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ABSTRACT: The effects of gamma irradiation and pasteurization on the stability of anthocyanins and antioxidant capacity during storage of jussara pulp were investigated. Jussara pulp was divided into 6 portions: control (no treatment), irradiated pulp (2, 4, 6, 8 kGy) and pasteurized pulp (92 ºC/ 1 minute). Portions were stored at 4ºC for 60 days. The phenolic extract was prepared with a solution of methanol/water/formic acid. The following analyses were performed every 15 days: contents of total phenolic compounds by Folin-Ciocauteau, cyanidin-3-glycoside and cyanidin-3-rutiniside by HPLC and antioxidant capacity (ABTS and DPPH). Total phenolics and anthocyanins decreased with the increasing irradiation dose and storage time. Pasteurization did not affect the phenolic concentration immediately after processing. However, the contents of TPC and cyanidin-3-rutiniside were reduced during storage of the pasteurized pulp. No processed samples presented characteristics similar to the control at the end of storage.

RESUMO: Os efeitos da radiação gama e pasteurização na estabilidade das antocianinas e na capacidade antioxidante durante o armazenamento da polpa de jussara foram avaliados. A polpa de jussara foi dividida em diferentes tratamentos: controle (sem tratamento), polpa irradiada (2, 4, 6, 8 kGy) e pasteurizada polpa (92 ºC / 1 minuto). Os tratamentos foram armazenados a 4ºC por 60 dias. O extrato fenólico foi preparado com uma solução de metanol / água / ácido fórmico. As seguintes análises foram realizadas a cada 15 dias: teores de compostos fenólicos totais por Folin-Ciocauteau, cianidina 51 3-glicosídeo e cianidina-3-rutinisida por HPLC e capacidade antioxidante (ABTS e DPPH). Os fenólicos totais e as antocianinas diminuíram com o aumento da dose de irradiação e do tempo de armazenamento. A pasteurização não afetou a concentração fenólica imediatamente após o processamento. No entanto, os teores de TPC e cianidina-3-rutinisida foram reduzidos durante o armazenamento da polpa pasteurizada. Nenhuma amostra processada apresentou características semelhantes ao controle ao final do armazenamento.

RESUMO

ABSTRACT: This research assessed the phenolic composition of Jussara pulp from the Brazilian states of Minas Gerais (MG) and Espírito Santo (ES) using HPLC-DAD-MS/MS. Seventeen anthocyanins were detected in fruits, derived from cyanidin, pelargonidin and peonidin. Among the non-anthocyanic phenolic compounds, flavonols (kaempferol, quercetin and isorhamnetin derivatives), flavan-3-ols (catechin, epicatechin, B-type procyanidins and unknown dimers) and resveratrol in its glycosylated form have been identified. Catechin (32.41-60.56 mg 100g-1) and epicatechin (18.86-40.92 mg 100g-1) were the main flavan-3-ols present in the fruits. The samples showed small concentrations of resveratrol glycosides (0.02-0.91 mg 100g-1). The analytical methodology used (HPLC-DAD-ESI-MS/MS) permitted the identification of newly reported compounds in this fruit.

RESUMO: O objetivo desta pesquisa foi avaliar a composição fenólica da polpa de Jussara dos Estados brasileiros de Minas Gerais (MG) e Espírito Santo (ES) usando HPLC-DAD-MS / MS. Dezessete antocianinas foram detectadas, dentre elas, derivadas de cianidina, pelargonidina e peonidina. Dentre os compostos fenólicos não antociânicos, foram identificados flavonóis (derivados de caempferol, quercetina e isorhamnetina), flavan-3-ols (catequina, epicatequina, procianidinas do tipo B e dímeros desconhecidos) e resveratrol em sua forma glicosilada. Catequina (32,41-60,56 mg 100g-1) e epicatequina (18,86-40,92 mg 100g-1) foram os principais flavan-3-óis presentes nas frutas. As amostras apresentaram pequenas concentrações de glicosídeos resveratrol (0,02-0,91 mg 100g-1). A metodologia analítica utilizada (HPLC-DAD-ESI-MS / MS) permitiu a identificação de novos compostos relatados presentes na composição da polpa de Jussara.

RESUMO

The effects of gamma irradiation and pasteurization on the stability of anthocyanins and antioxidant capacity during storage of jussara pulp were investigated. Jussara pulp was divided into 6 portions: control (no treatment), irradiated pulp (2, 4, 6, 8 kGy) and pasteurized pulp (92 ºC/ 1 minute). Portions were stored at 4ºC for 60 days. The phenolic extract was prepared with a solution of methanol/water/formic acid. The following analyses were performed every 15 days: contents of total phenolic compounds by Folin-Ciocauteau, cyanidin-3-glycoside and cyanidin-3-rutiniside by HPLC and antioxidant capacity (ABTS and DPPH). Total phenolics and anthocyanins decreased with the increasing irradiation dose and storage time. Pasteurization did not affect the phenolic concentration immediately after processing. However, the contents of TPC and cyanidin-3-rutiniside were reduced during storage of the pasteurized pulp. No processed samples presented characteristics similar to the control at the end of storage.

Os efeitos da radiação gama e pasteurização na estabilidade das antocianinas e na capacidade antioxidante durante o armazenamento da polpa de jussara foram avaliados. A polpa de jussara foi dividida em diferentes tratamentos: controle (sem tratamento), polpa irradiada (2, 4, 6, 8 kGy) e pasteurizada polpa (92 ºC / 1 minuto). Os tratamentos foram armazenados a 4ºC por 60 dias. O extrato fenólico foi preparado com uma solução de metanol / água / ácido fórmico. As seguintes análises foram realizadas a cada 15 dias: teores de compostos fenólicos totais por Folin-Ciocauteau, cianidina 51 3-glicosídeo e cianidina-3-rutinisida por HPLC e capacidade antioxidante (ABTS e DPPH). Os fenólicos totais e as antocianinas diminuíram com o aumento da dose de irradiação e do tempo de armazenamento. A pasteurização não afetou a concentração fenólica imediatamente após o processamento. No entanto, os teores de TPC e cianidina-3-rutinisida foram reduzidos durante o armazenamento da polpa pasteurizada. Nenhuma amostra processada apresentou características semelhantes ao controle ao final do armazenamento.

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Ultrasound (US) combined with chemical agents could represent an effective method for decontaminating fruits and vegetables. This study aimed to evaluate the use of US (40 kHz for 5 min) alone or with 1% lactic acid (LA), 1% commercial detergent (DET), or 6 mg/L silver nanoparticles (AgNP, average diameter 100 nm) as an alternative treatment to 200 mg/L sodium dichloroisocyanurate for inactivating Salmonella enterica serovar Enteritidis present on cherry tomatoes. The interfacial tension between sanitizing solutions and bacterial adhesion was investigated. Sanitizers in solutions with DET and AgNP had lower surface tension. All treatments, except that with DET, reduced Salmonella Enteritidis by more than one logarithmic cycle. There was no significant difference between the mean values of log colony-forming units (CFU)/g reduction in all treatments. Transmission electron microscopy revealed the loss of the Salmonella Enteritidis capsule following treatment with US and with US + LA. Salmonella Enteritidis counts (2.29 log CFU/g) in cherry tomatoes were markedly reduced to safe levels by treatment with the combination of AgNP and US + LA (2.37 log CFU/g).

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This study evaluated the viability of Lactobacillus rhamnosus GG (LGG) and its in vitro and in vivo resistance to the gastrointestinal tract (GIT) when carried by a mixed fermented pineapple and jussara juice. The effects of product ingestion on the biochemical characteristics of the blood and on the development of aberrant crypt foci (ACF) in Wistar rats were also determined. The LGG viability in probiotic juice was higher than 7.2 log CFU/mL throughout 28 days at 8 °C. The mean count of the probiotic microorganism in the fecal samples of the rats was 5.6 log CFU/g, identical to the count at the end of the in vitro trial (enteric phase II), indicating that the mixed pineapple and jussara juice was an excellent vehicle for LGG. No difference (p > .05) was verified to ACF among the groups. However, the results for the probiotic culture viability and its in vitro and in vivo resistance to the gastrointestinal tract suggest that this juice is an excellent carrier matrix for LGG and contributed to a reduction in the levels of the LDL (low density lipoprotein) fraction of the blood cholesterol, thus being an aid in the control of coronary diseases.

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This study evaluated the viability of Lactobacillus acidophilus La-05, Lactobacillus plantarum LP299v and Lactobacillus rhamnosus GG in tropical mango juice, the resistance of the strains to gastrointestinal conditions simulated in vitro and the microbiological, physicochemical and sensory characteristics of the products obtained. The viabilities of L. rhamnosus GG and L. plantarum LP299v were greater than 7.96 log CFU mL <->1 and 7.74 log CFU mL <->1, respectively, during the 28 days of storage at 8 ºC. However, there was a reduction (p < 0.05) in the viability of L. acidophilus La-5 after 21 days of storage, with counts of 3.81 log UFC mL <->1. The parameters of pH, total soluble solids, luminosity (L*) and the color coordinates, a* and b*, did not differ between the treatments. However, the pH and acidity varied during the storage time, probably due to the fermentative action of the microorganisms. For the in vitro gastrointestinal resistance test, there was a difference in the gastric phase for enteric phases I and II. The mean viability of the microorganisms in the gastric phase was 5.11 log CFU mL <->1, decreasing to 4.02 and 3.97 log CFU mL <->1 in enteric phases I and II, respectively. Juices containing L. rhamnosus GG and L. plantarum LP299 were evaluated sensorially, presenting good acceptability. The results suggest that the tropical mango juice was a good carrier matrix for L. rhamnosus GG and L. plantarum LP 299v, being well accepted and therefore an alternative for populations with dietary restrictions.(AU)

Este estudo avaliou a viabilidade de Lactobacillus acidophilus La-05, Lactobacillus plantarum LP299v e Lactobacillus rhamnosus GG em suco tropical de manga, a resistência das estirpes às condições gastrointestinais simuladas em ensaio in vitro e as características microbiológicas, físico-químicas e sensoriais dos produtos obtidos. A viabilidade de L. rhamnosus GG e L. plantarum LP299v foi superior a 7,96 log UFC mL <->1 e 7,74 log UFC mL <->1, respectivamente, ao longo dos 28 dias de armazenamento a 8 ºC. Entretanto, houve redução (p < 0,05) da viabilidade de L. acidophilus La-5 após 21 dias de armazenamento, com contagens de 3,81 log UFC mL <->1. pH, sólidos solúveis totais, luminosidade (L*) e as coordenadas a* e b* não diferiram entre os tratamentos. Entretanto, houve diferença de pH e acidez ao longo do tempo de armazenamento provavelmente devido a ação fermentativa dos microrganismos. No ensaio in vitro de resistência gastrointestinal, houve diferença da fase gástrica para as fases entéricas I e II. A média da viabilidade dos microrganismos na fase gástrica foi de 5,11 log UFC mL <->1, decaindo para 4,02 e 3,97 log UFC mL <->1 nas fases entéricas I e II, respectivamente. Os sucos contendo L. rhamnosus GG e L. plantarum LP299 foram avaliados sensorialmente, apresentando boa aceitabilidade. Os resultados de viabilidade e resistência ao trato gastrointestinal simulado in vitro sugerem que o suco tropical de manga é uma ótima matriz carreadora de L. rhamnosus GG e L. plantarum LP 299v, sendo bem aceitos e, portanto, uma alternativa para a população que apresenta restrições na dieta.(AU)

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RESUMO

This study evaluated the viability of Lactobacillus acidophilus La-05, Lactobacillus plantarum LP299v and Lactobacillus rhamnosus GG in tropical mango juice, the resistance of the strains to gastrointestinal conditions simulated in vitro and the microbiological, physicochemical and sensory characteristics of the products obtained. The viabilities of L. rhamnosus GG and L. plantarum LP299v were greater than 7.96 log CFU mL

Este estudo avaliou a viabilidade de Lactobacillus acidophilus La-05, Lactobacillus plantarum LP299v e Lactobacillus rhamnosus GG em suco tropical de manga, a resistência das estirpes às condições gastrointestinais simuladas em ensaio in vitro e as características microbiológicas, físico-químicas e sensoriais dos produtos obtidos. A viabilidade de L. rhamnosus GG e L. plantarum LP299v foi superior a 7,96 log UFC mL

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The viability of Lactobacillus rhamnosus GG (LGG) in jabuticaba juices and its survival in the gastrointestinal tract (GIT), simulated in vitro, was studied. Two juices were prepared: A with nonblanched fruits, and B with blanched fruits. LGG was then added and the juices maintained at 8 ºC for 28 days. The control treatment consisted of juices without the added probiotic. The following were determined in the juices: the viability and in vitro survival of LGG, fecal coliforms, Salmonella sp., pH, acidity, total soluble solids (TSS), color, antioxidant capacity, total phenolic compounds, anthocyanins and ascorbic acid. The sensory acceptability was also determined using a 9-point hedonic scale. Blanching interfered (p < 0.05) with the viability of LGG, juice A showing the greatest viability as compared to juice B. After in vitro simulation, the probiotic bacterial count was < 1.0 log CFU mL-1, which demonstrates the low resistance of the strain to the simulated GIT conditions. The juices were conformed to the microbiological standards established by law. The pH, acidity and TSS were influenced by blanching (p < 0.05), with values of 5.03, 0.46% and 15.38 °Brix for juice A and 5.12, 0.66% and 16.05 °Brix for juice B, respectively. The addition of LGG did not influence these characteristics. Only the pH value was influenced by the storage time (p < 0.05), increasing throughout storage. Juice B showed lower luminosity (L*) and a greater value for a* as compared to juice A, indicating that the former became darker and redder due to the blanching process. Both juices showed positive values for the b* coordinate. The juice was found to be a good source of polyphenols. Neither the time nor the addition of LGG affected the antioxidant capacity, total phenolic compounds or anthocyanin contents...(AU)

A viabilidade de Lactobacillus rhamnosus GG (LGG) em sucos de jabuticaba e sua sobrevivência ao trato gastrointestinal (TGI) simulado in vitro foram estudadas. Foram preparados dois sucos: A (com frutas não branqueadas) e B (com frutas branqueadas), os quais foram adicionados de LGG e mantidos a 8 °C durante 28 dias. O tratamento controle consistiu dos sucos sem adição de probiótico. Determinouse a viabilidade e a sobrevivência in vitro de LGG nos sucos, coliformes termotolerantes, Salmonella sp., pH, acidez, sólidos solúveis totais (SST), cor, capacidade antioxidante, compostos fenólicos totais, antocianinas totais e ácido ascórbico, além da aceitabilidade em escala hedônica de 9 pontos. O branqueamento interferiu (p < 0,05) na viabilidade de LGG, sendo que o suco A apresentou maior viabilidade desta bactéria comparado ao suco B. A contagem de LGG após a simulação da sobrevivência in vitro foi < 1,0 Log UFC mL-1 estimado, demonstrando a baixa resistência da estirpe às condições do TGI simulado quando veiculado pelos sucos de jabuticaba. Os sucos atenderam aos padrões microbiológicos estabelecidos pela legislação. O pH, acidez e SST dos sucos foram influenciados pelo branqueamento (p < 0,05), sendo os valores médios de 5,03, 0,46%, 15,38 °Brix para os sucos A e 5,12, 0,66% e 16,05 °Brix para os sucos B, respectivamente. A adição do probiótico não influenciou estas características (p > 0,05). Os sucos B apresentaram menor luminosidade (L*) e maior valor de a* com coloração mais escura e avermelhada. Ambos os sucos apresentaram valores positivos para a coordenada b*. Os sucos revelaram ser fonte de compostos fenólicos como antocianinas, responsáveis pela considerável capacidade antioxidante dos produtos. Não foi observado efeito do tempo e da adição de LGG na capacidade antioxidante, compostos fenólicos totais e antocianinas...(AU)

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RESUMO

The viability of Lactobacillus rhamnosus GG (LGG) in jabuticaba juices and its survival in the gastrointestinal tract (GIT), simulated in vitro, was studied. Two juices were prepared: A – with nonblanched fruits, and B – with blanched fruits. LGG was then added and the juices maintained at 8 ºC for 28 days. The control treatment consisted of juices without the added probiotic. The following were determined in the juices: the viability and in vitro survival of LGG, fecal coliforms, Salmonella sp., pH, acidity, total soluble solids (TSS), color, antioxidant capacity, total phenolic compounds, anthocyanins and ascorbic acid. The sensory acceptability was also determined using a 9-point hedonic scale. Blanching interfered (p < 0.05) with the viability of LGG, juice A showing the greatest viability as compared to juice B. After in vitro simulation, the probiotic bacterial count was < 1.0 log CFU mL-1, which demonstrates the low resistance of the strain to the simulated GIT conditions. The juices were conformed to the microbiological standards established by law. The pH, acidity and TSS were influenced by blanching (p < 0.05), with values of 5.03, 0.46% and 15.38 °Brix for juice A and 5.12, 0.66% and 16.05 °Brix for juice B, respectively. The addition of LGG did not influence these characteristics. Only the pH value was influenced by the storage time (p < 0.05), increasing throughout storage. Juice B showed lower luminosity (L*) and a greater value for a* as compared to juice A, indicating that the former became darker and redder due to the blanching process. Both juices showed positive values for the b* coordinate. The juice was found to be a good source of polyphenols. Neither the time nor the addition of LGG affected the antioxidant capacity, total phenolic compounds or anthocyanin contents...

A viabilidade de Lactobacillus rhamnosus GG (LGG) em sucos de jabuticaba e sua sobrevivência ao trato gastrointestinal (TGI) simulado in vitro foram estudadas. Foram preparados dois sucos: A (com frutas não branqueadas) e B (com frutas branqueadas), os quais foram adicionados de LGG e mantidos a 8 °C durante 28 dias. O tratamento controle consistiu dos sucos sem adição de probiótico. Determinouse a viabilidade e a sobrevivência in vitro de LGG nos sucos, coliformes termotolerantes, Salmonella sp., pH, acidez, sólidos solúveis totais (SST), cor, capacidade antioxidante, compostos fenólicos totais, antocianinas totais e ácido ascórbico, além da aceitabilidade em escala hedônica de 9 pontos. O branqueamento interferiu (p 0,05). Os sucos B apresentaram menor luminosidade (L*) e maior valor de a* com coloração mais escura e avermelhada. Ambos os sucos apresentaram valores positivos para a coordenada b*. Os sucos revelaram ser fonte de compostos fenólicos como antocianinas, responsáveis pela considerável capacidade antioxidante dos produtos. Não foi observado efeito do tempo e da adição de LGG na capacidade antioxidante, compostos fenólicos totais e antocianinas...

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A demanda por uma alimentação saudável com alimentos frescos, especialmente frutas e hortaliças minimamente processadas, resultou em uma variedade de produtos disponíveis para os consumidores. Os benefícios nutricionais de bactérias láticas probióticas contribuem para aumentar o consumo de vegetais minimamente processados enriquecidos com estes micro-organismos em supermercados e restaurantes, uma vez que o consumidor moderno busca produtos de alta funcionalidade e segurança. O objetivo deste estudo foi avaliar a viabilidade de Lactobacillus rhamnosus HN001 em melão minimamente processado e determinar as propriedades microbiológicas e físico-químicas desse alimento. As contagens de L. rhamnosus estavam acima 108 UFC g-1 e a qualidade microbiológica dos melões estava segura para os consumidores. O pH diminuiu e a acidez aumentou ao longo do período de estocagem dos melões minimamente processados. Os sólidos solúveis não diferiram entre as amostras. As coordenadas de cor L * e a * não mudaram e a firmeza do melão diminuiu ao longo do tempo. A microscopia eletrônica de varredura revelou a adesão de L. rhamnosus HN001 na superfície do melão tratado. Apesar de algumas alterações físico-químicas, a produção de melão minimamente processado enriquecido com L. rhamnosus é viável e transforma-o em um potencial veículo de probióticos.(AU)

The demand for healthy diets with fresh foods, especially minimally processed fruits and vegetables, resulted in a variety of products available to consumers. The nutritional benefits of probiotic lactic acid bacteria contribute to increase consumption of minimally processed vegetables enriched with these microorganisms in supermarkets and restaurants, since the modern consumer search products of high functionality and safety. The aim of this study was to assess the viability of Lactobacillus rhamnosus HN001 on minimally processed yellow melon and determine the microbiological and physicochemical properties of this food. The counts of L. rhamnosus were above 108 CFU g-1, and the microbiological quality of melons was safe to consumers. The pH lowered and the acidity increased over time in minimally processed melons. The soluble solids did not differ between samples. The color coordinates L* and a* have not changed and melon firmness decreased over time. The scanning electron microscopy revealed adhesion of L. rhamnosus HN001 on the surface of treated melon. Despite some physicochemical changes, the production of minimally processed melon enriched with L. rhamnosus is feasible transforming it into a potential vehicle for probiotics.(AU)

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