Antioxidant films and coatings based on starch and phenolics from Spondias purpurea L.

The objective of this study was to prepare, for the first time, active films and coatings from fruit starch (SPFS) and phenolic stem bark extract (SBPE) from Spondias purpurea L. Starch film formulations were prepared with different SBPE contents (5-20 wt% on starch), then cast and dried into films. SBPE showed higher antioxidant activity and antimicrobial activity against both Gram-negative and Gram-positive bacteria. Chemical, morphological, thermal, optical, mechanical, and barrier properties were studied for SPFS-SBPE films. In general, the phenolic extract caused significant changes in starch films (especially when in excess), such as gradual reduction of elastic modulus and tensile strength, increased elongation, opacity, and thermal properties (e.g. glass transition and melting enthalpy). On the other hand, SBPE provided the films with active properties (antioxidant and UV-absorbing). Coatings were applied to minimally processed mangoes (MPM), which were stored for 10 days at 12 °C. SBPE-containing coatings provided better protective action, reducing the total color difference (∆E⁎) and delaying the browning index (BI) during storage as well as reducing fungus attack. The active SPFS-SBPE films showed great potential as environmentally friendly active films and coatings.

Xenon lamps used for fruit surface sterilization can increase the content of total flavonols in leaves of Lactuca sativa L. without any negative effect on net photosynthesis.

One (1P), two (2P), three (3P) or four (4P) pulses of light supplied by a xenon lamp, were applied to young lettuce plants grown in pots. The lamp used in the trial was similar to those used for fruit surface sterilization. Total flavonols were measured in leaves using the Dualex method. In a first trial conducted in greenhouse conditions, 6 days after the pulsed light (PL) treatment, flavonols were increased by 312% and 525% in the 3P and 4P treatments, respectively, in comparison to the those in the untreated control. Changes in the chlorophyll fluorescence parameters suggest that the PL treatment may induce limited and transient damage to the photosynthetic machinery and that the damage increases with the increasing number of pulses. The performance parameters were not significantly affected by PL and recovered fully by 6 days after the treatments. The 1P and the 2P treatments 6 days after the treatment showed a 28.6% and a 32.5% increase, respectively, in net photosynthetic assimilation, when compared to that of the control. However, 8 days after the treatment, there was no longer a difference between the treatments and the control in net photosynthetic assimilation. Eight days after the light treatment, the 3P treatment showed a 38.4% increase in maximal net photosynthetic assimilation over that of the control, which is an indication of positive long-term adaptation of photosynthetic capacity. As a whole, our observations suggest that PL could be used on field or greenhouse crops to increase their phytochemical content. No long-lasting or strong negative effects on photosynthesis were associated with PL within the range of doses we tested; some observations even suggest that certain treatments could result in an additional positive effect. This conclusion is supported by a second trial conducted in phytotrons. More studies are required to better understand the roles of the different wavelengths supplied by PL and their interactions.

Development and Validation of a Reversed Phase HPLC Method for Determination of Anacardic Acids in Cashew (Anacardium occidentale) Nut Shell Liquid.

Cashew nut shell liquid (CNSL) contains phenolic lipids with aliphatic chains that are of commercial interest. In this work, a chromatographic method was developed to monitor and quantify anacardic acids (AnAc) in CNSL. Samples containing AnAc were analyzed on a high-performance liquid chromatograph coupled to a diode array detector, equipped with a reversed phase C18 (150 × 4.6 mm × 5 µm) column using acetonitrile and water as the mobile phase both acidified with acetic acid to pH 3.0 in an isocratic mode (80:20:1). The chromatographic method showed adequate selectivity, as it could clearly separate the different AnAc. To validate this method, AnAc triene was used as an external standard at seven different concentrations varying from 50 to 1,000 µg mL-1. The Student's t-test and F-test were applied to ensure high confidence for the obtained data from the analytical calibration curve. The results were satisfactory with respect to intra-day (relative standard deviation (RSD) = 0.60%) and inter-day (RSD = 0.67%) precision, linearity (y = 2,670.8x - 26,949, r2 > 0.9998), system suitability for retention time (RSD = 1.02%), area under the curve (RSD = 0.24%), selectivity and limits of detection (19.8 µg mg-1) and quantification (60.2 µg mg-1). The developed chromatographic method was applied for the analysis of different CNSL samples, and it was deemed suitable for the quantification of AnAc.

Control of browning of minimally processed mangoes subjected to ultraviolet radiation pulses.

The pulsed ultraviolet radiation (UVP) has been used as an alternative strategy for the control of microorganisms in food. However, its application causes the browning of minimally processed fruits and vegetables. In order to control the browning of the 'Tommy Atkins' minimally processed mango and treated with UVP (5.7 J cm-2) it was used 1-methylcyclopropene (1-MCP) (0.5 µL L-1), an ethylene action blocker in separate stages, comprising five treatments: control, UVP (U), 1-MCP + UVP (M + U), UVP + 1-MCP (U + M) e 1-MCP + UVP + 1-MCP (M + U + M). At the 1st, 7th and 14th days of storage at 12 °C, we evaluated the color (L* and b*), electrolyte leakage, polyphenol oxidase, total extractable polyphenols, vitamin C and total antioxidant activity. The 1-MCP, when applied before UVP, prevented the loss of vitamin C and when applied in a double dose, retained the yellow color (b*) of the cubes. However, the 1-MCP reduced lightness (L*) of independent mango cubes whatever applied before and/or after the UVP. Thus, the application of 1-MCP did not control, but intensified the browning of minimally processed mangoes irradiated with UVP.

Qualidade de frutos de noni (Morinda citrifolia L.) cultivados em Trairi-CE / Quality of Noni fruits (Morinda citrifolia L.) grown in Trairi-CE / Calidad de la fruta del noni (Morinda citrifolia L.) cultivado en Trairi-CE

Introdução: o noni é uma fruta que chegou ao Brasil como uma matéria-prima com forte apelo comercial devido a todas as características benéficas a ele atribuídas e os benefícios relacionados ao seu consumo. Objetivo: este trabalho teve como objetivo efetuar a caracterização física e físico-química de frutos de noni no estádio de maturação "maduro" (coloração amarelo esbranquiçado). Métodos: foram colhidos frutos de noni em cinco plantas que se encontram na Fazenda Alberto Antônio, localizada próximo ao município de Trairi, Ceará (Trairi-CE). Para a caracterização do fruto, realizaram-se as seguintes análises: massa fresca do fruto (g), comprimentos longitudinal (mm) e transversal (mm), DL/DT, firmeza (N), vitamina C (mg.100 g-1 de polpa), sólidos solúveis (° Brix), acidez titulável (%), pH e relação SS/AT. Adotou-se um delineamento inteiramente casualizado, em que os tratamentos foram cinco plantas no estádio de maturação "maduro" com dez repetições compostas de um fruto, totalizando 50 frutos. Resultados: o fruto do noni é de formato ovóide, suculento e apresenta várias sementes triangulares de coloração vermelha. Considerando a polpa, ocorre mudança de coloração, passando da cor verde para a amarela esbranquiçada, à medida que o fruto amadurece. De acordo com os resultados obtidos, os estádios apresentam variabilidade para quase todos os caracteres físicos e físico-químicos. Conclusões: de acordo com os resultados obtidos, os frutos de noni "maduro" apresentaram para a massa fresca valor médio de 221,50 g, diâmetro longitudinal e transversal médio de 106,60 e 59,96 mm, respectivamente, altos valores para a relação DL/DT, com média geral de 1,94, firmeza da polpa média de 12,82 N, teor médio de sólidos solúveis de 8,40 °Brix, acidez titulável de 0,28 %, pH de 4,53, relação SS/AT de 34,26 e elevados teores de vitamina C, com valor médio de 177,33 mg.100 g-1 de polpa, fator este de grande importância para a indústria.

Introduction: Noni is a fruit brought to Brazil as raw material with strong commercial appeal due to all its beneficial features and consumption-related benefits. Objective: to make the physical and physicochemical characterization of the "mature" noni fruit in the maturation stage (yellowish white coloration). Methods: Noni fruits were harvested on five plants at Alberto Antônio Farm, located near the city of Trairi, Ceará (Trairi-CE). For the fruit characterization, the following analysis were made: fresh fruit mass (g), longitudinal and transverse length (mm), DL/DT, firmness (N), vitamin C (mg.100 g-1 of pulp), soluble solids (° Brix), titratable acidity (%), pH and SS/AT ratio. A completely randomized approach was adopted, and the treatments consisted of five plants in "mature" stage with ten repetitions, composed by one fruit, for a total of 50 fruits. Results: Noni fruit is ovoid, succulent, and juicy, and presents several triangular red seeds. The pulp's color changed from green to yellowish white according to the ripeness of the fruits. As to the obtained results, the stages showed variability in almost all the physical and physical-chemical characters. Conclusions: "mature" noni fruit presented fresh average weight of 221,50 g, longitudinal and transverse diameter of 106,60 and 59,96 mm, respectively, high values for the DL/DT ratio, with overall average of 1,94; pulp firmness average of 12,82 N, soluble solids content average of 8,40 °Brix, titratable acidity of 0,28 %, pH of 4.53; SS/AT ratio of 34,26 and high levels of vitamin C, with pulp average of 177,33 mg.100 g-1, which is a feature of great importance for the industry.

Introducción: el noni es una fruta que llegó a Brasil como una materia prima con fuerte atractivo comercial, por todas las características beneficiosas asignadas y los beneficios relacionados con su consumo. Objetivo: realizar la caracterización física y fisicoquímica de las frutas del noni en etapa de maduración ("maduran" amarillo blanquecino). Métodos: las frutas de noni se cosecharon de 5 plantas que se encontraban en la granja Alberto Antônio, situada cerca de la ciudad de Trairi-CE. Para la caracterización de la fruta se hicieron los análisis siguientes: pasta fresca de fruto (g), medidas longitudinales (mm) y transversales (mm), DL/DT, firmeza (N), vitamina C (mg 100 g-1 de la pulpa), sólidos solubles (° Brix), acidez titulable (%), (pH) y SS/AT. Se tomó un diseño completamente al azar, los tratamientos fueron 5 plantas en etapa "madura" con 10 repeticiones, compuestos de una fruta, un total de 50 frutos. Resultados: la fruta de noni es ovoide, jugosa y presenta varias semillas triangulares de color rojo. En la pulpa se produce un cambio de color, pasando de verde a un color amarillo blanquecino como la fruta madura. Según los resultados, los estadios tienen variabilidad para casi todos los caracteres físicos y fisicoquímicos. Conclusiones: la fruta de noni "madura" presenta 221,50 g masa promedio fresca, diámetro longitudinal y transversal de 106,60 y 59,96 mm, respectivamente; valores altos para el DL/DT, con un promedio general de 1,94, firmeza de pulpa un promedio de 12,82 N, contenido de sólidos solubles de 8,40 ° Brix, acidez titulable de 0,28 %, pH de 4,53, 34,26 SS/AT; y altos niveles de vitamina C, con un promedio de pulpa de 177,33 mg.100 g-1, factor de gran importancia para la industria.