Identification and Quantification of Key Volatile Flavor Compounds Employing Different Adjunct Starter Cultures in Reduced-fat Cheddar Cheeses by Using GC and GC-MS

Background and Objective: Reduced fat cheese often exhibits poor sensory quality due to the reduction of fat, which plays a critical role in flavor and texture. Therefore, there is the challenge to produce a reduced fat cheese with improved sensory attributes and texture that is also comparable to its full-fat counterpart. The main objective of this research was to investigate the effect of different adjunct starter cultures of Streptococcus thermophilus, Lactococcus helvetius and Lactococcus casei, alone or mixed, on the sensory prperties and volatile flavor compounds of reduced-fat cheddar cheeses (formulated with xanthan gum) and compare them with full-fat cheddar cheese during 75-day ripening.Materials and Methods: Eight treatments according to completely randomized design with a control cheddar cheese (no adjunct starter cultures) were designed. Extraction of the volatiles was carried out using headspace solid phase microextraction. Identification and quantification of volatile flavor compounds were done by gas chromatography-Mass spectrophotometry and gas chromatography, respectively. The sensory analyses were carried out by the 5-point hedonic scale, using trained panelists.Results and Conclusion: Among all the flavor compounds, more than 98% of the headspace volatile flavor compounds belonged to aldehydes, ketons, esters, alcohols, and acids. As compared to non-inoculated full-fat control, the use of Streptococcus thermophilus, Lactococcus casei and Lactococcus helveticus as adjunct starter cultures in the reduced fat cheddar cheese formulation increased the amount of volatile flavor compounds and enhanced the sensory attributes. The combination of this mixed culture with the reduced fat cheddar cheese containing xanthan gum as fat replacer is a viable alternative to improve the quality characteristics of reduced-fat cheddar cheese.Conflict of interest: The authors declare that there is no conflict of interest