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Made available in DSpace on 2022-04-28T19:08:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-04-25 The objective of this study was to evaluate the physiological characteristics of minimally processed yam on the application of edible coating of the starch associated with the addition of ascorbic acid. For this, the minimally processed yam was stored for 12 days at 8±1°C and it underwent five treatments: control - T1; coated only with edible starch - T2; coated only with 1% ascorbic acid - T3; coated with edible starch with 1% ascorbic acid - T4; and coated with 1% ascorbic acid and 1% citric acid - T5. Respiratory rate, evolution of C2H4 and the concentrations of CO2 and ethylene (C2H4) were analyzed. Coated treatments showed the end of the lower storage CO2 concentrations in relation to the treatment in which edible coating was not applied. It was also found that the treatments in which ascorbic acid was incorporated showed higher CO2 release, suggesting its influence as an antioxidant in the respiratory system. Regarding respiratory rate, after finishing the minimal processing were found lower values for treatments with lining, with an average 58% reduction in respiratory rate. After the 4th day, all treatments showed a constant behavior with respect to respiratory rate. Instituto Federal de Sergipe, Rodovia Juscelino Kubitschek, s/n Universidade Federal de Sergipe, Av. Marechal Rondon, s/n Jardim Rosa Elze Universidade Estadual Paulista Campus Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, s/n Universidade Estadual Paulista Campus Jaboticabal, Via de Acesso Prof. Paulo Donato Castellane, s/n

In this work, treatments with UV-C light (20 kJ m−2) and gaseous ozone (2 mg L−1 O3) were applied to minimally processed rocket (Eruca vesicaria subsp. Sativa) leaves to investigate their effects on the antioxidant capacity and antioxidant system throughout 8 ds at 5 °C. As control, water washing was used. On 8 d, the ascorbic acid content was reduced about 50% both control and treated samples. Treatments with 20 kJ UV-C m−2 or 2 mg L−1 O3, did not affect the phenolic content neither the total antioxidant capacity, remaining almost constants during storage. The phenylalanine ammonia lyase (PAL) activity had no significant variations during storage, in correlation with the content of phenolics. As to the enzymes involved in the antioxidant system, an increase in its superoxide dismutase (SOD) activity with respect to uncut rocket leaves was detected after the process. In turn, enzymes that remove H2O2 like ascorbate peroxidase (APX) and catalase (CAT) showed no significant changes. During storage at 5 °C, the SOD activity remained unchanged while APX and CAT showed a gradual increase in both treated and untreated samples. In conclusion, the UV-C and ozone treatments applied inhibited the growth of spoilage by bacteria as well as by yeasts, extended shelf-life, without exerting significant additional stress with respect to the cutting stage of the leaves, reason by which they did not trigger a greater activation of the antioxidant system. Fil: Gutierrez, Diego Ricardo. Universidad Nacional de Santiago del Estero. Facultad de Agronomía y Agroindustrias. Instituto de Ciencias y Tecnologías Alimentarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santiago del Estero. Universidad Nacional de Santiago del Estero. Centro de Investigaciones y Transferencia de Santiago del Estero; Argentina Fil: Chaves, Alicia Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentina Fil: Rodriguez, Silvia del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santiago del Estero. Universidad Nacional de Santiago del Estero. Centro de Investigaciones y Transferencia de Santiago del Estero; Argentina. Universidad Nacional de Santiago del Estero. Facultad de Agronomía y Agroindustrias. Instituto de Ciencias y Tecnologías Alimentarias; Argentina

Little information is available regarding the incorporation of dietary fiber into edible films and coatings. In this work, apple fiber and inulin were incorporated into polysaccharide-based (alginate, pectine and gellan gum) edible coating formulations and their effects on the quality attributes of fresh-cut apples were evaluated. Antioxidant properties, color, firmness, sensory quality and microbial growth of fresh-cut apple were studied during 16 days of storage at 4 °C. Results show that dietary fiber extracts incorporated to gellan gum, pectin and alginate-based coatings together with calcium chloride and ascorbic acid successfully maintained the firmness and color of coated fresh-cut apples in comparison with uncoated control samples, which presented severe texture softening and browning. The firmness of apple pieces coated with polysaccharide-based coating formulations incorporating apple fiber doubled, and sometimes tripled, that of uncoated samples. Any of the assayed coatings exhibited a positive effect on the sensory properties of fresh-cut apples. The incorporation of apple fiber, together with the use of ascorbic acid, contributed to keep the antioxidant potential of the fruit at least during the first week of storage. Furthermore, gellan gum coatings had a marked effect in reducing mesophilic and psychrophilic counts on fresh-cut apples throughout storage regardless the addition of dietary fibers. The results achieved demonstrate the feasibility of the addition of dietary fiber to edible coating formulations for increasing the nutritional value of fresh-cut apples without compromising their fresh-like quality attributes. Fil: Moreira, Maria del Rosario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata; Argentina Fil: Cassani, Lucía Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Departamento de Ingeniería Química; Argentina Fil: Martin Belloso, Olga. Universidad de Lleida; España Fil: Soliva Fortuny, Robert. Universidad de Lleida; España

Made available in DSpace on 2015-11-03T15:29:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-10-01. Added 1 bitstream(s) on 2015-11-04T10:16:19Z : No. of bitstreams: 1 S0102-05362014000400391.pdf: 384988 bytes, checksum: 43b04f5d56c4b479bd61f4257488cc25 (MD5) O objetivo deste trabalho foi avaliar o efeito do ácido ascórbico (AA) e do cloreto de cálcio (CaCl2) aplicado em imersão nas temperaturas de 20 e 40ºC, sobre as características físico-químicas e sensoriais do repolho minimamente processado e mantido sob refrigeração. Os repolhos foram cortados em fatias com espessura de 3 mm. As fatias foram imersas em hipoclorito de sódio (50 ppm) por 5 minutos para higienização. Foram realizados os tratamentos T1= testemunha (imersão em água por 5 min a 20ºC); T2= imersão em solução contendo AA a 1%, por 5 min a 20ºC; T3= imersão em solução contendo AA a 2%, por 5 min a 20ºC; T4= imersão em solução contendo CaCl2 a 1%, por 5 min a 20oC; T5= imersão em solução contendo CaCl2 a 2%, por 5 min a 20oC; T6= imersão em solução contendo CaCl2 a 1%, por 5 min a 40oC; T7= imersão em solução contendo CaCl2 a 2%, por 5 min a 40oC, com quatro repetições cada. Os produtos foram centrifugados por 1 minuto, embalados em bandejas de poliestireno expandido, recobertos com policloreto de vinila de 20 µm e mantidos a 6±1oC e UR de 85-90%, por oito dias. Observou-se pequena elevação dos valores de pH e acidez titulável e diminuição nos teores de sólidos solúveis durante o período de conservação, independente do tratamento. O tratamento com AA não diferiu da testemunha quanto a cor e aparência geral, enquanto que o tratamento com CaCl2 2% a 20oC foi o que melhor manteve a qualidade, com menor escurecimento, as melhores notas para aparência geral e intenção de compra e menor odor estranho no final do período de conservação The objective of this trial was to evaluate the effect of ascorbic acid (AA) and calcium chloride (CaCl2) applied by immersion at temperatures of 20 and 40 degrees C on the physicochemical and sensory characteristics of minimally processed cabbage, stored under refrigeration. Cabbages were processed in an industrial food processing equipment to be cut in slices with thickness of 3 mm. Slices were immersed in sodium hypochlorite (50 ppm) during 5 minutes for sanitization. After, the following treatments were carried out T1= control (immersion in water during 5 minutes at 20 degrees C); T2= immersion in 1% AA solution, during 5 minutes at 20 degrees C; T3= immersion in 2% AA solution, during 5 minutes at 20 degrees C; T4= immersion in 1% CaCl2 solution during 5 minutes at 20 degrees C; T5= immersion in 2% CaCl2 solution during 5 minutes at 20 degrees C, T6= immersion in 1% CaCl2 solution during 5 minutes at 40 degrees C; and T7= immersion in 2% CaCl2 solution during 5 minutes at 40 degrees C; with four replications each one. After application of treatments, cabbage was centrifuged during one minute, wrapped with polyvinyl chloride, 20 mu m, in trays of expanded polystyrene and maintained in refrigerated environment, at 6 +/- 1 degrees C and 85-90% of relative humidity, during eight days. Little increasing was observed in pH and titratable acidity values and reduction in soluble solids during conservation period on all treatments. Treatment with AA did not differ from control for color and general appearance, while treatment with 2% CaCl2 at 20 degrees C maintained the best quality, with less intensity of browning, best general appearance and purchase intent and least strange odor at the end of evaluation period. UNESP FCA, Dept Hort, BR-18610307 Botucatu, SP, Brazil UNESP FCA, Dept Hort, BR-18610307 Botucatu, SP, Brazil

Conduziu-se este trabalho, com o objetivo de avaliar a influência dos sanificantes hipoclorito de sódio (NaClO) e de peróxido de hidrogênio (H2O2) em diferentes concentrações sobre a vida de prateleira de pequi (Caryocar brasilense Cambess.) submetido a dois tipos de processamento mínimo: "caroço fatiado" e "caroço inteiro", e armazenados a 6 ± 1° C e 90 a 95% UR, durante 15 dias. O experimento foi conduzido em delineamento inteiramente casualizado, disposto em um fatorial 2 x 6 x 5, ou seja, 2 tipos de processamento (caroços "fatiados" e "inteiros"), 6 tempos (0h, 3, 6, 9, 12, 15 dias) e 5 tratamentos (controle, NaClO 50 ppm, NaClO 100 ppm, H2O2 4% e H2O2 6%), com 3 repetições. A cada três dias foram realizadas as análises: vitamina C, polifenoloxidase, peroxidase e cor (CIE L*a*b*). O pequi minimamente processado apresentou decréscimo nos teores de vitamina C ao longo do armazenamento. O caroço fatiado mostrou-se com maior atividade da enzima polifenoloxidase em relação ao inteiro. A interação significativa entre o corte, o sanificante e o tempo ocorreu para a variável peroxidase, tendo sido observado para o caroço fatiado tratado com os sanificantes H2O2 4 e 6% maior atividade dessa enzima. Observou-se a redução do valor de L*, durante o armazenamento do pequi minimamente processado, independente do sanificante utilizado, ocasionado pelo escurecimento do produto. The objective of the present work was to evaluate the influence of the sanitizers sodium hypochlorite (NaClO) 50 and 100 ppm and 4% and 6%, hydrogen peroxide (H2O2) on the shelf life of fresh cut peki fruit (Caryocar brasilense Cambess.) submitted to two sorts of processing: "sliced stone" and whole stone", stored at 6 ± 1° C and 90 to 95% of RH for 15 days. The analyses were performed every three days. The experiment was conducted in a completely randomized design arranged by a 2 x 6 x 5 factorial, i.e. 2 sorts of processing ("sliced and whole stones"), 6 times (0h, 3, 6, 9, 12, 15 days) and 5 treatments (control, 50 ppm NaClO, 100 ppm NaClO, 4% H2O2 and 6% H2O2 ), with 3 replicates. Every three days, the following analyses were conducted: vitamin C, polyphenoloxidase, peroxidase and color (CIE L*a*b*). The fresh cut peki fruit showed decreases in the contents of vitamin C during storage. The sliced stones showed itself with an increased activity of the enzyme polyphenoloxidase relative the whole one. The significant interaction cutting sanitizer and time was found for peroxidase, the sliced stones and the sanitizers 4% and 6% H2O2 having promoted the highest activity of that enzyme. Reduced value L* during the storage of fresh cut peki fruit was observed, independent of the used sanitizer, suggesting browning of the product.

O objetivo deste trabalho foi avaliar a qualidade de produto minimamente processado, à base de quatro hortaliças - abóbora, cenoura, chuchu e mandioquinha-salsa, armazenado a 5 ºC por 8 dias. Observou-se que os teores de umidade, fibra, proteína, cinza e fração glicídica das quatro hortaliças não foram afetados pelo tempo de armazenamento, entretanto o teor de extrato etéreo aumentou. Durante o armazenamento, o teor de vitamina C e de acidez titulável diminuiu em todas as hortaliças. O teor de β-caroteno do chuchu não alterou, entretanto, aumentou na abóbora, na cenoura e na mandioquinha-salsa. O pH das quatro hortaliças aumentou com o armazenamento. Os teores de sólidos solúveis da cenoura e da mandioquinha-salsa aumentaram, não sendo afetados na abóbora e no chuchu. As notas de aparência do "mix" não foram inferiores a 7 (gostei moderadamente), durante o armazenamento. Os coliformes a 35 ºC presentes no "mix" aumentaram e não foi constatada a presença de coliformes a 45 ºC e Salmonella sp. em nenhum tempo avaliado. Conclui-se que a vida útil, entendida sob os aspectos nutricionais, sensoriais e microbiológicos, pode ser estabelecida em 8 dias sob refrigeração para abóbora, cenoura, chuchu e mandioquinha-salsa submetidos ao processamento mínimo. The goal of this study was to evaluate the quality of fresh-cut products made up of four vegetables: pumpkin, carrot, chayote, and arracacha (peruvian carrot) stored at 5 ºC for 8 days. It was observed that the contents of humidity, fiber, protein, ash, and glucidic fraction of the four vegetables were not affected by the time of storage; however, the content of ethereal extract increased. During storage, the content of vitamin C and titratable acidity decreased in all the vegetables. The content of β-carotene of chayote did not change, whereas the content in the pumpkin, carrot, and the peruvian carrot increased. The pH of the four vegetables increased during storage. The contents of soluble solid of the carrot and the peruvian carrot increased, but they were not affected for the pumpkin and chayote. The "mix" appearance ratings were not lower than 7 (liked moderately) during storage showing product acceptance by the panelists. The coliforms at 35 ºC present in the mix increased during storage. No coliforms at 45 ºC and Salmonella sp. in were observed in the period of time studied. It can be said that, according to microbiological, sensorial, and nutritional aspects, the shelf-life of minimally processed pumpkin, carrot, chayote, and peruvian carrot is 8 days under refrigeration.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:53:11Z No. of bitstreams: 1 S0101-20612009000200014.pdf: 634498 bytes, checksum: a4399eb0a15825e40351e4cdf3dc00df (MD5) Made available in DSpace on 2013-08-22T18:53:11Z (GMT). No. of bitstreams: 1 S0101-20612009000200014.pdf: 634498 bytes, checksum: a4399eb0a15825e40351e4cdf3dc00df (MD5) Previous issue date: 2009-06-01 Made available in DSpace on 2013-09-30T17:43:22Z (GMT). No. of bitstreams: 2 S0101-20612009000200014.pdf: 634498 bytes, checksum: a4399eb0a15825e40351e4cdf3dc00df (MD5) S0101-20612009000200014.pdf.txt: 38698 bytes, checksum: 8ed49381e1221a536ce883dbcd673fc9 (MD5) Previous issue date: 2009-06-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:50:49Z No. of bitstreams: 2 S0101-20612009000200014.pdf: 634498 bytes, checksum: a4399eb0a15825e40351e4cdf3dc00df (MD5) S0101-20612009000200014.pdf.txt: 38698 bytes, checksum: 8ed49381e1221a536ce883dbcd673fc9 (MD5) Made available in DSpace on 2014-05-20T13:50:49Z (GMT). No. of bitstreams: 2 S0101-20612009000200014.pdf: 634498 bytes, checksum: a4399eb0a15825e40351e4cdf3dc00df (MD5) S0101-20612009000200014.pdf.txt: 38698 bytes, checksum: 8ed49381e1221a536ce883dbcd673fc9 (MD5) Previous issue date: 2009-06-01 O objetivo deste trabalho foi avaliar a qualidade de couve-chinesa minimamente processada e tratada com cloreto de cálcio (CaCl2), ácido ascórbico (vitamina C), ácido etileno-diamino-tetracético (EDTA) e mantida sob refrigeração. Foram realizados os seguintes tratamentos: T1: testemunha (imersão em água contendo 50 mg L-1 clorin/5 minutos); T2: imersão em solução contendo CaCl2 a 1%/5 minutos; T3: imersão em solução contendo CaCl2 a 2%/5 minutos; T4: imersão em solução contendo vitamina C a 1%/5 minutos; T5: imersão em solução contendo Vitamina C a 2%/5 minutos; T6: imersão em solução contendo EDTA a 1%/5 minutos; e T7: imersão em solução contendo EDTA a 2%/5 minutos. Após a realização dos tratamentos a couve-chinesa foi centrifugada, embalada em bandejas de polietileno expandido, recoberta com policloreto de vinila (PVC) e armazenada em temperatura de 5 ± 1 °C e umidade relativa (UR) de 90 ± 2% por 8 dias. As análises físico-químicas, químicas e sensoriais foram realizadas de dois em dois dias. A presença de Salmonella foi verificada somente após a realização dos tratamentos. A partir dos resultados obtidos procedeu-se à análise de variância (ANAVA) e aplicou-se o teste de Tukey considerando-se um nível de significância p < 0,05. Houve influência significativa dos diferentes tratamentos nas características físico-químicas e químicas, como também nas avaliações da aparência geral e escurecimento. Não foi detectada presença de Salmonella em nenhum dos tratamentos realizados. de acordo com os resultados obtidos conclui-se que a couve-chinesa minimamente processada nas condições experimentais utilizadas só estaria apta para o consumo até o quarto dia de armazenamento. The present research aimed at evaluating the quality of minimally processed Chinese cabbage treated with calcium chloride (CaCl2), ascorbic acid (vitamin C), and ethylene-diamine-tetracetic acid (EDTA) and kept under refrigeration. Treatments were as follows: T1: control (immersion in water containing 50 mg L-1 Clorin/5 minutes); T2: immersion in 1% CaCl2 solution/5 minutes; T3: immersion in 2% aCl2 solution/5 minutes; T4: immersion in 1% vitamin C solution/5 minutes; T5: immersion in 2% vitamin C solution/5 minutes, T6: immersion in 1% EDTA solution/5 minutes; and T7: immersion in 2% EDTA solution/5 minutes. After the treatments, the Chinese cabbage was centrifuged, wrapped with polyvinyl chloride (PVC) in trays of expanded polyethylene and stored at 5 ± 1ºC and 90 ± 2% of relative humidity for 8 days. Physicochemical, chemical, and sensorial analyses were carried out on alternate days. The presence of Salmonella was verified only after treatments. Analysis of variance (ANAVA) and the Tukey's test, at 5% significance level, were also carried out. All different treatments significantly influenced the physicochemical and chemical characteristics affecting the general appearance and causing darkening. No Salmonella was detected in the treatments. The obtained results allowed concluding that Chinese cabbage minimally processed under the adopted experimental conditions would be suitable for consumption only up to the fourth day of storage. Universidade Estadual Paulista Faculdade de Ciências Agronômicas Departamento de Gestão e Tecnologia Agroindustrial Universidade Estadual Paulista Instituto de Biociências de Botucatu Departamento de Microbiologia e Imunologia Universidade Estadual Paulista Faculdade de Ciências Agronômicas Departamento de Gestão e Tecnologia Agroindustrial Universidade Estadual Paulista Instituto de Biociências de Botucatu Departamento de Microbiologia e Imunologia

Objetivou-se, neste trabalho, estudar o efeito de tratamentos com ácido ascórbico (AA), cloreto de cálcio (CC) e cloridrato de L-cisteína (LC) sobre a qualidade pós-colheita de banana 'Maçã' minimamente processada. Foram testadas as seguintes combinações: 1 (Controle); 2 (AA 1%); 3 (CC 1%); 4 (LC 0,5%); 5 (AA 1% + CC 1%); 6 (AA 1% + LC 0,5%); 7 (CC 1% + LC 0,5%); 8 (AA 1% + CC 1% + LC 0,5%). As bananas foram descascadas, fatiadas e imersas nos tratamentos, acondicionadas em bandejas, que foram envolvidas em filme de PVC 30 µm, e armazenadas a 5 ± 1ºC e 90 ± 3% UR, durante 4 dias. As avaliações ocorreram nos dias 0, 1, 2 e 4. Houve um aumento na perda de massa durante o tempo de armazenamento, menor no tratamento 8 em relação aos demais. A acidez total titulável aumentou linearmente com o tempo em todos os tratamentos. A perda de firmeza foi mais eficientemente contida nas fatias sob os tratamentos com cloreto de cálcio. A formação de uma coloração vermelho-rósea sobre as fatias tratadas com L-cisteína foi observada e evidenciada pelos maiores valores de a*. O valor L* e o índice de escurecimento também foram afetados pelo tratamento com L-cisteína, cujo decréscimo nesses parâmetros de cor foi maior nas fatias não-tratadas, ao longo do tempo. O tratamento de banana 'Maçã' minimamente processada com a combinação AA 1% + CC 1% + LC 0,5% foi eficiente para manutenção da sua qualidade pós-colheita. This work had the aim of studying the effect of treatments with ascorbic acid (AA), calcium chloride (CC) and L-cysteine hydrochloride (LC) on the postharvest quality of fresh-cut 'Apple' banana. The following combinations were tested: 1 (Control); 2 (AA 1%); 3 (CC 1%); 4 (LC 0.5%); 5 (AA 1% + CC 1%); 6 (AA 1% + LC 0.5%); 7 (CC 1% + LC 0.5%); 8 (AA 1% + CC 1% + LC 0.5%). The bananas were peeled, sliced and immersed into the treatments, conditioned on trays, which were wrapped with 30 µm PVC film, and stored at 5 ± 1ºC and 90 ± 3% RH, during 4 days. Evaluations occurred at 0, 1, 2 and 4 days. There was an increase in the mass loss during the storage period, lower in the treatment 8 in relation to the others. Total titratable acidity increased linearly throughout the time in all treatments. The loss of firmness was prevented more efficiently in the treatments with calcium chloride. A pinkish-red color formation on the slices treated with L-cysteine was observed and evidenced by the highest values of a*. The L* value and the browning index were also affected by the treatments containing L-cysteine, whose decrease in these color parameters was higher in the untreated slices throughout the time. The treatment of fresh-cut 'Apple' banana with the combination AA 1% + CC 1% + LC 0.5% was efficient for its postharvest quality maintenance.

Wild edible plants (WEP) with high antioxidant capacity, Rosa canina fruits, Quercus ballota acorns and Sanguisorba minor (young leaves and stems), were added to orange and kiwifruit juices for increase the nutritional properties. The addition of WEP to orange juice (OJ) and kiwifruit cremogenate (KC) does not affect, or it can even improve, some parameters of consumer's acceptance, although the mixtures increasing sweetness and intensifying the matrix colour without changing the tone are the best valued. The beverages minimally processed with higher TSS were the matrices fortified with Q. ballota , the same that were considered sweetest by the judges. The addition of WEP to OJ did not significantly change the levels of vitamin C (ascorbic acid plus dehydroascorbic acid). The addition of R. canina and S. minor increased the content of phenolic compounds and antioxidant capacity in both matrices (OJ and KC) in more than 30%. Beverages with a high interest for consumers and with high antioxidant properties have been obtained.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:53:02Z No. of bitstreams: 1 S0101-20612003000300020.pdf: 602676 bytes, checksum: 0f661a96a92e7344cb4daf0c161c08ca (MD5) Made available in DSpace on 2013-08-22T18:53:02Z (GMT). No. of bitstreams: 1 S0101-20612003000300020.pdf: 602676 bytes, checksum: 0f661a96a92e7344cb4daf0c161c08ca (MD5) Previous issue date: 2003-12-01 Made available in DSpace on 2013-09-30T18:00:57Z (GMT). No. of bitstreams: 2 S0101-20612003000300020.pdf: 602676 bytes, checksum: 0f661a96a92e7344cb4daf0c161c08ca (MD5) S0101-20612003000300020.pdf.txt: 24928 bytes, checksum: 2dcb056696881278a85a7422e58f3671 (MD5) Previous issue date: 2003-12-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:15:20Z No. of bitstreams: 2 S0101-20612003000300020.pdf: 602676 bytes, checksum: 0f661a96a92e7344cb4daf0c161c08ca (MD5) S0101-20612003000300020.pdf.txt: 24928 bytes, checksum: 2dcb056696881278a85a7422e58f3671 (MD5) Made available in DSpace on 2014-05-20T13:15:20Z (GMT). No. of bitstreams: 2 S0101-20612003000300020.pdf: 602676 bytes, checksum: 0f661a96a92e7344cb4daf0c161c08ca (MD5) S0101-20612003000300020.pdf.txt: 24928 bytes, checksum: 2dcb056696881278a85a7422e58f3671 (MD5) Previous issue date: 2003-12-01 Foram utilizados frutos de goiabeiras das cultivares Pedro Sato e Paluma, provenientes de pomar comercial, no estádio de maturação de vez, correspondente à coloração verde-mate e considerados ótimo para o consumo. Os frutos foram inicialmente imersos em solução de hipoclorito de sódio (150mg de cloro.L-1) por 5 minutos, para desinfecção superficial. Pessoas treinadas, utilizando proteção adequada e equipamentos desinfetados descascaram os frutos, cortaram-nos longitudinalmente ao meio e eliminaram a polpa com as sementes, em ambiente a 12°C. Após enxágüe com água clorada (20mg de cloro.L-1) foram embalados em contentores de tereftalato de polietileno (PET) com tampa. Estas unidades foram armazenadas a 3°C por 10 dias. Foram realizadas análises microbiológicas ao longo do período. Determinaram-se quimicamente os conteúdos de lignina, ácido ascórbico, acidez total titulável, sólidos solúveis totais e porcentagem de solubilização das pectinas, bem como as variáveis sensoriais de textura, sabor e preferência. A textura tornou-se mais frágil e os conteúdos de ácido ascórbico se reduziram, ao longo do período de armazenamento, nos produtos de ambas as cultivares. Durante este período houve aumento no conteúdo de lignina e manutenção dos conteúdos de sólidos solúveis totais (SST), acidez total titulável (ATT) e da relação SST/ATT. O produto da cultivar Pedro Sato apresentou menor perda de textura que o da 'Paluma', sendo considerado pelos provadores como o mais saboroso e, portanto, o mais preferido. Devido aos cuidados higiênicos tomados durante o processamento o produto apresentou baixa contagem microbiana (< 10³ UFC.g-1), em todas as avaliações efetuadas. Two cultivars of guava fruit, Pedro Sato and Paluma, were studied. They were both obtained from a commercial orchard, at the maturation stage of ready for harvest, corresponding to a dull-green coloration and considered perfect for eating. The fruits were initially immersed in a solution of sodium hypochlorite (150mg.L-1 chlorine) for 5 min, for superficial disinfection. Trained personnel, using adequate protection and disinfected equipment, peeled the fruits, cut them longitudinally down the middle and removed the pulp with the seeds, at a temperature of 12°C. After rinsing with chlorinated water (20mg.L-1 chlorine) the fruit halves were packaged in polyethylene terephthalate containers. These units were stored at 3°C for 10 days. Microbiological analyses were performed throughout the study. Chemical analyses of the products were carried out to determine the contents of lignin, ascorbic acid, total titratable acidity, total soluble solids and the percentage of solublized pectin, in addition to testing for the sensory variables of texture, flavor and preference. For both cultivars the texture became more fragile and the ascorbic acid content reduced during the storage period. During this period there was an increase in lignin content and no change in total soluble solids (TSS) content, total titratable acidity (TTA) and the TSS/TTA ratio. The product of the Pedro Sato cultivar showed less loss of texture than that of 'Paluma,' considered by the tasters as the one with more flavor and thus being more preferred. Because of the hygiene precautions taken during the processing of the product, it showed a lower microbial contamination (< 103 CFU.g-1), in all the tests conducted. UNESP FCAV Departamento de Tecnologia UNESP FCAV Departamento de Medicina Veterinária e Preventiva e Saúde Pública UNESP FCAV Departamento de Tecnologia UNESP FCAV Departamento de Medicina Veterinária e Preventiva e Saúde Pública

tThe effect of pH, phenolic substrates, and food additives on polyphenoloxidase (PPO) activity and ontissue browning was studied in fresh-cut ‘Rocha’ pear. Substrates 4-methylcatechol, caffeic acid, (+)-catechin hydrate, catechol, chlorogenic acid, dopamine hydrochloride, and pyrogallol, were preparedin citric acid-phosphate buffer at pHs ranging from 3.0 to 8.0. pH optima for PPO activity dependedon the phenolic substrate. Activity was optimal at pH 5.0 for catechol and 4-methylcatechol; pH 6.0 forchlorogenic acid; pH 7.0 for dopamine, caffeic acid, and catechin; and pH 8.0 for pyrogallol. Discrepancieswere observed between the pH dependency of PPO activity and browning, as assessed by objective colormeasurement. Significant correlations were obtained between enzyme activity and metric-hue difference( H*) over the pH range 3.0–8.0 for four of the eight phenolics. Chlorogenic acid, the main PPO substratein ‘Rocha’ pear, induced high tissue browning but very low PPO activity at pH 3.0–4.0. Chemical inhibitionof PPO was tested using catechol as substrate, and buffer solutions containing 250 mM Ca2+in four salts(ascorbate, chloride, lactate and propionate), 57 mM ascorbic acid, 61 mM N-acetyl-l-cysteine and 3 mM4-hexylresorcinol. PPO inhibition by additives was affected by the pH of the buffer, and was more effectivewith ascorbic acid, N-acetyl-l-cysteine and calcium ascorbate. It was concluded that inferences on tissuebrowning based on PPO activity can be misleading. Measurement of tissue color is proposed as a reliablemeans to assess the antibrowning effectiveness of additives and the pH of additives for cut pear shouldbe corrected to reduce the browning potential info:eu-repo/semantics/publishedVersion

The aim of the study was to quantify and model the retention of total anthocyanins (TAR), ascorbic acid (AAR) and total vitamin C (Vit C), and the colour changes of fresh-cut strawberries after washing disinfection with peracetic acid (PAA) at different concentrations (0–100 mg L−1), times (10–120 s) and temperatures (4–40 °C). Two strawberry cultivars (Camarosa and Selva) were used. TAR (%) and AAR (%) were principally affected by PAA concentration and processing time in both cultivars. There was an approximately 90% Vit C retention at any condition in the experimental domain for Camarosa cultivar. However, in the case of Selva cultivar, total vitamin C retention and colour changes were affected by the processing variables. Fil: Van de Velde, Franco. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina Fil: Piagentini, Andrea. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina Fil: Güemes, Daniel Raul. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina Fil: Pirovani, Maria Elida. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de Los Alimentos; Argentina

The objective of this study was to investigate the influence of the level of minimal processing and modified atmosphere on the quality of 'Champagne' orange stored under refrigeration. The fruits were subjected to the following processing: a) whole fruit without flavedo; b) whole fruit without flavedo and albedo; and c) segmented into wedges and packed as follows: uncoated packaging (control); polyethylene film; PVC film; gelatin-based edible films (3%); and polyesthyrene translucent plastic container with a lid. The minimally processed oranges were stored at 5 ± 1°C for 8 days and were subjected to physicochemical and microbiological analyses every two days. Greater weight loss occurred in fruits without flavedo and segmented, uncoated, and coated with the edible gelatin film During storage, there was a slight increase in Total Soluble Solids (TSS) for the treatments with greater weight loss and reduction in acidity and ascorbic acid, regardless of the packaging type. The microbial counts did not exceed the acceptable limits in the treatments; however, higher counts were observed at the end of storage. The minimally processed fruit packed in lidded polystyrene containers and polyethylene and PVC films kept their overall fresh visual appearance with a few physicochemical and microbiological changes up to the 8th day of storage. Objetivou-se com este trabalho determinar a influência do nível de processamento mínimo e atmosfera modificada na qualidade de laranja 'Champagne' minimamente processada armazenada sob refrigeração. Laranjas submetidas aos seguintes processos: a) remoção do albedo; b) remoção do albedo e flavedo; c) segmentada em gomos, foram acondicionadas em embalagem sem revestimento (controle), com filme de polietileno, com filme de PVC, com revestimento comestível de gelatina a 3% e em pote plástico com tampa de poliestireno. O armazenamento dos frutos foi realizado a 5 ± 1 °C por oito dias, sendo submetidos a análises físico-químicas e microbiológicas a cada dois dias. A maior perda de massa ocorreu em frutos sem flavedo e segmentados, sem revestimento e com película de gelatina. À medida que avançou o período de armazenamento, observou-se ligeira elevação no teor de SST para os tratamentos com maior perda de massa e redução da acidez e ácido ascórbico, sem efeito da embalagem. As contagens microbianas não ultrapassaram os limites preconizados em nenhum tratamento, entretanto, maiores contagens foram verificadas no final do armazenamento. As frutas minimamente processadas embaladas em potes de poliestireno com tampa, filmes de polietileno e PVC mantiveram boa aparência com poucas modificações nas características físico-químicas e microbiológicas até o 8° dia de armazenamento.

The shelf-life of chilled cut orange was evaluated in terms of physical and chemical quality characteristics, microbial contamination and sensorial acceptability. After minimal processing (peeling and cutting), fresh orange was stored in air at 4 °C. Evaluations were performed at different times of storage. The respiration rate of the fresh-cut orange was also evaluated. No significant increase was noticed in relation to the whole fruit which means that this was not the factor responsible for an accelerated deterioration of the product. During the first eight days of storage the major quality parameters remain almost unchangeable, except for titratable acidity which decreased around 36% and ascorbic acid content which decreased around 22%. With respect to microbial contamination low temperature determined a considerable shelf-life (15 days). Sensory quality was the parameter which determined the shelf-life of cut orange to five days at 4 °C due to flavour changes.

The purpose of this research was to determine the shelf life of minimally processed (MP) 'Pérola' pineapples treated with ascorbic acid (AA) and citric acid (CA) based on physical, chemical, sensorial and microbiological attributes. Slices were dipped into drinking water (control) or combined solutions of AA:CA (%) (1.0:0.5 and 1.0:1.0) with sodium hypochlorite (NaClO 20 mg L-1) for 30 seconds. The samples were conditioned in polyethylene terephtalate packages and stored at 4±1 °C per 13 days. The low peroxidase activity in the slices treated with antioxidant combinations was related to low pH values observed in these samples. The treatments 1.0:0.5 and 1.0:1.0 (AA:CA, %) favored maintenance of the initial a* values and avoided the pulp browning. The ascorbic acid increased more than double on the 2nd day in the treated slices. By the 4th day the CO2 values suggested a higher respiratory activity in the slices treated with anti-browning compounds. The antioxidant treatments did not produce detectable residual flavors in the MP pineapple. Regardless of microbiological safety during the 13 days of cold storage, the control slices can be kept by 6 days, afterwards the color and dehydration become strong enough to affect the appearance. On the other hand, MP 'Pérola' pineapples treated with 1.0:0.5 (AA:CA, %) and NaClO (20 mg L-1) can be stored for 8 days at 4±1 ºC, which represents the extension of the shelf life in 2 days. After this period the overripe odor starts to develop. Procurou-se determinar a vida útil de abacaxis 'Pérola' minimamente processados (MP), tratados com ácido ascórbico (AA) e ácido cítrico (AC), com base nos atributos físicos, químicos, sensoriais e microbiológicos. As fatias foram imersas em água (controle) ou em soluções combinadas de AA:AC (%) (1,0:0,5 e 1,0:1,0) com adição de hipoclorito de sódio (NaOCl 20 mg L-1), durante 30 segundos. As amostras foram acondicionadas em embalagens de polietileno tereftalato e mantidas à temperatura de 4±1 °C durante 13 dias. A baixa atividade da peroxidase nas fatias tratadas foi relacionada aos baixos valores de pH observados nessas amostras. Os tratamentos 1,0:0,5 e 1,0:1,0 (AA:AC, %) favoreceram a manutenção dos valores iniciais de a* e evitaram o escurecimento da polpa. A concentração de ácido ascórbico aumentou mais que o dobro, no 2.° dia, nas fatias tratadas. Os valores de CO2 observados no 4.° dia sugeriram a ocorrência de maior atividade respiratória nas fatias tratadas com os compostos antioxidantes. Os tratamentos antioxidantes não produziram sabor e odor residuais no abacaxi MP. Apesar de comprovada a segurança microbiológica durante os 13 dias de armazenamento, as fatias-controle podem ser mantidas por seis dias, uma vez que o escurecimento e o aspecto desidratado prejudicam a aparência do produto após esse período. Abacaxis 'Pérola' MP tratados com 1.0:0.5 (AA:AC, %) e NaOCl (20 mg L-1) podem ser armazenados por 8 dias a 4±1 ºC, o que representa o prolongamento da vida útil em dois dias. Após esse período, o odor de sobremaduro começa a se desenvolver.

O escurecimento enzimático e o amolecimento são as principais alterações que podem afetar pêssegos minimamente processados (MP). Objetivou-se avaliar a aplicação de L-cisteína (Cis), ácido L-ascórbico (AA) e cloreto de cálcio (CC) no controle do escurecimento enzimático e da perda de firmeza de polpa de pêssegos MP, cv. 'Esmeralda'. Os frutos foram processados e, após o fatiamento, imersos nos tratamentos: (I) água (controle); (II) AA+CC; (III) Cis+CC; e, (IV) Cis+AA+CC. Em seguida, as fatias foram acondicionadas em embalagens rígidas envoltas com filme PVC de 30µm de espessura e armazenadas durante seis dias a 4±1°C e 85±3% UR. As amostras foram avaliadas quanto aos aspectos físico-químicos, enzimáticos e sensoriais a cada dois dias. O tratamento Cis+AA+CC resultou em maiores valores de L* e h°, o que indica ter sido o mais eficaz na prevenção do escurecimento. Os tratamentos com L-cisteína resultaram em menor atividade da polifenoloxidase (PPO) e o tratamento Cis+AA+CC foi o mais efetivo na contenção da atividade da peroxidase (POD), indicando que o melhor desempenho desse tratamento está associado à menor atividade de PPO e POD. A avaliação sensorial indicou que o tratamento Cis+AA+CC foi o mais eficiente, proporcionando a manutenção de características sensoriais aceitáveis aos pêssegos MP, cv. 'Esmeralda'. The enzymatic browning and firmness loss are the major changes that could affect fresh-cut peaches. The objective was to evaluate the application of L-cysteine (Cis), L-ascorbic acid (AA) and calcium chloride (CC) in the control of browning enzymatic and loss of firmness of minimally processed dried peaches, cv. 'Esmeralda'. The fruits were processed industrially and, after slicing, immersed in treatments: (I) water (control); (II) AA+CC; (III) Cis+CC and (IV) Cis+AA+CC. After, the slices were packed in packages sealed with PVC film 30µm thick and stored for six days at 4±1°C and 85±3% UR. The samples were evaluated for their physical-chemical, enzymatic and sensory aspects every two days. Treatment Cis+AA+CC resulted in higher values of L* and h°, which indicates that it was the most effective in browning prevention. Treatments with L-cysteine resulted in lower activity of polyphenoloxidase (PPO) and treatment Cis+AA+CC was the most effective in containing peroxidase (POD) activity, indicating that the best performance for such treatment is associated with lower activity of PPO and POD. The sensory evaluation indicated that the treatment Cis+AA+CC was the most efficient, providing the maintenance of the sensory characteristics acceptable for fresh-cut peaches, cv. 'Esmeralda'.

6 páginas, 1 figura, 5 tablas., The effect of minimal processing on the health-related attributes of orange fruit was investigated. Oranges were prepared as whole fruits, hand-peeled fruits and manually separated segments, packed under air atmosphere and stored at 4 °C for 12 days. The stability of main bioactive compounds (carotenoids, flavanones and vitamin C) and antioxidant activity was evaluated. The total carotenoid content showed a significant increase for the whole samples during refrigerated storage, whereas no significant changes were observed for segments or peeled samples. A similar trend was found for vitamin A. With regard to vitamin C, at the end of refrigerated storage, some losses were observed although no significant differences were found among the different processed samples. The flavanone content showed a significant increase throughout refrigerated storage as response to cold stress. In general, the antioxidant activity remained stable in relation to the initial values. Hence, the health-related characteristics of minimally processed oranges were retained during refrigerated storage., This work has been financially supported by the Spanish Ministry of Science and Innovation (AGL2006-12758-C02-01/ALI; AGL- 2008-04798/C02-01/ALI; Program Consolider-Ingenio 2010, FUNC- FOOD, CSD2007-00063) and the European Union (project STREP HighQ RTE, FP6-FOOD-023140). L. Plaza would like to thank the Spanish National Research Council (CSIC) for a JAE-Doc research contract.

The storage of minimally processed vegetables at low temperatures, in association with proper packaging, represents one of the available technological solutions to mitigate the variations that hinder the quality of final products during storage. We studied the physicochemical variations that occur straight after minimal processing, as well as those that occur during the storage of minimally processed and intact leaves of collard greens (Brassica oleracea var. acephala), stored in 50-µm thick polypropylene bags, with 810-μm diameter perforations. Leaves were stored for 15 and 9 days, at 5 and 10± 1ºC, respectively. There were losses of total chlorophyll, soluble sugars, starch, and soluble amino acids immediately after the minimal processing. The rates of degradation and/or use of chlorophyll, ascorbic acid, soluble sugars, and starch during storage were similar on minimally processed and intact leaves, independently of the storage temperature. On contrary, fresh mass loss was almost two fold larger in minimally processed leaves after nine days of storage, regardless of temperature. We also observed a transient increase in the content of soluble amino acids at the end of storage in minimally processed leaves. The increase in the storage temperature to 10°C enhanced the chemical variations both in minimally processed and intact leaves. As consequence, the rates of degradation and/or use of chlorophyll, ascorbic acid, sugars and starch mounted, and the accumulation of soluble amino acids was stimulated. We concluded that it is necessary to keep on searching for alternative packaging for minimally processed collard greens, and to associate it with storage at low temperatures, but mimicking distribution and commercialization conditions of the cold-chain. Thus, we can succeed in adequately reducing the physicochemical variations that induce quality losses in minimally processed vegetables. A conservação de hortaliças minimamente processadas em baixas temperaturas, em associação com o uso de embalagens adequadas, continua sendo uma das soluções tecnológicas utilizadas para minimizar ou retardar as mudanças que ocorrem durante a conservação. Foram estudadas as alterações físico-químicas causadas logo após o processamento mínimo e durante a conservação de folhas de couve-comum (Brassica oleracea var. acephala) inteiras e minimamente processadas, mantidas em sacos de polipropileno de 50 µm de espessura, com perfurações de 810 µm de diâmetro. As folhas foram conservadas por 15 e 9 dias, a 5 e 10± 1ºC, respectivamente. Logo após o processamento mínimo observou-se perda de clorofilas totais, açúcares solúveis, amido e aminoácidos solúveis. As taxas de degradação e/ou utilização da clorofila total, ácido ascórbico, açúcares solúveis e amido durante a conservação das folhas inteiras e minimamente processadas mantidas a 5 e/ou 10± 1ºC foram semelhantes, com exceção para perda de massa fresca e aminoácidos solúveis. As folhas minimamente processadas apresentaram perda de massa fresca quase duas vezes superior às folhas inteiras com nove dias de conservação, independentemente da temperatura. Um aumento transitório no teor de aminoácidos solúveis no final da conservação também foi observado em folhas minimamente processadas. O aumento da temperatura de conservação para 10ºC potencializou as alterações químicas tanto em folhas inteiras e minimamente processadas, resultando em elevadas taxas de degradação e/ou utilização de clorofilas, ácido ascórbico, açúcares e amido, além de estimular o acúmulo de aminoácidos solúveis. É necessária a contínua busca de embalagens alternativas àquelas existentes para couve minimamente processada, associado à conservação em baixas temperaturas, para simular as condições de distribuição e comercialização e, assim, minimizar as alterações físico-químicas que reduzem a qualidade do produto final.

In this research, Pumpkin was minimally processed and stored after modified atmosphere packaging. Washed and peeled pumpkins were cut into small pieces and put into 1500 ppm Na-metabisulphide + 1% NaCl solution. The cut pieces were divided into two groups and both of them were dip-treated with 150 ppm Na-hypochloride for 5 minutes and washed with tap water. After that when the first group was dipped into the solution containing citric acid (1.5%) for 5 minutes; the second group was dipped into the solution of L-cysteine (0.5%) for 10 minutes. Approximately 200 g samples were packed in polypropylene dishes and BOPP film packages. Packages were also separated into two groups. The first group was sealed with 80% vacuum with 80% N-2 and the second group was sealed with 80% vacuum with 70% N-2 + 10%CO2. Samples were stored at 4 +/- 2 degrees C. After 10 days storage, pumpkins were processed into traditional Turkish dessert called as "kabak tatlisi" and the chemical composition and organoleptic characteristics of both of the pumpkins and the desserts were investigated. During the storage period, ascorbic acid, total phenolics and total carotenoids content of pumpkins were decreased. More reductions occurred in blank samples, which were not treated with any chemicals and then packaged under modified atmosphere conditions. When the packages were examined according to their gas concentrations, decrease of oxygen was slow in the samples treated with L-cysteine, so this application decreased the respiration of pumpkins. When the results of sensory analysis for pumpkins and desserts were evaluated it was concluded that L-cysteine application was rejected by the panelists by 95% probability because of its unliked odor. However, this application provided preference in terms of their appearance. Because of so slight texture differences in the samples, they were not distinguished by the panelists for hardness criteria.

Pedúnculos de caju foram processados por métodos combinados. As principais mudanças verificadas nas características físico-químicas foram redução do pH, aumento no teor de sólidos solúveis e de açúcares redutores. Observaram-se, também, perdas percentuais de ácido ascórbico, em relação ao pedúnculo "in natura", de 23,3% após o branqueamento, 31,7% após o primeiro dia de osmose, 35,5% após o quinto dia de osmose, 69,0% após o tratamento térmico e 87,3% ao final de 60 dias de armazenamento à temperatura ambiente (~ 28° C).Cashew apples were processed by combined methods. Major physical and chemical changes were pH decrease, soluble solids and reducing sugars increase. Ascorbic acid loss was 23,3% after bleaching, 31,7% after one day osmosis, 35,5% after five day osmosis, 69,0% after heat treatment and 87,3% after 60 days storage at ambient temperature (~ 28° C).

13 pages, 11 figures, 7 tables., The influences of processing and storage on the quality indices and nutritional content of fresh-cut fruits were evaluated in comparison to whole fruits stored for the same duration but prepared on the day of sampling. Fresh-cut pineapples, mangoes, cantaloupes, watermelons, strawberries, and kiwifruits and whole fruits were stored for up to 9 days in air at 5 °C. The postcutting life based on visual appearance was shorter than 6 days for fresh-cut kiwifruit and shorter than 9 days for fresh-cut pineapple, cantaloupe, and strawberry. On the other hand, fresh-cut watermelon and mango pieces were still marketable after 9 days at 5 °C. Losses in vitamin C after 6 days at 5 °C were ≤5% in mango, strawberry, and watermelon pieces, 10% in pineapple pieces, 12% in kiwifruit slices, and 25% in cantaloupe cubes. No losses in carotenoids were found in kiwifruit slices and watermelon cubes, whereas losses in pineapples were the highest at 25% followed by 10−15% in cantaloupe, mango, and strawberry pieces after 6 days at 5 °C. No significant losses in total phenolics were found in any of the fresh-cut fruit products tested after 6 days at 5 °C. Light exposure promoted browning in pineapple pieces and decreased vitamin C content in kiwifruit slices. Total carotenoids contents decreased in cantaloupe cubes and kiwifruit slices, but increased in mango and watermelon cubes in response to light exposure during storage at 5 °C for up to 9 days. There was no effect of exposure to light on the content of phenolics. In general, fresh-cut fruits visually spoil before any significant nutrient loss occurs., M.I.G. thanks the Ministerio de Educación y Ciencia “Programa Salvador de Madariaga” and E.A. the Technical University of Cartagena for financial support.

10 pages, 6 figures, 1 table., The use of ozonated water as a sanitizer to extend the shelf life of fresh-cut lettuce and the effect on the antioxidant constituents (polyphenols and vitamin C) were investigated. Fresh-cut iceberg lettuce (Lactuca sativa L.) was washed at 4 °C using three different ozonated water dips [10, 20, and 10 activated by ultraviolet C (UV-C) light mg L-1 min total ozone dose], and the dips were compared with water and chlorine rinses. Treated lettuce was packaged in air or active modified atmosphere packaging (MAP) (4 kPa of O2 + 12 kPa of CO2 balanced with N2) and stored for 13 days at 4 °C. Despite its strong oxidizing activity, ozonated water did not stimulate the respiratory activity of fresh-cut lettuce. Moreover, ozonated water maintained the initial visual appearance of fresh-cut lettuce and controlled browning during storage in air. Initially, ozonated water and chlorine reduced the total mesophilic population by 1.6 and 2.1 log, respectively, when compared with water. Active MAP was effective in controlling total microbial growth, achieving 2.0 log reduction in relation to samples stored in air at the end of storage. On the other hand, active MAP caused a 2.0−3.5 reduction of coliforms on sanitized samples compared with water-washed samples. The most efficient treatments were ozone 20 and ozone 10 activated by UV-C, which were as effective as chlorine. Changes in individual phenolic compounds were independent of the washing treatments. In air, chlorogenic and isochlorogenic acid contents increased noticeably after 13 days while monocaffeoyltartaric and dicaffeoyltartaric acids remained unchanged. MAP effectively suppressed accumulation of caffeoylquinic derivatives, whereas caffeoyltartaric derivatives decreased during MAP storage to reach similar levels. The content of vitamin C (ascorbic acid and dehydroascorbic acid) decreased during storage, particularly under MAP. Ozonated water could be an alternative sanitizer to chlorine for fresh-cut lettuce due to good retention of sensorial quality and browning control with no detrimental reduction in the antioxidant constituents., We are grateful to Spanish CICYT (Comisión Interministerial de Ciencia y Tecnologia) Projects AGL2001-1269 and AGL2004-03060 for financial support. D.B. is the holder of a grant from the Ministerio de Ciencia y Tecnologia (Spain), reference BES-2002-0216.

7 pages, 6 figures, 1 table., l-Galactono-γ-lactone dehydrogenase (GLDH) activity and vitamin C content as ascorbic acid (AA) plus dehydroascorbic acid (DHA) were evaluated in five potato tuber cultivars (Agata, Altesse, Franceline, Manon, and Monalisa). The effect of fresh-cutting and subsequent refrigerated storage of Manon potato under different atmospheres (air, 20% CO2 + air, 100% N2, and vacuum packaging) on GLDH activity and vitamin C content was also determined. GLDH from the five potato tuber cultivars showed typical inhibition kinetics by high substrate concentration in the synthesis of AA from its physiological precursor l-galactonic acid-γ-lactone (GL). GLDH activity was not correlated with the corresponding vitamin C content in any potato tuber cultivar. GLDH from all the cultivars presented a major isoform with isoelectric point (IEP) 5, which changed to IEP = 4.3 after minimal processing. In addition, the GLDH-catalyzed synthesis of AA by the new isoform showed typical Michaelis kinetics, in which the enzyme became more efficient to catalyze the reaction. Whether the change in the isoform pattern was due to either post-translational modifications or de novo synthesis of a new isoenzyme remains unanswered. Fresh-cutting increased GLDH activity from 4.7-fold (vacuum packaging) to 11-fold (air) after 6 days. In addition, 100% of vitamin C content was retained in air and decreased in the rest of atmospheres after this storage period, following the sequence vacuum packaging (89%) > 100% N2 (78%) > 20% CO2 + air (63%). This tendency was correlated with the corresponding GLDH activity detected in each storage atmosphere, except in the case of 20% CO2 + air. Vacuum packaging proved to be the best storage condition, because fresh-cut potatoes did not turn brown and retained 89% of initial vitamin C content., This work has been partially supported by a grant from CICYT, Spain, project PTR 1995-0625OP. J. A. T. has a fellowship from Ministerio de Educación, Cultura y Deporte (Spain), reference AP2001-2493.

10 pages, 4 figures., The effect of cutting and storage in air (AIR), modified atmosphere packaging (MAP) and deep-freezing (DF) on the vitamin C content of potato strips was evaluated. The -ascorbic acid (AA) content of potato strips derived from five potato cultivars (‘Agria’, ‘Cara’, ‘Liseta’, ‘Monalisa’ and ‘Spunta’) previously held in long-term storage was determined. In a second experiment, new-season potato tubers of ‘Agria’ and ‘Spunta’ cvs were used. Fresh-cut potato strips were stored for 6 days at 4 °C while DF strips were evaluated up to 5 weeks upon storage at −22 °C. All fresh-cut samples stored in AIR showed an increase in AA content (16–108%) after 2–4 days at 4 °C. At the end of storage, all fresh-cut potatoes stored in AIR had AA contents at or above initial concentrations, except new-season ‘Spunta’ tubers which experienced a 26% decrease. Moreover, potato strips from new-season ‘Agria’ tubers increased in vitamin C content after 6 days by 12%. Steady state MAP conditions were reached after 2 days with concentrations of 8.2–9.8 kPa CO2 and 3.1–3.8 kPa O2 within the packages. Potato strips stored in MAP decreased in AA content by 14–34% compared to samples held in AIR. Frozen storage resulted in a reduced vitamin C content (23%) of ‘Spunta’ potato strips after 5 weeks while ‘Agria’ tubers did not show any change. A general increase over time in the respiration rate of potato strips was observed during storage at 4 °C. As a conclusion, vitamin C content of fresh-cut potatoes was retained in AIR storage after 6 days at 4 °C while it was reduced in MAP storage and frozen storage at −22 °C., The authors are grateful to Spanish CICYT, Project AGL2001-1269 for financial support. J.A. Tudela was supported by a grant from Consejo Superior de Investigaciones Científicas (CSIC).

Pedúnculos de caju foram processados por métodos combinados. As principais mudanças verificadas nas características físico-químicas foram redução do pH, aumento no teor de sólidos solúveis e de açúcares redutores. Observaram-se, também, perdas percentuais de ácido ascórbico, em relação ao pedúnculo "in natura", de 23,3% após o branqueamento, 31,7% após o primeiro dia de osmose, 35,5% após o quinto dia de osmose, 69,0% após o tratamento térmico e 87,3% ao final de 60 dias de armazenamento à temperatura ambiente (~ 28° C). Cashew apples were processed by combined methods. Major physical and chemical changes were pH decrease, soluble solids and reducing sugars increase. Ascorbic acid loss was 23,3% after bleaching, 31,7% after one day osmosis, 35,5% after five day osmosis, 69,0% after heat treatment and 87,3% after 60 days storage at ambient temperature (~ 28° C).