Effectiveness Comparison of Polysaccharides, Proteins, and Lipids as Composite Edible Coatings on the Quality of Food Products / Comparación de la Efectividad de Polisacáridos, Proteínas y Lípidos como Recubrimientos Compuestos Comestibles en la Calidad de los Productos Alimenticios

Background: This research was motivated by the complaints of tomato farmers about their crops that quickly rotted before being sold, as well as the many research results (raw materials and methods) that edible coating films could not be applied optimally. Objectives: The research was a practical recommendation by comparing the effectiveness of raw materials (polysaccharides, proteins, and lipids) with the dipping and spray methods. Materials and methods used in the comparison process were the application of Structural Equation Modeling (SEM) with the Partial Least Square (PLS) approach. Results: Dipping has a strong effect (f2 ≥ 0.35; p<0.05), while spray had a moderate effect (f2: 0.15-0.35; p<0.05). Thus, the role of dipping as a mediator was more dominant than spray. Compared to proteins and lipids, polysaccharides had the best effectiveness (ß:0.460-0.584; f2: 0.15-0.35; p<0.05). Conclusion: the three ingredients improved the quality of tomatoes, and the dipping method was easier to apply by farmers than the spray method, which had many obstacles in its application

Antecedentes: esta investigación está motivada por las quejas de los productores de tomate sobre sus cultivos que se pudren rápidamente antes de ser vendidos, así como por los muchos resultados de la investigación (materias primas y métodos) de que las películas de recubrimiento comestibles no se pudieron aplicar de manera óptima. Objetivos: La investigación consiste en recomendaciones prácticas mediante la comparación de la eficacia de las materias primas (polisacáridos, proteínas y lípidos) con los métodos de inmersión y aspersión. Métodos: El método utilizado en el proceso de comparación es la aplicación del modelo de ecuaciones estructurales (SEM) con el enfoque de mínimos cuadrados parciales (PLS). Resultados: La inmersión tiene un efecto fuerte (f2 ≥ 0,35; p<0,05), mientras que la pulverización tiene un efecto moderado (f2: 0,15-0,35; p<0,05). Por lo tanto, el papel de la inmersión como mediador es más dominante que el del rociado. Los polisacáridos tienen la mejor eficacia (ß:0,460-0,584; f2: 0,15-0,35; p<0,05) en comparación con las proteínas y los lípidos. Conclusión: es que los tres ingredientes pueden mejorar la calidad de los tomates, y el método de inmersión es más fácil de aplicar por los agricultores que el método de aspersión, que tiene muchos obstáculos en su aplicación

INCREMENTO EN LA VIDA ÚTIL POST COSECHA DEL AGUACATE (Persea americana) UTILIZANDO RECUBRIMIENTOS A BASE DE GOMA GELANA

El aguacate es uno de los frutos de importancia económica en Colombia que presenta pérdidas en post cosecha. El objetivo de esta investigación fue evaluar el efecto de un recubrimiento comestible a base de gelana de alto (GAA) y bajo acilo (GBA), sobre la calidad post cosecha del aguacate (Persea americana cv. "Hass"), almacenado durante nueve semanas. Para la elaboración de los recubrimientos, se utilizó un diseño factorial 2³, donde los factores fueron las concentraciones de GAA (0,30 y 0,60% p/v), GBA (0,30 y 0,60% p/v) y glicerol (GLI) (8,0 y 12% v/v); como agente antimicrobiano, se utilizó extracto acuoso de Toronjil (Melissa officinalis L), por ser un aditivo natural. Se evaluaron propiedades, como la firmeza, la pérdida de humedad, el pH y los sólidos solubles totales (SST), durante almacenamiento. Finalmente, para la estimación del periodo de vida útil, se empleó la ecuación de Monod Hinshelwood, previo modelado de los datos, con ayuda de la ecuación de Baranyi y Roberts. Los resultados indicaron que la aplicación de recubrimientos comestibles de goma gelana, conteniendo bajas concentraciones de glicerol, disminuye significativamente (P<0,05) la pérdida de firmeza, de humedad, de sólidos solubles y evitan grandes modificaciones del pH, manteniendo la calidad del aguacate, alargando la vida útil.

Avocado is one of the fruits of economic importance in Colombia. However, it presents losses mainly during the post-harvest period. The aim of this research was to evaluate the effect of an edible coating based on high acyl (HAG) and low acyl gellan (LAG) on post-harvest avocado quality (Persea americana cv. "Hass") stored during nine weeks. A factorial design 2³ was employed for the biofilm preparation, where the factors were concentrations of HAG (0.30 and 0.60% w/v), LAG (0.30 and 0.60% w/v) and glycerol (GLY v/v). As antimicrobial aqueous extract of lemon balm (Melissa officinalis L) was used. Properties such as firmness, moisture loss, pH, total soluble solids (TSS) during storage were evaluated. Finally, for the microbiological shelf life estimation the Hinshelwood Monod equation was applied previous data modeling using the Baranyi and Roberts model. The results indicated that the application of edible coatings based on gellan gum containing low concentrations of glycerol reduces the loss of firmness, moisture, soluble solids and prevent large changes in pH, maintaining the quality of avocado and extend its shelf life.

Conservación de mango Tommy Atkins mínimamente procesado mediante la aplicación de un recubrimiento de aloe vera (Aloe barbandensis Miller) / Conservation of minimally processed mango Tommy Atkins by applying an aloe vera (Aloe barbandensis Miller) coating

Antecedentes: El mango es una fruta climatérica que puede ver limitada su comercialización debido a la deficiencia en sistemas de procesamiento y conservación que ocasionan pérdidas poscosecha en la cadena agroindustrial. Los frutos mínimamente procesados y tratados con recubrimientos comestibles representan una alternativa para mitigar la perecibilidad del fruto, conservando sus atributos de calidad y ofreciendo al consumidor un producto de fácil consumo y almacenamiento. Objetivos: Conservar y prolongar la vida útil de mango Tommy Atkins mínimamente procesado con la aplicación de un recubrimiento comestible de Aloe vera, evaluando su efectividad mediante el análisis de parámetros físicos, fisicoquímicos, respiratorios, microbiológicos y sensoriales durante almacenamiento refrigerado. Métodos: El recubrimiento comestible fue preparado con gel mucilaginoso de aloe vera en una Concentración de 50 % P/P en dilución y homogenizado con cera carnauba y glicerol, para luego ser aplicado por inmersión en los frutos previamente cortados y secados en estufa. Se diseñaron cuatro tratamientos experimentales: C, R, PreREC y CA, almacenados en refrigeración durante un periodo de 12 de días, en los que se evaluó parámetros como firmeza, color, porcentaje de pérdida de peso, pH, Brix, acidez (%), tasas respiratorias, conteos microbiológicos y descriptores sensoriales por medio de un perfil de aproximación multidimensional. Los datos fueron procesados mediante ANOVA y por el método de comparaciones múltiples LSD. Resultados: Las muestras tratadas con el recubrimiento (R y PreREC) mostraron un retraso en la pérdida de la firmeza, menores cambios de color, una menor pérdida de peso, un aumento menos acelerado del pH y de °Brix y valores más elevados de acidez con respecto a los tratamientos control. Se lograron tasas bajas de consumo de O2 y una producción controlada de CO2 en comparación a las muestras sin tratar. A nivel microbiológico, el recubrimiento disminuyó el crecimiento de mesófilos, mohos y levaduras; mientras que sensorialmente, descriptores como la firmeza, calidad general, olor y sabor característico mostraron una mayor calificación por parte del panel sensorial. Conclusiones: El recubrimiento permitió conservar por 3 días más las muestras de mango mínimamente procesado respecto a los tratamientos control.

Background: Mango is a climacteric fruit which can limit its marketing due to some deficiencies in processing and preservation systems that cause postharvest losses in the agribusiness and value chain. Minimally processed fruits and edible coatings represent an alternative to decrease the perishability of fruits, preserving its quality attributes and offering to consumers an easy product to use and storage. Objetives: The aim of this study was to conserve and extend the shelf life of minimally processed "Tommy Atkins" mango covered by an edible coating made of aloe vera mucilage, assessing its effectiveness by analyzing physical, physicochemical, respiratory, microbiological and sensory parameters during refrigerated storage. Methods: The edible coating was prepared with aloe vera, which is a mucilaginous gel, in a concentration of 50% w/w in dilution and homogenized with carnauba wax and glycerol. Then aloe vera was applied by immersion in the pre-cut fruits and dried in stove. Four experimental treatments were designed: C, R, PreREC and CA, stored under refrigeration for a period of 12 days, in which parameters such as strength, color, percentage weight loss, pH, Brix, acidity (%), respiratory rates, microbiological counts, and sensory descriptors were evaluated by a multidimensional approach profile. Data were analyzed using ANOVA and the LSD multiple comparison method. Results: Samples treated with the edible coating (R y PreREC) showed a delay in the loss of firmness, less color changes, less loss of weight, a less increase in pH and Brix values, and a higher acidity compared to the control treatments. Low rates of O2 consumption and controlled CO2 production compared to untreated samples were achieved. Coating decreased the growth of mesophilic, molds and yeasts; while sensory descriptors as firmness, overall quality, characteristic odor and taste showed a higher rating by the sensory panel. Conclusions: Edible coating made of aloe vera gel allowed to keep for 3 more days samples of minimally processed mango compared to control treatments.

Antimicrobial and aromatic edible coating on fresh-cut pineapple preservation / Revestimento comestível antimicrobiano e aromático na conservação de abacaxi minimamente processado

The present research aimed to develop an edible coating incorporated with mint essential oil, evaluate its effectiveness in inhibiting in vitro microbial development, and improve both quality and shelf-life of fresh-cut pineapple. Mint essential oil-containing edible coatings showed in vitro antimicrobial efficiency against Escherichia coli and Salmonella Enteritidis. Titratable acidity, pH, and texture were not affected (P>0.05) by coating or storage time. Mass loss was not higher than 1.0% after the 6th day of storage. No effect of storage time and coating on total soluble solids was observed. Mint essential oil-containing coatings inhibited the growth of yeasts and molds in fresh-cut pineapple. Compared to uncoated and control-coated samples, mint essential oil-containing coatings lessened psychrotrophic bacteria counts throughout storage. Counts of thermotolerant coliforms were not higher than 3.0MPN·g-1 in all treatments, whereas no Salmonella sp. was detected during the 6-day storage. Mint essential oil provided a strong flavor to the fruit, as shown by sensory evaluations.

O objetivo deste trabalho foi desenvolver um revestimento comestível incorporado com óleo essencial de hortelã, bem como avaliar sua eficiência antimicrobiana in vitro e em abacaxi minimamente processado. Revestimentos contendo óleo essencial de hortelã mostraram eficiência antimicrobiana in vitro contra Escherichia coli e Salmonella Enteritidis. O pH, a acidez titulável e a textura não foram afetadas (P>0.05) pelos tratamentos durante o armazenamento. A perda de massa dos abacaxis de todos os tratamentos não ultrapassou 1.0% após 6 dias de armazenamento. O tempo e os diferentes revestimentos não afetaram (P>0,05) o teor de sólidos solúveis totais dos abacaxis. Revestimentos contendo óleo essencial de hortelã foram capazes de inibir o crescimento de fungos e leveduras em abacaxi minimamente processado, quando comparado aos frutos sem revestimento e com revestimento controle. Frutos com revestimento contendo óleo essencial de hortelã apresentaram menor contagem de psicrotróficos no final do armazenamento. A contagem de coliformes termotolerantes foi menor que 3.0NMP·g-1 para todos os tratamentos e não foi detectada presença de Salmonella sp. durante o período de armazenamento. A presença de óleo essencial de hortelã conferiu forte sabor aos abacaxis.

Métodos de conservação aplicados a melão minimamente processado / Conservation methods applied to fresh-cut melon

O objetivo desta revisão é apresentar alguns métodos de conservação que podem ser utilizados para prolongar a vida útil do melão minimamente processado. Dentre os métodos, serão abordados revestimento comestível, irradiação, antimicrobianos naturais, antioxidantes, agentes de firmeza, atmosfera modificada, branqueamento, luz ultravioleta e alta pressão. Dependendo do método pode haver redução das alterações associadas ao processo mínimo do melão, como a perda de água, alteração da cor e firmeza, alteração do metabolismo e crescimento de micro-organismos, sendo o resultado muitas vezes dependente da cultivar do melão utilizado.

The objective of this review is to present some conservation methods that can be used to prolong the life of fresh-cut melon. Among the methods, edible coating, irradiation, natural antimicrobials, antioxidants, firmness agent, modified atmosphere, whitening, ultraviolet light and high pressure will be discussed. Depending on the method, the changes associated to minimum process of melon, such as water loss, change in color and firmness, change in the metabolism and growth of micro-organisms can be reduced and the result is often dependent on the melon cultivar used.

El glaseado incorporando hidrocoloides como alternativa en el empaque de lomo de atún (Thunnus thynnus) congelado y almacenado a -10ºC / Tuna (Thunnus thynnus) glazed with hydrocolloids as alternative of edible coatings and storaged at -10ºC

Numerosos estudios han sido enfocados a los ingredientes naturales para mantener la calidad y la vida útil de los alimentos. Los ingredientes biodegradables, tales como hidrocoloides y proteínas pueden ser utilizados para cubrir filetes de pescado con el objetivo de suprimir los cambios de calidad durante el almacenamiento en congelación. En la actualidad se han venido desarrollando empaques comestibles, como el glaseado con hidrocoloides, (gelatina, carragenina), que además de cumplir sus funciones como película protectora del alimento, son económicos, pueden ser ingeridos por el consumidor sin riesgo de toxicidad, ayudan a preservar las características organolépticas del producto, proporcionar características nutricionales y, por ser biodegradables contribuyen a la conservación del ambiente. El objetivo del presente estudio fue evaluar la incorporación de hidrocoloides al glaseado de lomos de atún como una alternativa de empaque. Cortes de atún fueron glaseados incorporándole soluciones de carragenina 0,05, y 0,15%, y gelatina al 0,5, 1%. Los cortes fueron de 15 cm3, congelados a -30ºC y glaseados con los tratamientos mencionados sumergiéndose la muestra de atún en las soluciones a 0 ºC por 30 segundos y luego almacenados a -10ºC por 0, 15 y 30 días. Los resultados del análisis proximal, las proteínas solubles, rancidez oxidativa, y color mostraron que todas las muestras glaseadas con hidrocoloides mantienen sus características y protege al lomo de atún ante la pérdida de humedad y retrasa la degradación de las proteínas. De igual manera la carragenina mostró un mejor desempeño como empaque a concentraciones de 0,05% en comparación con la gelatina.

Numerous studies have been focused to natural ingredients to maintain the quality and shell life of foods. Edibles coating, biodegradable ingredients, such as hydrocolloids and proteins can be used for coating fish with the purpose to suppress changes of quality during frozen storage. At the present time several developing of edibles packing, like glaze using hydrocolloids, (gelatin, carrageen, starch), that besides acts as protective film for food, they are economic, can be ingested by the consumer without toxicity risk, help to preserve organoleptics and nutritional characteristics of the product and, being biodegradable they contribute to the conservation of the atmosphere. The objective of the present study was to evaluate the incorporation of hydrocolloids in the glazing tuna process as alternative of packing, to enhance its physical and chemical characteristics. Samples of tuna was glazed incorporating to its solutions of carrageen at 0.05, 0,1 and 0.15%, and gelatin at 0.5, 1%. The samples were shaped as square (15 cm3), frozen al -30ºC and glazed incorporating hydrocolloids submerging the sample its solutions at 0 ºC by 30 seconds and storage at -10ºC by 0, 15 and 30 days. Proximal analysis results, soluble proteins, TBA, and color showed that all the samples glazed with hydrocolloids decrease deterioration of the tuna products respect to samples glazed without hydrocolloids; concluding that glazing adding hydrocolloids protects tuna for loss humidity and delays degradation of proteins. Moreover, carrageen shows to a better performance at the concentrations of 0.05% compared with the gelatin and the starch.

Revestimento ativo de amido na conservação pós-colheita de pera Williams minimamente processada / Starch-based edible coating on extending shelf life of fresh-cut pear

A pera é uma das frutas de clima temperado mais consumidas no Brasil, no entanto sua conservação é limitada devido ao seu escurecimento quando sofre danos ou tratamentos físicos. Os revestimentos comestíveis interagem favoravelmente com o alimento, aumentando sua vida de prateleira. Este trabalho objetivou avaliar a ação de revestimento de amido adicionado de lactato de cálcio e L-cisteína na inibição do escurecimento enzimático, na redução do crescimento de psicrotrófilos e enterobactérias e na manutenção da textura. As peras fatiadas foram cobertas com revestimentos comestíveis à base de amido incorporados com cisteína e lactato de cálcio, exceto o controle - sem revestimento (C). Os tratamentos foram: apenas revestimento (T1); 2,0 por cento lactato de cálcio e 1,0 por cento L-cisteína (T2) e 2,0 por cento lactato de cálcio e 1,5 por cento L-cisteína (T3). As amostragens foram feitas nos tempos zero, dois, quatro e seis dias. As amostras foram mantidas sob refrigeração (7°C±2°C). As peras submetidas aos tratamentos T2 e T3 apresentaram-se significativamente mais firmes (P<0,05) que as dos tratamentos C e T1. A ação da cisteína sobre a inibição do escurecimento enzimático foi observada nos tratamentos T2 e T3, que não apresentaram diferença significativa (P≥0,05) entre si para os valores de ∆E, no entanto esses valores foram significativamente menores em relação ao controle. No tempo 6, a redução decimal na contagem de psicrotrófilos chegou a 3,03 e 2,43 para T3 e T2, em comparação com o controle. A contagem de enterobactérias apresentou comportamento semelhante, sendo o valor da redução de 3,16 e 3,05 para T2 e T3 em relação ao controle. Verificou-se que a vida de prateleira de pera minimamente processada pode ser mantida por mais tempo com o uso desse revestimento.

Pear is one of the most consumed temperate fruits in Brazil; however their conservation is limited due to browning when it suffers injuries or physical treatments. The edibles coating interact with the food positively extending its shelf life. This research aimed to evaluate the action of starch edible coating incorporated with calcium lactate and L-cysteine on enzymatic browning inhibition, on psychrotrophs and enterobacteriaceae growing reduction and on firmness maintenance. The sliced pears were coated with starch edible coating incorporated with L-cysteine and calcium lactate, except control, without coating (C). The treatment were: only coating (T1); 2,0 percent calcium lactate and 1,0 percent L-cysteine (T2); 2,0 percent calcium lactate and 1,5 percent L-cysteine (T3). The samples were taken at 0, 2, 4 and 6 days. Pears were keeped under refrigeration (7°C±2°C). Pears submitted to treatments T2 and T3 show significantly more firms (P<0,05) compared to treatments C and T1. Cysteine action over enzymatic browning inhibition was observed in treatments T2 and T3 which do not differed significantly each other (P≥0,05) to ∆E values however these were significantly lower than control (C). At time 6, decimal reduction on psychrotrophs counting reached 3,03 and 2,43 to T3 e T2 compared to control. Enterobacteriaceae counting showed similar behavior where the reduction values were 3,16 and 3,05 to T2 e T3 compared to control. It was verified that using the studied edible coating on fresh cut pear can extend its shelf life.

Caracterização química e bioquímica de goiabas armazenadas sob refrigeração e atmosfera modificada / Chemical and biochemical caracterization of guavas stored under refrigeration and modified atmosphere

O presente trabalho objetivou avaliar o uso de biofilmes de fécula de mandioca na manutenção da qualidade pós-colheita de goiabas 'Pedro Sato'. As frutas foram imersas nas concentrações de 2, 3 e 4 por cento de fécula de mandioca e armazenadas sob refrigeração (9±1ºC e 90±5 por cento UR), durante 20 dias. O biofilme, nas concentrações de 3 e 4 por cento, de fécula de mandioca foi efetivo em retardar o amadurecimento de goiabas proporcionando maior teor de açúcares não-redutores e de vitamina C, menor teor de açúcares totais, açúcares redutores, pectina solúvel, percentual de solubilização e menor atividade de pectinametilesterase e poligalacturonase. A aplicação de biofilme de fécula de mandioca, na superfície de goiabas (Psidium guajava L.), apresentou-se como uma alternativa viável à sua conservação.

The objective of the present work was to evaluate the use of cassava starch biofilms in the maintenance postharvest quality of guavas 'Pedro Sato'. The fruits were soakked in the concentrations of 2, 3 and 4 percent of cassava starch and stored under refrigeration (9±1º C and 90±5 percent RH) for 20 days. The biofilm at the concentration of 3 and 4 percent of cassava starch was more effective in delaying the ripening of guavas promoting higher levels of non-reducing sugars and vitamin C content and lower concentation of total and reducing sugars, soluble pectin content, percentage of solubilization, pectinmetylesterase and polygalacturonase activity. Application of biofilms on to guavas fruit (Psidium guajava L.) surface presents itself as a viable alternative in their conservation.