Improvement of Ayran quality by the selection of autochthonous microbial cultures

• Published in: Food microbiology Vol. 60; pp. 92 - 103
• Main Authors: Baruzzi, Federico, Quintieri, Laura, Caputo, Leonardo, Cocconcelli, PierSandro, Borcakli, Mehlika, Owczarek, Lubomiła, Jasińska, Urszula T., Skąpska, Sylwia, Morea, Maria
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.12.2016
• Subjects: Acidification rate; Animals; Bacterial Typing Techniques; Biodiversity; Cultured Milk Products - analysis; Cultured Milk Products - microbiology; Food Quality; Food Storage - standards; Lactobacillus - classification; Lactobacillus - genetics; Lactobacillus - isolation & purification; Lactobacillus delbrueckii; Lactobacillus fermentum; Lactobacillus helveticus; Lactobacillus paracasei; Microbial biodiversity; Microbial Viability; Molecular Typing; Pilot Projects; Pilot-scale production; Proteolysis; Sensory analysis; Streptococcus thermophilus; Streptococcus thermophilus - genetics; Streptococcus thermophilus - isolation & purification; Taste; Traditional fermented milk; Turkey; Yogurt - analysis; Yogurt - microbiology; Sensory analysis; Pilot-scale production; Microbial biodiversity; Proteolysis; Acidification rate; Traditional fermented milk
• ISSN: 0740-0020; 1095-9998
• DOI: 10.1016/j.fm.2016.07.001

Ayran is a traditional Turkish milk drink which is fermented and salted. Inadequate production and storage conditions contribute to its variable organoleptic quality and stability during shelf-life. A thorough physico-chemical, nutritional and microbial characterization of artisanal Ayran was carried out in order to standardize its overall quality without altering its original traits. Ayran microbial ecosystem was largely dominated by Streptococcus thermophilus (ST) and Lactobacillus delbrueckii subsp. bulgaricus (LDB). High counts of other lactic acid bacteria species, including Lactobacillus helveticus (LH), Lactobacillus fermentum (LF), and Lactobacillus paracasei (LP), were also found. Selected LDB, LP and LH strains grew well in milk displaying fast acidification and high proteolysis, differently from ST and LF strains that did not cause noticeable changes. A selected autochthonous three-strain culture (TSC), composed of one strain of LDB, LP and ST, was applied for the pilot-scale production of traditional Ayran. The Ayran produced with this TSC resulted in the most extensive shelf-life (one month) and in the best terms of its nutritional and sensory quality nevertheless altering its typical pleasant yogurt and cottage cheese notes. This TSC is at disposal of SMEs who need to standardize the overall quality of this traditional fermented milk, preserving its typical traits. •Molecular biotyping allowed to distinguish 34 LAB strains and other microorganisms.•LAB strains evaluated for acidification over milk fermentation and cold storage.•5 LAB strains evaluated for viability and proteolysis.•Ayran production at pilot-scale level with three autochthonous strains.•Ayran sensory quality and shelf-life improvement controlling spoilage and defects.