Influence of microflora on texture and contents of amino acids, organic acids, and volatiles in semi-hard cheese made with DL-starter and propionibacteria.

The microflora of semi-hard cheese made with DL-starter and propionic acid bacteria (PAB) is quite complex, and we investigated the influence of its variation on texture and contents of organic acids, free amino acids, and volatile compounds. Variation in the microflora within the normal range for the cheese variety Grevé was obtained by using a PAB culture in combination with different DL-starters and making the cheeses at 2 dairy plants with different time and temperature profiles during ripening. Propionic acid bacteria dominated the microflora during ripening after a warm room period at levels of log 8 to log 9 cfu/g, which was about 1 log unit higher than the total number of starter bacteria and about 2 log units higher than the number of nonstarter lactic acid bacteria. Eye formation was observed during the warm room period and further ripening (at 8 to 10°C). The amounts of acetate, propionate, total content of free amino acids, 2-propanol, and ethyl propionate in the ripened cheeses were related to the number of PAB. A decrease in the relative content of Asp and Lys and increase of Phe over the ripening time were different from what is observed in semi-hard cheese without PAB. The occurrence of cracks was higher in cheeses with more hydrolyzed α(S1)- and ß-casein, higher content of free amino acids, lower strain at fracture (shorter texture), and a greater number of PAB.

Benefits of growth hormone treatment on bone metabolism, bone density and bone strength in growth hormone deficiency and osteoporosis.

Bone mass is reduced in patients with GH deficiency (GHD) leading to an increased vertebral fracture rate and clinically significant osteoporosis. Patients with GHD of juvenile onset have reduced skeletal mineralization. When substituting GH in patients with GHD, bone turnover is increased and bone mineral density initially decreases during the first year due to the increase in remodelling space. From the experience in patients with acromegaly, cortical bone mass is increased and trabecular bone mass is normal in eugonadal or decreased in the hypogonadal patients. However, bone mineral content and bone area are increased leading to a higher biomechanical competence of bone as shown in rats. In patients with GHD of juvenile onset, mineralization and bone maturation are achieved during treatment with GH in adult life after having reached final body height leading to an increase in bone mass. The GH/ IGF-I system is dysregulated in patients with post-menopausal osteoporosis. This is shown by reduced systemic IGF and IGFBP-3-levels in osteoporosis suggesting a decrease of endogenous GH-secretion or a dysregulation of the GH receptor system which is beyond the normal ageing process of the GH/IGF system, the "somatopause". A premature somatopause may be responsible for the dysregulation in some patients with osteoporosis. However, 24-h GH profiles do not differ between patients suffering from osteoporosis or osteoarthritis. Treatment of osteoporosis with GH might be beneficial due to the increased bone metabolism and improved bone geometry which occurs with GH. The substantial increase of bone remodelling achieved with GH may be helpful during late post-menopause with decreased bone turnover and impaired osteoblastic function. Using GH to prevent physiological bone loss that occurs with age seems possible, but has to be discussed on an ethical and economic basis.