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The principal objective of agriculture is the production of a high yield of healthy crops. This yield may be improved by the automatic detection of diseases and the consequent reduction in the use of pesticides. A digital processing system for images was thus developed and used to identify lesions on the leaves of cotton plants. A collection of 60,659 images of sub-metric resolution showing samples of soil and both healthy and damaged leaves was obtained and processed with an algorithm for the extraction of texture from 102x102-pixel samples. Then they analyzed with a neuro-fuzzy classifier trained to discriminate the three types of regions (soil, healthy leaf, and lesioned leaf). The algorithm developed was able to recognize the three classes. It generated a great amount of information on recognition of background which was more consistent than leaf damage areas. Therefore, it surpassed the performance of areas of healthy leaves. A similar trend was found for sensitivity. The overall accuracy of the system was 71.2%, suggesting that the unbalanced data of the different classes had skewed the results of the algorithm, as the number of false positives for the less well represented classes was greater. The analysis of unbalance (F-Score) showed that, independent of the volume of data, the attributes of texture utilized yielded better results for the images containing areas of damage in relation to overall accuracy. Therefore, given the challenges involved in the automatic identification of lesions in agricultural crops, such as variations in illumination, color, and texture, as well as obstruction, overlapping, and complexity of the region of which the image was taken, the behavior of the model was deemed satisfactory. Given the hybrid nature of the model, it should contribute to the state of the art in the use of intelligent systems in agriculture. This algorithm is available at https://github.com/rafaeufg/Cotton-diseases

Background The San Francisco Valley region from Brazil is known worldwide for its fruit production and exportation, especially grapes and wines. The grapes have high quality not only due to the excellent morphological characteristics, but also to the pleasant taste of their fruits. Such features are obtained because of the climatic conditions present in the region. In addition to the favorable climate for grape cultivation, harvesting at the right time interferes with fruit properties. Results This work aims to define grape maturation stage of Syrah and Cabernet Sauvignon cultivars with the aid of deep-learning models. The idea of working with these algorithms came from the fact that the techniques commonly used to find the ideal harvesting point are invasive, expensive, and take a long time to get their results. In this work, convolutional neural networks were used in an image classification system, in which grape images were acquired, preprocessed, and classified based on their maturation stage. Images were acquired with varying illuminants that were considered as parameters of the classification models, as well as the different post-harvesting weeks. The best models achieved maturation classification accuracy of 93.41% and 72.66% for Syrah and Cabernet Sauvignon respectively. Conclusions It was possible to correctly classify wine grapes using computational intelligent algorithms with high accuracy, regarding the harvesting time, corroborating chemometric results. © 2020 Society of Chemical Industry.

Weeds interfere in agricultural production, causing a reduction in crop yields and quality. The identification of weed species and the level of infestation is very important for the definition of appropriate management strategies. This is especially true for sugarcane, which is widely produced around the world. The present study has sought to develop and evaluate the performance of the Bag-of-Features (BoF) approach for use as a tool to aid decision-making in weed management in sugarcane production. The support vector machine to build a mathematical model of rank consisted of 30553 25x25-pixel images. Statistical analysis demonstrated the efficacy of the proposed method in the identification and classification of crops and weeds, with an accuracy of 71.6% and a Kappa index of 0.43. Moreover, even under conditions of high weed density and large numbers of overlapping and/or occluded leaves, weeds could be distinguished from crops This study clearly shows that the system can provide important subsidies for the formulation of strategies for weed management, especially in sugarcane, for which the timing of weed control is crucial.

The challenges of modern agriculture have led to the development of localized management tools which allow the rationalization of the use and application of pesticides, a reduction in production costs and the optimization of agricultural processes. This study was carried out to develop an algorithm capable of orienting weed control in the management of a corn crop, using digital image analysis to identify the level of weed infestation in the field. The seeds of six species of weed were sown in an experimental plot of corn, and daily images were captured for 40 days for the evaluation of the level of weed infestation (low, intermediate or high). The algorithm developed was able to target information about the plants and soil accurately and discriminate the residual information as referring to either the culture or weeds. The proposed algorithm has achieved 90% accuracy in identifying the level of infestation from images already evaluated by experts. The results can thus be used as part of weed control strategy, with the incorporation of the geographic coordinates of the image making possible the construction of a map of the level of weed infestation in the different areas where the crop is growing.

The determination of the period of harvest is essential in the vineyard. For that, attributes of quality such as Total Soluble Solids (TSS) and phenolic compounds are constantly monitored along the maturation. This work proposes a new non-destructive approach for prediction of TSS, total anthocyanins and yellow flavonoids using RGB images, called IRIS-GRAPE. It is inspired by the process of biometric recognition using the iris. In order to validate the proposed approach, a study comparing its performance with the traditional method was performed, using the average of RGB pixel values of the region of interest (ROI) as input variables for a multiple linear regression. The study used two performance evaluation metrics: the correlation coefficient ( r P ) and the mean square error (MSE). In order to compare the performance differences between the proposed approach, IRIS-GRAPE, and the traditional approach, hypothesis tests were done. The results show that the proposed approach has a superior performance than the traditional method with a confidence level of 95%.

The partial dehydration of grapes after harvest and aimed wine-making, has been shown to be a process that brings increased concentration of sugar and phenolic compounds in the must, which results in the quality of the wines produced. However, the works developed so far studied the process for temperatures up to a maximum of 25°C and air velocity less than 1 m.s-1. This study aimed to analyze the physical and chemical changes (concentration of total soluble solids (TSS) and phenolic compounds (CPC)) after partial dehydration of 'Niagara Rosada' grapes at the temperature subjected to two treatments combining two temperatures and one air velocity (T1= 22.9°C/1.79 m.s-1 and T2 = 37.1°C/1.79 m.s-1), and relative humidity of approximately 40%. The loss of water in the grapes was approximately 14% and the drying process lasted between 20 to 50 h for the treatments T1 and T2, respectively. We experimentally and statistically verified that the treatments promoted significant increase in TSS and CPC; however, for CPC at the temperature of 37.1°C, the increase accounted for approximately 29%, whereas, for the temperature of 22.9°C, it was only 5%. For TSS, the increase was on average 14.4 ± 3.9% between both treatments. Key words: Chaptalization, temperature, air velocity, winemaking.

A potência de sinal é um importante parâmetro a ser considerado em um projeto de implantação de rede de sensores sem fio no meio agrícola. Este trabalho tem como objetivo coletar dados de qualidade de sinal transmitido entre uma estação base e um nó sensor situado no interior de uma casa de vegetação, localizada no campo experimental da Faculdade de Engenharia Agrícola - UNICAMP, com o auxílio de ferramentas computacionais. Após a implantação do nó sensor foram realizados experimentos com vista a se verificar alcance e qualidade do sinal de acordo com sua potência. Através desses ensaios foi possível concluir que uma potência de sinal com valor de -12,2 dBm é suficiente para manter a transmissão entre a estação base e nó sensor. Testes também foram realizados com uma potência de sinal de -9,2 dBm e mostraram que a rede possuía qualidade classificada "muito alta" porém, através do teste de duração da bateria, nota-se que existe economia de energia ao se utilizar a potência de sinal de -12,2 dBm. Foi avaliada a influência que o valor da potência de sinal tem sobre a qualidade do sinal de transmissão e recepção, o gasto de bateria e o alcance do sinal. The signal strength is an important parameter to be considered in a project to establish network of wireless sensors in an agricultural environment. This work aims to collect quality data signals transmitted between a base station and a sensor node located inside a greenhouse, which is an experimental field located in the College of Agricultural Engineering - UNICAMP, with the help of computational tools. After sensor node deployment, experiments were performed in order to check range and signal quality. Through these experiments, it was concluded that a radiofrequency power value of -12.2 dBm is sufficient to maintain transmissions between base station and the sensor. Tests were also performed to a radiofrequency power of -9.2 dBm, and showed that the network had quality rated as "very high". However, by testing the battery life, it is noted that there is an energy saving when the radiofrequency power of -12.2 dBm is used. It was shown that the value of the signal strength has an influence on the quality of signal transmission and reception, battery depletion and signal range.

A aplicação de técnicas de automação e controle em casas de vegetação teve início nos anos 50, com o controle da temperatura através de termostatos; desde então, as mudanças tecnológicas têm abarcado todos os aspectos que compõem o sistema, do projeto estrutural até aspectos relacionados à sustentabilidade. Dentre os parâmetros que devem ser controlados, a temperatura e umidade relativa do ar, a radiação solar, a concentração de CO2, a ventilação e a fertigação têm tido uma evolução significativa, dos quais se apresenta uma panorâmica através da revisão do estado da arte de trabalhos publicados nessas temáticas, nos últimos anos. Na atualidade, temas relacionados com a redução do impacto ao meio ambiente e a produção eficiente e com qualidade, estão levando as casas de vegetação ao caminho da Agricultura de Precisão.

Apresenta-se o desenvolvimento de um equipamento microprocessado, com saída de corrente, para controle da velocidade de rotação do motor do ventilador de sistemas de ar forçado, usando inversor de freqüência. Através de programação (software IHM.EXE), o usuário pode definir a massa a ser resfriada em quilogramas de produto. O equipamento calcula, através de um polinômio previamente estabelecido e programável, a freqüência de operação do inversor, que corresponde a uma vazão de ar específica, dentro dos limites estabelecidos no projeto. O equipamento foi instalado num sistema de resfriamento com ar forçado, estimando-se, pelo cálculo da variação da potência útil mecânica, uma economia de energia da ordem de 82%, com uma rotação equivalente a 56% da nominal do ventilador, proporcionando, desta forma, uma economia significativa no custo de operação do sistema. The development of micro processed equipment is presented, with current exit for control of the speed of rotation of the fan motor of the system of forced air, using investing of the frequency. Through programming (software IHM.EXE), the user can define the mass to be cooled, in kilograms of the product. The equipment calculates through a programmable polynomial previously defined, the frequency of operation of the investor which corresponds to air specific flux, within the limits of the project. The equipment was installed in a forced-air cooling system, being considered by the calculation in useful mechanical power, the energy savings is estimated at around 82% with a rotation equivalent to 56% of the fan nominal, thus providing significant savings in system operating costs.

Este trabalho apresenta as curvas de resfriamento de banana-prata (Musa balbisiana Colla) e os valores do tempo de meio e sete oitavos de resfriamento, partindo do cálculo da Taxa Adimensional de Temperatura. Os frutos foram resfriados num sistema com ar forçado a 7ºC, umidade relativa de 87,6±3,8%, e velocidade do ar entre 1 e 0,2 m/s. Aplicou-se um delineamento experimental inteiramente casualizado, usando um esquema fatorial 2x2 (dois fluxos de ar (fatores) e duas embalagens (níveis)), para um nível de significância de 10%. Os fluxos de ar foram 1.933 a 1.160 m³/h, e as embalagens se diferenciaram pela porcentagem de área de abertura disponível para a ventilação (40 e 3,2%). Foi constatada uma diferença significativa no tempo de resfriamento, tanto quando aplicadas as duas taxas de ar como quando usadas as duas embalagens. O menor tempo de resfriamento foi atingido no tratamento que combinou a maior taxa de ar (1.933 m³/h) com a embalagem de maior área de aberturas (40%). O maior tempo de resfriamento foi atingido no tratamento que combinou a menor taxa de ar (1160 m³/h) com a embalagem de 3,2% de área efetiva de abertura. Os resultados obtidos demonstram que o tempo de resfriamento depende, em grande medida, da taxa de ar e do tipo de embalagem usada. O tempo de resfriamento variou em média entre 117 a 555 min, dependendo do tratamento aplicado. Não se constatou diferença significativa nas perdas de massa entre os diferentes tratamentos. This work presents the cooling curves for bananas Prata, (Musa balbisiana Colla), and determinates half-cooling and seven-eight cooling times and the cooling rate. Bananas were kept in a cold room with a forced-air system at 7ºC and RH = 87.6±3.8%. The experiment was conducted in a 2x2 factorial design, to test the effects of two flow rates (factors) of air passing through the product, and two types of boxes (levels). The statistical analysis was performed at p

As perdas de produtos hortícolas no Brasil são significativas e dentre as causas cita-se o uso de caixas inadequadas e ausência da cadeia do frio. Propõe-se um método de projeto de caixas, baseado em simulação computacional, otimização e validação experimental, minimizando o volume de madeira, associado a aspectos estruturais, ergonômicos e distribuição da área de aberturas. Foram projetados e construídos três protótipos de caixas (ripas retas com diferentes configurações e área efetiva de abertura de 54% e 36%). A eficiência do resfriamento de mangas variedade Tommy Atkins (Mangifera Indica L.), foi avaliada determinando o tempo de resfriamento, acondicionando as frutas nas caixas de madeira desenvolvidas e de papelão usadas comercialmente, resfriadas com ar forçado à temperatura de 6ºC e umidade relativa média de 85,4±2,1%. Foi aplicado o Método de Elementos Finitos, para dimensionamento e otimização estrutural do modelo com melhor comportamento durante o resfriamento. Todas as caixas de madeira foram submetidas a ensaios de vibração, por duas horas (freqüência de 20 Hz). Não houve diferença significativa no tempo de resfriamento das frutas nas caixas de madeira (38,00±1,70 min), no entanto houve diferença significativa nas caixas de papelão (82,74±29,58 min). O modelo submetido à otimização estrutural (6% área efetiva e duas ripas laterais) teve diminuição de volume de 60% e 83% de redução da seção transversal das colunas, com relação às condições iniciais. Não houve incidência de danos de mecânicos nas frutas após a vibração. A simulação computacional e estrutural pode ser ferramenta de apoio para desenvolver projetos de caixas, com grande aproximação, atendendo a critérios geométricos, ergonômicos e térmicos. Losses of horticulture product in Brazil are significant and among the main causes are the use of inappropriate boxes and the absence of a cold chain. A project for boxes is proposed, based on computer simulations, optimization and experimental validation, trying to minimize the amount of wood associated with structural and ergonomic aspects and the effective area of the openings. Three box prototypes were designed and built using straight laths with different configurations and areas of openings (54% and 36%). The cooling efficiency of Tommy Atkins mango (Mangifera Indica L.) was evaluated by determining the cooling time for fruit packed in the wood models and packed in the commercially used cardboard boxes, submitted to cooling in a forced-air system, at a temperature of 6ºC and average relative humidity of 85.4±2.1%. The Finite Element Method was applied, for the dimensioning and structural optimization of the model with the best behavior in relation to cooling. All wooden boxes with fruit underwent vibration testing for two hours (20 Hz). There was no significant difference in average cooling time in the wooden boxes (36.08±1.44 min); however, the difference was significant in comparison to the cardboard boxes (82.63±29.64 min). In the model chosen for structural optimization (36% effective area of openings and two side laths), the reduction in total volume of material was 60% and 83% in the cross section of the columns. There was no indication of mechanical damage in the fruit after undergoing the vibration test. Computer simulations and structural study may be used as a support tool for developing projects for boxes, with geometric, ergonomic and thermal criteria.

Este trabalho propõe um método de projeto de embalagem para produtos hortícolas, buscando uma otimização integrada dos aspectos geométricos, estruturais e térmicos, ligados à facilitação do resfriamento e armazenamento refrigerado. Para o dimensionamento e otimização estrutural, foi utilizado o Método dos Elementos Finitos implementado pelo programa ANSYS, obtendo-se oito modelos virtuais de embalagens, com 10% e 14% de área efetiva de aberturas e geometria quadrada, retangular e circular. Para o desenvolvimento dos experimentos, que avaliaram a relação da área de aberturas com o tempo de sete-oitavos de resfriamento, foram construídos protótipos de tábuas de madeira (Pinnus elliotti) de reflorestamento. Nas embalagens, foram acondicionados aproximadamente 13 kg de banana variedade Nanica (Musa cavendishii, cultivar nanica), resfriada num túnel de ar forçado (vazão de ar de 0,32 m³ s-1, temperatura de 8,0±1,2ºC e umidade relativa de 84,5±2,6%). O tempo de resfriamento também foi comparado com aquele obtido quando a mesma quantidade de frutas foi resfriada em embalagens de papelão (2,5% de área efetiva de abertura) e madeira (18% de área efetiva de abertura). Os resultados demonstraram que, entre os protótipos propostos, não houve diferença significativa no tempo de resfriamento dos frutos acondicionados nas embalagens desenvolvidas, sendo o tempo médio de resfriamento de 40,71±2,81 min. Na comparação com as embalagens de papelão e madeira, houve diferenças significativas, sendo que as embalagens comerciais tiveram tempos de resfriamento de 1,25 e 2 vezes maiores. Concluiu-se que a simulação estrutural computacional, aliada a algoritmos de otimização, além de procedimentos experimentais ligados à cadeia do frio, são recursos promissores no auxílio de projetos para embalagens de transporte de produtos hortícolas. This study proposes a methodology for designing boxes for agricultural products based on computational simulation and experimental validation, seeking the integrated optimization of geometric, structural and thermal aspects associated with cooling and refrigerated storage. The Finite Element Method was used for structural dimensioning and optimization. It was implemented using the ANSYS program, obtaining eight virtual models with 10% and 14% of effective opening area with square, rectangular or circular geometry. In order to develop the experiments that evaluated the relation between effective opening area and seven-eighths cooling time, the prototypes were built using reforestation wood (Pinnus elliotti). Approximately 13 kg of bananas (Musa cavendishii cultivar nanica) were packed in the boxes and cooled in a forced-air tunnel (air flow of 0.32 m³ s-1, temperature of 8.0±1.2ºC and relative humidity of 84.5±2.6%). Cooling time was also compared with the one obtained when the same amount of bananas was cooled in the boxes used to transport and store bananas commercially (cardboard box with 2% of effective opening area and a wooden box called " torito" with 18% of effective opening area). The results showed no significant differences in cooling time of bananas packed in boxes with circular, square and rectangular opening, with average cooling time of 40.71±2.81 min. However, when compared with cardboard and torito boxes, there was a significant difference in cooling time of 1.25 to 2 times the time obtained with wooden boxes. In the structural optimization of the EC-60 box (twelve 60 mm in diameter side orifices and 10% of effective opening area); material volume was reduced in 67.3% in relation to the project initial conditions. In compression tests, the box rupture occurred at loads between 5.4 kN and 8.1 kN, values 3 to 4 times heavier than the imposed project condition (2.0 kN). The computational simulation with optimization algorithms associated with cooling time experiments are promising resources to help in the box design for transporting products.

Made available in DSpace on 2021-07-14T10:27:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-03. Added 1 bitstream(s) on 2021-07-14T11:30:41Z : No. of bitstreams: 1 S1415-43662005000100012.pdf: 220882 bytes, checksum: 1f7e6d6c93bf15503027528dec713a5a (MD5) Este trabalho teve como objetivo desenvolver um estudo teórico através do modelo matemático de Fourier, em sua forma unidimensional e em coordenadas esféricas, o que é descrito por uma equação diferencial parcial linear de segunda ordem, para a obtenção das curvas e do tempo de resfriamento de frutas esféricas. Utilizou-se o Método das Diferenças Finitas (MDF) segundo o esquema implícito no ambiente computacional Matlab 6.1, analisando-se e comparando os principais resultados através do método de ajuste spline. O modelo matemático foi validado com dados experimentais do resfriamento de laranja Valência num sistema com ar forçado (Q = 1933 m³ h-1, e velocidade em torno de 1 m s-1), com temperatura inicial de 26,57 ºC e resfriada até 1 ºC. Os resultados teóricos obtidos com a simulação foram comparados com os encontrados com a aplicação de um modelo bidimensional desenvolvido em coordenadas esferoidais prolato, com o emprego do Método dos Volumes Finitos (MVF) implementado em Fortran 77. Os dois modelos e métodos aplicados mostram-se aptos para caracterizar o processo de resfriamento das frutas, principalmente em termos de valores práticos específicos, uma vez que geraram resíduos desprezíveis. Apesar destes resultados, o valor do coeficiente convectivo de transferência de calor foi significativamente diferente; tal variação mostra como este coeficiente é sensível a vários fatores do processo de resfriamento e, ainda, que se deve aprofundar as pesquisas para a determinação efetiva do valor do mesmo. The objective of this research was to conduct a study using the Fourier one-dimensional mathematical model, in spherical coordinates, which is described as a second order linear partial differential equation, in order to know the curves and the cooling time of spherical fruits. The implicit Finite Differences Method (FDM) implemented in the computational environment Matlab 6.1 was used, analysing and comparing the main results by the spline method. The validation of the mathematical model was carried out using experimental data of Valencia oranges inside a system with forced air (Q = 1933 m³ h-1 and air velocity around 1 m s-1), at the initial temperature of 26.57 ºC and cooled till 1 ºC. The theoretical results obtained in this way were compared with those obtained from the use of a two dimensional mathematical model, in spheroid prolato coordinates, using the Finite Volume Method (FVM) implemented in Fortran 77 code. Both of these model and methods were able to characterize the cooling process, mainly in terms of the practical specific values, once the residues can be disregarded. Although, the value of the convective heat transfer coefficient was significantly different; this variation shows how this coefficient is sensible to the assumptions of the cooling process and that this research must continue in order to determine its effective value. Universidade Estadual Paulista, Faculdade de Engenharia Agrícola Universidade Estadual Paulista, Faculdade de Engenharia Agrícola

The cooling of fruits and vegetables in hydrocooling system can be a suitable technique. This work aimed to define cooling time for fruits and vegetables of different sizes, presenting practical indexes that could be used to estimate cooling time for produce with similar characteristics. Fruits (orange melon-Cucumis melo, mango-Mangifera indica, guava-Psidium guajava, orange-Citrus sinensis Osbeck, plum-Prunus domestica, lime-Citrus limon, and acerola-Prunus cerasus) and vegetables (cucumber-Cucumis sativus, carrot-Daucus carota, and green bean-Phaseolus vulgaris), were cooled in a hydrocooling system at 1°C. The volume of fruits and vegetables ranged between 8.18 cm³ and 1,150.35 cm³, and between 13.06 cm³ and 438.4 cm³, respectively. Cooling time varied proportionally to produce volume (from 8.5 to 124 min for fruits, and from 1.5 to 55 min, for vegetables). The relationship between volume and time needed to cool fruits (from 1.03 min cm-3 to 0.107 min cm-3) and vegetables (from 0.06 min cm-3 to 0.12 min cm-3) is an index that could be used to estimate cooling time for fruits and vegetables with similar dimensions as those presented in this work.

Este trabalho apresenta um estudo para determinar os custos do resfriamento de laranja Valência (Citrus Sinensis Osbeck) num sistema com ar forçado (Ta=1ºC e UR=88,4±2,0%) e numa câmara convencional. Os frutos foram resfriados condicionados em dois tipos de embalagens, com área efetiva de abertura de 3,5% e 40%. O custo total anual foi determinado com o cálculo dos custos fixos e variáveis da instalação, e o custo total de resfriamento, baseado na quantidade de frutos que podem ser resfriados em cada sistema, num mesmo período. Comprovou-se que o custo de resfriamento chega a ser de 20% a 40% menor quando os frutos são resfriados no sistema com ar forçado, se comparado com o custo quando os frutos foram resfriados no sistema convencional. This paper presents study of the cooling cost of Valencia orange in a forced-air system and room cooling (Ta=1ºC and RH = 88,4±2,0%).The fruits was conditioned in two package with 3,5% and 40% of opening effective area. The annual total cost was determined with the fixed and variable costs of the installation and the cooling total costs with the quantity of cooling products in the each system for the same period. The cooling total cost is the 40 to 20% smaller, if compared with the cost when the fruits cooling in the conventional room.

Este trabalho apresenta um estudo com o qual se pretende comparar o resfriamento de laranja Valência (Citrus Sinensis Osbeck) em três sistemas: ar forçado, água gelada e em câmara de estocagem convencional. O sistema de resfriamento com ar forçado operou com um fluxo de ar de 1933 m³ h-1, a 1ºC e umidade relativa (UR) de 88,4% ± 2,0, com velocidade do ar em torno de 1 m s-1. Nos experimentos com água gelada foi utilizado um sistema de imersão, com capacidade de 0,23 m³ de água, a 1ºC. A câmara de resfriamento utilizada tinha capacidade de 2,90 J s-1. O tempo de meio e de sete oitavos do resfriamento foi determinado partindo-se das leituras da temperatura no centro dos frutos, com duas repetições. O resfriamento do leito de frutos com ar forçado não se mostrou homogêneo, obtendo-se tempos que variaram de 107 a 170 min, dependendo da posição do fruto no interior da embalagem. No sistema com água gelada o resfriamento acontece uniformemente em todo o leito de frutos, sendo o tempo médio de resfriamento de 57 min. Quando os frutos foram resfriados no sistema convencional, o tempo de resfriamento oscilou de 362 e 460 min, oito vezes maior que o obtido com água e três vezes maior com ar forçado. This work presents a study to compare the cooling of oranges with room cooling, forced-air cooling and hydrocooling systems of the Valência orange (Citrus Sinensis Osbeck). The forced-air cooling system operated with an air flow of 1933 m³ h-1, at 1ºC, relative humidity (RH) of 88.4% ± 2.0 and air velocity around 1 m s-1. In the experiments with cold water an immersion hydrocooling system with a capacity of 0.23 m³ of water was used at a temperature of 1ºC, approximately. The half cooling time and seven-eighths cooling time were determined from the temperature data, with two replications. The results showed that the cooling of the bed fruits with forced air is not homogeneous, obtaining a mean between 107 a 170 min, depending on the position of the fruit in the package. In the hydrocooling system, the cooling of the fruits occurs uniformly in the bed, with a mean cooling time of 57 min. In room cooling, the time of cooling was 362 and 460 min, eight times that of hydrocooling system and more than three times that of the forced air cooling time.