Orientador: Walkíria Hanada Viotto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-21T19:46:50Z (GMT). No. of bitstreams: 1 Antunes_VeridianadeCarvalho_D.pdf: 594153 bytes, checksum: 10f4a5a4748fcd7e3ce583bf9de1f46f (MD5) Previous issue date: 2013 / Resumo: A extensão da vida de prateleira do leite pasteurizado é um desafio e uma necessidade para a indústria de laticínios. A microfiltração tem sido utilizada para remoção de micro-organismos e aumento da qualidade e vida de prateleira de leite fluido, sendo geralmente realizada em membranas cerâmicas sob o conceito de Pressão Transmembranar Uniforme (PTU). O objetivo desse trabalho foi avaliar o desempenho de um novo tipo de membrana (Isoflux®) capaz de manter o fluxo de permeado constante ao longo do comprimento da membrana e também o efeito do armazenamento refrigerado e da microfiltração na qualidade e vida útil do leite pasteurizado. O desempenho da membrana Isoflux , na microfiltração do leite cru, foi avaliado através da determinação do fluxo de permeado, retenção de células somáticas, microorganismos, gordura e caseína. Em geral, o fluxo da membrana estudada foi baixo, variando de 130 a 200 Kg/h/m2. A retenção de micro-organismos mesófilos e psicrotróficos foi maior que 99%, enquanto a retenção de coliformes foi de 90%, e de 100% para células somáticas. A membrana reteve, em média, 11,2% de caseína e 34,6% de gordura. O efeito do armazenamento refrigerado do leite cru (7 ºC/ 6 dias) e o impacto da microfiltração na microbiota, qualidade e vida de prateleira do leite pasteurizado foram avaliados pela contagem de micro-organismos mesófilos, psicrotróficos e coliformes, pelas alterações físicoquímicas (pH, acidez titulável e viscosidade), atividade proteolítica, ocorrência de sabor amargo e aceitação sensorial durante o tempo de armazenamento. Houve um aumento de 2,15 ciclos logarítmicos no número de micro-organismos mesófilos e de 2,55 ciclos para os psicrotróficos, após o armazenamento do leite cru a 7 °C/6 dias. Durante esse tempo, não houve alteração na composição do leite e sua viscosidade permaneceu constante. A microfiltração reduziu em 3 e 4 ciclos logarítmicos a contagem inicial de micro-organismos mesófilos e psicrotróficos, respectivamente. Não foi observada diferença significativa na atividade proteolítica, na viscosidade e no perfil sensorial do leite microfiltrado pasteurizado, durante a vida de prateleira do produto. O produto apresentou boa aceitação sensorial com média de 6,31 para o atributo sabor, sendo que mais de 50 % dos provadores certamente ou provavelmente comprariam o produto, durante toda sua vida de prateleira, independente de ser obtido de leite controle ou com armazenamento refrigerado prévio (7 °C/6 d). O gosto amargo aumentou com o tempo de armazenamento, mas não atingiu níveis que resultassem em rejeição do produto. Aos 15 dias de armazenamento refrigerado, o leite microfiltrado pasteurizado atingiu uma contagem de micro-organismos mesófilos de 3 x 104UFC/mL, o que determinou o fim da sua vida de prateleira. A microfiltração aliada à pasteurização proporcionou a obtenção de um produto com maior vida útil de prateleira, mesmo quando proveniente de leite cru refrigerado armazenado a 7 ºC por 6 dias / Abstract: Extending the shelf life of pasteurized milk is a challenge and a necessity for the dairy industry. The microfiltration has been utilized for the removal of microorganisms and increase the quality and shelf life of liquid milk, usually being held in ceramic membranes under the concept of uniform transmembrane pressure. A new membrane, Isoflux , with modified thickness of the separating layer, is claimed to maintain a nearly constant permeate flux along the length of the membrane. The performance of membrane Isoflux on the microfiltration of skim milk and the influence of concentration factor on the components retention by the membrane was evaluated. Permeate flux, reduction of bacteria and somatic cells, and partition of the main components of milk permeate and retentate during milk Microfiltration (MF) were determined. In general, the flux of membrane studied was low, varying with 130 a 200 Kg/h/m². The retention of mesophilic and psychrotrophic microorganisms was greater than 99%, 90% for coliforms, and 100% of somatic cells. The membrane retained, on average, 11.2% of casein and 34.6% fat. In general, the flux of the Isoflux® membrane was low, ranging 130-200 Kg/hm2. The new technical regulations require that raw milk is refrigerated on the farm. The effect of refrigerated storage of raw milk and the impact of the microfiltration on the microbiological quality and shelf life of pasteurized milk was assessed by bacterial counts (mesophilic, psychrotrophic and coliforms), physico-chemical changes (pH, titratable acidity, viscosity), proteolytic activity, the development of bitter taste and sensory acceptance during the storage time. There was an increase of 2.15 log in the number of mesophilic bacteria and of 2.55 log for psychrotrophic microrganisms after the storage of raw milk to 7 ° C/6 days. No changes in raw milk composition and viscosity occurred during the refrigerated storage. The microfiltration reduced by 3 log the initial count of mesophilic and up to 4 log the number of psychrotrophic microorganisms. There was no significant proteolytic activity, nor changes in viscosity or relevant sensory changes that might interfere with the sensory acceptance of microfiltered pasteurized milk during the 15 days of storage. The product had good acceptability with an average of 6.31 for the attribute flavor, with more than 50% of the panelists certainly or probably buy the product throughout its shelf life, whether it be milk obtained from control or refrigerated raw milk (7 ° C/6 d). The bitter taste increased with storage time, but did not reach levels that would result in rejection of the product. At 15 days of refrigerated storage, microfiltered pasteurized milk reached a mesophiles count of 3 x 104 CFU/mL, which determined the end of its shelf life / Doutorado / Tecnologia de Alimentos / Doutora em Tecnologia de Alimentos

La mûre tropicale de montagne (Rubus adenotrichos Schltdl.) est largement cultivée et consommée au Costa Rica. Cependant, il existe peu de recherches scientifiques sur ce fruit. Par conséquent, nos travaux ont pour but de valoriser la mûre au travers de l’étude de ses activités biologiques sur le syndrome métabolique. Le jus microfiltré de mûre a démontré être riche en polyphénols (377,5 équivalents d’AG/100g), spécialement en ellagitanins (90,39-141,89 équivalents d’AE/100g) et anthocyanes (56,93-73,31 équivalents de cyanidine-3-glucoside/100g). Le pouvoir antioxydant du jus de mûre a été déterminé par les méthodes ORAC (4253,53 µmol ET/100g), FRAP (4703,84 µmol ET/100g), ABTS (1,075 μmol ET/100g) et LPO (15,88 µM de hydroperoxyde) et par des mesures de la capacité antioxydante des enzymes superoxyde dismutase (767,33 U/ml) et catalaseCAT (70,33 nmol/min/ml). Le jus de mûre a inhibé la production du NO induite par LPS+IFNγ lorsqu'il a été utilisé comme prétraitement sur les cellules J774A.1. L’inhibition a été de 51,95% pour le jus de mûre à 1000 g/ml, sans affecter ni la viabilité cellulaire ni la concentration de protéines dans les cellules. Cette activité antiinflammatoire a été confirmée par la diminution du taux de la synthase inductible de l'oxyde nitrique dans ces mêmes cellules par une analyse Western Blot. Cette étude a utilisé un modèle in vivo pour évaluer l'effet de la consommation du jus de mûre chez des rats insulino-résistants. L'apport en mûre a provoqué une diminution des triglycérides sériques (-50,2%), du cholestérol total (-15,6%), du cholestérol LDL (-48,2%) et de la pression artérielle systolique des rats par rapport aux témoins, sans influencer les concentrations de cholestérol HDL ni la glycémie. L’effet hypotenseur du jus a été confirmé par une réduction de la pression artérielle diastolique de 54,2% lors de la mesure de la pression artérielle après l’injection du jus de mûre chez le rat anesthésié. L’effet du jus de mûre chez homme a été évalué lors d’un essai clinique avec des patients dislypidémiques, après lequel on a observé une réduction significative du tour de taille, du glucose, de la pression artérielle diastolique et des triglycérides (-20,3%) chez les patients qui ont consommé du jus de mûre à 40% v/v durant 6 semaines. En outre, lors de la fermentation du jus de mûre costaricienne avec des levures du type Saccharomyces cerevisiae, la teneur en sucres (glucose, fructose et saccharose) a été réduite presque totalement au bout de 10 jours et le séchage par atomisation d’un jus fermenté avec 10% de maltodextrine 6DE et 1% de Aerosil, à un débit de pulvérisation de 3 ml/min et avec un débit d’air chaud (150°C) de 650 L/h garantit l’obtention d’une poudre avec un rendement élevé de séchage. Enfin, cette étude suggère que la mûre Rubus adenotrichos présente un bénéfice potentiel sur la santé, spécialement contre toutes les pathologies liées au syndrome métabolique. Mots clés: Rubus adenotrichos, mûre, jus microfiltré, syndrome métabolique, dyslipidémie, antioxydante, antiinflammatoire, hypotension / Tropical highland blackberry (Rubus adenotrichos Schltdl.) is widely cultivated and consumed in Costa Rica. However, there is little scientific research on this fruit. Therefore, our work aims to enhance blackberry importance through the study of its biological activity on the metabolic syndrome.Blackberry microfiltered juice has been shown to be rich in polyphenols (377.5 GA equivalents /100g), especially ellagitannins (from 90.39 to 141.89 EA equivalents/100g) and anthocyanins (from 56.93 to 73, 31 equivalents of cyanidin-3-glucoside/100g). The antioxidant power of blackberry juice was determined by the ORAC (4253.53 µmol TE/100g), FRAP (4703.84 µmol TE/ 100g), ABTS (1.075 µmol TE/100g) and LPO (15.88 µmol of hydroperoxide) methods and by measuring the antioxidant capacity of superoxide dismutase (767.33 U/ml) and catalase (70.33 nmol/min/ml) enzymes.Blackberry juice inhibited NO production induced by LPS+IFN gamma when used as a pretreatment on J774A.1 cells. Inhibition was 51.95% for the blackberry juice at 1000 µg/ml, without affecting neither cell viability nor the concentration of proteins in J774A.1 cells. The anti-inflammatory activity has been confirmed by the decrease in the rate of inducible nitric oxide synthase in these cells by Western blot analysis.This study used an in vivo model to assess the effect of blackberry juice consumption in insulin-resistant rats. The intake of blackberry caused a decrease in serum triglycerides (-50.2%), total cholesterol (-15.6%), LDL cholesterol (-48.2%) and in the systolic blood pressure of rats compared to controls, without affecting HDL cholesterol or blood sugar levels. The hypotensive effect of the juice has been confirmed by a reduction of 54.2% of the diastolic blood pressure in the measurement of blood pressure after injection of the blackberry juice in the anesthetized rat.The effect of blackberry juice on humans was evaluated in a clinical trial with patients suffering dyslipidemia, after which a significant reduction in waist circumference, glucose, diastolic blood pressure and triglycerides (-20,3%) was observed in patients who consumed 40% v/v blackberry juice for 6 weeks.Also, during fermentation of blackberry juice with yeasts of the Saccharomyces cerevisiae type, the sugar content (glucose, fructose and sucrose) was reduced almost totally after 10 days and the spray drying of the fermented juice with 10% maltodextrin 6DE and 1% Aerosil, at a spraying rate of 3 ml/min and with a flow of hot air (150°C) of 650 L/h ensures to obtain a powder and a high efficiency in drying.Finally, this study suggests that the blackberry specie Rubus adenotrichos presents a potential health benefit, especially against all diseases related to metabolic syndrome.Keywords: Rubus adenotrichos, blackberry, microfiltered juice, metabolic syndrome, dyslipidemia, antioxidant, anti-inflammatory, hypotension