °C and 4 x 7 (4 treatments modified atmosphere and periods of 7 reviews) to 10 °C, with three replicates of two fruits/portion. Temperatures were evaluated independent of the applied treatments. From the results of preliminary analyzes of variance, the results were subjected to polynomial regression. Compared to Experiment III was established in a factorial 2 x 7 (first factor corresponds to the two treatments and the second factor corresponds to the evaluation periods), with three replicates of two fruits/portion. From the results of preliminary analyzes of variance, the results were subjected to polynomial regression. The stage IV (predominantly green with yellow pigmentation traits) gathered the best characteristics physical and chemical for postharvest conservation, however stage III (early yellow pigmentation) was recommended for the best the marketing, mainly, targeting distant markets. The guava 'Paluma' showed satisfactory levels for ascorbic acid, carotenoids and phenolic compounds, being potential sources of bioactive compounds for human diet and excellent antioxidant capacity. Modified atmospheres (vacuum and polyethylene biofilm manioc starch 2%) associated with refrigerated temperature preserved the quality and integrity of the fruit, keeping them turgid, attractive appearance for a longer period. 'Paluma' guava has powerful high antioxidant and can be classified, mainly, on the peel and therefore, the consuming fruit should be made in its totality. The pulp of 'Paluma' coated edible biofilm of manioc starch 2% and under refrigeration showed higher antioxidant activity.

Atualmente, existem inúmeros questionamentos quanto aos prováveis efeitos mutagênicos e carcinogênicos dos antioxidantes sintéticos no organismo, e devido a isto, hoje em dia estudos tendem a promover a substituição destes compostos por naturais com o intuito de maior segurança do alimento, sendo que estes apresentam benefícios potenciais à saúde. O objetivo deste estudo foi o uso de antioxidantes naturais obtidos de ervas e especiarias no desenvolvimento de produtos cárneos a base de carne ovina buscando suas propriedades antioxidantes e sensoriais, bem como agregar valor ao produto final, desenvolvido com carne de baixo valor comercial. O apelo de saudabilidade dos produtos foi obtido pela adição de extratos antioxidantes naturais à base de ervas aromáticas selecionadas em função de seu poder antioxidante e harmonização de sabores com a carne ovina. Um primeiro experimento (Capítulo 2) consistiu na avaliação da capacidade antioxidante dos extratos de 13 espécies vegetais, sendo selecionados por Cluster analysis em relação a três métodos colorimétricos e sensorialmente após a adição em produto cárneo. O extrato selecionado foi avaliado quanto a acidez, à identificação e quantificação de compostos fenólicos e utilizado para a elaboração de hambúrguer congelado (Capítulo 3) e linguiça cozida (Capítulo 4), em diferentes concentrações, além de hambúrguer refrigerado sob atmosfera modificada (80% O2 + 20% CO2) (Capítulo 5), sendo comparados com tratamentos sem antioxidante (controle) e contendo antioxidante sintético (eritorbato de sódio ou BHT). Estes produtos cárneos foram avaliados durante armazenamento, respectivamente de 120, 135 e 20 dias, a partir de análises físico-químicas, sensoriais e microbiológicas, sendo inicialmente caracterizados quanto à composição centesimal. Orégano, manjerona, melissa e alecrim foram os extratos selecionados após agrupamento por similaridade quanto à capacidade antioxidante, sendo que os hambúrgueres elaborados com estes quatro extratos naturais não comprometeram a aceitação sensorial em relação ao eritorbato de sódio (P>0,05). Resumidamente, os produtos cárneos elaborados mostraram resultados relevantes quanto à estabilidade oxidativa, apresentando os tratamentos contendo extrato natural, efeitos antioxidantes melhores e/ou compatíveis aos antioxidantes sintéticos. Hambúrguer congelado apresentou mais de 50% de redução (P<0,001) para nível de substâncias reativas ao ácido tiobarbitúrico (TBARS), enquanto que linguiças cozidas apresentaram os menores valores para compostos voláteis (P<0,001) aos 135 dias de estocagem e a presença do extrato em hambúrgueres sob atmosfera modificada (ATM) manteve a qualidade sensorial por até 15 dias de armazenamento. Apesar de diferentes sistemas testados, o ensaio de redução férrica (FRAP) foi o método em comum mais eficaz para estimar a quantidade adequada de antioxidante natural a ser adicionada em comparação ao eritorbato de sódio. Em conclusão, extrato de orégano adicionado em produtos a base de carne ovina apresentou efeitos antioxidantes equivalentes aos antioxidantes sintéticos, não comprometendo a maioria dos parâmetros físico-químicos, microbiológicos e sensoriais, sendo considerado uma alternativa viável e favorecida pela grande vantagem da saudabilidade. / Currently, there are many questions concerning probable mutagenic and carcinogenic effects of synthetic antioxidants in the organism, and because of this, nowadays studies tend to promote the substitution of these by natural compounds with the aim of greater food safety and potential benefits for the health. The objective of this study was the use of natural antioxidants obtained from herbs and spices in the development of meat products ovine meat looking theirs antioxidant and sensory properties as well as add value to the final product, which was developed with low commercial value meat. The healthiness appeal of the product was obtained by adding natural antioxidants based extracts of aromatic herbs to be selected according to its antioxidant power and harmonization of flavors with the sheep meat. A first experiment (Chapter 2) was performed to evaluate the antioxidant capacity of 13 plant species extracts, being selected by Cluster analysis in relation to three colorimetric methods and sensory, after the addition in meat product. The selected extract was evaluated for acidity, identification and quantification of phenolic compounds and used for the preparation of frozen hamburger (Chapter 3) and cooked sausage (Chapter 4), at different concentrations, and refrigerated hamburger under modified atmosphere (80% O2 + 20% CO2) (Chapter 5), being compared to treatments without antioxidant (control) and containing synthetic antioxidant (sodium erythorbate or BHT). These meat products were evaluated during storage, respectively of 120, 135 and 20 days, from physical-chemical, sensory and microbiological analyzes, being initially characterized for chemical composition. Oregano, marjoram, lemon balm and rosemary were the extracts selected after grouping by similarity of the antioxidant capacity, and the hamburgers made with these four natural extracts did not affect the sensory acceptance in comparison to sodium erythorbate (P>0.05). Briefly, the meat products showed significant results in terms of oxidative stability, being the treatments containing natural extract presented best effects antioxidant and/or compatible to synthetic compounds. Frozen burger presented more than 50% reduction (P<0.001) for tiobarbituric acid reactive substance TBARS, while cooked sausages had the lowest values for volatile compounds (P<0.001) at 135 days of storage, and the extract presence in burgers under modified atmosphere kept the quality sensory up to 15 days. Although different systems tested, ferric reducing antioxidant power (FRAP) was more effective common method to estimate the appropriate amount of natural antioxidant to be used in comparison to sodium erythorbate. In conclusion, oregano extract added products in the sheep meat presented equivalent antioxidant effects without to compromise the majority of physical-chemical, microbiological and sensory parameters, being thus considered a viable alternative, favored by the great advantage of healthiness.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este trabalho teve por objetivos verificar atravÃs da caracterizaÃÃo de frutos do bacurizeiro da RegiÃo do Meio Norte, quais as melhores condiÃÃes de atmosfera, de tempos e temperaturas de armazenamento, para prolongar a vida pÃs - colheita do bacuri (Platonia insignis Mart) para comercializaÃÃo in natura. Os frutos colhidos na planta, armazenados sob atmosfera modificada apresentaram Ãtima aparÃncia externa e interna atà o final do experimento (25 dias), enquanto que os armazenados sob atmosfera ambiente tiveram sua aparÃncia externa comprometida apÃs o sexto dia, entretanto sua aparÃncia interna foi satisfatÃria atà o final do experimento. A perda de massa foi maior nos frutos sem filme, com perdas de atà 47% aos 25 dias de armazenamento, contra 8% nos frutos com filme. A qualidade fÃsico-quimica da polpa foi pouco afetada durante o armazenamento com destaque para os sÃlidos solÃveis totais que apresentaram menor percentual nos frutos com filme. Os frutos colhidos na planta, armazenados a 7 ÂC em atmosfera modificada tiveram sua aparÃncia externa comprometida apÃs 20 dias, por injÃrias pelo frio, enquanto que nas temperaturas de 9 e 11 ÂC a vida Ãtil foi de 36 dias. A coloraÃÃo das frutas evoluiu de verde claro para amarelo apenas nas temperaturas de 9 e 11 ÂC, sendo que a 11 ÂC a coloraÃÃo atingiu uma maior intensidade. A qualidade da polpa praticamente nÃo foi afetada pelas temperaturas de armazenamento. Os frutos apanhados apÃs caÃrem da planta, armazenados a temperatura ambiente e atmosfera modificada tiveram sua aparÃncia externa comprometida no dÃcimo nono dia de armazenamento e a interna apÃs 21 dias. Jà para os frutos armazenados sob refrigeraÃÃo e atmosfera modificada, a aparÃncia externa foi comprometida aos 28 dias de armazenamento, apesar de apresentar aparÃncia interna satisfatÃria atà o trigÃsimo quinto dia. A perda de massa foi de 7,74% e 2,17%, nos frutos armazenados a 25 ÂC e 12 ÂC, respectivamente. Os frutos armazenamento a temperatura ambiente tiveram rendimento em torno de 16%, enquanto, que os frutos armazenados sob refrigeraÃÃo o rendimento foi de 15%. Os valores dos SST decresceram durante o armazenamento nas duas temperaturas avaliadas. ApÃs 35 dias de armazenamento a 25 ÂC os frutos apresentaram em mÃdia 12,12 ÂBrix, enquanto que a 12 ÂC apÃs 42 dias de armazenamento apresentaram um valor de 11,28 ÂBrix. Os valores de pH apresentaram pouca variaÃÃo atravÃs do tempo nas duas condiÃÃes de armazenamento e a AT obteve maior variaÃÃo no armazenamento a 25 ÂC. A relaÃÃo SST/AT apresentou variaÃÃes considerÃveis entre o inicio e o final nos dois tipos de armazenamento, sendo mais intenso no armazenamento a temperatura ambiente. Os frutos apresentaram baixos teores de compostos fenÃlicos em todas as fraÃÃes caracterizando a polpa de bacuri como pouco adstringente, demonstrando potencial para consumo in natura, alÃm de pouco teor de vitamina C, nas duas condiÃÃes de armazenamento. / This work had for objectives to verify through the characterization of fruits of the bacuri tree of the Area of the North Middle, which the best atmosphere conditions, of times and storage temperatures, to prolong the life post-harvest of the bacuri (Platonia insignis Mart) for commercialization in natura. The fruits picked in the plant, stored under modified atmosphere they presented great appearance it expresses and it interns until the end of the experiment (25 days), while stored them under atmosphere it adapts they had your appearance it expresses committed after the sixth day, however your internal appearance was satisfactory until the end of experiment. A mass loss it was larger in the fruits without film, with losses of up to 47% to the 25 days of storage, against 8% in the fruits with film. The physical-chemical quality of the pulp was little affected during the storage with prominence for the total soluble solids that presented smaller percentile in the fruits with film. The fruits picked in the plant, stored 7 ÂC in modified atmosphere they had your appearance it expresses committed after 20 days, for offenses for the cold, while in the temperatures of 9 and 11 ÂC useful life was of 36 days. The coloration of the fruits just developed of clear green for yellow in the temperatures of 9 and 11 ÂC, and to 11 ÂC the coloration reached a larger intensity. The quality of the pulp practically was not affected by the storage temperatures. The fruits been hit after you/they fall of the plant, stored the temperature it adapts and modified atmosphere had your appearance it expresses committed in the nineteenth day of storage and the intern after 21 days, already for the fruits stored under refrigeration and modified atmosphere, the appearance expresses it was committed to the 28 days of storage, in spite of presenting satisfactory internal appearance until the thirtieth fifth day. The mass loss was of 7.74% and 2.17%, in the fruits stored 25 ÂC and 12 ÂC, respectively. The fruits storage the temperature adapts they had revenue around 16%, while, that the fruits stored under refrigeration the revenue it was of 15%. The values of SST decreased during the storage in the two appraised temperatures. After 35 days of storage to 25 ÂC the fruits presented 12.12 ÂBrix on average, while to 12 ÂC after 42 days of storage presented a value of 11.28 ÂBrix. The values of the pH presented little variation through the time in the two storage conditions and the AT obtained larger variation in the storage to 25 ÂC. The relationship SST/AT presented considerable variations among I begin him/it and the end in the two storage types, being more intense in the storage the temperature adapts. The fruits presented low tenors of phenolic compounds in all the fractions characterizing the bacuri pulp as little astringent, demonstrating potential so much for consumption in natura, besides little vitamin tenor C, in the two storage conditions.

Pork rib is a minimally processed product since it is a kind of meat that has only been cut and immediately packed and refrigerated. It has a short shelf-life, which is determined mainly for the microbiological deterioration. Having the objective of verifying the efficiency (antimicrobiotic and antioxidant action) of preservation methods applied associated to the shelf-life of pork ribs, the latter were bathed in the following solutions: Minerat B® solution (market product) in 10% = T1, organic acid mixed solution (1% lactic acid, 1% citric acid, 1% acetic acid and 0,8% ascorbic acid) = T2, lactic acid solution in 1,25% = T3, acid solution of sodium cloret (0,6% of citric acidand 0,1% of NaCl) = T4. One of the samples had no bathed solution and it was considered as controll = C. Afterwards, the samples were stored in packages that contained modified atmosphere (CO2 69,93% + N2 29,57% + CO 0,5%) in these proportions: 2:1 (gas:meat), in the first test and 3:1 in the second one, and stored under 5°C (± 1°C), considering that in the first test the samples remained, inicially, under 1°C (± 1°C) for one week. Mesophile aerobic microorganisms, psychrotrophy and lactic bacteria counting, pH and TBA index determination and sensorial anlysis were made. In the first test, the T2 treatment obtained a better performance while reducing the microbiological growth and also greater durability (between 21 and 24 days) but in the second test, the greatest antimicrobiotic effect was achieved by T3, however, T4 had greater durability (19 days). In terms of TBA index, all results were below the minimum limit for the showing of undesirable characteristics. Sensorially, in the first test, among the raw samples, T4 had greater acceptability, and among the roasted it was T3. In the second test, among the raw samples, T2 obtained the best color and T4 had the best odor, and among the roasted it was T2. The samples acquired a bright cherry red color that remained throughout and after the end of the analyses, not showing indication of deterioration, even after its occurence. According to the results, one can say that the treatments that were used (modified atmosphere + antimicrobiotic bath) have shown to be efficient in the preservation of refrigerated pork ribs, even under different degrees, and do not interfeer negatively in their sensorial characteristics. / A costela suína é um produto "minimamente processado" por se tratar de uma carne que sofreu apenas cortes e em seguida foi embalada e refrigerada, possuindo um curto shelf-life, que é determinado principalmente pela deterioração microbiológica. Com o objetivo de verificar a eficiência (ação antimicrobiana e antioxidante) de métodos de conservação, aplicados associados, sobre a vida de prateleira de costelas suínas, as mesmas foram aspergidas com as seguintes soluções: solução de Minerat B® (produto comercial) a 10% = T1, solução de mistura de ácidos orgânicos (1% de ácido lático, 1% de ácido cítrico, 1% de ácido acético e 0,8% de ácido ascórbico) = T2, solução de ácido lático a 1,25% = T3, solução ácida de cloreto de sódio (0,6% de ácido cítrico e 0,1% de NaCl) = T4. Uma das amostras não teve nenhuma solução aspergida, sendo considerada como controle = C. Após, as amostras foram armazenadas em embalagens contendo atmosfera modificada (CO2 69,93% + N2 29,57% + CO 0,5%) nas proporções: 2:1 (gás:carne),no primeiro ensaio e 3:1 no segundo ensaio, e armazenadas a 5°C (± 1°C), sendo que no primeiro ensaio as amostras permaneceram, inicialmente, a 1°C (± 1°C) por uma semana. Contagens de microrganismos aeróbios mesófilos, psirotróficos e bactérias láticas, determinação do pH e do índice de TBA e análise sensorial foram realizadas. No primeiro ensaio, o tratamento T2 obteve um melhor desempenho em reduzir o crescimento microbiológico e também a maior durabilidade (entre 21 e 24 dias), porém, no segundo ensaio, o maior efeito antimicrobiano foi alcançado por T3, no entanto T4 teve maior durabilidade (19 dias). Em relação ao índice de TBA, todos os valores encontrados ficaram abaixo do limite mínimo para o aparecimento de características indesejáveis. Sensorialmente, no primeiro ensaio, dentre as amostras cruas T4 teve maior aceitabilidade, e dentre as assadas foi T3. No segundo ensaio, dentre as amostras cruas T2 obteve a melhor coloração e T4 o melhor odor e dentre as assadas foi T2. As amostras adquiriram uma coloração vermelho cereja brilhante que permaneceu durante e após o término das análises, não havendo indicação de deterioração, mesmo após sua ocorrência. De acordo com os resultados obtidos, pode-se dizer que os tratamentos utilizados (atmosfera modificada + aspersão com antimicrobianos) demonstraram ser eficientes na conservação de costelas suínas refrigeradas, mesmo em diferentes graus, e não interferir negativamente nas características sensoriais das mesmas.

Doctor of Philosophy / Department of Animal Sciences and Industry / Michael E. Dikeman / The objectives were to determine the effects of packaging and injection-enhancement on beef sensory attributes, postmortem proteolysis, and color. Muscles from USDA Select, A-maturity carcasses were fabricated into 2.54-cm steaks on d 7 postmortem. In Experiment 1, longissimus lumborum (n=14 pairs) muscles were used. Packaging treatments were: vacuum packaging (VP); 80% O2/20% CO2 (HiO2); 0.4% CO/35% CO2/64.6%N2 (ULO2CO); 0.4% CO/99.6% CO2; 0.4% CO/99.6% N2; or 0.4% CO/99.6% Ar. In Experiment 2, longissimus lumborum (n=12 pairs); semitendinosus (n=12 pairs); and triceps brachii (n=24 pairs) muscles from one carcass side were injection-enhanced or non-enhanced. Steaks were packaged into VP, HiO2, or ULO2CO MAP. Steaks packaged in HiO2 MAP were in dark storage (2°C) for 4 d and all other steaks for 14 d. Steaks were displayed under fluorescent lighting for 7 d. Trained color panelists assigned color scores. Steaks for tenderness, cooked color, and sensory were cooked to 70°C. Steaks packaged in VP or ULO2 with CO MAP had little or no discoloration. Steaks packaged in HiO2 MAP discolored faster (P < 0.05) and more (P < 0.05) than steaks in other packaging treatments. Steaks packaged in HiO2 MAP were less tender (P < 0.05) than other treatments at the end of display, but had 10 d less aging due to shorter dark storage. Steaks packaged in HiO2 had the lowest (P < 0.05) a* values for internal cooked color of all treatments and exhibited premature browning. Enhanced steaks were more tender (P < 0.05) than non-enhanced steaks. Sensory panelists found that non-enhanced steaks packaged in ULO2CO MAP or VP were more tender (P < 0.05), had more (P < 0.05) beef flavor, and had less (P < 0.05) off-flavors than steaks packaged in HiO2 MAP. Off-flavors for steaks packaged in HiO2 MAP often were described as oxidative and rancid. Enhanced steaks had more (P < 0.05) off-flavors than non-enhanced steaks. Postmortem proteolysis measured by desmin degradation was not affected (P > 0.05) by packaging. Steaks packaged in ULO2 plus CO MAP had superior color stability, tenderness, and sensory attributes compared to steaks in HiO2 MAP.

The effects of natamycin, oxygen scavengers and a 25% CO₂:75% N₂ modified atmosphere on the growth of <I>Penicillium roqueforti</I> in shredded cheddar and mozzarella cheese stored at 10°C for 0, 60, 120, or 180 day was studied. Microbiological and sensory testing was assessed on 0, 7, 14 and 21 days after opening. Carbon dioxide decreased (P<0.05) as O₂ (P>0.05) and N₂ (P>0.05) increased throughout storage. Cheddar and mozzarella cheeses were stored for 180 and 60 days, respectively without significant (P> 0.05) increases in yeast and mold populations. Fungal populations increased significantly (P< 0.05) after packages were opened. Differences in yeast and mold (YM) counts during storage and once the packages were opened were independent of natamycin application and presence, O₂ scavengers and inoculated <I>Penicillium roqueforti</I> for both types of cheeses. Growth of <I>Penicillium roqueforti, Aspergillus niger, Geotrichum candidum</I> and <I>Neosartorya fischeri</I> were evaluated in atmospheres of 0:30:70, 0.5:29.5:70, 1:29:70, 2:28:70, and 5:25:70, O₂:CO₂:N₂ over a 5-day period. Spores were cultured on antibiotic-supplemented potato dextrose agar (pH 5.6, a_w 0.95) and incubated at 25°C. All four molds germinated and grew at 0.5:29.5:70. Extent of mycelia growth diameter (mm) increased significantly (P<0.05) as oxygen concentration increased from 0.5% to 5%. All growth was inhibited at 0:30:70, but germination and growth occurred once cultures were exposed to 20.9% atmospheric O₂, indicating that a modified atmosphere containing no residual O₂ is fungistatic. Yeast and mold growth was seen in ultra-pasteurized (UP) extended shelf-life fluid milk stored at (7.2°C). Ten half-pint, pint, quart and half gallon filled cartons were randomly selected from all UP products available. Samples, pulled at random on day 0, 15, 30, 45, and 60, were plated on Yeast and Mold Petrifilm™. Forty-seven percent of the UP products stored for 45 days tested positive for mold. Fungal growth was apparent down the side and along the bottom of the 5th panel. Contamination was traced to the presence of yeast and mold spores in paperboard cartons. Pinholes were present in the polyethylene coating and wicking occurred at the unskived 5th panel. Fungi of similar origin and fatty acid profile were isolated from UP milk products and the paperboard cartons. / Ph. D.

The growth of Listeria monocytogenes and nonproteolytic Clostridium botulinum type B spores in cooked, uncured turkey was investigated separately under varying conditions of modified atmosphere packaging (MAP), refrigerated and temperature-abuse storage, and lactic acid bacteria (LAB) competition. L. monocytogenes (LM) growth was suppressed when initially outnumbered 3.5 logs:1 or 2.1 logs:1 by naturally-occurring LAB, but not when the initial LAB:LM population ratio was equivalent. Lowering storage temperature from 10 degrees to 4 degrees C enhanced the inhibitory effect of CO₂ in the packaging atmosphere, and extended the period of product olfactory acceptability. When the LAB:LM population ratio was equivalent, objectionable odors were not detected in most of the samples, despite LAB counts in excess of 10E⁸/g. This raises concerns with respect to public health, since high levels of L. monocytogenes can be present in MAP meat and poultry products without accompanying signs of overt spoilage. Cellular fatty acid (CFA) analysis was a valuable tool for distinguishing between phenotypically distinct isolates of LM inoculated into MAP turkey. Fatty acid composition of foodborne outbreak-associated (serotype 4) and non-outbreak-associated (serotype 1) strains of LM correlated with antigenic type (4 or 1) and agglutination reaction (granular or flocculent). Strain ATCC 43256 (serotype 4b) produced a consistently unique CFA profile, making it the easiest of the four test strains to be differentiated. Analysis of additional LM serotypes, as well as examination of existing clinical and environmental CFA databases for correlations between fatty acid profiles and diagnostic characteristics of LM, is necessary before CFA analysis can be effectively applied as an epidemiological tool for tracking the distribution of LM strains in food products and throughout the farm-to-table food chain. Reduced storage temperature significantly delayed botulinal toxin production and extended the period of olfactory acceptability of cooked turkey, but even strict refrigeration did not prevent growth and toxigenesis by nonproteolytic C. botulinum type B. Toxin was detected on day 7 for product stored at 15 degrees C and on day 14 for product stored at 10 degrees C, irrespective of packaging atmosphere. At 4 degrees C, toxin was detected on day 14 for product packaged without carbon dioxide, and on day 28 for product packaged with 30% carbon dioxide. At all three storage temperatures, toxin detection preceded or coincided with olfactory unacceptability, demonstrating the potential for consumption of toxic product when spoilage-signalling sensory cues are absent. / Ph. D.

Durante los últimos años la creciente demanda por parte del consumidor de alimentos frescos, de primera calidad y listos para preparar y servir, ha generado un cambio importante en la aplicación de técnicas de conservación de alimentos, abriéndose nuevas líneas en el mercado. Ante este reto, la industria ha respondido mediante la elaboración de productos minimamente procesados en fresco. Sin embargo, estos alimentos presentan una vida útil corta, principalmente debido a problemas de pardeamiento. La metodología para controlar este tipo de problema se basa en la utilización de antioxidantes y atmósferas modificadas con bajo nivel de O2. Sin embargo, la sola aplicación de estas tecnologías, en muchos casos, resulta poco efectiva para garantizar una vida útil adecuada del producto minimamente procesado. Por lo tanto, resulta necesario seguir estudiando en el desarrollo y aplicación de otras tecnologías que ayuden a mantener la calidad de estos productos durante periodos adecuados para su comercialización. En este proyecto, se pretende estudiar la efectividad de tratamientos antioxidantes con recubrimientos comestibles y el envasado en atmósferas modificadas `no convencionales¿, con el objetivo de reducir el pardeamiento enzimático en productos como alcachofa, berenjena, manzana y caqui minimamente procesados. / Ghidelli, C. (2014). EFFECT OF SOY PROTEIN-BASED EDIBLE COATINGS WITH ANTIOXIDANT ACTIVITY AND MODIFIED ATMOSPHERE PACKAGING ON THE QUALITY OF FRESH-CUT PRODUCES [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/39104

The mango (Mangifera indica L.) is an appealing subtropical fresh fruit with a pleasant flavor and taste, high nutritional value, beneficial medicinal properties and various processing options. However, as is the case with most subtropical fruit, it is a sensitive commodity, prone to losses postharvestly. The South African mango industry is highly dependent on a hot water and cold prochloraz dip treatment, to control postharvest anthracnose and soft brown rot on fruit destined for export. However, negatve public perceptions of synthetic fungicides and its use on fresh produce for disease control has been increasing in major export markets such as the European Union. This growing concern from a public point of view is forcing industry to consider more environmentally acceptable methods to maintain quality of mangoes during extended export periods. ‘Tommy Atkins’ and ‘Kent’ mangoes either uninoculated or artificially inoculated with Colletotrichum gloesporioiedes, Botryosphaeria parva or sterile agar, were used to evaluate softer, greener alternatives, in this study. Fruit were subjected to either a hot, Bacillus amyloliquefaciens (PPCB004) containing dip treatment for two minutes or a 24 hour 1-methylcyclopropene (1-MCP) gas treatment at 16 ºC or no treatment. Fruit were then stored at 10 ºC under either 5% O2 and 5% CO2 (CA-1) or 3% O2 and 8% CO2 (CA-2) controlled atmospheres (CA) for 18 days and allowed to ripen for five days at 25 ºC. Similarly, uninoculated or artificially inoculated fruit subjected to B. amyloliquefaciens, 1-MCP or a combination of the two treatments was stored at 10 ºC for 18 days under conventional storage. ‘Tommy Atkins’ fruit were packed into bags made from four different film types, untreated or after being subjected to a cold B. amyloliquefaciens dip treatment and stored for 23 days at 10 ºC. Overall, ‘Kent’ fruit were more susceptible to anthracnose and SBR after artificial inoculation. In vivo inoculated ‘Tommy Atkins’ fruit, storage under CA-1 gave the best control of soft brown rot whilst CA-2 storage gave the best control of anthracnose. For quality retention no definite conclusion could be made for both cultivars after CA storage or the combination of 1-MCP pre-treatment and CA storage. The combination of 1-MCP pre-treatment and B. amyloliquefaciens maintained the quality of ‘Kent’ mangoes under conventional storage the best. Anthracnose severity on both cultivars was reduced with 1-MCP treated fruit combined with the biocontrol pre-treatment. Modified atmosphere packaging in this study was found to be ineffective in maintaining quality of mangoes. Copyright / Dissertation (MSc(Agric))--University of Pretoria, 2011. / Microbiology and Plant Pathology / unrestricted