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Nowadays, there is a growing interest in the physiological benefits of natural antioxidants in foods. Honey bee products, especially propolis and pollen, have strong antioxidative activity and beneficial effects in human body. The aim of this study was to determine the total phenolic and total flavonoid contents and antioxidant activities of propolis and pollen, as well as bioaccessibility of these products by an in-vitro model simulating gastrointestinal digestion. Total phenolic content, total flavonoid content and antioxidant activity analysis were applied to all samples as well as samples collected after the application of in-vitro gastrointestinal method. Phenolic profiles of propolis and pollen samples were also identified by HPLC-PDA. Results indicated that total phenolic contents of IN fractions (bioaccessible fraction) of propolis and pollen was 2.0 and 2.1 mg GAE/g; total flavonoid content was 0.9 and 0.2 mg QE/g; total antioxidant activity was 19.6 and 0.6 mg TE/g, respectively. Percentages of the IN fraction of propolis and pollen were 1% and 9% for total phenolic content; 0.2% and 1% for total flavonoid content; 4% and 3% for total antioxidant activity. Phenolic compounds including caffeic acid, p-coumaric acid, ferrulic acid, quercetin, pinobanksin, apigenin, t-cinnamic acid, luteolin, pinocembrin, chrysin, galangin, kaempferol and pinostrobin were detected in propolis, and 2-hydroxycinnamic acid, quercetin-3glucoside, quercetin, myricetin, luteolin, quercetin-3-galactoside, kaempferol, and galangin were detected in pollen samples. Investigación de la bio-accesibilidad in vitro de propóleos y el polen que utilizan un sistema de digestión gastrointestinal simulada ResumenHoy en día, hay un creciente interés en los beneficios fisiológicos de los antioxidantes naturales presentes en los alimentos. Productos de la abeja de la miel, especialmente propóleo y polen, tienen una fuerte actividad antioxidante y efectos beneficiosos para el cuerpo humano. El objetivo de este estudio fue determinar el contenido total fenólico y de flavonoides y la actividad antioxidante de propóleos y polen así como la bio-accesibilidad de estos productos mediante un modelo in vitro que simula la digestión gastrointestinal. Se analizaron el contenido fenólico total, el contenido total de flavonoides y la actividad antioxidante en todas las muestras, así como en las muestras recogidas después de la aplicación del método in vitro gastrointestinal. Los perfiles fenólicos del propóleo y las muestras de polen también fueron identificados por HPLC-PDA. Los resultados indicaron que el contenido total de fenólicos de fracciones (fracción EN bioaccesibles) de propóleos y polen fue de 2,0 y 2,1 mg GAE/g; el contenido total de flavonoides fue de 0,9 y 0,2 mg QE/g, la actividad antioxidante total fue de 19,6 y 0,6 mg TE/g, respectivamente. Los porcentajes de la fracción IN del propóleo y el polen fueron 1% y el 9% para el contenido de fenoles totales, 0,2% y 1% para el contenido total de flavonoides; 4% y 3% para la actividad antioxidante ...

Tea and herbal infusions are among the major contributors of phenolic compounds, specifi cally fl avonoids, in our daily diet. Honey is another antioxidant-rich food that is widely used as a natural sweetener. In this work, the effects of honey addition on antioxidant properties of different herbal teas were investigated. For this purpose, 2 different types of honey (fl ower and pine honey) were added into 9 different herbal teas (melissa, green tea, rosehip, sage, echinacea, fennel, linden, daisy, and ginger) at 4 different temperatures (55˚C, 65˚C, 75˚C, and 85˚C), and the changes in the content of total pheolics, total fl avonoids, and total antioxidant capacity were determined. The total phenolic content and the total antioxidant capacity of the honey-added-tea samples were found to be increased (up to 57% for both), especially with pine honey and at higher temperatures of honey addition. The fi ndings of this study supported the use of honey as a natural sweetener in tea in order to be able to benefi t from the health-enhancing antioxidative properties of these two promising food products.

Firatligil-Durmuş E., Šárka E., Bubník Z. (2008): Image vision technology for the characterisation of shape and geometrical properties of two varieties of lentil grown in Turkey. Czech J. Food Sci., 26: 109-116.Geometrical features of lentil seeds (lens culinaris Medik) were analysed using the image analysis LUCIA system Ver. 3.52. The values of the weight of 1000 kernels, kernel density, specific volume, specific surface area, and surface area of 1000 kernels of red and green lentils were determined as 66.61 and 138.56 g, 1504.5 and 1376.4 kg/m 3 , 0.6647 and 0.7265 cm 3 /g, 0.594 and 0.579 m 2 /kg, 395.4 and 801.9 cm 2 , respectively. The lentil volume was simulated by an oblate spheroid and two sphere segments and the volumes obtained with both models were compared with that obtained by pycnometric method. Percentage differences of the two sphere segment approximation for red and green lentils were 4.4% and 4.2%, respectively. The height (thickness) of lentils was constant and practically the same with both varieties (2.6 mm) and therefore it was possible to simplify the geometrical models. Thus, 2D image analysis is suitable for a quick evaluation of the specific volume and surface area of grains on the basis of the projected area (equivalent diameter) without the measurement of the height. Image processing provides a simple, rapid, and non-invasive methodology to estimate lentil geometric features and engineering parameters.

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