Title: | "Influence of microflora on texture and contents of amino acids, organic acids, and volatiles in semi-hard cheese made with DL-starter and propionibacteria" |
Author(s): | Rehn U; Vogensen FK; Persson SE; Hallin Saeden K; Nilsson BF; Ardo Y; |
Address: | "Department of Food Science, Faculty of Life Sciences, University of Copenhagen, Rolighedsvej 30, DK-1958 Frederiksberg C, Denmark" |
ISSN/ISBN: | 1525-3198 (Electronic) 0022-0302 (Linking) |
Abstract: | "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 Greve 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 degrees 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 alpha(S1)- and beta-casein, higher content of free amino acids, lower strain at fracture (shorter texture), and a greater number of PAB" |
Keywords: | Amino Acids/analysis Animals Cheese/*analysis/*microbiology Food Handling/methods Food Microbiology Lactococcus lactis/*metabolism Propionates/analysis Propionibacterium/*metabolism Volatile Organic Compounds/analysis; |
Notes: | "MedlineRehn, U Vogensen, F K Persson, S-E Hallin Saeden, K Nilsson, B F Ardo, Y eng Research Support, Non-U.S. Gov't 2011/02/23 J Dairy Sci. 2011 Mar; 94(3):1098-111. doi: 10.3168/jds.2010-3146" |