ABSTRACT Potassium is a nutrient with the potential to increase plant tolerance to salt stress. The aim of this study was to evaluate the production and quality of kale subjected to salt stress and potassium concentrations in a protected environment. The experimental design was in split plots, with plots composed of five nutrient solutions (control treatment, S1 - standard nutrient solution prepared in low-salinity water, 0.5 dS m-1 (500 mg L-1 of KNO3), and four nutrient solutions prepared in brackish waters (3.5 dS m-1) containing four concentrations of KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1,000 mg L-1), and subplots represented by two leaf kale cultivars (Manteiga and Manteiga da Geórgia). Leaf production variables and post-harvest physical and chemical qualities were evaluated. The saline nutrient solution with the addition of NaCl (S2) reduced production but did not reduce the post-harvest quality of kale. The extra addition of KNO3 at 25% (S3) was efficient in reducing the deleterious effects of salt stress on the variables leaf length, leaf area, leaf production, and number of bunches. The cv. Manteiga da Geórgia was more tolerant to salt stress than the cv. Manteiga. environment control treatment S lowsalinity low salinity water 05 0 5 0. m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3.5 35 3 (3. S2 (S 50 L1, 1, 62 75 1000 000 1,00 L-1) Geórgia. . Geórgia) postharvest post harvest evaluated 25 (S3 length area bunches cv (5 3. (3 6 7 100 00 1,0 2 ( 10

RESUMO O potássio é um nutriente com potencial para aumentar a tolerância das plantas ao estresse salino. O objetivo deste estudo foi avaliar a produção e a qualidade da couve submetida ao estresse salino e às concentrações de potássio em ambiente protegido. O delineamento experimental adotado foi em parcela subdivididas, sendo as parcelas compostas por cinco soluções nutritivas (tratamento controle, S1 - solução nutritiva padrão usando água de baixa salinidade, 0,5 dS m-1 (500 mg L-1 de KNO3), e quatro soluções nutritivas preparadas em águas salobras (3,5 dS m-1) contendo quatro concentrações de KNO3 (S2 - 500 mg L-1, S3 - 625 mg L-1, S4 - 750 mg L-1, S5 - 1.000 mg L-1). As subparcelas foram representadas por duas cultivares de couve folha (Manteiga e Manteiga da Geórgia). Foram avaliadas as variáveis de produção de folhas e qualidades físicas e químicas pós-colheita. A solução nutritiva salinizada com adição de NaCl (S2) reduziu a produção, mas não reduziu a qualidade pós-colheita da couve folha. A adição extra de KNO3 em 25% (S3) foi eficiente para reduzir o efeito deletério do estresse salino sobre as variáveis comprimento de folha, área foliar, produção e número de maços. A cv. Manteiga da Geórgia se mostrou mais tolerante ao estresse salino que a cv. Manteiga. protegido subdivididas tratamento controle S salinidade 05 0 5 0, m1 m 1 m- (50 L1 L L- KNO3, KNO , KNO3) 3,5 35 3 (3, S2 (S 50 L1, 1, 62 75 1000 000 1.00 L1. . L-1) Geórgia. Geórgia) póscolheita. póscolheita pós colheita. colheita 25 (S3 foliar maços cv (5 3, (3 6 7 100 00 1.0 2 ( 10 1.

ABSTRACT Alternative techniques for cultivation without soil are widespread; however, studies comparing hydroponic systems still need to be studied, mainly in semi-arid regions. The present study aimed to evaluate the effect of hydroponic systems on the yield and quality of lettuce cultivars subjected to different electrical conductivities of the nutrient solution. The research was conducted in a greenhouse, adopting a completely randomized design in a 2 × 2 × 3 factorial scheme, being two lettuce cultivars (Cinderela and Rubinela), two electrical conductivities (2.90 and 1.6 dS m-1), and three hydroponics systems (NFT, semi-hydroponic, and floating), with three replications. The number of leaves, leaf succulence, specific leaf area, leaf fresh mass, total dry mass, leaf area, titratable acidity, vitamin C, and soluble solids were evaluated. Cinderela cultivar showed the highest average leaf fresh mass, total dry mass, leaf area, and vitamin C values. The NFT and floating systems provided the highest leaf yield and quality, especially in the solution of 1.60 dS m-1. The semi-hydroponic system provided greater development of the plants with a more concentrated nutrient solution (2.90 dS m-1). widespread however studied semiarid semi arid regions greenhouse scheme Rubinela, Rubinela , Rubinela) 2.90 290 90 (2.9 16 1 6 1. m1, m1 m m-1) NFT, (NFT semihydroponic, semihydroponic hydroponic, floating, floating) replications leaves succulence area mass acidity evaluated values 160 60 m1. m-1 . 2.9 29 9 (2. m- 2. (2 (

RESUMO Técnicas alternativas de cultivo sem solo são difundidas; no entanto, estudos comparando os sistemas hidropônicos ainda precisam ser estudados, principalmente em regiões semiáridas. O presente estudo teve como objetivo avaliar a efeito de sistemas hidropônicos na produtividade e qualidade de cultivares de alface submetidas a diferentes condutividades elétricas da solução nutritiva. A pesquisa foi conduzida em casa de vegetação, adotando delineamento inteiramente casualizado. em esquema fatorial 2 × 2 × 3, sendo duas cultivares de alface (Cinderela e Rubinela), duas condutividades elétricas (2,90 e 1,6 dS m-1), e três sistemas hidropônicos (NFT, semi-hidropônico e floating), com três repetições. Foram avaliados número de folhas, suculência foliar, área foliar específica, massa fresca foliar, massa seca total, área foliar, acidez titulável, vitamina C e sólidos solúveis. A cultivar Cinderela apresentou maior massa fresca de folhas, massa seca total, área foliar, acidez titulável e vitamina C e sólidos solúveis. Os sistemas NFT e floating proporcionaram maior produtividade e qualidade foliar, especialmente na solução de 1,60 dS m-1. O sistema semi-hidropônico proporcionou maior desenvolvimento das plantas com solução nutritiva mais concentrada (2,90 dS m-1). difundidas entanto estudados semiáridas vegetação casualizado 3 Rubinela, Rubinela , Rubinela) 2,90 290 90 (2,9 16 1 6 1, m1, m1 m m-1) NFT, (NFT semihidropônico semi hidropônico floating, floating) repetições folhas específica total solúveis 160 60 m1. 1. m-1 . 2,9 29 9 (2, m- 2, (2 (

Abstract Polysaccharide coating is a biodegradable alternative to conventional packings used for delaying senescence in vegetables. This work investigated the properties of cassava and chitosan biopolymeric film and its use as edible coatings to preserve the shelf-life (7 °C and 70% relative humidity (RH)) of green asparagus, with previous cold storage (1 °C and 90% RH) for 7 days. Based on a previous assessment of the films obtained from a) cassava (2.5%), b) chitosan (0.5%), and c) a blend of cassava-chitosan (Cassava+) (2.5 + 0.5%), it could be verified that cassava-chitosan blend films showed improved barrier property (water vapor transmission rate (WVTR) of 38.06 g/(m2.h)) and mechanical properties, with tensile strength of 0.021 MPa, elongation at break of 1.93% and Young’s module of 0.011 MPa. Cassava+ based coating resulted in a lower weight loss and colour L* parameter and minimized textural changes in basal-section of commercial green asparagus spears during a shelf-life of seven days (7 °C and 70% RH), with previous cold storage. All coated spears maintained overall higher carbohydrate levels than the control, except to sucrose which gradually decreased in basal sections and increased in the apical sections of asparagus spears, irrespective of treatment. Edible coating did not affect asparagine concentrations which steadily increased throughout the shelf-life of the spears. The blend (Cassava+) kept for a longer the green asparagus quality. However, spears under a shelf-life of seven days (7 °C and 70% RH), with previous cold storage under 1 °C and 90% RH conditions, developed tip-rot physiological disorder. vegetables shelflife shelf life ( C 70 (RH) 90 2.5%, 25 2.5% , 2 5 (2.5%) b 0.5%, 05 0.5% 0 (0.5%) c cassavachitosan Cassava (Cassava+ 2.5 (2. 0.5%) water WVTR (WVTR 3806 38 06 38.0 g/m2.h gm2h gmh g/ m2.h g m2 h m g/(m2.h) 0021 021 0.02 MPa 193 93 1.93 Youngs Young s 0011 011 0.01 L basalsection section RH, control treatment quality However conditions tiprot tip rot disorder (RH 9 (2.5% 0.5 (0.5% (Cassava 2. (2 380 3 38. gm m2h mh g/(m2.h 002 02 0.0 19 1.9 001 01 0. (0.5 00 1. (0. (0

Resumo Polímeros naturais, como o polissacarídeo, são uma alternativa biodegradável para a fabricação de novas embalagens, a fim de substituir as embalagens convencionais utilizadas para retardar a senescência em vegetais. Este trabalho investigou as propriedades de filmes biopoliméricos de amido de mandioca e quitosana, e seu uso como revestimentos comestíveis para preservar a vida útil (7 °C e 70% umidade relativa- UR) de aspargos verdes, com ou sem armazenamento prévio refrigerado (1 °C e 90% UR) por sete dias. Com base na avaliação prévia dos filmes obtidos a partir de a) fécula de mandioca (2,5%), b) quitosana (0,5%) e c) uma mistura de fécula de mandioca e quitosana (Cassava+) (2,5 + 0,5%), verificou-se que os filmes da mistura fécula e quitosana apresentaram propriedade de barreira melhorada (taxa de permeabilidade ao vapor d’água de 38,06 g/(m2.h)) e propriedades mecânicas, com resistência à tração de 0,021 MPa, alongamento à ruptura de 1,93% e módulo de Young de 0,011 MPa. O revestimento à base de fécula de mandioca e quitosana resultou em menor perda de massa e valor L*, e minimizou as mudanças de textura na seção basal de hastes de aspargo verde comercial durante a vida útil de sete dias (7 °C e 70% UR), com armazenamento prévio refrigerado. Todas as hastes revestidas mantiveram níveis globais de carboidratos mais elevados do que o controle, exceto para a sacarose, que diminuiu gradualmente nas seções basais e aumentou nas seções apicais das lanças de aspargo, independentemente do tratamento. O revestimento comestível não teve efeito nas concentrações de asparagina, que aumentaram ao longo do período de vida útil. Todas as hastes com vida útil de sete dias (7 °C e 70% UR), com armazenamento prévio refrigerado (1 °C e 90% UR), desenvolveram o distúrbio fisiológico podridão das pontas. naturais polissacarídeo vegetais 7 ( C 70 relativa UR verdes 1 90 2,5%, 25 2,5% , 2 5 (2,5%) b 0,5% 05 0 (0,5% c Cassava+ Cassava (Cassava+ 2,5 (2, 0,5%, 0,5%) verificouse verificou se taxa dágua d água 3806 38 06 38,0 g/m2.h gm2h gmh g/ m2.h g m2 h m g/(m2.h) mecânicas 0021 021 0,02 MPa 193 93 1,93 0011 011 0,01 L L* UR, controle sacarose tratamento asparagina pontas 9 (2,5% 0,5 (0,5 (Cassava 2, (2 380 3 38, gm m2h mh g/(m2.h 002 02 0,0 19 1,9 001 01 0, (0, 00 1, (0

ABSTRACT. Since the composition of honey varies with the species of bee as well as flowering and geographical aspects, this study aimed to evaluate the physicochemical and bioactive properties of Apisand stingless bees’honey from the Brazilian Caatinga. Samples of different species of Apis mellifera L.Meliponini (Melipona subnitida, Frieseomellita varia, Melipona mandacaia, Plebeia sp.) and Apis mellifera L.werecollected from honey producersin the state of Rio Grande do Norte. Honey from A. mellifera and stingless bees showed physicochemical differences in some parameters, especially in moisture, free acidity, HMF, water activity, sugars and electric conductivity. There were no differences in color between honeys from A. mellifera and stingless bees. Honeys fromPlebeia sp., F. varia and A. mellifera showed higher antioxidant capacity followed by honeys fromM. mandacaia and M. subnitida. Flavonoids had little influence on the differentiation of antioxidant activities of stingless bees, while the opposite occurred with the phenolic content, where honeys with the highest levels of phenolic also showed higher antioxidant capacity. ABSTRACT aspects beeshoney Caatinga LMeliponini L Meliponini subnitida sp. sp Lwerecollected werecollected Norte A parameters moisture acidity HMF activity conductivity F fromM M content

ABSTRACT Melon cultivation under saline conditions is a challenge, as the plants can suffer a reduction in fruit production and quality. The aim of this study was to evaluate the production and quality of noble melon fruit fertigated with different saline solutions and K/Ca ratios. The experimental design was of randomised blocks, with treatments arranged in a 3 x 6 factorial scheme, using three melon cultivars (Bazuca, McLaren, County) fertigated with six nutrient solutions [S1 - standard nutrient solution (SNS); S2 - SNS + NaCl (5.0 dS m-1); S3 - S2 enriched with K (50%); S4 - S2 enriched with K (100%); S5 - S2 enriched with Ca (50%); S6 - S2 enriched with Ca (100%)]. At the end of each cultivar cycle, the fruit was harvested and assessed for the following parameters: fresh fruit weight, fruit diameter, internal cavity, pulp thickness, pulp firmness, soluble solids content, titratable acidity, soluble solids/titratable acidity ratio, and vitamin C. Salt stress impaired the physical characteristics of the fruit of the three noble melon cultivars. The nutrient solution enriched with 50% K (S3) did not reduce the effect of salt stress on fresh weight or fruit size in the melon, but afforded an increase in fruit quality. challenge KCa ratios blocks scheme Bazuca, Bazuca (Bazuca McLaren County S1 S [S (SNS) 5.0 50 5 0 (5. m1 m 1 m-1) (50%) 100% 100 (100%) 100%. . (100%)] cycle parameters diameter cavity thickness firmness content solidstitratable ratio C (S3 (SNS 5. (5 m-1 (50% 10 (100% (S ( m- (50 (100 (10 (1

RESUMO A indústria têxtil consome um volume significativo de água no processo de tingimento das fibras. As águas residuais geradas no processamento, além de turvas, devido à presença de corantes que não se fixam na fibra durante o processo de tingimento, são prejudiciais ao ambiente aquático e também aos seres humanos. Esse efluente deve passar por um processo de tratamento antes de ser lançado em corpos hídricos. O tratamento de águas contaminadas com o uso de bioadsorventes possui como vantagens o baixo custo de material e reciclagem de resíduo natural. Baseado no exposto, o objetivo deste trabalho foi avaliar a capacidade de adsorção do corante têxtil Azul Reativo BF-5G em casca de mandioca (Manihot Esculenta Crantz), resíduo proveniente da indústria de farinha de mandioca. A casca de mandioca foi lavada, seca e classificada. Os ensaios de adsorção, em banho finito, foram realizados em diferentes condições de pH, granulometria e temperatura. As capacidades máximas de adsorção, em 24 horas de contato, para as diferentes condições de pH, granulometria e temperatura, foram as seguintes: (qmáx=85,18 mg.g-1; pH=1; 30 °C; 16 mesh); (qmáx=52,30 mg.g-1; pH=0; 30 °C; 32 mesh); (qmáx=92,92 mg.g-1; pH=0; 30 °C; 48 mesh). O processo de adsorção foi espontâneo e exotérmico, o que leva a concluir que a casca de mandioca (Manihot Esculenta Crantz) é um potencial adsorvente para o corante Azul Reativo BF-5G, garantindo economia e praticidade no tratamento desse efluente.

ABSTRACT The textile industry consumes a significant amount of water in the fiber dyeing process. The wastewater generated in the processing, in addition to turbid, due to the presence of dyes that do not stick to the fiber during the dyeing process, are harmful to the aquatic environment and also to humans. This effluent must undergo a treatment process before being released into water bodies. The treatment of contaminated water with the use of bioadsorbers has the advantages of low material cost and recycling of natural waste. Based on the above, the objective of this work was to evaluate the adsorption capacity of the textile dye Blue Reactive BF-5G in cassava peel (Manihot Esculenta Crantz), residue from the cassava flour industry. The cassava peel was washed, dried and classified. The adsorption tests, in finite bath, were carried out under different conditions of pH, granulometry and temperature. The maximum adsorption capacities, in 24 hours of contact, were as follows: (qmax=85.18 mg.g-1; pH=1; 30 °C; 180 rpm; 16 mesh); (qmax=52.30 mg.g-1; pH=0; 30 °C; 180 rpm; 32 mesh); (qmax=92.92 mg.g-1; pH=0; 30 °C; 180 rpm; 48 mesh). The adsorption process was spontaneous and exothermic, which leads to the conclusion that the cassava peel (Manihot Esculenta Crantz) is a potential adsorbent for the Reactive Blue BF-5G dye, ensuring economy and practicality in the treatment of this effluent.

ABSTRACT. The aim of this study was to evaluate the physicochemical quality and bioactive compounds of Apis mellifera honey as well as the alterations in the quality of A. mellifera honey after being used in the feeding of Melipona subnitida colonies. A. mellifera honeys were collected in apiaries, homogenised and used as feed for M. subnitida bees for 30 days. Every five days, honey samples were collected and evaluated for physicochemical characteristics and bioactive compounds. The treatments consisted of natural honeys of A. mellifera and M. subnitida and honey of M. subnitida bee after being fed with A. mellifera honey (modified honey). M. subnitida bees, when fed with honey from A. mellifera, modified some of its characteristics, such as moisture, reducing sugars, diastase activity, colour and flavonoid content. Natural and modified honeys of A. mellifera were similar to each other and different from M. subnitida honey in terms of minerals, free acidity, electrical conductivity, phenolic content and antioxidant activity. Treatments were similar in terms of sucrose, insoluble matter, hydroxymethylfurfural and water activity. In general, the quality attributes of the modified honey were closer to the honey of A. mellifera than to the natural M. subnitida honey.

Resumo O objetivo deste estudo foi determinar o tamanho da amostra mais eficiente necessário para estimar a média dos caracteres de qualidade pós-colheita de mangas ‘Palmer’ colhidas em duas estações. Cinquenta mangas foram coletadas no estágio de maturação 2, no inverno (junho de 2020) e na primavera (outubro de 2020), e avaliadas quanto à massa, comprimento, diâmetros ventral e transversal, L*, C* e hº de casca e de polpa, matéria seca, firmeza, sólidos solúveis (SS), acidez titulável (AT) e relação SS/AT. De acordo com os resultados, o coeficiente de variação (CV) dos caracteres de qualidade dos frutos variou de 2,1 a 18,1%. O maior CV, em ambas as safras, foi observado para a relação SS/AT, enquanto o menor foi reportado para hº da polpa. Para estimar a média dos caracteres físico-químicos de mangas ‘Palmer’, são necessários 12 frutos na colheita de inverno e 14 da primavera, considerando um erro de estimativa de 10% e um intervalo de confiança de 95%. A AT e a relação SS/AT exigiram o maior tamanho de amostra, enquanto L* e hº exigiram o menor tamanho de amostra. Conclui-se que a variabilidade foi diferente entre os caracteres físico-químicas e as estações, implicando que diferentes tamanhos de amostra são necessários para estimar a média de diferentes caracteres de qualidade em diferentes estações.

Abstract The objective of this study was to determine the most efficient sample size required to estimate the mean of postharvest quality traits of ‘Palmer’ mangoes harvested in two growing seasons. A total of 50 mangoes were harvested at maturity stage 2, in winter (June 2020) and spring (October 2020), and evaluated for weight, length, ventral and transverse diameter, skin and pulp L*, C* and hº, dry matter, firmness, soluble solids (SS), titratable acidity (TA) and the SS/TA ratio. According to the results, the coefficient of variation (CV) of fruit quality traits ranged from 2.1% to 18.1%. The highest CV in both harvests was observed for the SS/TA ratio, while the lowest was reported for pulp hº. In order to estimate the mean of physicochemical traits of ‘Palmer’ mangoes, 12 fruits are needed in the winter and 14 in the spring, considering an estimation error of 10% and a confidence interval of 95%. TA and the SS/TA ratio required the highest sample size, while L* and hº required the lowest sample size. In conclusion, the variability was different among physicochemical traits and seasons, implying that different sample sizes are required to estimate the mean of different quality traits in different growing seasons.

RESUMO A indústria têxtil produz efluentes ricos em corantes que, quando liberados em corpos hídricos, dificultam a penetração da luz solar, prejudicando os processos fotossintéticos. Além disso, os corantes foram indicados como substâncias potencialmente tóxicas. Em geral, os processos de remoção desses contaminantes têm sido muito estudados, destacando-se a técnica de adsorção por sua alta eficiência, além de vantagens operacionais e a possibilidade de reutilização de resíduos agrícolas como adsorventes, beneficiando o meio ambiente e reduzindo custos. O presente trabalho teve como objetivo estudar o desempenho do mesocarpo de coco utilizado como adsorvente no processo de branqueamento de efluente sintético contendo 25 g.L-1 de corante vermelho reativo 195. Os adsorventes foram caracterizados por granulometria, análise termogravimétrica e potencial de carga zero. Realizou-se estudo cinético e de equilíbrio, aplicando-se modelos cinéticos e isotermas de adsorção. O adsorvente exibiu eficiência de remoção de 89,92 % em 120 min. A capacidade máxima de adsorção foi de 24,04 g.g-1 a 30 °C. O estudo cinético mostrou que os dados foram melhor ajustados pelo modelo de Elovich, indicando quimissorção lenta. O estudo termodinâmico mostrou que o processo de adsorção é exotérmico e espontâneo para todas as temperaturas avaliadas.

ABSTRACT The textile industry produces dye-rich effluents that when released in hydric bodies hamper the penetration of sunlight, impairing photosynthetic processes. Besides that, dyes have been indicated as potentially toxic substances. In general, the processes of removing of these contaminants have been much studied, with the technique of adsorption standing out for its high efficiency, in addition to operational advantages and the possibility of reuse agricultural waste as adsorbents, benefiting the environment and reducing costs. The present work had as objective to study the performance of coconut mesocarp utilized as adsorbent in the bleaching process of synthetic effluent containing 25 g.L-1 of reactive red 195 dye. The adsorbent were characterized by granulometry, thermogravimetric analysis and zero point charge. Kinetic and balance study was realized, applying kinetic models and adsorption isotherms. The adsorbent exhibited removal efficiency of 89.92 % in 120 min. The maximum adsorption capacity was 24.04 g.g-1 at 30 °C. The kinetic study showed that the data was better adjusted by an Elovich equation, indicating slow chemisorption. The thermodynamic study exhibited that the adsorption process is exothermic and spontaneous for all the temperatures evaluated.

RESUMO Filmes biopoliméricos podem substituir vantajosamente polímeros de origem petroquímica em diversas áreas, como a de embalagem de frutas e hortaliças. Como esses produtos apresentam respiração e transpiração mesmo após a colheita, as propriedades de barreira e de resistência à água do material são cruciais para o cumprimento de seu propósito. Neste trabalho foram obtidos filmes biopoliméricos baseados em fécula de mandioca (0-3%), quitosana (0-3%), cera de carnaúba (0; 0,2%) e glicerol (0,6%) e suas propriedades de interesse foram determinadas. A incorporação da cera reduziu em média 20% a taxa de permeabilidade ao vapor d’água (TPVA), em relação aos filmes sem cera. Dentre os filmes contendo cera, 1c (3% de fécula) e 2c (2% de fécula e 1% de quitosana) apresentaram valores mais baixos de TPVA, 12,55 g/m²h e 12,42 g/m²h respectivamente, sendo então submetidos a outras caracterizações que revelaram que a substituição parcial da fécula pela quitosana não afetou a espessura dos filmes, causou decréscimo de 14% em sua solubilidade e melhorou suas propriedades mecânicas, o que significa aumento em seu potencial para a aplicação pretendida.

ABSTRACT Biopolymer films can advantageously substitute polymers of petrochemical origin in several areas, such as packaging of fruits and vegetables. As these products exhibit breathability and perspiration even after harvesting, barrier properties and water resistance of the packaging material are crucial. In this work, biopolymer films based on cassava starch (0-3%), chitosan (0-3%), carnauba wax (0; 0.2%) and glycerol (0,6%) were obtained and their properties of interest were determined. The wax incorporation reduced on average 20% of the water vapor transmission rate, WVTR, in relation to the films without wax. Among the films containing wax, 1c (3% starch) and 2c (2% starch; 1% chitosan) presented lower values of WVTR, 12.55 g / m²h and 12.42 g / m²h respectively, were then subjected to other characterizations that revealed that the partial replacement of starch by chitosan did not affect the film thickness, caused a decrease of 14% in its solubility and improved mechanical properties, which means increase in its potential for the intended application.

This work aims investigate the changes on tensile properties of biocomposites obtained by addition of carnauba wax and coconut fibers in a corn starch matrix. The influence of carnauba wax and coconut fibers contents on tensile strength, modulus of elasticity and elongation at break was studied using a response surface methodology. A central composite design based on three levels of carnauba wax content (0, 10 and 20 %) and coconut fibers content (0, 10 and 20 %) was elaborated. Empirical models were obtained to describe these properties as function of coconut fiber and carnauba wax contents. Optical microscopy was carried out to visualize the dispersion and interactions between coconut fibers, carnauba wax and starch matrix in the biocomposites. In presence of carnauba wax, the biocomposite became more compact and with a better interaction between the corn starch-based matrix and coconut fibers reinforcement. It was observed that tensile strength and modulus of elasticity rise with the increase in carnauba wax and coconut fiber contents. Moreover, the elongation at break increases with the addition of coconut fiber, while a decrease in the values of this property occurs with the addition of carnauba wax.

Concern for sustainable development has provided significant improvements in the development of biodegradable materials. This work aims to evaluate, through a central composite design (CCD), the mechanical properties of cassava starch-based biocomposites manufactured with different compositions of carnauba wax (CW), sisal fiber (SF) and glycerol (G). The biocomposites were obtained by casting method. The tensile strength (TS), modulus of elasticity (ME) and elongation at break (El) for the biocomposites were determined by tensile tests. Representative models were obtained to explain changes in mechanical properties of biocomposites as function of composition variables. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed to elucidate interactions between the starch matrix and additives A biocomposite with 7.5% sisal fiber, 10% carnauba wax and 10% glycerol showed the best properties to possible applications.

Este trabalho foi desenvolvido objetivando avaliar o efeito da condutividade elétrica da solução nutritiva sobre a qualidade dos frutos em cultivares de maxixeiro. Utilizou-se o delineamento de blocos casualizados, em esquema fatorial 4 x 4, com quatro repetições, sendo quatro cultivares de maxixe (Cucumis anguria) (‘Do Norte’, ‘163’, ‘Liso de Calcutá’ e ‘Liso Gibão’) fertirrigadas com soluções nutritivas apresentando diferentes condutividades elétricas (1,4; 1,9; 2,4 e 2,9 dS m-1). Os frutos foram analisados quanto as seguintes características: sólidos solúveis totais (SST), pH, condutividade elétrica do suco (CEsuco), acidez titulável (AT) e razão SST/AT. Com exceção do pH, as demais características de qualidade do fruto foram afetadas pelo cultivo do maxixeiro nas diferentes soluções nutritivas e de forma diferente para cada cultivar. Os frutos da cultivar ‘163’ apresentam menor SST, pH, CEsuco para a condutividade elétrica da solução nutritiva (Cesn) de 1,4 dS m-1 e relação SST/AT, mas apresentou maior AT e CEsuco para CEsn acima de 1,4 dS m-1). Considerando a relação SST/AT, as cultivares ‘Do Norte’ e ‘Liso de Calcutá’ apresentaram, de forma geral, melhor qualidade para consumo in natura. Frutos com maior razão SST/AT, foram obtidas para todas as cultivares em solução nutritiva com maior condutividade elétrica.

The objective of this work was to evaluate the effect of the electrical conductivity of the nutrient solution on fruit quality in gherkin cultivars. A randomized complete block design was used in a 4 x 4 factorial design, with three replicates, four cultivars (Do Norte, 163, Liso de Calcutá e Liso Gibão) with four concentrations of nutrients in the nutrient solution with different electrical conductivities (1.4, 1.9, 2.4 and 2.9 dS/m). The fruits were harvested at commercial maturity, immature with intense green color and analyzed the following characteristics: soluble solids, pH, electrical conductivity of the juice (CEsuco), titratable acidity and SS/TA ratio. With the exception of pH, the other quality characteristics of the fruit were affected by the cultivation of the gherkin in the different nutrient solutions and of different form for each cultivar. The fruits of cultivar 163 showed lower SS, pH, CEsuco for CEsn of 1.4 dS/m and SS/AT ratio, but presented higher TA and CEsuco for CEsn above 1.4 dS/m). Considering the SS/TA ratio, the cultivars Do Norte and Liso Gibão presented, in general, better quality for in natura consumption. The fruits with better quality, higher SS/TA ratio, were obtained for all cultivars in nutrient solution with higher electrical conductivity.

RESUMO A poda da haste principal e o raleio de frutos são práticas culturais que podem influenciar a produtividade e a qualidade dos frutos produzidos. Este estudo teve por objetivo avaliar a influência da poda da haste principal e do raleio dos frutos na qualidade e conservação pós-colheita de melão Charentais ‘Banzai’. Em campo, as plantas foram submetidas à poda da haste principal e ao raleio dos frutos, com a colheita ocorrendo aos 74 dias após a semeadura (DAS). Os frutos foram levados para o laboratório, onde foram higienizados, caracterizados e armazenados em câmara fria (5 °C e 90 ± 2% UR). Na fase de campo, o experimento foi realizado em parcelas subdivididas utilizando um esquema fatorial 2 × 4 + 1, com dois níveis de poda da haste principal (podada e não podada), quatro níveis de tempo de desbaste (42, 45, 48, e 51 DAS) e um controle (sem poda e sem raleio); enquanto a sub-parcela consistiu de tempos de armazenamento (0, 7, 14, 21, e 28 dias), com quatro blocos. Os tratamentos pré-colheita não influenciaram significativamente as características de produção do híbrido Banzai. O tratamento sem poda elevou a acidez titulável dos frutos e o raleio aos 51 DAS reduziu os sólidos solúveis. Houve redução na firmeza de polpa, acidez titulável e açúcares redutores; e um incremento nos sólidos solúveis, açúcares solúveis totais e açúcares não redutores durante o armazenamento. A poda da haste principal do meloeiro propiciou redução na perda de massa dos frutos aos 28 dias de armazenamento.

ABSTRACT Main stem pruning and fruit thinning are cultivation practices that can influence the yield and quality of the fruit. This study aimed to evaluate the effects of main stem pruning and fruit thinning on the postharvest conservation of Charentais Banzai melons. In the field, the plants were subjected to main stem pruning and fruit thinning, with harvesting done 74 days after sowing (DAS). The fruits were transported to the laboratory where they were cleaned, characterized, and stored in a cold chamber (5 °C and 90 ± 2% RH). In the field, the experiment was designed as a split-plot using a 2 × 4 + 1 factorial design, with two levels of main stem pruning (pruned and unpruned), four levels of thinning times (42, 45, 48, and 51 DAS), and a control (unpruned and unthinned). The sub-plot consisted of storage times (0, 7, 14, 21, and 28 days), with four blocks. The preharvest treatments did not significantly influence the production characteristics of the Banzai hybrid. The treatment without pruning increased the titratable acidity of fruit, and the thinning at 51 days after sowing (DAS) reduced soluble sugars. There was a decline in pulp firmness, titratable acidity, reducing sugars, and an increase in soluble solids, total soluble sugar, and non-reducing sugars during storage. Pruning the main melon stem reduced the weight loss of the fruit after 28 days of storage.

Coatings technologies with biopolymeric films are effective in maintaining the chemical and sensory characteristics of several fruits. Cassava starch is an attractive biopolymeric because of its renewable characteristics and low cost, but it has a high transfer rate of water vapor. Hydrophilic compounds of organically modified montmorillonite clay by ion exchange can be used to improve the limiting properties of starch in exchange for additives such as lipids. The solutions prepared with 5% m/v starch / 5% m/m cationic / anionic clay and uncoated were applied in caja fruit, harvested at physiological maturity, selected for absence of defects and color uniformity. The experimental design was performed with four storage times (0, 3, 6 and 9 days). For the maturation index, there was an isolated effect of the type of coating and storage time, showing the composite films of modified cationic clay with greater MI of the fruits in comparison to the control fruits.