title: The effect of addition of selected milk protein preparations on the growth of Lactobacillus acidophilus and physicochemical properties of fermented milk.
abstract: BACKGROUND
  The intake of fermented milk products, especially yoghurts, has been systematically increasing for a few decades. The purpose of this work was to obtain milk products fermented with a mix of bacterial cultures (yoghurt bacteria and Lactobacillus acidophillus LA-5) and enriched with selected milk protein preparations. Secondly, the aim of the work was to determine physiochemical and rheological properties of the obtained products.
  
  
  METHODS
  The following additives were applied in the experiment: whey protein concentrate (WPC 65), whey protein isolate (WPI), demineralised whey powder (SPD), caseinoglycomacropeptide (CGMP), α-lactalbumin (α-la), sodium caseinate (KNa) and calcium caseinate (KCa). Milk was fermented using probiotic strain Lactobacillus acidophillus LA-5 and a typical yoghurt culture. The products were analysed in terms of the survivability of bacterial cells during refrigerated storage, rheological properties and syneresis. Fermented milk products were obtained using blends of bacterial strains: ST-B01:Lb-12 (1:1), ST-B01:Lb-12:LA-5 (1:1:2).
  
  
  RESULTS
  Milk beverages fermented with typical yoghurt bacteria and LA-5 strain showed intensive syneresis. The addition of LA-5 strain caused formation of harder acid gels, comparing to typical yoghurts. Milk products which were prepared from skimmed milk possessed higher values of hardness and consistency coeﬃcient. The increase of concentrations of milk preparations (except of WPI) did not cause significant differences in the hardness of acidic gels obtained by fermentation of mixed culture with a probiotic strain.
  
  
  CONCLUSIONS
  The applied preparations improved physiochemical properties of the milk beverages which were prepared with a probiotic strain. The increase of protein milk preparations concentration resulted in a gradual decrease of the secreted whey. Among the products that were made of full milk powder and were subjected to three weeks of refrigerated storage the highest survivability of Lb. acidophilus LA-5 was noticed in the samples fortified with 1% WPC.
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Gustaw
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Kozioł
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Wojciech
authors.initials: W
authors.lastname: Radzki
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Skrzypczak
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Monika
authors.initials: M
authors.lastname: Michalak-Majewska
authors.affiliation: Department of Milk Technology and Hydrocolloids, University of Life Sciences in Lublin, Poland.
authors.forename: Bartosz
authors.initials: B
authors.lastname: Sołowiej
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Aneta
authors.initials: A
authors.lastname: Sławińska
authors.affiliation: Department of Fruits, Vegetables and Mushrooms Technology, University of Life Sciences in Lublin, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Jabłońska-Ryś
mesh_terms: D000818:Animals; D002364:Caseins / Q000737:chemistry / Q000378:metabolism; D055598:Chemical Phenomena; D043302:Cultured Milk Products / Q000032:analysis / Q000382:microbiology*; D005285:Fermentation; D061353:Food Storage; D057141:Food, Preserved / Q000032:analysis; D006020:Glycopeptides / Q000737:chemistry / Q000378:metabolism; D007768:Lactalbumin / Q000737:chemistry / Q000378:metabolism; D007779:Lactobacillus acidophilus / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D048668:Lactobacillus delbrueckii / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D000069996:Ligilactobacillus salivarius / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D055595:Mechanical Phenomena; D008892:Milk / Q000737:chemistry; D008894:Milk Proteins / Q000737:chemistry / Q000378:metabolism*; D011044:Poland; D012034:Refrigeration; D012212:Rheology / Q000379:methods; D013559:Symbiosis; D000067816:Whey Proteins / Q000737:chemistry / Q000378:metabolism; D015014:Yogurt / Q000382:microbiology
chemical_list: D002364:Caseins; D006020:Glycopeptides; D008894:Milk Proteins; D000067816:Whey Proteins; C484216:calcium caseinate; C020251:kappa-casein glycomacropeptide; D007768:Lactalbumin
keywords: Lactobacillus acidophillus; milk protein preparations; rheology; syneresis