Grape pomace is a valuable waste product and various end-products have been obtained after treatments. Recently, these have been commercialized due to their health-promoting effects. Drying is a crucial part of these treatments. This study aimed to analyze the drying kinetics of grape pomace parts, which are seeds and skins. Two grape types were used in this study, namely Emir and Bogazkere varieties of Vitis Vinifera species. Seeds and skins of each variety were dried in a tray dryer at an air velocity of 1 m/s with four different air temperatures / 40, 50, 55 and 60&deg / C. The drying curves showed that the drying r ate increased with the air temperature. Six different drying models were selected from the literature and the best fitted model was determined by application of appropriate statistical methods. It was found that for Bogazkere seeds / Modified Two Term Model, for Bogazkere and Emir skins / Modified Page Model and for Emir skins / Logarithmic Model gave the best fit. The effective moisture diffusivities of each type were found for each temperature and were determined by two different approaches, experimental and estimation. The values and variation of Deff / L2 with temperature were calculated and were found to be increasing with temperature and that the Deff / L2 values were larger for grape skins than grape seeds. Arrhenius type equation was used in order to explain the temperature dependency of Deff / L2.

Made available in DSpace on 2016-12-08T16:44:53Z (GMT). No. of bitstreams: 1 PGPV06MA015.pdf: 457433 bytes, checksum: 191a4fc2d52fb82d0fcbb905664f1302 (MD5) Previous issue date: 2006-08-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Due to the social economical importance of the Cabernet Sauvignon in the processo f expansion of the cultivated área in the mountain region of Santa Catarina, today with more than 150 implanted hectares, and the little availability of information in relation to the maturation evolution and the characterization of the grape, the presente work took place in the headquarters of the Villa Francioni Vineyards, in the crop of 2005 with 800 pnats previously marked of a vineyard of Cabernet Sauvignon formed in 2001 grafted on Paulsen 1103. The vineyard was conducted in the system in Y type trellis and the spacing between the plants was of 1,5 m and between rows of 3,0 m. the accompaniment of maturation was made with five samplings in the dates of 28/02/05, 07/03/05, 14/03/05, 21/03/05 and 28/03/05. The treatments were the thinning of bunches at the level of 6, 9, 12, 15 bunches by plant and more the witness without thinning with +- 18 bunches, giving a forecast production of 2360, 3530, 4700, 5880, and 7060 kgha¯¹ respectively. For TSS, the 6, 9, 12, and 15 bunches had greater vakues than the treatment without thinning, and for total phenols and acidity it didn t have difference among the treatments. For the pH of the juice, starting from the 4° collection date, it was observed values above 3,7 for all the treatments, what is not desirable, indicating the possibility to anticipate the crop in one week. For berries weight, the treatment with 15 bunches had a growing lineal correlation; in the other treatments a decrease of the berries weight is observed starting from the 4° collection date, indicated by the polynomial equation of 2° degree. A similar beavior was observed for the anthocyanin contentes, where just the anthocyanin contentes, where just the treatment with 9 bunches propitiated na increase in the anthocyanin contentes starting from the 4° date. The results indicate that thecluster thinning did not presente significant difference in the anthocyanin text, soluble totals, total acidity and tanning barks in the remaining clusters / Devido à importância social e econômica do Cabernet Sauvignon no processo da expansão da área cultivada na região da Serra Catarinense, hoje com mais de 150 hectares implantados, e à pouca disponibilidade da informação com relação à evolução do maturação e da caracterização da uva realizou-se este trabalho. O experimento foi realizado na Vinícola Villa Francioni, na safra de 2005 com 800 plantas marcadas previamente de um vinhedo de cabernet - sauvignon formado em 2001 sobre um porta enxerto Paulsen 1103. O vinhedo foi conduzido no sistema no tipo trellis de Y e o espaçamento entre as plantas estavam de 1.2 m e entre fileiras de 3.0 m. O acompanhamento da maturação foi feito com cinco coletas realizadas nas datas de 28/02/05, de 07/03/05, de 14/03/05, de 21/03/05 e de 28/03/05. O experimento consiste no raleio de cachos ao nível de 6, 9, 12, 15 cachos por planta e mais a testemunha sem raleio com os grupos ±18 cachos por planta, dando uma produção aproximadamente de 2360, 3530, 4700, 5880, e 7060 kg ha-1respectivamente. Para SST, os tratamentos 6, 9, 12, e 15 cachos /planta tiveram uns valores maiores o tratamento testemunha, e para Fenóis totais e Acidez total não teve a diferença entre os tratamentos. Para o pH do mosto, os valores observados acima de 3.7 para todos os tratamentos, o que não é desejável, indicou a possibilidade para antecipar a colheita em uma semana. Para o peso das bagas, o tratamento com 15 cachos/planta teve uma correlação linear crescente; nos outros tratamentos uma diminuição do peso das bagas é observada a partir da data da 4°coleta, indicada pela equação polinomial do grau 2°. Um comportamento similar foi observado para os índices da antocianina, onde apenas o tratamento com 9 grupos propiciou um aumento nos índices da antocianinas que a partir da 4° coleta. Os resultados indicam que o raleio de cachos não apresentou diferença significativa no teor de antocianina, solúveis totais, acidez total e taninos nos cachos remanescentes

Embora os efeitos benéficos da ingestão moderada do vinho sejam bem conhecidos, a capacidade antioxidante de sucos de uva é ainda pouco estudada. O suco de uva é um alimento composto por uma importante quantidade de polifenóis e pode ser incluído entre os alimentos com potencial antioxidante. Seu estudo é muito relevante pelo amplo consumo desta bebida e a importância econômica que apresenta em nossa região. Atualmente contamos com diferentes sucos de uva no mercado, brancos, tintos e roses, orgânicos ou convencionais. O suco de uva possui vários nutrientes e compostos bioativos com atividades antioxidante, antimutagênica, anticarcinogênica e antiaterogênica, entre outras. Os polifenóis são nutrientes de grande importância no suco de uva, visto que a presença destes pode contribuir para coloração, acidez e outras características importantes do suco. Aos polifenóis, já são atribuídas várias atividades benéficas a saúde do homem. Entretanto, pouco se sabia sobre a atividade do suco, o qual é uma substância complexa. Neste sentido, este estudo buscou avaliar: 1) atividade antioxidante e antimutagênica de diferentes sucos de uva e a influência de metais presentes nestes sucos; 2) atividade antioxidante do suco de uva rose; 3) atividade neuroprotetora e hepatoprotera do suco de uva em ratos Wistar jovens; 4) atividade antioxidante sérica do suco de uva em ratos Wistar jovens; 5) atividade neuroprotetora, hepatoprotetora, antigenotóxica em ratos Wistar envelhecidos; e 6) proteção do resveratrol e da catequina frente a diferentes agentes estressores em diferentes linhagens da levedura S. cerevisiae. Alguns metais apresentaram correlações positivas com estas atividades, como o Manganês, e negativas como, por exemplo, o Enxofre. O conteúdo de minerais variou entre sucos brancos e tintos. Entretanto, entre os mais prevalentes, está o potássio. Sendo assim, as correlações apresentadas também diferenciam entre os sucos brancos e tintos. Modelos in vivo contaram com grupos de ratos Wistar (machos) que foram tratados por gavagem duas vezes ao dia durante 30 dias, tendo no total um volume de suco de uva corresponde ao seu peso. Os ratos foram divididos em três grupos: controle (recebeu salina), suco de uva convencional e suco de uva orgânico. No 30º dia os animais recebiam uma dose equivalente ao seu peso de um agente estressor (CCl4) e após cinco horas foram sacrificados. Foi possível observar que os sucos de uva estudados possuem atividade antioxidante e antimutagênica importante no modelo da levedura S. cerevisiae. No modelo in vivo (ratos Wistar) observou-se uma ação neuroprotetora, hepatoprotetora e antioxidante sérica em ratos jovens. Nos ratos mais velhos observou-se também ação antigenotóxica importante. Nestes trabalhos, observou-se importantes correlações entre as atividades benéficas e o conteúdo polifenólico, principalmente referente ao conteúdo de resveratrol e catequina, nãoflavonóide e flavonóide, respectivamente. Observando-se que o suco de uva é uma mistura complexa, foram realizados estudos envolvendo estes polifenóis a fim de analisar a influência dos mesmos isoladamente no modelo da levedura S. cerevisiae. Foi possível observar pelos resultados que ambos os polifenóis, quando em quantidades semelhantes, são antioxidantes em potencial, sem diferença estatística. Entretanto, utilizando-se linhagens proficientes e deficientes nos sistemas de defesa antioxidante, foi possível observar que os danos causados pelos agentes estressores são revertidos por ambos polifenóis pela ação principalmente da enzima catalase. Estudos adicionais com modelos específicos para determinadas doenças ou até mesmo com humanos fazem-se necessários, entretanto pode-se concluir que o suco de uva é um alimento rico em polifenóis, vitamina C, minerais e que possui uma importante atividade antioxidante tanto in vitro como in vivo. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-03-09T18:17:17Z No. of bitstreams: 1 Tese Caroline Dani.pdf: 26781741 bytes, checksum: 95432174adcbf84790c1b9c5d98a97fc (MD5) / Made available in DSpace on 2015-03-09T18:17:17Z (GMT). No. of bitstreams: 1 Tese Caroline Dani.pdf: 26781741 bytes, checksum: 95432174adcbf84790c1b9c5d98a97fc (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES. / Although the beneficial effects of the moderate intake of wine are well known, the antioxidant capacity of grape juices is still little reported. Grape juice is a food which has important amount of polyphenols, thus, it can be included among the foods with high antioxidant potential. Studies with grape juice are very relevant since this beverage is widely consumed and presents economical importance in our region. Nowadays there are several types of grape juices in the market; white, purple and rose, organic or conventional. Grape juice has many nutrients and bioactive compounds with antioxidant, antimutagenic, anticarcinogenic and antiteratogenic activities. Polyphenols are components which play important roles in grape juice, since their presence contributes to the coloring, acidity and other characteristics of the juice. Several beneficial activities to human health are attributed to polyphenols. However, studies related to juice beneficial activity, a complex substance, were scarce. This study aimed to assess: 1) antioxidant and antimutagenic activities of different grape juices and the metals influence in these activities; 2) antioxidant activity of rose grape juice; 3) neuroprotective and hepatoprotective activities of grape juice in young Wistar rats; 4) serum antioxidant activity of grape juice in young Wistar rats; 5) neuroprotective, hepatoprotective and antigenotoxic activities in old Wistar rats; and 6) protective activity of resveratrol and catechin against distinct stressor agents in different strains of S. cerevisiae yeast. Some metals like Manganese and Sulfur showed positive and negative correlations with these activities, respectively. Moreover, mineral content varied between white and purple juices. However, Potassium was the most prevalent mineral (in both juices). Thus, the correlations reported could also distinguish white from purple juices. Wistar rats (male) were used as in vivo models. They were treated by gavage twice a day, for 30 days, receiving in total a volume of grape juice corresponding to their weight. Rats were divided into three groups: control (saline), organic and conventional grape juice. On the 30th day, half of each group received a single dose of the stressor agent CCl4 equivalent to their weight. After six hours, the animals were sacrificed. Experiments with the moldel yeast S. cerevisiae demonstrated that the grape juices studied present important antioxidant and antimutagenic activities. The in vivo model (Wistar rats) showed neuroprotective, hepatoprotective and seric antioxidant actions of grape juices in young rats. In oldest rats, antigenotoxic activity was found. These studies demonstrated important correlations between beneficial activities and polyphenolic content, mainly related to resveratrol and catechin, nonflavonoid and flavonoid compounds, respectively. Since grape juice is a complex mixture of compounds, involving these polyphenols were carried out in order to analyze their isolated influence on S. cerevisiae yeast model. Our results suggest that both polyphenols when applied in similar amountm have the same antioxidant potential. However, when studying strains proficient and deficient in antioxidant defense systems, the damages from stressor agents are reverted by both polyphenols, mainly under the action of catalase enzyme. Further studies with specific models of certain diseases or even with humans are needed. Our findings demonstrated that grape juice is a food rich in polyphenols, vitamin C and minerals which plays important in vitro and in vivo antioxidant activities.

Embora os efeitos benéficos da ingestão moderada do vinho sejam bem conhecidos, a capacidade antioxidante de sucos de uva é ainda pouco estudada. O suco de uva é um alimento composto por uma importante quantidade de polifenóis e pode ser incluído entre os alimentos com potencial antioxidante. Seu estudo é muito relevante pelo amplo consumo desta bebida e a importância econômica que apresenta em nossa região. Atualmente contamos com diferentes sucos de uva no mercado, brancos, tintos e roses, orgânicos ou convencionais. O suco de uva possui vários nutrientes e compostos bioativos com atividades antioxidante, antimutagênica, anticarcinogênica e antiaterogênica, entre outras. Os polifenóis são nutrientes de grande importância no suco de uva, visto que a presença destes pode contribuir para coloração, acidez e outras características importantes do suco. Aos polifenóis, já são atribuídas várias atividades benéficas a saúde do homem. Entretanto, pouco se sabia sobre a atividade do suco, o qual é uma substância complexa. Neste sentido, este estudo buscou avaliar: 1) atividade antioxidante e antimutagênica de diferentes sucos de uva e a influência de metais presentes nestes sucos; 2) atividade antioxidante do suco de uva rose; 3) atividade neuroprotetora e hepatoprotera do suco de uva em ratos Wistar jovens; 4) atividade antioxidante sérica do suco de uva em ratos Wistar jovens; 5) atividade neuroprotetora, hepatoprotetora, antigenotóxica em ratos Wistar envelhecidos; e 6) proteção do resveratrol e da catequina frente a diferentes agentes estressores em diferentes linhagens da levedura S. cerevisiae. Alguns metais apresentaram correlações positivas com estas atividades, como o Manganês, e negativas como, por exemplo, o Enxofre. O conteúdo de minerais variou entre sucos brancos e tintos. Entretanto, entre os mais prevalentes, está o potássio. Sendo assim, as correlações apresentadas também diferenciam entre os sucos brancos e tintos. Modelos in vivo contaram com grupos de ratos Wistar (machos) que foram tratados por gavagem duas vezes ao dia durante 30 dias, tendo no total um volume de suco de uva corresponde ao seu peso. Os ratos foram divididos em três grupos: controle (recebeu salina), suco de uva convencional e suco de uva orgânico. No 30º dia os animais recebiam uma dose equivalente ao seu peso de um agente estressor (CCl4) e após cinco horas foram sacrificados. Foi possível observar que os sucos de uva estudados possuem atividade antioxidante e antimutagênica importante no modelo da levedura S. cerevisiae. No modelo in vivo (ratos Wistar) observou-se uma ação neuroprotetora, hepatoprotetora e antioxidante sérica em ratos jovens. Nos ratos mais velhos observou-se também ação antigenotóxica importante. Nestes trabalhos, observou-se importantes correlações entre as atividades benéficas e o conteúdo polifenólico, principalmente referente ao conteúdo de resveratrol e catequina, nãoflavonóide e flavonóide, respectivamente. Observando-se que o suco de uva é uma mistura complexa, foram realizados estudos envolvendo estes polifenóis a fim de analisar a influência dos mesmos isoladamente no modelo da levedura S. cerevisiae. Foi possível observar pelos resultados que ambos os polifenóis, quando em quantidades semelhantes, são antioxidantes em potencial, sem diferença estatística. Entretanto, utilizando-se linhagens proficientes e deficientes nos sistemas de defesa antioxidante, foi possível observar que os danos causados pelos agentes estressores são revertidos por ambos polifenóis pela ação principalmente da enzima catalase. Estudos adicionais com modelos específicos para determinadas doenças ou até mesmo com humanos fazem-se necessários, entretanto pode-se concluir que o suco de uva é um alimento rico em polifenóis, vitamina C, minerais e que possui uma importante atividade antioxidante tanto in vitro como in vivo. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES. / Although the beneficial effects of the moderate intake of wine are well known, the antioxidant capacity of grape juices is still little reported. Grape juice is a food which has important amount of polyphenols, thus, it can be included among the foods with high antioxidant potential. Studies with grape juice are very relevant since this beverage is widely consumed and presents economical importance in our region. Nowadays there are several types of grape juices in the market; white, purple and rose, organic or conventional. Grape juice has many nutrients and bioactive compounds with antioxidant, antimutagenic, anticarcinogenic and antiteratogenic activities. Polyphenols are components which play important roles in grape juice, since their presence contributes to the coloring, acidity and other characteristics of the juice. Several beneficial activities to human health are attributed to polyphenols. However, studies related to juice beneficial activity, a complex substance, were scarce. This study aimed to assess: 1) antioxidant and antimutagenic activities of different grape juices and the metals influence in these activities; 2) antioxidant activity of rose grape juice; 3) neuroprotective and hepatoprotective activities of grape juice in young Wistar rats; 4) serum antioxidant activity of grape juice in young Wistar rats; 5) neuroprotective, hepatoprotective and antigenotoxic activities in old Wistar rats; and 6) protective activity of resveratrol and catechin against distinct stressor agents in different strains of S. cerevisiae yeast. Some metals like Manganese and Sulfur showed positive and negative correlations with these activities, respectively. Moreover, mineral content varied between white and purple juices. However, Potassium was the most prevalent mineral (in both juices). Thus, the correlations reported could also distinguish white from purple juices. Wistar rats (male) were used as in vivo models. They were treated by gavage twice a day, for 30 days, receiving in total a volume of grape juice corresponding to their weight. Rats were divided into three groups: control (saline), organic and conventional grape juice. On the 30th day, half of each group received a single dose of the stressor agent CCl4 equivalent to their weight. After six hours, the animals were sacrificed. Experiments with the moldel yeast S. cerevisiae demonstrated that the grape juices studied present important antioxidant and antimutagenic activities. The in vivo model (Wistar rats) showed neuroprotective, hepatoprotective and seric antioxidant actions of grape juices in young rats. In oldest rats, antigenotoxic activity was found. These studies demonstrated important correlations between beneficial activities and polyphenolic content, mainly related to resveratrol and catechin, nonflavonoid and flavonoid compounds, respectively. Since grape juice is a complex mixture of compounds, involving these polyphenols were carried out in order to analyze their isolated influence on S. cerevisiae yeast model. Our results suggest that both polyphenols when applied in similar amountm have the same antioxidant potential. However, when studying strains proficient and deficient in antioxidant defense systems, the damages from stressor agents are reverted by both polyphenols, mainly under the action of catalase enzyme. Further studies with specific models of certain diseases or even with humans are needed. Our findings demonstrated that grape juice is a food rich in polyphenols, vitamin C and minerals which plays important in vitro and in vivo antioxidant activities.

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-01-11T11:34:22Z No. of bitstreams: 2 Tese - Mábio João Santana - 2017.pdf: 5831508 bytes, checksum: e1e52470fde694c18c0e418a051f7f3e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-01-11T11:34:45Z (GMT) No. of bitstreams: 2 Tese - Mábio João Santana - 2017.pdf: 5831508 bytes, checksum: e1e52470fde694c18c0e418a051f7f3e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-01-11T11:34:45Z (GMT). No. of bitstreams: 2 Tese - Mábio João Santana - 2017.pdf: 5831508 bytes, checksum: e1e52470fde694c18c0e418a051f7f3e (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-12-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The present study aims to trace the chemical profile and to quantify carbohydrates glucose, fructose and sucrose in both integral and nectar grape juices through 1H NMR experiments using two quantification methods – external and electronic (ERETIC) reference. Both methods were efficient and in one single experiment were able to quantify simultaneously the three carbohydrates, to characterize the main constituents, as well as allowed us to know the level of fruit maturity and ethanol content in the juices. We have also observed a high content of fructose in the integral grape juice, which can mean a healthy risk since at elevated concentrations this monosaccharide could lead to insulin resistance syndrome and hyperuricemia. Furthermore, an alarming fact is that among the 24 brands of nectar grape juices analyzed, only four brands fulfilled the established limits of sucrose content and two of them were present with a sucrose content higher than 10 times that allowed by current legislation, being such nonconformity undetectable by methods actually used. The statistical analyzes demonstrate the influence of relaxation time on the trend of grouping the data, associating the same sample in completely different groups when not observed the time of five times the relaxation time (T1). Other observation was also allowed us to observe the distinct grouping between the nectar samples, which were qualified as sweetened with apple juice, and this information was not included on the label at the time of analysis, even though it was established by legislation. / O presente estudo tem como objetivo avaliar o perfil químico e quantificar carboidratos de glicose, frutose e sacarose em sucos de uvas integrais e de néctar através de experimentos de RMN de 1H usando dois métodos de quantificação - referência externa e eletrônica (ERETIC). Ambos os métodos foram eficientes e em um único experimento foram capazes de quantificar simultaneamente os três carboidratos, para caracterizar os constituintes principais, além de nos permitir conhecer o nível de maturação da fruta e o teor de etanol nos sucos. Também observamos um alto teor de frutose no suco de uva integral, o que pode significar um risco à saúde, pois em concentrações elevadas este monossacarídeo pode levar a síndrome de resistência à insulina e hiperuricemia. Além disso, um fato alarmante é que, entre as 24 marcas de sucos de uva de néctar analisados, apenas quatro marcas preencheram os limites estabelecidos de teor de sacarose e dois deles apresentaram um teor de sacarose superior a 10 vezes permitido pela legislação atual, sendo essa não-conformidade indetectável por métodos oficialmente utilizados. As análises estatísticas demonstram a influência do tempo de relaxação na tendência de agrupamento dos dados, associando a mesma amostra em grupos completamente diferentes quando não observados o tempo de cinco vezes o tempo de relaxamento (T1). Outras observações também nos permitiram observar o agrupamento distinto entre as amostras de néctar, qualificadas como adoçadas com suco de maçã, e essa informação não foi incluída no rótulo no momento da análise, embora tenha sido estabelecida por legislação.

Os produtos com umidade reduzida têm-se evidenciados como proposta alternativa para disponibilizar produtos de origem vegetal caracterizados pelo alto teor de umidade e vida útil curta, proporcionando, assim, um produto diferenciado, estável, com maior tempo de vida útil, além de possibilitar diversificação no consumo e aplicações. Este trabalho teve como objetivo a desidratação de minitomates inteiros do híbrido Sweet Grape, pelo processo de secagem convectiva adiabática e as interferências do pré-tratamento osmótico e adição de antioxidante, além da comparação do produto desidratado e liofilizado. O tratamento osmótico consistiu de cinco combinações de soluções osmóticas compostas por açúcar invertido, sacarose e cloreto de sódio. A desidratação adiabática foi caracterizada por duplo estágio a 80°C/ 2h em seguida a diferentes temperaturas: 50, 60, 70 e 80°C, até atingir umidade do produto de aproximadamente 30%. Foram aplicados antioxidantes e acidulante (ácido ascórbico, metabissulfito de sódio e ácido cítrico), no intuito de minimizar as alterações durante a desidratação. Em seguida, foi realizado um comparativo entre minitomates desidratados e liofilizados, acondicionados em embalagem laminada e mantidos a 5°C por 120 dias. O tratamento osmótico composto por açúcar invertido (60°Brix), sacarose (15%) e NaCl (5%) a 25°C por 50 min foi o processo mais eficaz, que apresentou menor incorporação de sólidos, maior perda de massa e menor atividade de água, associado à aplicação de 750mg.L-1 de ácido ascórbico, 50mg.L-1 de metabissulfito de sódio e 3g.L-1 de ácido cítrico. Os minitomates desidratados em duplo estágio a 80°C/2h e 70°C/11h apresentaram melhor aceitação quando comparados aos liofilizados, visto que a liofilização promoveu redução acentuada da cor e umidade, tornando o produto mais rígido. As características dos produtos desidratados e liofilizados foram mantidas estáveis por um período de 90 dias, aproximadamente, e o tratamento osmótico promoveu maior estabilidade aos produtos durante o armazenamento. / Products with low humidity have been considered an alternative for vegetable products characterized by high humidity content and short shelf life. Thus low-humidity products provide stable with longer shelf life products, enabling diversity for consumption and applications. This study investigated dehydration of whole cherry tomatoes of the Sweet Grape variety by the process of adiabatic convective drying and interference of osmotic pretreatment and antioxidant addition, comparing to dehydrated and lyophilized tomatoes. The treatment consisted of five combinations of osmotic solutions composed by inverted sugar, saccharose and sodium chloride. Adiabatic dehydration was characterized by double stage at 80°C/2 h followed by different temperatures: 50, 60, 70 and 80°C until the product reached moisture of 30%. Antioxidants and acidulants were applied (ascorbic acid, sodium metabisulphite and citric acid) to minimize changes during dehydration. Afterward, we compared dehydrated and lyophilized cherry tomatoes, packed in laminated packaging and kept at 5°C for 120 days. The osmotic treatment with inverted sugar (60° Brix), sucrose (15%) and sodium chloride (5%) at 25°C for 50 min was the most effective process. This process showed lower incorporation of solids, greater weight loss and lower water activity, associated with the application 750 mg.L-1 of ascorbic acid, 50 mg.L-1 of sodium metabisulphite and 3 g.L-1 of citric acid. The cherry tomatoes dehydrated in a double stage at 80°C/2 h and 70°C/11 h showed better acceptance when compared to lyophilized ones as freeze-drying caused greater color and moisture reduction, making the product more rigid. Characteristics of dehydrated and lyophilized products were kept stable for roughly 90 days and the osmotic treatment on the products promoted greater stability during storage.

Thesis (M.Sc. (Agricultural Economics)) -- University of Limpopo, 2020 / Table grape production plays an important role in the economy of many countries in Africa. It serves as a source of income for people who are engaged in its production and being one of the fields that is labour-intensive, thereby providing employment for many people. The aim of this study was to analyse economic efficiency of table grape production in Waterberg and Sekhukhune districts of Limpopo Province, South Africa. The study used primary data collected from semi-structured questionnaires. A sampling technique called snowball, was used in the study as this method assisted in getting those farmers that were not easily accessible. The analytical tools employed to analyse data included descriptive statistics and Stochastic Frontier Model. Findings from the study revealed that the average age of table grape farmers was 47 years. On average, household size for table grape farmers was found to be 5 members. Also, findings revealed that table grape farmers on average had a farming experience of 16 years. Average household income was found to be R47 600, 00. Furthermore, the study revealed that the average years of schooling for the table grape farmers was 15 years and only 67% of these farmers have acquired a tertiary educational level, while 33% have acquired secondary educational level. In terms of efficiency, farming experience (P<0,00), educational level (P<0,05) household size (P<0,10) and age of farmer (P<0,10) were associated with increased efficiency as they were found to be significant at 1%, 5% and 10% confidence level. The findings also revealed that quantity of grapes produced was positively influenced by Farm size (P<0,00), labour (P<0,00), pesticides used (P<0,05) , extension services (P<0,05) and fertilisers (P<0,05). Technical efficiency among farmers was found to range from 0.8 to 1, with a mean of 0.89, thus this indicated possibility of improvement in production. However, the allocative efficiency was found to range from 0.47 to 1, with a mean of 0.68, this clearly indicated that some farmers were finding it difficult to allocate their resources efficiently. On the other hand, it was found that economic efficiency ranged from 0.56 to 1, with a mean of 0.73, this indicated that most of the farmers were economically efficient. Meanwhile, some of the constraints faced by the table grape farmers included high electricity bills and labour costs, as such the introduction of prepaid electricity in the farms could reduce the strain they go through. Based on the findings from the study, it was recommended that, since the production of grapes is a male-dominated enterprise, women and youth should also participate. Participation could be encouraged through provision of learnership skills on the farms.

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Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Grape quality is important for the producer, exporter and the consumer. Consumers judge table grapes according to their size, colour, taste and shelf life. The consumer’s prerequisites will influence the producer. Therefore, it is essential to know how the table grape berry develops so that it can be manipulated, favouring the postharvest quality and shelf life. This study was performed on Prime and Crimson Seedless, both grafted onto Ramsey, in the Paarl district of South Africa. The aim of this study was to describe and quantify table grape berry development and compositional changes taking place throughout growth and ripening. The effect of sugar:acid ratio on postharvest shelf life was also evaluated. To evaluate whether berry size influenced the measured development parameters, three berry sizes were induced for both cultivars by using plant bioregulators such as gibberellic acid (GA3) and forchlorfenuron – synthetic cytokinin (CPPU) or girdling. The following sizes were obtained for Prime: (i) small berries (<20 mm) with no treatment, which acted as the control; (ii) medium berries (20-24 mm) obtained by 15 ppm GA3 application at 8 mm berry size; (iii) large berries (>24 mm) obtained by combination of 15 ppm GA3 and 1 ppm CPPU application at 8 mm berry size. Crimson Seedless berry sizes were as follows: (i) small berries (<18 mm) with no treatment, which acted as the control; (ii) medium berries (18-22 mm) treated with 10 ppm GA3 at 7 mm berry size; (iii) large berries (>22 mm) treated with 10 ppm GA3 and vines were girdled at 7 mm berry size. To evaluate the effect of sugar:acid ratio on postharvest shelf life, grapes were stored for five weeks at -0.5 ˚C and another week at 7.5˚C. The bunches were evaluated for loose berries, browning, soft tissue breakdown, decay and berry split. The following components were analysed for both cultivars to determine changes in berry composition throughout the season: berry fresh weight, total soluble solids (TSS), glucose, fructose, titratable acidity (TA), tartaric acid, malic acid, abscisic acid (ABA) and total phenols. Total and individual anthocyanins were analysed for Crimson Seedless. Differences were obtained for the three berry sizes for both cultivars. Véraison, representing the start of ripening, started at the same time in successive seasons: 21 days after pea size berry (5 mm berry diameter) for Prime and 28 days after pea size berry (5 mm berry diameter) for Crimson Seedless. A lag stage was not observed, at seven day sampling intervals, for either of the cultivars. Components such as TSS, glucose, fructose and TA content per berry were influenced by berry size in either one or in both seasons for both cultivars. Significant changes in component concentration were detected at the start of, or around véraison. Sugar concentrations (TSS) already started to increase for both cultivars before the start of véraison. At véraison, concentrations of glucose, fructose and ABA increased while concentrations of TA, tartaric acid, malic acid and total phenols decreased. Total anthocyanins in Crimson Seedless started to increase one week after véraison commenced. The main anthocyanin found in Crimson Seedless was peonidin-3-glucoside. During ripening a 1:1 glucose:fructose ratio was detected in both cultivars. Prime tartaric:malic acid ratio was lower than Crimson Seedless tartaric:malic acid ratio in both seasons. Tartaric acid was the main organic acid found in Prime, while malic acid was the main organic acid found in Crimson Seedless. No significant differences were found in the postharvest defects between the different berry sizes. However, tendencies for differences were observed which led to the assumption that medium size berries were more prone to loose berries in both cultivars. Large berries showed a higher percentage berry split for both cultivars. Crimson Seedless second harvest date took place 24 hours after rainfall which could have very likely led to the higher percentages berry defects compared to the first season. Greater berry decay was found with later harvest dates for both cultivars. No significant differences were found for the TSS:TA ratio between the three berry sizes for both cultivars. Postharvest defects were therefore found not only to be influenced by TSS:TA ratio but rather by harvest date and packing procedures. Environmental conditions prior to harvest also had an impact on postharvest shelf life. / AFRIKAANSE OPSOMMING: Druif kwaliteit is belangrik vir die produsent, uitvoerder en verbruiker. Tafeldruiwe word gekeur deur die verbruiker volgens grootte, kleur, smaak en raklewe. Die verbruiker se voorkeure sal dus die produsent beïnvloed. Daarom is dit belangrik om te weet hoe tafeldruiwe ontwikkel ten einde korrelsamestelling te manipuleer om na-oes kwaliteit en raklewe te kan bevoordeel. Hierdie studie is uitgevoer op Prime en Crimson Seedless, beide geënt op Ramsey, in die Paarl distrik van Suid Afrika. Die doel van die studie is om vas te stel hoe korrelsamestelling gedurende groei en rypwording verander. Die effek van suiker:suurverhouding op na-oes raklewe is ook geëvalueer. Om te kan meet of korrel grootte die gemete parameter beïnvloed is drie korrelgroottes verkry vir albei kultivars deur die gebruik van plant bioreguleerders, te wete gibbereliensuur (GA3) en sintetiese sitokiniene (CPPU), of ringelering. Die volgende korrelgroottes is verkry vir Prime: (i) klein korrels (<20 mm) d.m.v. geen behandeling, geklassifiseerd as kontrole; (ii) medium korrels (20-24 mm) d.m.v. ‘n 15 dpm GA3 behandeling by 8 mm korrelgrootte; (iii) groot korrels (>24 mm) d.m.v. ‘n kombinasie van 15 dpm GA3 en 1 dpm CPPU by 8 mm korrelgrootte. Crimson Seedless korrelgroottes was soos volg: (i) klein korrels (<18 mm) d.m.v. geen behandeling, wat as kontrole gedien het; (ii) medium korrels (18-22 mm) d.m.v. ‘n 10 dpm GA3 behandeling by 7 mm korrelgrootte; (iii) groot korrels (>22 mm) d.m.v. ‘n 10 dpm GA3 behandeling en gelyktydige ringelering by 7 mm korrelgrootte. Om die effek van suiker:suur verhouding op na-oes houvermoë te kon evalueer was druiwe gestoor vir vyf weke by -0.5˚C en ‘n verdere week by 7˚C. Die trosse is geëvalueer vir loskorrels, verbruining, sagte weefsel afbreek, verval en korrelbars. Die volgende komponente is geanaliseer vir albei kultivars om veranderinge in korrelsamestelling gedurende die seisoen te bepaal: vars korrelgewig, totale oplosbare vaste stowwe (suikerinhoud), glukose, fruktose, titreerbare sure, wynsteensuur, appelsuur, absisiensuur en totale fenole. Die totale en individuele antosianiene is ook vir Crimson Seedless gemeet. Beduidende verskille tussen die drie korrelgroottes vir albei kultivars is verkry. Deurslaan, naamlik die begin van rypwording, het op dieselfde dag in opeenvolgende seisoene plaasgevind: 21 dae na ertjiekorrel grootte (5 mm korrel deursnee) vir Prime en 28 dae na ertjiekorrel grootte (5 mm korrel deursnee) vir Crimson Seedless. In teenstelling met die tipiese korrel ontwikkelingspatroon is ‘n rusfase nie waargeneem by beide kultivars nie. Komponente soos suikerinhoud, glukose, fruktose en titreerbare suur inhoud per korrel is deur korrelgrootte beïnvloed in een of albei seisoene vir beide kultivars. Suiker konsentrasie van albei kultivars het reeds voor deurslaan begin toeneem. By deurslaan het die konsentrasies van glukose, fruktose en absisiensuur inhoud toegeneem, terwyl die konsentraies van titreerbare sure, wynsteensuur, appelsuur en totale fenole gedaal het. Totale antosianiene in Crimson Seedless het ‘n week na deurslaan begin toeneem. Die hoof antosianien in Crimson Seedless is peonidien-3-glukosied. Gedurende rypwording was daar ‘n 1:1 glukose:fruktose verhouding gevind vir beide kultivars. In terme van sure is Prime se wynsteensuur:appelsuur verhouding laer as in Crimson Seedless vir albei seisoene. Wynsteensuur is die hoof organiese suur in Prime terwyl appelsuur die hoof organiese suur in Crimson Seedless is. Geen betekenisvolle verskille vir na-oes houvermoë tussen korrelgroottes is waargeneem vir beide kultivars nie. Daar was egter tendense wat aanleiding gegee het in die aanname dat medium grootte korrels geneig is tot loskorrels in albei kultivars. Groot korrels het ‘n hoër korrelbars persentasie getoon vir beide kultivars. Crimson Seedless se tweede oes het plaasgevind 24 uur na reënval, wat aanleiding gegee het tot hoër persentasies korrelbederf. Hoër persentasie korrelbederf was ook gevind met later oesdatums. Geen beduidende verskille is gevind vir suiker:suur verhouding tussen die drie korrelgroottes vir beide kultivars nie. Dus word na-oes houvermoë nie net deur suiker:suur verhouding beïnvloed nie, maar ook deur oestyd en verpakkingsprodsedures. Omgewingsomstandighede voor oes kan ook na-oes houvermoë beïnvloed.

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