Composición química y actividad antibacteriana del aceite esencial de Laureliopsis philippiana (Looser)

Laureliopsis philippiana (Looser) es una especie  siempre verde nativa de Chile y Argentina usado en medicina tradicional. En  este estudio se determinó tanto la composición química del aceite esencial obtenido a partir de hojas de esta especie, así como su actividad  antibacterial in vitro contra Escherichia coli, Enterobacter aerogenes, Staphylococcus epidermidis and Staphylococcus aureus. El análisis  químico por GC-MS permitió la identificación de 19 compuestos, representando el 98,8% de la composición del aceite. Monoterpenos  oxigenados, eucaliptol y linalol fueron los mayores constituyentes del aceite con un 37,4%  y 32,3%  respectivamente. Para evaluar la  actividad antibacteriana se utilizaron los métodos de difusión en agar y dilución en caldo. El aceite esencial muestra actividad inhibitoria  contra las bacterias Gram (-) y Gram (+) evaluadas, mientras que linalol por si solo logra un efecto inhibitorio comparable con el aceite  esencial contra E. aerogenes y S. epidermidis mientras que el  linalol por si solo, logra un efecto inhibitorio contra E. aerogenes y S.  epidermidis comparable al del aceite esencial

Estudio de la estabilidad de aceite comestible de girasol coloreado con pigmentos clorofílicos y con adición de oleorresina de orégano (Origanum vulgare L.) durante el almacenamiento en oscuridad.

Sunflower (Helianthus annuus L.) oil was coloured with pigments extracted from green leaves. Different amounts (0, 200, 400, 600, and 800 ppm) of oleoresin extracted from oregano (Origanum vulgare L.) as antioxidant, were added to the coloured oil. As controls, coloured oil without oleoresin (A.C.) and pure oil (A.P.) were used. The samples were stored at room temperature (10-20 ºC) in the dark for up to six months. During this time the oxidation of oleic acid, linoleic acid, peroxides index and the chlorophyll pigments were analized and the colour of the oil was determined. During the first month, only the ratio of chlorophyll to pheophytin changed, whereas all the other parameters stayed constant, independently to the amount of antioxidant added. Since among the treatments A.C. and A.P. not significant differences (p >0,05) were found, for oleic and linoleic methyl ester acids and peroxides index, it can be concluded that the edible, coloured sunflower oil shows an equivalent stability to the pure oil, when stored at darkness for three or six month. There was not observed an evident antioxidant action with the added oregano oleorresin to the coloured oil.Se estudió la estabilidad de aceite comestible de girasol (Helianthus annuus L.) de marca comercial sin antioxidantes, coloreado con pigmentos obtenidos de hojas verdes. Al aceite coloreado se adicionó oleorresina de orégano, como antioxidante, en cuatro concentraciones diferentes (200, 400, 600 y 800 ppm). Como controles, se utilizó aceite coloreado sin oleorresina (A.C.) y aceite puro (A.P.). Se almacenó en oscuridad y temperatura ambiente (10-20 ºC) por seis meses. Se evaluó la oxidación de lípidos (ésteres metílicos de ácidos oleico y linoleico e índice de peróxidos), pigmentos clorofílicos y color.El total de los pigmentos clorofilicos adicionados a las muestras de aceite comestible de girasol se mantuvo estable durante los tres primeros meses, evidenciándose sólo cambios en la proporción de clorofila a,b y feofitina a,b en el primer mes. Dado que no se encontraron diferencias significativas (p >0,05) entre los tratamientos A.P. y A.C., para ésteres metílicos de ácidos oleico y linoleico e índice de peróxidos, se podría concluir que el aceite comestible de girasol coloreado muestra una estabilidad equivalente al aceite puro, cuando es almacenado en oscuridad por tres o seis meses. No se observó un claro efecto de la acción antioxidante que tendría la oleorresina de orégano adicionada al aceite coloreado

Influence of murta (Ugni molinae turcz) powder on the frankfurters quality

Frankfurters are one of the most demanded meat products in the world due to their low cost and good taste. However, they contain up to 30% animal fat, which is negative for the consumer’s health. Moreover, high-fat contents could also decrease frankfurter sensory properties, since it accelerates the rancidity of the products. This fact is highly dependent on the fatty acids composition since the unsaturation promotes oxidative reactions. Currently, strategies have been developed to replace animal fat with vegetable oils or the inclusion of new raw materials. The murta (Ugni molinae Turcz), an endemic plant in Chile, is a specie that contains high levels of flavonoids in its fruits and has a pleasant flavor, as well as a sweet and floral aroma. However, the effect of the addition of these fruits in the formulation of meat products has been scarcely studied. The present study aims to reduce the use of synthetic additives using natural ones (murta powder). Therefore, this research evaluated the influence of the inclusion of murta on the chemical, sensory, and instrumental parameters of traditional frankfurters. Three batches of frankfurters were manufactured: control sausages without additives (T0); samples with chemical antioxidant (T1); and with murta fruit powder (T2). The chemical composition, physicochemical parameters and sensory properties were determined. Frankfurters made with murta (T2) presented middle values in energy, moisture and sodium compared with control. Also, the reformulated sausages (T2) presented the lowest water holding capacity, redness (a*) and yellowness and the highest values of fat and carbohydrates. Regarding fatty acids content, the most important changes were observed in the C18:0 and C14:0 (T2 presented the lowest values) and C18:2n-6 (T2 had the highest values), but minimal differences were observed in the total SFA, MUFA and PUFA content. Cholesterol content from T2 were similar to the control samples, and T1 presented the highest values. Although these differences, both chemical and nutritional quality of all frankfurters manufactured in the present study were very similar among treatments. Finally, according to the sensory analysis, T2 presented better acceptability and sensory characteristics compared with the other treatments (p ≤ 0.05). Therefore, the inclusion of murta in the production of frankfurters could be a strategy to improve the sensory characteristics of this product with minimal changes in chemical and nutritional properties. However, the effect of murta on oxidative stability and frankfurter shelf-life should be studied in depth in future research.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Influence of Murta (Ugni molinae Turcz) Powder on the Frankfurters Quality

Frankfurters are one of the most demanded meat products in the world due to their low cost and good taste. However, they contain up to 30% animal fat, which is negative for the consumer’s health. Moreover, high-fat contents could also decrease frankfurter sensory properties, since it accelerates the rancidity of the products. This fact is highly dependent on the fatty acids composition since the unsaturation promotes oxidative reactions. Currently, strategies have been developed to replace animal fat with vegetable oils or the inclusion of new raw materials. The murta (Ugni molinae Turcz), an endemic plant in Chile, is a specie that contains high levels of flavonoids in its fruits and has a pleasant flavor, as well as a sweet and floral aroma. However, the effect of the addition of these fruits in the formulation of meat products has been scarcely studied. The present study aims to reduce the use of synthetic additives using natural ones (murta powder). Therefore, this research evaluated the influence of the inclusion of murta on the chemical, sensory, and instrumental parameters of traditional frankfurters. Three batches of frankfurters were manufactured: control sausages without additives (T0); samples with chemical antioxidant (T1); and with murta fruit powder (T2). The chemical composition, physicochemical parameters and sensory properties were determined. Frankfurters made with murta (T2) presented middle values in energy, moisture and sodium compared with control. Also, the reformulated sausages (T2) presented the lowest water holding capacity, redness (a*) and yellowness and the highest values of fat and carbohydrates. Regarding fatty acids content, the most important changes were observed in the C18:0 and C14:0 (T2 presented the lowest values) and C18:2n-6 (T2 had the highest values), but minimal differences were observed in the total SFA, MUFA and PUFA content. Cholesterol content from T2 were similar to the control samples, and T1 presented the highest values. Although these differences, both chemical and nutritional quality of all frankfurters manufactured in the present study were very similar among treatments. Finally, according to the sensory analysis, T2 presented better acceptability and sensory characteristics compared with the other treatments (p 0.05). Therefore, the inclusion of murta in the production of frankfurters could be a strategy to improve the sensory characteristics of this product with minimal changes in chemical and nutritional properties. However, the effect of murta on oxidative stability and frankfurter shelf-life should be studied in depth in future research.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Home-Drying Operation Effect on Moisture Content, Electric Energy Consumption, Ascorbic Acid, Total Polyphenol Content, and Color of Sliced “Fuji” Apples

A home dehydrator allows obtaining dried apples that are beneficial to human health, but its operations will affect the chemical and organoleptic quality of this fruit. In this study, the effect of the drying temperature and mass load of sliced fresh “Fuji” apples in a home dehydrator was evaluated with regard to moisture content, electric energy consumption, ascorbic acid, total polyphenol content, and color of the dried fruit. Fresh “Fuji” apples were cut to obtain a uniform slice with a thickness of 4 mm and diameter from 60 to 75 mm. A home dehydrator was operated at 50 and 70°C (nominal temperatures), with a total sliced apple load of 250 and 500 g, uniformly distributed in five trays. Drying was carried out for 7 hours, and every hour, the trays were rotated, changing their position from the top to the bottom. Only the middle tray was always kept in the same position. As result, the level of nominal temperature (50/70°C) was not reached for any of the trays, regardless of the mass load (250/500 g) in the home dehydrator. The temperature average for fruits dried in trays of the home dehydrator that were rotated (top and bottom) and kept in the same position (middle) did not differ (p>0.05) among them. At the end of drying, the apple treatment at 50°C/250 g, 50°C/500 g, 70°C/250 g, and 70°C/500 g reached 23.1, 26.2, 4.3, and 4.5% (w.b.), respectively. The drying conditions at nominal 50°C favored the quality of the dried sliced apples with regard to ascorbic acid and total polyphenol content; however, the treatment at nominal 70°C produced less variation in color with respect to the fresh fruit. The home dehydrator allowed obtaining sliced dried “Fuji” apples that adequately preserve the ascorbic acid, total polyphenol, and color with respect to the fresh fruit

Stearoyl CoA desaturase and fatty acid synthase gene polymorphisms and milk fatty acid composition in Chilean Black Friesian cows

Background: in recent years, market attention has increasingly focused on improving the quality of dairy products. Therefore, animal selection for healthier milk fatty acid composition are therefore of interest. Objective: the aim of this study was to identify whether two polymorphisms (c.878T>C in the SCD gene and g.17924A>G in the FASN gene) are related with the fatty acid composition of milk. Methods: individual milk samples were collected from 50 Chilean Black Friesian cows. Fatty acids (FA) from each milk sample were extracted, analyzed, and quantified (mg FA/g of milk) by gas chromatography. The genotype of each sample was also determined using PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism). Results: milk from cows with a c.878CC genotype in the SCD gene exhibited a greater content of C14:1, C17:1, C18:1n9t, C18:1n9c, and total monounsaturated fatty acids (MUFA), as well as a higher 14:1/14 ratio than other SCD genotypes. In addition, considering the importance of the predominant isomer of conjugated linoleic acid for human diet, we identified a higher content of cis-9, trans-11 conjugated linoleic acid in milk samples from animals that had the c.878CC genotype. For the FASN gene, cows with the g.17924GG genotype presented high contents of C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c, and MUFA. Conclusion: therefore, these polymorphisms could be useful genetic markers for studying the fatty acid composition of dairy milk.Antecedentes: nos últimos anos, o mercado fornecedor de laticínios tem-se voltado ao melhoramento da qualidade dos seus produtos. Por conseguinte, é de interesse a seleção de animais que apresentem uma composição de ácidos graxos mais saudáveis no seu leite. Objetivo: o objetivo principal deste estudo foi identificar dois polimorfismos (c.878T>C no gene SCD e g.17924A>G no gene FASN) e sua associação com a composição de ácidos graxos do leite. Métodos: as amostras de leite foram coletadas de 50 vacas Frison Preto Chileno. Os ácidos graxos (FA) de cada amostra de leite foram extraídos, analisados e quantificados (mg FA/g leite) por cromatografia gasosa. O genótipo de cada amostra foi determinado pela reação de PCR-RFLP (Reação em cadeia de polimerase - polimorfismo de comprimento dos fragmentos de restrição). Resultados: os animais com o genótipo c.878CC no gene SCD têm um teor mais elevado de C14:1, C17:1, C18:1n9t, C18:1n9c e do total de ácidos graxos monoinsaturados (AGM), além de níveis mais elevados de 14:1/14 que outros genótipos SCD. Além disto, devido à importância na dieta humana do isômero predominante do ácido linoléico conjugado (CLA), identificou-se um maior teor de cis-9, trans-11 CLA nas amostras de leite de animais que tinham o genótipo c.878CC. Para o gene FASN, as vacas com o genótipo g.17924GG tinham um teor mais elevado de C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c e AGM. Conclusão: estes polimorfismos poderiam ser usados como marcadores genéticos para o estudo da composição de ácidos graxos do leite de vaca.Antecedentes: en los últimos años, la atención del mercado se ha centrado cada vez más en mejorar la calidad los productos lácteos. Por lo tanto, la selección de animales con una composición de ácidos grasos de leche más saludable es de interés. Objetivo: el principal objetivo de este estudio fue identificar dos polimorfismos (c.878T>C en el gen SCD y g.17924A>G en el gen FASN) y su relación con la composición de ácidos grasos de leche. Métodos: muestras individuales de leche fueron recolectadas de 50 vacas Frison Negro Chileno. Los ácidos grasos (FA) de cada muestra de leche fueron extraídos, analizados y cuantificados (mg FA/g leche) por cromatografía de gases. El genotipo de cada muestra se determinó mediante la técnica PCR-RFLP (reacción en cadena de la polimerasa - polimorfismo de longitud de fragmentos de restricción). Resultados: los animales con el genotipo c.878CC en el gen SCD presentaron un mayor contenido de C14:1, C17:1, C18:1n9t, C18:1n9c y total de ácidos grasos monoinsaturados (MUFA), así como elevados índices de 14:1/14 que otros genotipos SCD. Además, debido a la importancia en la dieta humana del isómero predominante de ácido linoleico conjugado (CLA), hemos identificado un mayor contenido de cis-9, trans-11 CLA en muestras de leche de animales que poseen el genotipo c.878CC. Para el gen FASN, vacas con el genotipo g.17924GG presentaron un mayor contenido de C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c y contenido total de ácidos grasos monoinsaturados (MUFA). Conclusión: por lo tanto, estos polimorfismos podrían servir como marcadores genéticos para el estudio de la composición de ácidos grasos en la leche de vaca

Stearoyl CoA desaturase and fatty acid synthase gene polymorphisms and milk fatty acid composition in Chilean Black Friesian cows

Background: in recent years, market attention has increasingly focused on improving the quality of dairy products. Therefore, animal selection for healthier milk fatty acid composition are therefore of interest. Objective: the aim of this study was to identify whether two polymorphisms (c.878T>C in the SCD gene and g.17924A>G in the FASN gene) are related with the fatty acid composition of milk. Methods: individual milk samples were collected from 50 Chilean Black Friesian cows. Fatty acids (FA) from each milk sample were extracted, analyzed, and quantified (mg FA/g of milk) by gas chromatography. The genotype of each sample was also determined using PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism). Results: milk from cows with a c.878CC genotype in the SCD gene exhibited a greater content of C14:1, C17:1, C18:1n9t, C18:1n9c, and total monounsaturated fatty acids (MUFA), as well as a higher 14:1/14 ratio than other SCD genotypes. In addition, considering the importance of the predominant isomer of conjugated linoleic acid for human diet, we identified a higher content of cis-9, trans-11 conjugated linoleic acid in milk samples from animals that had the c.878CC genotype. For the FASN gene, cows with the g.17924GG genotype presented high contents of C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c, and MUFA. Conclusion: therefore, these polymorphisms could be useful genetic markers for studying the fatty acid composition of dairy milk

Effect of immersion solutions on shelf-life of minimally processed lettuce

Abstract Prior to detailed quality and physiology evaluations, different immersion solutions (SIs) were analysed by means of a nontrained sensory panel. Each SI (calcium chloride, pectin, potassium sorbate, garlic extract and citric acid) was analysed at three concentrations. Based on at least 70% acceptance, the best mixed SI (Po0:05) was determined to be 2 g/L citric acid, 1 g/L calcium chloride and 250 g/L garlic extract (SI). The control treatment was washed only with 0.05 g/L active chlorine. Treated lettuce was stored at 5 C in darkness in sealed polypropylene bags, for 9 days. Some senescence indicators (weight loss, colour), certain enzymes related to colour (chlorophyllase and polyphenoloxidase), and a nutrient (ascorbic acid), were measured during storage. SI showed a positive effect on shelf-life of minimally processed lettuce, controlling enzymatic browning, chlorophyllase activity and weight loss. The microorganisms growth was not significantly controlled, but the fact that the organoleptic results of SI-treated lettuce showed about 80% acceptability during 9 days of storage, suggests that some slight modifications on SI could be the basis of a promising formula for minimally processed lettuce

Antioxidant activity and sensory analysis of murtilla (Ugni molinae Turcz.) fruit extracts in an oil model system

Actividad antioxidante y evaluación sensorial de extractos de frutos de murtilla (Ugni molinae Turcz.) en un sistema modelo aceitoso. Se analizó la actividad antioxidante de extractos de una fruta chilena en un sistema modelo aceitoso y se determinó el efecto sobre las características organolépticas. Se utilizaron extractos hidroalcohólicos de frutos de murtilla (Ugni molinae Turcz.) silvestre y del genotipo 14-4, y se aplicó la Metodología de Superficie de Respuesta. Las condiciones óptimas para obtener extractos con altos contenidos de fenoles totales fueron 49,5% (v/v) de etanol a 30 °C, lo que produjo 18,39 y 26,14 mg AGE g−1 materia seca, respectivamente. Los extractos optimizados se añadieron a un sistema modelo aceitoso y se evaluaron a través de una prueba de estabilidad en horno Schaal. Después de 96 horas, los extractos de frutos silvestre (150 mg·kg−1 aceite) y genotipo 14-4 (200 mg·kg−1 aceite) mostraron una capacidad antioxidante similar al TBHQ (200 mg·kg−1 aceite) en términos de índice de peróxido y respecto a las características organolépticas. Se concluye que los extractos de frutos de murtilla son una fuente natural de antioxidantes para la protección de los alimentos lipídicos, tales como el aceite de soja.An oil model system was used to analyze the antioxidant activity of Chilean fruit extracts and to determine their odor sensory effect. Hydroalcoholic extracts from wild and 14-4 genotype murtilla (Ugni molinae Turcz.) fruit were assessed by the Response Surface Methodology. The optimal conditions for producing high total phenolic-content extracts were 49.5% (v/v) ethanol at 30 ºC, which yielded 18.39 and 26.14 mg GAE·g−1 dry matter, respectively. The optimized extracts were added to a lipid model system and evaluated via the Schaal Oven Test. After 96 hours, 150 and 200 mg·kg−1 oil of the wild and 14-4 genotype extracts, respectively, showed an antioxidant capacity similar to TBHQ (200 mg·kg−1 oil) in terms of peroxide values and odor. Thus, murtilla fruit extracts are a natural source of antioxidants for protecting lipidic foods, such as soybean oil