Effect of somatic cell count on milk composition and mozzarella cheese quality

The aim of this study was to investigate the effect of somatic cell count (SCC) on mozzarella cheese quality. Three categories of raw milk were selected: low (SCC 987 000 cells/ml). Cheeses were produced on the same day of milk collection and were vacuum packed in plastic bags and analysed weekly for 60 days at cold storage (4 °C). As somatic cell count increases, casein content, casein as a percentage of true protein, lactose content, and titratable acidity decrease significantly in raw milk. No significant differences were observed in moisture, fat, and total protein contents among mozzarella cheese samples from the different SCC categories. However, cheese samples produced from high SCC milk had significantly higher pH (6.83) compared to samples produced with low and medium SCC milk, 5.58 and 5.46, respectively. The extension of proteolysis was not significant for cheese samples made from raw milk with low SCC during the first 30 days of cold storage. Proteolysis levels increased significantly on the 15th storage day for cheeses made with medium and high SCC, whereas significant increases were only observed on the 45th storage day for cheeses made with low SCC

Allometric scaling and age-related differences in change of direction speed performances of young soccer players

Purpose: The purposes of this study were to compare change of direction speed (CODS) performances between different age categories (i.e., U-10, U-12, U-13, and U-18) and to develop allometric exponents for scaling this quality. Material and method: Data were gathered with the participation of 101 male soccer players (mean ± SD; age = 12.5 ± 2.9 years, mass = 44.4 ± 14.7 kg, height = 149.3 ± 17.7 cm, and leg length = 75.7 ± 13.1 cm). All players performed the Illinois change of direction speed test (ICDST). Results: U-18 players achieved significantly better results in ICDST compared with the other groups, whereas U-10 players had the lowest performances (F = 48.78, P 0.05). The ICDST performances were significantly associated with body mass (r = −0.58; P 0.05), indicating the effectiveness of allometric exponents in partialing out the effect of anthropometric measures on ICDST's compared to ratio scaling. Conclusion: Results indicated differences in CODS performance among soccer players of different age categories. These results demonstrated that developing allometric exponents are effective in controlling for anthropometric measures

Effects of time storage and analytical temperature on Fossomatic cell counts in cows milk

This study evaluated the effects of time of storage and analytical temperature on the somatic cell count (SCC) in cow milk. To this end, counts were performed on 1200 cow milk samples using a flow cytometry cell counter (Fossomatic 400). The conditions tested were analytical temperature, use of a preservative [without preservative (WP) and with bronopol (BR)], and age of the milk. Tests were performed at two temperatures (40 and 60 degrees C) on preservative-free samples, 1 hour after collection and on samples preserved with potassium dichromate (PD), at 1 hour and at 1 to 4 days post-collection. Test temperature did not modify the SCC of the milk samples analyzed. Heating samples 1 h post-collection at 60 degrees C failed to improve the SCC results. Similar counts were obtained for PD-preserved samples stored for 1 to 4 d at 4 degrees C, suggesting the possibility of performing Fossomatic SCC on cow milk samples stored for this length of time

Field and laboratory testing in young elite soccer players

Aim: To determine if there are correlations between the physical fitness of young soccer players assessed by field and laboratory testing. Methods: Thirty four male soccer players took part in the study (mean (SD) age 17.5 (1.1) years, height 177.8 (6.7) cm, weight 70.5 (6.4) kg). Maximal oxygen uptake (VO(2)MAX) during treadmill running and vertical jump height on a force platform were measured in the laboratory. Field tests consisted of a soccer specific endurance test (Bangsbo test) and 30 m sprint with 10 m lap times. Results: The Bangsbo test correlated with the lowest velocity associated with VO(2)MAX (vVO(2)MAX; R(2) = 0.55, p<0.001), but not with VO(2)MAX. Sprint times at 30 m and 20 m were related to peak extension velocity and peak extension force measured during vertical jumping, but not to vertical jump height per se. The jumping force and velocity could explain 46% of the 30 m sprint performance (R(2) = 0.46, p<0.001). Conclusion: The Bangsbo test and 30 m sprint test correlate with vVO(2)MAX and vertical jump force and velocity respectively. The Bangsbo test does not give a good estimate of VO(2)MAX in young soccer players

Appropriate interpretation of aerobic capacity : allometric scaling in adult and young soccer players

Utilisation d'équations allométriques pour déterminer la relation entre le VO2 max, l'économie de la course et la masse corporelle lors de tests d'effort jusqu'à épuisement chez des joueurs de football âgés de 14 ans ou de 24 ans

Endurance training and testing with the ball in young elite soccer players

Background: The aerobic capacity of soccer players substantially influences their technical performance and tactical choices. Thus, the assessment of soccer players' aerobic performance should be of interest for soccer coaches in order to evaluate and improve their endurance training sessions. In this study, we present a new test to assess aerobic performance in soccer by means of a specific dribbling track: the Hoff test. We further determined whether improvement in maximal oxygen uptake was reflected in increased distance covered in the Hoff test. Methods: We tested 18 male soccer players (14 years old) both in the laboratory and using the Hoff test before and after 8 weeks of soccer training. Results: The distance covered in the Hoff test correlated significantly with maximum oxygen uptake, and improved by 9.6% during the 8 week training period, while maximum oxygen uptake and running economy improved by 12 and 10%, respectively. Backward multiple regression showed maximum oxygen uptake to be the main explanatory variable for the distance covered in the Hoff test. Conclusion: The present study demonstrated a significant correlation between laboratory testing of VO(2max) and performance in the Hoff test. Furthermore, training induced improvements in VO(2max) were reflected in improved performance in the Hoff test. We suggest that it should be a goal for active U-15 soccer players to cover more than 2100 metres in the Hoff test, as this requires a VO(2max) of above 200 ml/kg(0.75)/min, which should serve as a minimum in modern soccer

Effects of adding a preceding run-up on performance, blood lactate concentration and heart rate during maximal intermittent vertical jumping

In this article, twenty seven experience centered industrial design projects leading to kansei representatins were analysed. Information was gathered from interviews with former project team members and from an analysis of the projects final report. A model of kansei related design information based on these discussions is finally presented.Financement industriel