title: The influence of the dose of calcium bisglycinate on physicochemical properties, sensory analysis and texture profile of kefirs during 21 days of cold storage.
abstract: BACKGROUND
  In the process of enrichment of dairy products a priority element is the proper selection of compounds that are a mineral carrier. Calcium bisglycinate is better absorbed by the body than inorganic forms of calcium. Moreover, the lactic acid which is produced in kefir fermentation and the presence of lactose have also a positive effect on the improvement of absorption of calcium. The aim of the present study was to determine the influence of the applied dose of calcium in the form of calcium bisglycinate on the physicochemical and sensory properties and texture of kefirs during 21-day period of cold storage.
  
  
  METHODS
  Processed cow milk was enriched with 0, 5, 10, 15, 20, 25 and 30 mg of calcium (for 100 g of milk), repasteurized (72°C, 1 min), cooled down (26°C), inoculated with Commercial VITAL kefir culture (Danisco, Poland) and fermented for 16 hours (26°C). The assessment of the influence of addition   of calcium bisglycinate on acidity, syneresis, texture and sensory characteristics (1-9 points) of kefirs was conducted at four fixed dates (after 1 day, 7 days, 14 days and 21 days of storage).
  
  
  RESULTS
  During successive weeks of cold storage in all experimental groups there was observed a tendency to decrease general acidity. On the 1st and 7th days of cold storage reduced whey leakage was observed in kefirs enriched with 25 mg and 30 mg Ca/100 g of milk. With increasing doses of enrichment with calcium both the hardness, adhesiveness and gumminess of kefirs decreased. The applied doses of calcium did not cause changes in the sensory characteristics such as colour and consistency of the fermented beverages.
  
  
  CONCLUSIONS
  Calcium bisglycinate may be used to enrich kefirs with calcium even with 30 mg of calcium in 100 g of milk without the modification of the product's parameters.
authors.affiliation: Department of Dairy Technology, University of Rzeszow, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Pawlos
authors.affiliation: Department of Dairy Technology, University of Rzeszow, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Znamirowska
authors.affiliation: Department of Dairy Technology, University of Rzeszow, Poland.
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szajnar
authors.affiliation: Department of Dairy Technology, University of Rzeszow, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Kalicka
mesh_terms: D000268:Adhesiveness; D002136:Calcium, Dietary / Q000032:analysis*; D055598:Chemical Phenomena; D005285:Fermentation; D063427:Food Quality; D061353:Food Storage; D005527:Food, Fortified / Q000032:analysis* / Q000382:microbiology; D005998:Glycine / Q000737:chemistry*; D006244:Hardness; D006801:Humans; D006863:Hydrogen-Ion Concentration; D000070716:Kefir / Q000032:analysis* / Q000382:microbiology; D007779:Lactobacillus acidophilus / Q000254:growth & development / Q000378:metabolism; D013294:Lactococcus lactis / Q000254:growth & development / Q000378:metabolism; D007934:Leuconostoc / Q000254:growth & development / Q000378:metabolism; D055595:Mechanical Phenomena; D009942:Organometallic Compounds / Q000737:chemistry*; D061352:Pasteurization; D012677:Sensation; D048249:Streptococcus thermophilus / Q000254:growth & development / Q000378:metabolism; D013559:Symbiosis; D015003:Yeasts / Q000254:growth & development / Q000378:metabolism
chemical_list: D002136:Calcium, Dietary; D009942:Organometallic Compounds; C000613503:calcium bisglycinate; D005998:Glycine
keywords: bisglycinate; calcium; kefir