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Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars.Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study. / Libyan government

Coffee grown in the United States represents less than 1% of the world's supply, and most of it comes from the state of Hawai'i. Kona coffee, grown on the western side of the island of Hawai'i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai'i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (31.6 4.3%), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time. / Doctor of Philosophy / Coffee grown in the United States represents less than 1% of the world’s supply, and most of it comes from the state of Hawai’i. Kona coffee, grown on the western side of the island of Hawai’i, is the most recognized and the highest value Hawaiian coffee. The majority of this coffee is sun-dried after harvest and washing. Sun-dried coffee should reach 12-13% moisture within 4 to 6 days. Sun-drying will reduce both the moisture content and the water activity (aw*). (*Water activity is the measurement of water vapor pressure generated by the free or non-chemically bound water in foods and other products. Water activity (range of 0 to 1) is an important indicator for the shelf life of foods and the occurrence and growth of microorganisms). Reducing aw below 0.75, especially in the first week of drying, is important for preventing or limiting mold growth. The purpose of this study was to 1) compare drying rates of Kona coffee bean batches using aw and moisture content % measurements, 2) evaluate factors affecting the drying time of sun-dried Kona coffee, and 3) provide recommendations for post-harvest processing of sun-dried Kona coffee to optimize quality and safety. Ten farms in the Kona coffee region of Hawai’i were visited in the fall of 2017 to record data on the drying rate of coffee bean batches and to record observations on the post-harvest handling and storage of coffee beans and the environmental conditions that may affect the quality and microbial contamination of drying coffee. The coffee drying surfaces, physical enclosures, fan use, and elevation varied among farms. Daily measurements of coffee moisture level, water activity, depth of bean layer and temperature were recorded along with air temperature, relative humidity and cloud cover during drying for 30 batches. Most sun-dried batches reached 13% moisture in 6 to 10 days. Initial moisture content (27 to 36 %), and drying yard characteristics varied greatly among farms. Coffee batches reached 0.75 aw within 6 days on average, but some batches required more than 10 days. Moisture content and aw measurements were weakly correlated and water activity level increased at times during drying for some batches. Allowing airflow around drying beans and maintaining a bean layer depth of less than 5 cm appeared to improve drying rates. Drying coffee parchments within 7 days post-harvest can inhibit growth of molds that may impact quality or molds that could produce mycotoxin. Controlling the drying conditions, including raking the layered beans, and monitoring moisture content can accelerate, or improve the consistency of, batch drying time.

Insect damage in stored maize is one of the major post-harvest losses occurring in developing countries, especially in sub-Saharan Africa. To reduce economic losses, separation of infested grains from clean ones is critical and requires detection of infestation in stored grains. This study aimed at developing a rapid non-destructive detection system with three goals; - the first goal was to investigate the acoustic behavior of internally feeding S. zeamais (Coleoptera: Curculionidae) in maize. The pests were monitored for peak activity and signal amplitudes. The study was performed in the morning, afternoon and night times for three consecutive days with an ultrasonic probe attached to acoustic emission detector. The average number of peaks above threshold in the morning, afternoon and night was significantly different and were 60, 2 and 31 counts/s, respectively (P-value < 0.01). The average maximum amplitude was also different: 2.5, 1 and 1.8V for morning, afternoon and night sessions, respectively. The signal frequencies ranged between 1 and 15 kHz with a peak around 7 kHz. The second goal was to design and develop an inexpensive acoustic device for the detection of S. zeamais in the stored maize. This device included a microphone, signal conditioning circuit and a microcontroller. The third goal was to test the prototype in both clean and infested maize. The device could be manufactured for $55 or less. The device has a noise level below 0.2V in clean maize, infestation amplitude up to 1V and about 93.3% correct detection performance in infected maize. / Master of Science

Raw vegetables can sometimes be the source of outbreaks of human illness; however the potential for fresh vegetables to serve as a vehicle for antibiotic -resistant bacteria is poorly understood. Antibiotics and antibiotic-resistant bacteria have been shown to persist in manure of animals administered antibiotics, and in compost generated from this manure, where there is the potential for their transfer to produce. The purpose of this study was to determine the survival of antibiotic-resistant bacteria on raw, peeled, carrots after washing with commonly used chemical sanitizers. Multi-drug resistant E. coli O157:H7 and Pseudomonas aeruginosa were inoculated into a compost slurry of composted manure from dairy cattle, with and without prior administration of antibiotics, and used to inoculate carrot surfaces prior to the washing studies. This approach provided defined model antibiotic-resistant pathogens present within a background microbial community simulating potential carry over from manure-derived fertilizer. Carrots (n=3, 25g) were air-dried and stored at 4 °C until washing with tap water, XY-12 (sodium hypochlorite, 50 ppm free chlorine) or Tsunami 100 (peroxyacetic acid/hydrogen peroxide, 40 ppm free paracetic acid), according to manufacturer's directions. A second batch of carrots representing each inoculation x wash condition (n=3) were individually packaged for storage at 2 °C for 1,7, and 14 days, or 10 °C for 7 days and enumerated on those day intervals to recover bacteria from the surfaces of washed carrots. The resulting previously washed and stored carrots were subject to serial dilution and plated onto corresponding agar to enumerate total aerobic bacteria (R2A), aerobic bacteria tolerant or resistant to antibiotics (antibiotic-supplemented R2A), E. coli (Eosin Methylene Blue), and Pseudomonas spp. (Pseudomonas Isolation Agar). In addition, the tetA gene was quantified from the carrot samples as a measure of the effect of sanitizers and storage on an antibiotic resistance gene known to be carried by the inoculated bacteria.Inclusion of sanitizer in the wash water significantly reduced the absolute numbers of inoculated bacteria (E.coli and Pseudomonas) as well as populations of bacteria capable of growth on the R2A media containing cefotaxime (10μg/mL), sulfamethoxazole (100μg/mL), or tetracycline (3μg/mL). Comparable reductions in the inoculated P. aeruginosa resistant to tetracycline (PIA T, 4μg/mL), bacteria resistant to cefotaxime (10μg/mL) and tetracycline (3μg/mL) occurred after washing with XY-12 or Tsunami 100. The sanitizer effectiveness may be bacterial dependent, as evident by larger absolute reductions of the inoculated E. coli (EMB) and bacteria grown on sulfamethoxazole (100μg/mL)-amended plates after washing with Tsunami 100 compared to washing with tap water or XY-12. Re-growth of both the inoculated and native compost-associated bacteria was inhibited by storage at 2 °C, as there were no significant differences in the log CFU/g values on the various media (total aerobic bacteria, bacteria on antibiotic-amended plates, E. coli inoculum, P. aeruginosa inoculum) during the 14-day storage period. However, temperature abuse at 10 °C resulted in significant re-growth of native Pseudomonas, compared to storage at 2 °C. A sanitizer-associated interaction between re-growth and temperature was also observed for bacteria resistant to clindamycin (25μg/mL) and cefotaxime (10μg/mL), with substantial re-growth occurring only on carrots washed with Tsunami 100. There was no significant re-growth of the inoculated E. coli O157:H7 at either temperature. Results indicate that some bacterial populations are reduced by post-harvest washes and that temperature abuse of fresh produce may result in increases in antibiotic-resistant bacterial populations. / Master of Science in Life Sciences / Fresh vegetables are frequently washed to remove soil and pests before shipment to suppliers, with the goal of creating a ready-to-eat- product for consumers. The inclusion of a chemical sanitizer in the wash water has the benefit of killing or reducing the number of bacteria in the wash water. Chemical sanitizers also have the potential to reduce spoilage bacteria and human pathogenic bacteria on the vegetable and prevent cross-contamination from one vegetable to another. While the intention of sanitizers is to reduce bacterial numbers in wash water, there can be added benefit of also reducing bacterial numbers on vegetable surfaces. Given the rising problem of antibiotic resistance, in this study we sought to determine the effectiveness of two commonly used wash water sanitizers for reducing antibiotic-resistant bacterial pathogens and other antibiotic-resistant bacteria on carrots. It was not possible to completely eliminate all bacteria on the carrots by washing, a frequent misconception. However, washing in water that included a food-grade sanitizer, Tsunami 100 (peroxyacetic acid/hydrogen peroxide) or XY-12 (sodium hypochlorite), numbers of <i>E.coli</i> and <i>Pseudomonas</i> that had been pre-inoculated on the carrots were reduced. Despite the reduction in numbers after washing, the surviving bacteria on the carrot surfaces grew significantly when stored improperly at warm temperatures (10°C instead of 2 °C). Bacteria that could grow in the presence of antibiotics were reduced by the sanitizer wash and did not re-grow when stored at 2qC. The use of food-grade sanitizers does reduce the numbers of some bacteria on carrots, but it is equally important that consumers store produce at chilled temperatures to prevent re-growth of potentially harmful bacteria.

Orientador: Benedito Carlos Benedetti / Texto em português e Inglês / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-23T16:23:18Z (GMT). No. of bitstreams: 1 Teles_CesarSimas_D.pdf: 1939088 bytes, checksum: 585b37a053cde7606fc6da4a9aa803dc (MD5) Previous issue date: 2013 / Resumo: Botrytis cinerea Pers, causador da doença conhecida como mofo cinzento, é o principal problema para a conservação pós-colheita de uvas de mesa. A utilização do dióxido de enxofre (SO2) é a prática pós-colheita mais comum para o controle desta doença. Pesquisas buscam alternativas a este produto devido às reações que causa em pessoas alérgicas, danos que pode causar nos frutos e às restrições ao seu uso em sistemas de produção orgânico. Foram avaliados os efeitos da aplicação de uma atmosfera de 40% de CO2 por 24 ou 48 horas (pré-armazenagem) combinado com armazenagem em atmosfera controlada (AC) (12% O2 + 12% CO2) no controle de B. cinerea, e nos atributos de qualidade de uvas 'Flame Seedless' e 'Crimson Seedless'. Também foram avaliados, em uvas 'Crimson Seedless', e os efeitos da associação deste tratamentos com aplicações pré-colheita de cloreto de cálcio (CaCl2) ou dióxido de cloro (ClO2). Os tratamentos foram aplicados em uvas orgânicas infectadas de três formas: infectadas naturalmente, superficialmente inoculadas com conídios e inoculadas com uma baga coberta de micélio. Uvas 'Flame Seedless', naturalmente infectadas, tratadas com 40% de CO2 por 48 horas + AC apresentaram redução da podridão pós-colheita, de 22% para 0,6%, após 4 semanas, e de 100% para 7,4%, após 7 semanas. O pré-armazenamento em 40% de CO2 sozinho também limitou a incidência de mofo cinzento em frutos infectados naturalmente e em uvas inoculadas artificialmente, porém foi menos eficaz do que quando seguido pelo armazenamento em AC. A aplicação de CaCl2 ou ClO2 em pré-colheita reduziu a incidência do mofo cinzento em uvas 'Crimson Seedless' inoculadas com uma solução de conídios, porém não houve controle quando os cachos de uva foram inoculados com micélio. A aplicação de CaCl2 e ClO2 reduziram o mofo cinzento de 45% para 23,2% e 15.6%, respectivamente, em cachos inoculados com conídios e avaliados após 6 semanas armazenadas 0oC. O pré-tratamento com 40% CO2 + CA não afetou as características físico-químicas e sensoriais de uvas 'Crimson Seedless' ou 'Flame Seedless'. Em experimentos in vitro os tratamentos com 40% CO2 por 24 ou 48 h limitaram o crescimento micelial até 72 horas após o tratamento. A germinação dos conídios de B. cinerea foi retardada por 12h. Os resultados mostram que o pré-tratamento com 40% CO2 + CA possui grande potencial para ser adotado como prática comercial para conservação de uvas orgânicas / Abstract: Gray mold, caused by Botrytis cinerea Pers, is the main postharvest decay of table grapes. The use of sulfur dioxide (SO2) is the common post-harvest practice for its control. Several researchers are looking for alternative methods of control, because SO2 can cause allergic reactions, damage fruits and also it cannot be applied in organic production system. In this thesis, it was evaluated the effects of applying an atmosphere of 40% CO2 for 24 or 48 hours (pre-storage) combined with controlled atmosphere storage (CA = 12% O2 + 12% CO2) in the control of B. cinerea, and the effects in the quality and sensory attributes of 'Flame Seedless' and 'Crimson Seedless' table grapes. In addition, it was evaluated the efficacy of CaCl2 or ClO2 application in pre-harvest alone or in combination with pre-storage of 40% CO2 for 24 h + CA, to control gray mold on 'Crimson Seedless' table grapes, and the determination of the impact of these treatments on fruit quality. The treatments were applied in certified organic table grapes naturally infected, surface inoculated and nesting inoculated (inoculated with an infected berry). After 4 weeks of storage, the pre-storage in 40% CO2 for 48 hours + CA reduced postharvest rot from 22% to 0.6%, and after 7 weeks, the decay was reduced from 100% to 7.4% in 'Flame Seedless' naturally infected. The pre-storage in 40% CO2 alone also reduced the incidence of gray mold in fruits naturally infected and in artificially inoculated, but it was less effective than combined treatment. The application of CaCl2 or ClO2 pre-harvest reduced the incidence of gray mold on grapes 'Crimson Seedless' inoculated with a spore solution, but there was no control when fruits were nesting inoculated. After 6 weeks at 0oC, the application of CaCl2, and the ClO2 in fruits surface inoculated, reduced the gray mold from 45% to 23.2% and 15.6%, respectively. The pretreatment with 40% CO2 + CA did not affect quality and nor sensory attributes for both varieties tested. In vitro experiments, the treatment with 40% CO2 for 24 or 48 h limited mycelial growth for at least 72 hours after treatment. Conidial germination of B. cinerea was delayed for 12 hours. Our results showed the potential that pre-treatment with 40% CO2 associated with CA has to be adopted in commercial practice for preservation of organic grapes / Doutorado / Tecnologia Pós-Colheita / Doutor em Engenharia Agrícola

A jaboticaba é uma fruta tipicamente brasileira, pertencente à família Myrtaceae, com grande potencial comercial. Este trabalho teve dois objetivos: (1) entre cinco espécies (Rajada, Coroa, Açu, Sabará e Paulista), quais seriam mais adequadas para consumo in natura, ou para utilização industrial. Para isso, foram avaliadas os aspectos de composição alimentar, sensoriais e pós-colheita dos frutos das cinco espécies, submetidas a armazenamento em diferentes temperaturas (20°C, 12°C 6°C). Num segundo experimento, a espécie Sabará, largamente cultivada, foi submetida aos tratamentos de raleamento de flores, frutos, de flores & frutos e controle (sem raleamento). Os frutos resultantes dos tratamentos, tiveram suas características físicas, químicas e sensoriais avaliadas tanto no fruto recém colhido quanto após armazenamento a 6°C. Durante o período de avaliação da vida-de-prateleira, parte dos frutos foi descascada e a polpa, sem sementes, foi congelada em nitrogênio líquido e armazenadas a -80ºC, para as análises de umidade, de carboidratos e de ácidos orgânicos. Os resultados mostram a superioridade dos atributos das espécies Paulista, e Sabará quanto aos açúcares e ácidos e conservação da qualidade durante o armazenamento, o que indica que são as mais adequadas para consumo in natura. Os teores de fibra alimentar indicam as espécies Rajada, Coroa, Paulista e Sabará como alimentos-fonte de fibra. O armazenamento dos frutos a baixa temperatura estendeu a vida-de-prateleira, sendo a temperaturas 6 °C a mais indicada na conservação dos atributos físico-químicos da jaboticaba. O segundo experimento mostrou que as frutas que sofreram tratamento do raleio tiveram o dobro da vida-de-prateleira em relação ao controle. As frutas que sofreram o raleio de \"flores & frutos\", tiveram os melhores resultados quanto a perda de massa fresca, quanto aos teores de ácidos orgânicos, açúcares solúveis e análise sensorial ao final do armazenamento. A prática do raleio combinada ao armazenamento a baixas temperaturas, propiciou a melhor vida-de-prateleira entre as condições experimentadas. Na avaliação sensorial, a amostra T3 também teve maior aceitabilidade entre os provadores. / Jaboticaba is a typical brazilian fruit that belongs to Myrtaceae family with a high trade potential. This work aimed two purpouses: (1) choose among five species (Rajada, Coroa, Açu, Sabará and Paulista) which of them could be the most appropriated to in natura consumption or which are most appropriated to industrial processing. Hence, fruits of these five species submitted to different temperatures (20°C, 12°C e 6°C) were evaluated about their nourishing, sensorial and postharvest composition. In a second experiment, the widely cultivated Sabará specie, was submitted to flower trimming, fruit trimming, flower & fruit trimming and control (without trimming). The recently harvested fruits obtained from those treatments were evaluated to their physical, chemical, and sensorial characteristics as well as the fruits stored at 6°C. During shelf-life evaluation period, part of the fruits were peeled. The pulps without seeds were frozen using Iiquid nitrogen and stored -80°C and analyzed subsequently to moisture, carbohydrate and organic acid contents. Results show the highest attributes of Paulista and Sabará species in terms of sugar and organic acid contents as well as storage quality, showing that they are most indicated to in natura consumption. Dietary fiber contents of Rajada, Coroa, Paulista and Sabará species indicated that they are good fiber sources. Low temperatures of storage extended fruits shelf-life, being 6°C the storage temperature most indicated to the conservation of jaboticaba physical-chemical attributes. The second experiment showed that fruits which were submitted to trimming treatment had shelflives two times longer than controls. Fruits that were submitted to \"flowers & fruits\" trimming had the best results about fresh mass loss, organic acids content, soluble sugar content and sensorial analysis at the end of storage. The trimming practice along with low temperatures of storage rendered the Best shelf-life among ali storage conditions tested. Sample T3 also showed the best acceptance among the testers.

A mandioca (Manihot esculenta Crantz) é uma raiz originária e cultivada na América do Sul, com alta perecibilidade no período pós-colheita. Seus principais processos de deterioração envolvem reações enzimáticas, oxidativas e microbiológicas. Neste trabalho foram estudadas raízes de mandioca da variedade Zolhudinha catalogada pela EMBRAPA como IM-158, provenientes da região amazônica, que se destacam pela alta atividade amilolítica. Foram analisadas as condições físico-químicas junto com o isolamento e purificação da &#945;-amilase da raiz e a possível participação desta enzima no processo deteriorativo pós-colheita. Por ser uma variedade de mandioca não comercial, o tempo de cocção foi em média de 4,30 h, teor de umidade em tomo de 64 % e porcentagem de amido de cerca de 30 %. A atividade amilásica decai em 1/3 de sua intensidade no quinto dia pós-colheita, em contraponto a formação de açúcares redutores, cuja concentração aumenta cinco vezes. A purificação foi obtida com duas etapas cromatográficas, com DEAE-celulose e Sephacryl S-200, revelando duas isoenzimas de &#945;-amilase treze vezes mais purificadas, com recuperação protéica de 7,5 % e com pesos moleculares entre 14 e 19 kDa. / Cassava (Manihot esculenta Crantz) is a root from a native plant, cultivated in South América, that is hightly perish on the post-harvest time. The mechanisms of the root deterioration are due to enzymatic and oxidative reactions as well as the microbiological attack. In this work were studied roots of Zolhudinha variety, EMBRAPA - IM 158, cultivated in Amazonian area, which distinguishes from others varieties by its higher amylase activity. Physicochemical properties were analyzed during the post-harvest time, the purification of &#945;-amylase were performed to establish a possible involvement on the deteriorative process. As a non-commercial variety, the cooking time of the roots was 4.30 hours on average, with 64 % of water content and 30 % of starch. The amylase activity during the post-harvest decrease 1/3 from the original at the day 5, that matches with the reducing sugar in roots by increase of five times. The purification was achieved by two chromatography steps on DEAE-cellulose and Sephacryl S-200, providing two isozymes of &#945;-amylase, thirteen times more purified with a recovery of 7.5 % of the protein fraction, the estimated molecular weights were between 14 and 19 kDa.

O presente estudo buscou identificar as diversas características da goiaba de polpa branca -\'Kumagai\' e polpa vermelha -\'Pedro Sato\' ensacadas no campo, em relação à qualidade físico-química, à incidência de doenças pós-colheita e ao custo de produção. O experimento foi realizado no município de Valinhos, interior do estado de São Paulo, e as análises laboratoriais foram feitas na Escola Superior de Agricultura \"Luiz de Queiroz\". Com o objetivo avaliar a qualidade físico-química, as goiabas foram ensacadas em dois estádios de desenvolvimento, com 1,5 e 3,0 cm de diâmetro. O ensacamento foi feito com saco de papel branco simples, saco de papel-branco duplo, tecido-não-tecido (TNT), e frutos sem ensacamento, marcados como controle. A metodologia utilizada avaliou o peso do fruto, o diâmetro do fruto, a coloração da casca, a coloração da polpa, a firmeza da polpa, o teor de sólidos solúveis, a acidez titulável e o teor de ácido ascórbico. Após a colheita, os frutos foram mantidos por uma semana em temperatura ambiente controlada (25º C) e avaliados quanto à incidência doenças pós-colheita, de pinta-preta (Guignardia psidii) e antracnose (Colletotrichum spp.); presença ou ausência de larvas de moscas-das-frutas (Anastrepha spp. e Ceratitis capitata) e acúmulo de resíduos químicos aplicados no controle de insetos e de doenças. Por fim, avaliou-se a sustentabilidade econômica da produção de goiabas, pela comparação do custo de produção entre os sistemas de cultivo com e sem ensacamento dos frutos. Para a cultivar Kumagai, o ensacamento com papel duplo proporcionou precocidade na maturação dos frutos e para a cultivar Pedro Sato os ensacamentos com papel simples e com TNT foram os que proporcionam essa precocidade. O ensacamento atuou de forma a evitar a incidência de antracnose para as duas qualidades de goiaba, entretanto, propiciou o aumento na incidência de pinta-preta na pós-colheita de frutos da cultivar Kumagai. O custo total para a produção de goiabas ensacadas foi 8,6% mais elevado do que para a goiaba não ensacada, no entanto, ambas as formas de produção apresentaram-se viáveis economicamente. / This research sought to identify several characteristics of white pulp gravas - \'Kumagai\' and red pulp guavas - \'Pedro Sato\', in relation to physic-chemical quality, incidence of post-harvest diseases and production costs. In order to fulfill the objectives, the experiment was conducted in Valinhos - SP, and the laboratorial analysis was performed at Escola Superior de Agricultura \"Luiz de Queiroz\". To evaluate physic-chemical qualities of two varieties of guava the fruits was bagged at two different development stages, 1,5 and 3,0 cm of fruit diameter. The bagging was realized using a simple white paper bags, double white paper bags and non-textured fabric (TNT). The non-bagged fruits were noted as control. The used methodology evaluated the weight of single fruit, fruit diameter, skin and pulp color, pulp firmness, sugar concentration, acidity, and ascorbic acid levels. In post-harvest guavas, the fruits were kept for one week at controlled temperature (25 ºC) and evaluated for the occurrence of the black spot disease (Guignardia psidii) and anthracnose (Colletotrichum spp.); for the presence or absence of larvae of fruit flies (Anastrepha spp., and Ceratitis capitata); and the abundance of chemical residues, applied to control insects and diseases in guavas. Finally, the economic sustainability of guava production was evaluated, through the comparison of the production costs of both bagging and non-bagging systems. The main results suggests that bagging with double white paper bags induced a shortening in the ripening process of \'Kumagai\' guavas; while in the \'Pedro Sato\' guavas, the shortening ripening process was induced by a simple white paper and TNT bags induced. The bagging process avoided anthracnose incidence in both varieties, although the bagging has resulted in the occurrence of black spot in post-harvest of Kumagai cultivar fruits. The production cost of bagged fruits was 8.6% higher than non-bagged fruit, however, both production systems have shown to be economically sustainable.

Com o objetivo de estudar a eficiência de herbicidas dessecantes, o momento ideal de aplicação, a viabilidade da antecipação da colheita e seus efeitos sobre o rendimento e as qualidades fisiológica e sanitária de sementes de feijão, foi instalada uma pesquisa em Área Experimental e no Laboratório de Análise de Sementes do Departamento de Produção Vegetal da Escola Superior de Agricultura "Luiz de Queiroz" em Piracicaba - SP. Para tanto, utilizou-se o cultivar Pérola, o qual foi semeado na safra da "seca", na população aproximada de 200.000 plantas/ha. O delineamento experimental foi o de blocos casualizados com quatro repetições em esquema fatorial 5 x 5, sendo cinco herbicidas, combinados com as cinco épocas de aplicação (28, 32, 36, 40 e 44 dias após o florescimento) e uma testemunha (sem aplicação de herbicida dessecante). A análise dos dados e a interpretação dos resultados obtidos permitiram as seguintes conclusões: os herbicidas dessecantes Paraquat e Paraquat associado a Diuron proporcionaram antecipação da colheita em onze dias, sem causar danos ao rendimento e a qualidade das sementes, enquanto para Glifosate e Glifosate + uréia a antecipação foi de seis dias; os herbicidas dessecantes Paraquat e Paraquat associado a Diuron não afetaram nem o rendimento, nem a qualidade das sementes produzidas, independemente da época de aplicação; os herbicidas Glifosate e Glifosate mais uréia somente quando aplicados aos 44 dias após florescimento não afetaram a qualidade das sementes e o herbicida dessecante Glufosinato de Amônio, independentemente da época de aplicação, afetou negativamente a qualidade das sementes produzidas. / Viewing to study the efficiency of desiccant herbicides, the ideal moment for their application, the feasibility of anticipating the harvest and their effects on yield and the physiological and sanitary quality of common bean seeds, an experiment was conducted at the College of Agriculture "Luiz de Queiroz", in Piracicaba, state of São Paulo, Brazil. Seeds of the cultivar 'Pérola' were sown during the dry season so as to result in a population of 200,000 plants/hectare. The experimental design was a randomized complete block with four replications in a 5 X 5 factorial arrangement - 5 herbicides in combination with 5 moments of application (28, 32, 36, 40, and 44 days after flowering) and a control treatment (no desiccant was applied). The statistical analyses of the data and the interpretation of the results allowed the following conclusions: Paraquat and Paraquat plus Diuron permited an 11 days anticipation in the harvest with no harm to seed quality or reduction in yield. For Glyphosate and Glyphosate plus Urea the anticipation was of 6 days. Paraquat and Paraquat plus Diuron were not harmful to seed quality or caused yield reduction in none of the moments of application. Glyphosate and Glyphosate plus Urea were not harmful only when applied 44 days after flowering. Ammonium Gluphosinate was always harmful to seed quality independently on the moment of application.