High-pressure Sterilization of Ice Nucleation-active Xanthomonas campestris and Its Application to Egg Processing.

Xanthomonas campestris INXC-1 is able to freeze water at a subzero temperature higher than -5°C. High-pressure treatment at 300 MPa and 5°C for 5 min killed the cells without affecting their ice-nucleation activity. Egg white containing the pressurized cells began to freeze with a slight degree of supercooling.

Mutagenicity of methylglyoxal in coffee.

Major carbonyl compounds from a extract of ground roasted coffee beans were identified as 5-hydroxymethylfurfural, acetol, glyoxal, methylglyoxal and diacetyl. Among these carbonyl compounds, methylglyoxal showed considerable mutagenic activity toward Salmonella typhimurium TA100 without S9 mix (around 100,000 revertants/mg). More than 50% of the total mutagenic activity of coffee can be accounted for by the activity of methylglyoxal.