Impacto de diferentes niveles de nisina como agente bioconservador en la calidad química, sensorial y microbiológica de filetes de lubina (Dicentrarchus labrax) envasados al vacío y almacenados a 4 ± 2 °C.

Nisin is produced by Lactococcus lactis subsp. lactis and is also known as an antimicrobial agent especially effective against gram-positive bacteria. It has long been used as a preservative in foods and beverages and is generally regarded as safe (GRAS). In the present work, the effects of different concentrations of nisin (0.2, 0.4 and 0.8%) on the sensory, chemical and microbiological quality and shelf-life of vacuum-packed sea bass (Dicentrarchus labrax) fillets were investigated during chilled (4 ± 2 °C) storage. The sensory points for raw and cooked fillets increased with time during the storage period (p < 0.05). The control group, with scores of 9.08, was rejected by panelists on day 12; whereas nisin-treated groups were rejected on day 14 with scores ranging from 9.00-9.17 score. As a result of chemical analyses, lower values (p < 0.05) were obtained from the nisin groups with low oxidative rancidity. Moreover, nisin inhibited microbial growth, which shows antimicrobial activity. Consequently, it was concluded that the application of nisin (especially 0.8%) preserved the organoleptic quality and extended the shelf-life of sea bass fillets.La nisina es producida por Lactococcus lactis subsp. lactis y conocida como agente antimicrobiano, especialmente contra las bacterias grampositivas. Se ha utilizado como conservante en alimentos y bebidas durante mucho tiempo y generalmente se considera seguro (GRAS). En el presente trabajo, se investigaron los efectos de diferentes concentraciones de nisina (0,2, 0,4 y 0,8%) sobre la calidad sensorial, química y microbiológica y la vida útil de los filetes de lubina (Dicentrarchus labrax) envasados al vacío durante el enfriamiento y almacenamiento (4 ± 2 °C). La puntuación sensorial de los filetes crudos y cocidos aumentó con el tiempo durante el período de almacenamiento (p <0,05). El grupo de control con puntuación de 9,08 fue rechazado por los panelistas el día 12, mientras que los grupos de tratamiento con nisina fueron rechazados el día 14 con un rango de puntuación de 9,00-9,17. Como resultado de los análisis químicos, se obtuvieron valores más bajos (p < 0,05) de los grupos de nisina con baja rancidez oxidativa. Además, la nisina inhibió el crecimiento microbiano que muestra actividad antimicrobiana. En consecuencia, se evaluó que la aplicación de nisina (especialmente 0,8%) conservó la calidad organoléptica y prolongó la vida útil de la lubina

Maximizing the antioxidant capacity of Padina pavonica by choosing the right drying and extraction methods

Marine algae are becoming an interesting source of biologically active compounds with a promising application as nutraceuticals, functional food ingredients, and therapeutic agents. The effect of drying (freeze-drying, oven-drying, and shade-drying) and extraction methods (shaking at room temperature, shaking in an incubator at 60 \ub0C, ultrasound-assisted extraction (UAE), and microwave-assisted extraction (MAE)) on the total phenolics content (TPC), total flavonoids content (TFC), and total tannins content (TTC), as well as antioxidant capacity of the water/ethanol extracts from Padina pavonica were investigated. The TPC, TFC, and TTC values of P. pavonica were in the range from 0.44 \ub1 0.03 to 4.32 \ub1 0.15 gallic acid equivalents in mg/g (mg GAE/g) dry algae, from 0.31 \ub1 0.01 to 2.87 \ub1 0.01 mg QE/g dry algae, and from 0.32 \ub1 0.02 to 10.41 \ub1 0.62 mg CE/g dry algae, respectively. The highest TPC was found in the freeze-dried sample in 50% ethanol, extracted by MAE (200 W, 60 \ub0C, and 5 min). In all cases, freeze-dried samples extracted with ethanol (both 50% and 70%) had the higher antioxidant activity, while MAE as a green option reduces the extraction time without the loss of antioxidant activity in P. pavonica

Whole Grain Products, Fish and Bilberries Alter Glucose and Lipid Metabolism in a Randomized, Controlled Trial: The Sysdimet Study

Due to the growing prevalence of type 2 diabetes, new dietary solutions are needed to help improve glucose and lipid metabolism in persons at high risk of developing the disease. Herein we investigated the effects of low-insulin-response grain products, fatty fish, and berries on glucose metabolism and plasma lipidomic profiles in persons with impaired glucose metabolism.Altogether 106 men and women with impaired glucose metabolism and with at least two other features of the metabolic syndrome were included in a 12-week parallel dietary intervention. The participants were randomized into three diet intervention groups: (1) whole grain and low postprandial insulin response grain products, fatty fish three times a week, and bilberries three portions per day (HealthyDiet group), (2) Whole grain enriched diet (WGED) group, which includes principally the same grain products as group (1), but with no change in fish or berry consumption, and (3) refined wheat breads (Control). Oral glucose tolerance, plasma fatty acids and lipidomic profiles were measured before and after the intervention. Self-reported compliance with the diets was good and the body weight remained constant. Within the HealthyDiet group two hour glucose concentration and area-under-the-curve for glucose decreased and plasma proportion of (n-3) long-chain PUFAs increased (False Discovery Rate p-values <0.05). Increases in eicosapentaenoic acid and docosahexaenoic acid associated curvilinearly with the improved insulin secretion and glucose disposal. Among the 364 characterized lipids, 25 changed significantly in the HealthyDiet group, including multiple triglycerides incorporating the long chain (n-3) PUFA.The results suggest that the diet rich in whole grain and low insulin response grain products, bilberries, and fatty fish improve glucose metabolism and alter the lipidomic profile. Therefore, such a diet may have a beneficial effect in the efforts to prevent type 2 diabetes in high risk persons.ClinicalTrials.gov NCT00573781

Proximate analysis. Fatty acid profiles and mineral contents of meats: A comparative study

The aim of this study was to compare chemical parameters, fatty acid composition and mineral contents of farm animal meats which are marketed in Turkey. Different kinds of meats were purchased from the meat market including beef, lamb, broiler, turkey, ostrich and quail meat, which are mostly preferred for different reasons by consumers. However, little information exists about the composition of meats of different farm animal species. The results of proximate analysis showed that the high level of protein (24.38%) and low level crude fat (1.19 ± 0.13%) were found in turkey meats, while the low level of protein (18.75%) and high level fat (8.79%) were found in lamb meats. The fatty acid compositions of meats were in the range of 22.68-48.37% for saturated, 21.38-42.45% for monounsaturated and 3.75-47.47% for polyunsaturated acids. The highest micro mineral was determined as zinc (5.7417 ppm) in lamb and ostrich (5.0923 ppm). Practical Applications: Consumers attitudes toward meat " safety" greatly affect their overall choices and the variety of meat types available for sale. Some meats are more likely to cause heart disease - saturated fats and trans fats. These fats are usually found in foods from animals such as meat milk, cheese and butter. The dietary saturated fatty acids elevate serum cholesterol concentrations, whereas polyunsaturated fatty acids reduce serum cholesterol concentrations and monounsaturated fatty acids have little or no effect. Therefore, knowledge concerning the exact fatty acid composition of the meat is extremely important for the consumer and processing sector. This study provides comparative information to consumer and processing sector about proximate and fatty acid compositions and mineral contents of beef, lamb, broiler, turkey, ostrich and quail meats. © 2010, Wiley Periodicals, Inc

Fatty acid composition of achenes of cirsium taxa (Asteraceae, Carduoideae) from Turkey

PubMedID: 26959539The fatty acid compositions and total oil contents in achenes of 22 Cirsium taxa collected from different natural habitats in Turkey were investigated. The range of total fat in the taxa varied from 1.7% to 13.3%. The taxa contained palmitic (C16:0), stearic (C18:0), oleic (C18:1n-9), linoleic (C18:2n-6), and ?-linolenic (C18:3n-3) acid. Polyunsaturated fatty acids had the highest level, ranging from 52.1% to 75.2% (C18:2n-6) and 0.5%-17.3% (C18:3n-3). Total saturated (6.9%-17.4%), monounsaturated (11.7%-28.9%), and polyunsaturated (57.4%-79.9%) fatty acids varied substantially, whereas total unsaturated fatty acids ranged from 70.6% to 91.3%. Considerable variation was observed (P <0.05) within each taxon for these fatty acids, especially ?-linolenic acid (C18:3n-3). Fatty acid compositions of the 22 taxa were compared by cluster analysis (UPGMA) and principle component analysis (PCA) based on six major fatty acids. This is the first report on the lipid content and fatty acid composition of achenes of Cirsium taxa growing in different areas of Turkey. Fatty acid profiles, relative proportions and levels of fatty acids can be used as additional biochemical markers in the taxonomy of Cirsium