Effect of thermosonication on physicochemical, microbiological and sensorial characteristics of ayran during storage

Abstract

The aim of the study was to determine whether thermosonication extends the shelf life of ayran, an acidic milk drink. The effect of thermosonication at different temperatures (60, 70 and 80 °C) and times (1, 3 and 5 min) on the physicochemical and microbiological characteristics, and sensorial properties of ayran during storage were investigated. According to the results, thermosonication applied at 60 °C decreased lower the bacteria counts, although the Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus counts decreased as the temperature and time increased. The yeast and mold levels in samples treated with thermosonication were <1 log CFU mL(-1) during storage period. The ayran samples had non-Newtonian behavior, and the consistency coefficients of the thermosonicated samples were significantly higher than that of the heat-treated samples. Regarding serum separation, the most effective thermosonication treatment was applied at 70 °C for 3 min. The sensory properties of the thermosonicated samples were better than the thermal-treated samples after storage.

Effect of Supplementation with Green and Black Tea on Microbiological Characteristics, Antimicrobial and Antioxidant Activities of Drinking Yoghurt

“…The pH values of control drinking yoghurt (CDY) and sample with 4% green tea (4GDY) decreased at the end of the storage period (P<0.05). Similar results were obtained for control ayran (Turkish drinking yoghurt) and yoghurt supplemented with tea throughout the storage by other studies (Najgebauer-Lejko et al 2011; Marhamatizadeh et al 2013;Erkaya et al 2015).…”

Effect of ultrasound power on physicochemical and rheological properties of yoghurt drink produced with thermosonicated milk

“…There were insignificant differences (p>0.05) in titratable acidity values between control samples and yoghurt drinks produced with thermosonicated milk. Similar results were reported in yoghurt drinks by Uzunoglu (2012) and Erkaya et al (2015). Storage period influenced the acidity values significantly (p<0.05) while its interaction with thermosonication treatment was insignificant (p>0.05).…”

“…Serum separation and optimum consistency have been industrially used as quality parameters for commercial production. The effect of ultrasonication on the serum separation and the physicochemical and structural properties of yoghurt drinks have been previously reported by Ertugay et al (2012) and Erkaya et al (2015); however, these studies are focused on the application of ultrasound and/or thermosonication process on final products rather than raw milk. In this present study, the effect of ultrasound power on the physicochemical and rheological properties of yoghurt drink produced with thermosonicated milk was determined.…”

“…Storage time and its interaction with thermosonication treatment were also insignificant statistically (p>0.05). Erkaya et al (2015) produced yoghurt drinks by diluting yoghurt which had been manufactured with raw milk pasteurized at 90°C for 10min, and the authors found that L* values of yoghurt …”

Effect of in situ exopolysaccharide production on physicochemical, rheological, sensory, and microstructural properties of the yogurt drink ayran: An optimization study based on fermentation kinetics

“…However, to achieve the best EPS-producing conditions in our case, a multiple-response optimization study should be conducted. To the best of our knowledge, a limited number of studies have been conducted on optimization of fermentation conditions for EPS production and effect of EPS amounts on rheological properties of fermented milk products based on multiple response optimization (Kimmel et al, 1998;Erkaya et al, 2014). Furthermore, no study has investigated the effect of in situ EPS production on rheological properties of ayran, a yogurt drink.…”