Identification of a novel umami compound in potatoes and potato chips

- A novel umami compound was identified in potato chips monosodium pyroglutamate (MSpG).
- Sensory verified MSpG contributed to umami at the oral mastication concentration.
- l-MSpG, d-MSpG, and l-MSG were the major umami compounds in the potato chips.
- MSpG was reported to be endogenous and thermally generated from MSG.
- Topically adding MSpG enhanced the saltiness, umami, and potato chip flavor.

The influence of frying time on the taste profile of potato chips was characterized. Direct comparison of isolates from potato chip samples fried for 170 s and 210 s indicated longer frying time increased the perceived umami intensity and decreased the sour intensity. The compounds responsible for the greater umami intensity were identified as monosodium l-pyroglutamate (l-MSpG) and monosodium d-pyroglutamate (d-MSpG). The reduction in sour intensity was attributed to the degradation of d-chlorogenic acid. MSpGs were endogenous in raw potatoes and also thermally generated from glutamic acid during frying. Taste recombination studies further confirmed the contribution of both compounds to the umami character of potato chips. Furthermore, time-intensity taste analysis revealed that topical addition of both l- and d-MSpG enhanced the perceived intensity of the umami taste and the overall flavor characteristic of the potato chips.