Natural food and beverage flavour enhancers - Natural Food Additives, Ingredients and Flavourings - page 91

In a patent concerning salt taste enhancement, Guerrero et al. (1998) defi ned
the preparation of an enzymically hydrolysed protein in the absence of sodium.
The resulting hydrolysate contained peptides as well as free lysine and arginine,
with an ammonium salt, and could be dehydrated and added to foods to enhance
salty taste and, in some cases, fl avour. An earlier study by Seki et al. (1990)
highlighted two peptides (ornithyltaurine and ornithyl- β -alanine) that gave a salty
taste and noted that the pH of the peptide solutions was important to achieve the
saltiness.
Overall it appears that further research is needed to conclude whether short-
chain peptides have a real and substantial part to play in taste and fl avour
enhancement of complex food systems. From the contradictory evidence available
to date, it would appear that their role must be within enhancement of mixtures
that already contain other umami stimuli.

4.4 Maillard-derived taste enhancers
Taste-active, non-volatile Maillard reaction products have been studied
extensively by the Hofmann group. One such compound, N -(1-carboxyethyl)-6-
hydroxymethyl-pyridinium-3-ol, commonly known as pyridinium betaine or
alapyridaine, was isolated and found to have taste-enhancing properties of sweet,
salt and umami perception, but not of bitter and sour tastes (Soldo et al. 2003).
Alapyridaine was fi rst identifi ed in heated sugar/amino acid (glucose/alanine)
mixtures and later extracted from beef bouillon. In isolation it is tasteless, but in
complex mixtures it can signifi cantly modulate taste. It was also found to further
intensify combinations already know to have synergistic effects, such as the
enhancing effect of L -arginine on the salty taste of sodium chloride and of GMP
on the umami taste of MSG.
Within the ripening of soy bean paste (miso), a Maillard-reacted peptide was
thought to be important for the characteristic product fl avour, but the Maillard-
peptide compounds were not isolated nor identifi ed in a study by Ogasawara et al.
(2006a). The same authors also published a paper on the fl avour-enhancing
properties of Maillard reaction products from 1000-5000 Da peptides. Soybean
protein hydrolysates were reacted with xylose and the reaction mixture was
membrane-fractionated to collect the 1000-5000 Da Maillard peptides. They
noted that the Maillard peptide did not have a strong taste in isolation, but
enhanced the fl avour and umami taste of an umami solution and a consommé soup
(Ogasawara et al. 2006b).
A Maillard-type reaction between creatinine and hexoses has been shown to
lead to the formation of N -(1-methyl-4-oxoimidazolidin-2-ylidene)- R -amino
acids that imparted thick-sour, mouth-drying and mouthful sensations in beef
juice but gave no taste sensation in water (Sonntag et al. 2010).
In a recent study of yeast extract, a newly identifi ed compound ( N 2 -(1-
carboxyethyl)guanosine 5′-monophosphate), resulting from a Maillard-like
glycation of GMP, was found to enhance umami taste (Festring and Hofmann

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