Contribution of the lactoperoxidasesystem to the keeping quality of pasteurized milk
The lactoperoxidase system is a naturalantimicrobial system that can play an active role in the keeping quality of raw milk.However, there is little information on the activation of the lactoperoxidase system aftermild heat treatments such as pasteurization. The keeping quality of milk pasteurized at 72C for 15 seconds has been found to be better than that of milk heated at 80 C for 15seconds. The kinetics and mechanism of lactoperoxidase action were investigated. Milkspasteurized at 72 and 80 C were stored at 8 C and the keeping quality was assessed dailyover 16 days by measuring pH, clot-on boiling, alcohol stability, total viable count,titratable acidity and dissolved oxygen. The results showed that pasteurizationtemperature is critical to the keeping quality of milk.
Barrett N. E., Grandison A.S., Lewis M.J. Journal of Dairy Research 1999(February), 66 (1), 73-80 (19 ref.) En:en (saan: 491900)
Antibacterial activity associatedwith Bifidobacterium adolescentis
Bifidobacteria are naturally present in thehuman intestine, and are beneficial. However, the authors report that in adolescentsthe number of these bacteria fall, but can be restored to previous levels by drinking abifidus milk beverage. The ability of Bifidobacterium adolescentis andBifidobacterium bifidum to inhibit the growth of Escherichia coli, Shigella sonnet,Staphylococcus aureus, Bacillus cereus, Salmonella typhosa and Pseudomonas aeruginosa isdiscussed. Both Bifidobacterium bifidum and Bifidobacterium adolescentis were foundto have antibacterial properties.
Khedkar J.N., Dave J.M., Sannabhadti S.S. Journal of Food Science andTechnology 1998 (November-December), 35 (6), 527-529 (14 ref.) En:en (saan:491310)
Getting more out of milkhomogenisation
Factors affecting the fat globule size inhomogenized milk are considered. Stoke’s Relation describes the correlation betweenfat globule size and creaming rate. The influence of homogenization pressure andflow rate on fat globule size are important. Key factors to consider when choosing ahomogenizer, or optimizing the efficiency of an existing homogenizer are reviewed. Acost-saving and energy-saving case study is presented. Finally, the advantages of the newTetra Alex homogenizer, from Tetra Pak, are outlined.
Senno B. Milk Industry International Technical and Research Supplement 1999(February), 101 (2), 4-6 (0 ref.) En (saan: 489927)
Standardisation and evaluation oflassi prepared using Lactobacillus acidophilus and Streptococcus thermophilus
Lassi was prepared from standardized mixedmilk using Lactobacillus acidophilus (three strains) and Streptococcus thermophilus (onestrain). Sugar levels were 8%, 10% or 12%, and the stabilizers used were guar gum, gumacacia, sodium alginate, and guar gum plus sodium alginate. The final productstudied contained 10% sugar, 0.05% guar gum plus sodium alginate (1:3) and theLactobacillus acidophilus I4 strain. Samples were stored in glass bottles and LDPEpouches. The sensory scores fell over the 15-day study period, and changes inflavour were most significant. Lassi stored in glass bottles remained acceptableafter 21 days of storage. Levels of Lactobacillus acidophilus and Streptococcusthermophilus remained satisfactory over the study period. The former showedantibacterial, inhibitory and antitumour activity. The final lassi product obtainedwas therefore not only organoleptically acceptable and stable, but probably also possessedtherapeutic properties.
Patidar S.K., Prajapati J.B. Journal of Food Science and Technology 1998(September-October), 35 (5), 428-431 (18 ref.) En (saan: 490012)
Production of pineapple flavouredfermented milk to suit Caribbean taste
Fermented milk drinks have become popular,owing to their unique taste and functional properties. Lactobacilli are known tostimulate the immune system, and produce lactic acid, acetic acid, hydrogen peroxide andbacteriocins, which have antibacterial properties. The production of a fermentedmilk drink is described. Lactobacillus bulgaricus was used as the starter organism. The drink was found to be satisfactory in terms of both its microbial stability andsensory characteristics.
Badrie N., Gangapersad S., Wickham L.D., Donawa A. Journal of Food Science andTechnology 1998 (November-December), 35 (6), 515-517 (12 ref.) En:en (saan: 491306)
The Texel Symposium
A recent Texel symposium was devoted to thetopic of fermented milk products. The characteristics and method of manufacture ofkefir and kishk are described. Ways of improving the texture and mouthfeel ofyoghurt, by changing the formulation, are also discussed.
Russell P. Milk Industry International 1999 (February), 101 (2), 21-22(0 ref.) En (saan: 489926)