Czech Journal of Food Sciences, 2000 (vol. 18), issue 1

Multivariate calibration of raw cow milk using NIR spectroscopy.Original Paper

O. Kukačková, L. Čurda, J. Jindřich

Czech J. Food Sci., 2000, 18(1):1-4

At present, mid-IR spectroscopy is the preferred rapid method for milk analysis. NIR spectrometers have some advantages in comparison with mid-IR. The purpose of this study was to see a possibility of determining the total solids, fat and protein in milk. The total number of preserved raw cow milk samples was 65. NIR spectra were recorded in duplicate on the NIRS 6500 instrument (NIRSystems, Inc.) using a fiber optic probe. The reference method for milk samples used for calibration model was determined by oven drying to measure the total solids, by Gerber method to measure fat content, and by Kjeldahl method to measure protein content. A commercial...

Changes of iodine content in milk of cows treated with BetadineOriginal Paper

L. Čurda, J. Rudolfová

Czech J. Food Sci., 2000, 18(1):5-8

The purpose of this study was to assess the changes of iodine content in milk associated with the treatment of milch cows with the disinfecting preparation Betadine on basis of active iodine. Altogether 17 samples were taken from milch cows treated after milking by immersion of teats into Betadine solution; further 3 samples from cows after uterine irrigation. Ten check samples from milch cows without treatment were analyzed too. The content of iodine in milk was determined by the sensitive spectrophotometric method based on the Sandell-Kolthoff reaction brought to an end with addition of ammonium ferrous sulphate. Organic matter of milk was destroyed...

Influence of germination on the carbohydrate composition of peaOriginal Paper

P. Kadlec, A. Rubecová, Z. Réblová, H. Štarhová, Z. Bubník

Czech J. Food Sci., 2000, 18(1):9-13

Influence of germination on the carbohydrate composition of pea seeds was studied. After 4 days of germination the content of raffinose family oligosaccharides (RFO) in pea decreased to 17.5% of the original value and the ratio sucrose/RFO in cotyledons increased from 0.5 to 4.5.

Storage of sugar beet raw juiceOriginal Paper

A. Hinková, Z. Bubník, H. Štarhová, V. Pour, P. Kadlec

Czech J. Food Sci., 2000, 18(1):14-22

Big disadvantage in sugar beet processing is the possibility of sugar beet treatment only during three month period. This paper deals with possibilities of raw juice long term storage without adding of any chemical additives. For this purpose sugar beet raw juice concentrates were prepared on the climbing film evaporator during two sugar campaigns 97/98 and 98/99. The final refractometric dry solid content varied from 40 to 72%. Some juices were pre-treated by micro- or ultrafiltration. Concentrates were stored for the period of 5 months (campaign 97/98) and 7 months (campaign 98/99) in a stock-room without any heating. Temperatures in the stock-room...

Application of computer image analysis for evaluation and control of the sucrose crystallization processOriginal Paper

Z. Bubník, P. Kadlec, H. Štarhová, V. Pour, A. Hinková

Czech J. Food Sci., 2000, 18(1):23-28

The paper deals with applications of computer image analysis to evaluation and control of crystallisation process in technical sugar solutions. Fields of application of this system: The kinetics study of the cooling crystallisation of sucrose from technical sugar solutions, measurement of the solubility of sucrose in technical sugar juice by the saturoscopy method, measurement of crystal size distribution.

Chromatography of barley b-glucansOriginal Paper

J. Čopíková, A. Sinitsya, K. Vaculová

Czech J. Food Sci., 2000, 18(1):29-34

Size exclusion chromatography with a set of two columns Separon Hema Bio 1000 and Separon Hema Bio 100 was found to give efficiency for the determination of molecular mass of ß-glucans isolated from barley. The set was calibrated with dextrans of known molecular mass. b-glucans from the barley cultivars ranged in molecular mass from 1.2 × 106 g/mol to 1.5 × 106 g/mol in the case of soluble b-glucans and from 0.9 × 106 g/mol to 1.4 × 106 g/mol in the case of total b-glucans. The new Czech varieties had higher values of molecular mass in comparison to parental genotypes. The differences between molecular mass of parental genotypes of high glucan barley...

Resveratrol - occurrence in wine originating from Czech vineyard regions and effect on human healthOriginal Paper

K. Melzoch, V. Filip, D. Buckiová, I. Hanzlíková, J. Šmidrkal

Czech J. Food Sci., 2000, 18(1):35-40

Resveratrol is a substance of a natural character, naturally present in some foods, namely in wine. The grape peels of Vitis vinifera contain about 50 to 100 mg of resveratrol/g and the average resveratrol concentration in red wines produced in the world fluctuates between 1.0 to 3.0 mg/l. A few biological activities were discovered with resveratrol in the last few years such as positive action against some cardiovascular diseases described as so called French paradox and anti-cancer chemo-preventive activity. The denominators of those activities are anti-oxidizing and free radical scavenging features of resveratrol molecule. As expected,...