The quality and commercial value of a cheese depends on its organoleptic qualities and nutritional properties. Moreover, consumers and industry interest in a cheese may be increased if it also contains bioactive compounds with demonstrated health-promoting effects, such as gamma amino butyric acid (GABA), the main inhibitory neurotransmitter of the human central nervous system. Indeed, the ingestion of a GABA-enriched cheese has proven an anti-hypertensive effect on human [1]. In our group, we have demonstrated the presence of large quantities of GABA in several cheese samples from Europe [2]. Gy¿r-Moson-Sopron megyei Csemege is one of the most traditional cow¿s milk cheese specialities in Hungary. It has been registered as a protected geographical indication (PGI) in the European Union, based on tradition, a unique production method, the specific skills required for production, and the reputation of the cheese. To date, no published studies concerning to this cheese variety are available in the scientific literature. The aim of the present study was to initiate the chemical and microbiological characterization of Gy¿r-Moson-Sopron megyei Csemege PGI cheese. Thus, we determined the content of free proteinogenic aminoacids, and GABA by ultra-high performance liquid chromatography (UHPLC). Also, for safety considerations, we examined the content of biogenic amines. Finally, we determined the volatile organic composition of the cheese by gas chromatography coupled to mass spectrometry. The microbial diversity of Gy¿r-Moson-Sopron megyei Csemege PGI cheese was explored by means of viable counting on selective culture media. Moreover, individual colonies grown on MRS and M17 culture media whose morphology resembled that of lactic acid bacteria were cultured in acidic conditions in the presence of the precursor monosodium glutamate and screened for its potential ability to change the colour of the medium, due to the presumptive production of GABA. The confirmation of those GABA-production phenotypes was carried out by UHPLC. Currently, we are molecularly identifying the isolates able to produce GABA by 16s rRNA gene sequencing. References [1] Pouliot-Mathieu et al., 2013; doi: 10.1016/j.phanu.2013.06.003. [2] Redruello et al., 2020; doi: 10.1016/j.lwt.2020.109603.

Fuente de financiación: MCIN/AEI/10.13039/501100011033 (proyecto PID2020-112629RB-I00) y Plan de Ciencia, Tecnología e Innovación del Principado de Asturias 2018-2022, co-financiado por FEDER (AYUD/2021/50916).

Resumen del trabajo presentado en la 16ª Reunión de la Red Española de Bacterias Lácticas, celebrada en Madrid (España), los días 11 y 12 de mayo de 2023