Antonio Gomes Soares

Effect of extrusion-cooking in total carotenoids content in cream and orange flesh sweet potato cultivars

ABSTRACT Sweet potato ( Ipomoea batatas ) is a food crop that suppliesenergy, minerals and vitamins C and B. Some cultivars are very richin carotenoids (pro-vitamin A). In this study were evaluated andcompared the total carotenoids content of two cultivars and the losseson the dehydrated extruded sweet potato flour. Samples from organicand conventional crops were analyzed, in the form of fresh anddehydrated extruded samples. Total carotenoids content of the freshproduct, expressed on wet basis, was of 437 μg 100 g -1 for the creamcultivar and 10,12 μg 100 g -1 for the orange cultivar. Afterdehydration, losses of total carotenoids were of 41% and 38%,respectively. The fresh orange cultivar presented high totalcarotenoids content in comparison to the cream cultivar. The extrudedorange sweet potato flour showed the lowest losses in totalcarotenoids. Therefore, the processed flour of orange sweet potatocould be used to obtain pre-gelatinized extruded flour with high totalcarotenoids content.

Diferenças entre bananas de cultivares Prata e Nanicão ao longo do amadurecimento: características físico-químicas e compostos voláteis

Fresh green bananas [Nanicao (Musa sp., subgroup Cavendish) and Prata (Musa sp., subgroup Prata)] were studied during their ripening. Physical (firmness), physicochemical (pH, total titrable acidity and soluble solids) and chemical properties (sugars, phenolics and volatile compounds) were analyzed and showed significant differences (p < 0.05). Prata presented higher values of phenolic compounds, soluble solids, sugars and firmness than Nanicao. A method to quantify the emission of esters was developed by cryogenic headspace and gas chromatography. Acetates, butyrates, isobutyrates and isovalerates were predominant. Prata produced a higher volatile concentration than Nanicao, except for acetates. In most cases, the amount of volatiles increased continuously until peel browning, followed by a decrease or a plateau.

Emissão de etileno e de CO2 em mamão 'Sunrise Solo' e 'Golden'

Papaya fruits of Sunrise Solo and Golden cultivars were stored at 10oC and 25oC. They were daily evaluated on C2H4 and CO2 production rates, by observing the peel color index increasing. The non increasing of the peel color index, during the 20 days of stored, was influenced by the appropriate refrigeration temperature whose inhibit papayas metabolism. It was noticed in the fourth and between the eighth and ninth day an increasing on respiration and ethylene rates, in the fruits stored at 25oC. The refrigeration decreased the respiration rate and papayas ethylene production, showing a metabolism reduction allowing fruits to present unripe appearance, even after 20 days of storage.

Quantitative analysis of glyphosate, glufosinate and AMPA in irrigation water by in situ derivatization–dispersive liquid–liquid microextraction combined with UPLC-MS/MS

A novel method was developed for the sensitive, cheap and fast quantitation of glyphosate, glufosinate and aminomethylphosphonic acid (AMPA) in irrigation water by in situ derivatization and dispersive liquid–liquid microextraction (DLLME) combined with ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Water samples were filtered with a 0.22 μm nylon filter, pH adjusted to 9 with ammonium bicarbonate and derivatized with fluorenylmethyloxycarbonyl chloride (FMOC-Cl). Afterwards, DLLME was applied to concentrate the compounds of interest, which were then analyzed by UPLC-MS/MS. The best results were obtained when acetone and dichloromethane were used as dispersive and extraction solvents, respectively. Two-level full factorial designs and a central composite design were applied to select the most appropriate derivatization and DLLME conditions. The method performance was evaluated according to the SANTE/11945/2015 guidelines and was linear in the 1.0 to 200 μg L−1 range for glyphosate, glufosinate and AMPA, with r2 ≥ 0.997 and individual residuals <13%. Repeatability (RSDr) and within-laboratory reproducibility (RSDwr) ranged from 2.7 to 9.1% and from 3.4 to 14.3%, respectively, and the trueness between 94.9 and 118.1%. The limits of detection were 0.35, 0.05 and 0.10 μg L−1 for glyphosate, glufosinate and AMPA, respectively and the limit of quantitation was 1.0 μg L−1 for all three compounds. The developed method was successfully applied to the analysis of irrigation water (surface and groundwater). No sign of the three compounds was detected in the groundwater samples but glyphosate was quantified in surface waters.

Response surface methodology for optimization of cyanamide analysis by in situ derivatization and dispersive liquid-liquid microextraction

Cyanamide is widely used for agricultural purposes; therefore, its residues can be found in water. A new method was developed for its quantification using in situ derivatization with 2,6‐dimethyl‐4‐quinolinecarboxylic acid N‐hydroxysuccinimide ester followed by dispersive liquid–liquid microextraction (DLLME) and high‐performance liquid chromatography/fluorescence analysis. Multivariate chemometric techniques were successfully used to obtain the optimum conditions for direct derivatization and DLLME extraction. Derivatization parameters and DLLME extraction conditions were optimized by a two‐step design, 2k factorial design for screening, and central composite design for optimization. Best derivatization conditions were addition of 600 μL of derivatizing reagent, a temperature of 4 ºC, and pH 8.5, whereas for optimum extraction 800 μL of solvent, 30% NaCl conc. w/v, and pH 3.8 were chosen.

Conservação pós-colheita de espigas de milho verde minimamente processado sob diferentes temperaturas

Objetivou-se, neste trabalho, avaliar o efeito de tres temperaturas (5oC, 8oC e 11oC), na qualidade de hibridos de milho verde (Zea maiz L.) com endosperma normal, minimamente processado, durante oito dias de armazenamento, com avaliacoes a cada dois dias. Foram utilizadas espigas de dois hibridos, sendo um comercial da Sementes Agroceres (Ag 1051) e outro do programa de melhoramento da Embrapa Milho e Sorgo (Embrapa HT1). A temperatura de 5oC foi a que melhor preservou a qualidade das espigas dos hibridos de milho verde estudados, por proporcionar perda de massa reduzida e manutencao dos teores de solidos soluveis, frutose e glicose. O hibrido Ag 1051 apresentou menor perda de massa, maiores valores de umidade e maior teor de frutose. O Embrapa HT1 apresentou maiores valores iniciais e finais para os teores de solidos soluveis e maior valor para a coloracao b*. O valor L*, que indica quaoclaro e escuro e produto, tambem diminuiu ao longo do armazenamento, indicando escurecimento das espigas ao longo do armazenamento.

Características físicas e químicas de morango processado minimamente e conservado sob refrigeração e atmosfera controlada

Recebido para publicacao em 16/7/2007 Aceito para publicacao em 12/2/2008 (001726) 1 Embrapa Agroindustria Tropical, CP 13761, CEP 60511-110, Fortaleza CE, Brasil, E-mail: ingrid@cnpat.embrapa.br 2 Embrapa Agroindustria de Alimentos, Av. das Americas, 29.501, Guaratiba, CEP 23020-470, Rio de Janeiro RJ, Brasil 3 Faculdade de Engenharia Agricola, Universidade Estadual de Campinas – Unicamp, Cidade Universitaria Zeferino Vaz, CP 6011, CEP 13083-875, Campinas SP, Brasil, E-mail: benedeti@agr.unicamp.br 4 Departamento de Ciencia dos Alimentos, Universidade Federal de Lavras – UFLA, Lavras MG, Brasil *A quem a correspondencia deve ser enviada Caracteristicas fisicas e quimicas de morango processado minimamente e conservado sob refrigeracao e atmosfera controladaStrawberries cv. Oso Grande were minimally processed and kept in three different atmospheres: 3% O2 + 10% CO2 (N2 balance), 3% O2 + 15% CO2 (N2 balance) and ambient atmosphere (control), at 5 and 10 oC, during 7 days, with the evaluation of their physical and chemical characteristics during storage. Fruits were evaluated at 0, 3 and 7 days for weight loss, firmness, pH, titratable acidity, soluble solids, sugar content (sucrose, fructose and glucose) and total anthocyanins. Data were subjected to analysis of variance (ANOVA) and means were compared by the Least Significance Difference (LSD) test (5%). It was verified that shifting the temperature from 5 to 10 oC had no significant effect on the physical and chemical variables analyzed. The utilization of atmospheres 3% O2 + 10% CO2 and 3% O2 + 15% CO2 was important for quality maintenance of fresh-cut strawberries. They better preserved firmness in relation to ambient atmosphere, and had a positive effect on the control of fruit weight loss. However, fresh-cut fruits kept under those atmospheres showed a lower content of anthocyanins when compared to fruits stored in ambient conditions.

Crescimento in vitro de fungos (Colletotrichum gloeosporioides e Cladosporium cladosporioides) isolados de frutos do mamoeiro, sob atmosfera controlada e refrigeração

ABSTRACT - The use of these combined technologies in tropical fruits does not present satisfactory results yet, most of the time because o fthe fruits injury by chilling. This injury could be intensified under atmospheric control conditions. There are evidences that the controlledatmosphere has fungistatic effect. Therefore, the objective of this work was verifying , in vitro , the influence of controlled atmosphere andtemperature on the two pathogenic fungi from papaya fruit: Colletotrichum gloeosporioides and Cladosporium cladosporioides . Thesefungi had been storage under two temperatures, atmospheres and period of incubation patterns (10oC and 25oC; ambient and contro lled - 3%O 2 and 6% CO 2 ; 7 or 14 days. After this period of storage, the contaminated plates had been incubated at 25oC under environment atmospherefor seven days more. It was verified a small growth of Colletotrichum gloeosporioides under refrigeration, also after additional period at 25oC.At 25 o C, the growth of this fungus was also reduced when stored under controlled atmosphere. On the other hand, it was not verifiedsignificant inhibitor effect of the controlled atmosphere at 10oC on the growth of

Nutritional value of organic acid lime juice (Citrus latifolia T.), cv. Tahiti

Acid lime can be used as fresh fruit or as juice to increase the flavor of drinks. Therefore, it is necessary to analyze organic acid lime nutritional composition in order to evaluate if there are important differences among those conventionally produced. No significant differences in total titrable acidity, pH, ascorbic acid, sucrose, calcium, and zinc were found between the acid lime juice from organic biodynamic crops and conventional crops. However, the organic biodynamic fruits presented higher peel percentage than the conventional ones leading to lower juice yield. On the other hand, fructose, glucose, total soluble solids contents, potassium, manganese, iron, and copper were higher in the conventional samples. These results indicated few nutritional differences between organic and conventional acid lime juices in some constituents. Nevertheless, fruit juice from biodynamic crops could be a good choice since it is free from pesticides and other agents that cause problems to human health maintaining the levels similar to those of important nutritional compounds.

Efeito do 1-metilciclopropeno sobre a emissão dos ésteres voláteis de bananas ao longo do amadurecimento

Fresh green bananas (Musa sp., subgroup Prata) were treated with a dose of only 90 ηg g-1 of 1-MCP for 13 hours and the evolution of the volatile compounds along the ripeness was studied. A method to quantify the emission of esters was developed by cryogenic headspace and gas chromatography. Esters of acetate, butyrate, isobutyrate and isovalerate were found as major compounds. The application of the 1-MCP for 13 hours delayed the appearance of the coloration 8 of the peel for 3 days and decreased quantitatively in about 46% the total production of esters in the banana until the 15° day of harvested.