Evidence of the glycation and denaturation of LTP1 during the malting and brewing process

The influence of malting and brewing processes on the chemical and structur al modifications occurring on LTP1 was investigated by mass spectrometry an d circular dichroism. Proteins were first purified from malt, and samples w ere collected at various steps of beer processing performed on two barley c ultivars. The levels of LTP1 found in malt were not significantly different from the amounts in barley seed. However, in malt, both LTP1b, a post-tran slational form of LTP1, and a third isoform named LTP1c were isolated. More over, both of these proteins were found to be heterogeneously glycated but still exhibited an a-helix structure. Both glycated LTP1 and LTP1b were rec overed during mashing. It was also shown that glycated LTP1 was unfolded du ring heat treatment of wort boiling, which is in agreement with the denatur ed form previously isolated from beer.