[Show abstract][Hide abstract] ABSTRACT: The objective of this work was to study the decrease of alkaline phosphatase (ALP) activity during heat treatment of ovine and caprine milk in comparison to that of bovine milk. For this purpose, different samples from the three milk kinds were subjected to heat treatment at 59°C under different time conditions and the residual ALP activity was determined using the IDF reference method and the automated fluorimetric IDF method. The heat treatment reduced the ALP activity in bovine milk slower (P
No preview · Article · Oct 2006 · Small Ruminant Research
[Show abstract][Hide abstract] ABSTRACT: Lipolysis was studied during ripening of traditional Feta cheese produced in two small dairies, A and B. The cheeses were made from a thermized mixture of ewes’/goats’ milk by using yoghurt as starter and artisanal rennet from lambs’ and kids’ abomasa (cheese A) or mixed artisanal rennet with calf rennet (cheese B).The acid degree value and the free fatty acids (FFA) contents in both cheeses increased sharply up to 18 d (pre-ripening period at 15 °C) and continued to increase throughout ripening. In both mature cheeses, acetic acid was found at high levels (13–18% of the total FFAs). However, except for this, all FFA contents differed significantly (P
[Show abstract][Hide abstract] ABSTRACT: Feta cheeses were manufactured with commercial calf rennet and artisanal liquid rennet from kids and lambs abomasa with an aim to investigate the influence of rennet type on the characteristics of this cheese variety. The two rennets had similar chymosin to pepsin ratios and they were used in quantities with the same total milk coagulating activity. The use of traditional rennet had no significant effect on the evolution of physicochemical composition (pH, total solids, ash, NaCl, fat, total protein) or on the evolution of proteolysis (water-soluble nitrogen expressed as percentage of total nitrogen, free amino acids expressed as mmol Leu, residual αs-casein and reversed phase HPLC profiles) during the ripening. The textural characteristics of mature 60d-old cheeses were not significantly different. The microbiological quality of traditional rennet significantly affected the enterococci and coliform counts of 3d-old cheeses but this influence was eliminated in the mature 60d-old cheeses. The significantly higher flavour scores of mature Feta made with traditional artisanal liquid rennet were in accordance with the significantly higher C4:0 and C10:0 FFA contents resulting from the lipase activity of traditional rennet.