Vacuum cooling of cooked turkish manti: effect of different cooling conditions on the physicochemical and microbiological properties of manti

In this thesis study, cooked Kayseri and triangular manti samples were cooled using traditional and vacuum cooling (VC) techniques, and the effect of the cooling process on cooling time, some quality characteristics of manti samples, and microbial activity during cold storage was determined. Manti samples were cooled either under a constant pressure of 10 mbar (VC10) and 20 mbar (VC20), with the traditional method at room temperature. The cooling times required for the central temperature of Kayseri manti to decrease from 80.0°C to 12.5°C and 20.0°C using the VC10 and VC20 methods were 15.67 and 18.00 min, respectively, whereas the traditional method took 35.33 min to lower the temperature to 25.0°C. For triangular manti, the cooling times were 21.17, 8.83, and 15.72 min for the traditional, VC10, and VC20 methods, respectively. VC ensured rapid and uniform cooling across all regions, while the traditional method resulted in uneven temperature distribution. During cooling using the traditional method, the cooling loss in Kayseri and triangular manti was 6.40% and 4.15%, respectively, whereas the loss increased to 10.26% and 8.54% with the VC10 method. The water-holding capacity of manti decreased when cooled traditionally. The cooling method did not significantly influence textural hardness, chewiness, springiness, gumminess, or energy value in triangular manti (p>0.05), but the VC method increased the internal stickiness of the manti compared to the traditional method (p<0.05). The textural hardness of Kayseri manti cooled with the VC10 method was found higher (p<0.05), whereas insignificant effects were observed on its other textural properties (p>0.05). VC accelerated water loss, causing the manti samples to harden. Differences in the CIELAB color values of manti in the initial days of storage diminished over time. Moreover, VC slowed the growth of both total aerobic mesophilic bacteria (TAMB) and yeast-mold compared to the traditional cooling method. Results demonstrated that the VC method provided significant advantages over the traditional method in terms of microbial growth inhibition and extending shelf life of cooked manti samples.