Abstract:

Taro protein isolate was studied for its rheological properties and characterized by ultraviolet and fluorescence
spectroscopy at different pH conditions. The results showed that pH had an obvious effect on denaturation and aggregation
of taro protein isolate. At pH values close to the isoelectric point, taro protein isolate aggregates had higher apparent
viscosity, obvious hysteresis, and higher gelling temperature (Tgel) and gel storage modulus (G’). At pH 8.0 (greater than
taro proteins isoelectric point), disaggregation, conformational unfolding, lower apparent viscosity, reduced hysteresis, and
decreased Tgel and gel G’ of taro protein isolate were observed. Along with an increase in solution pH, intersection of G’ and
G” was shifted in the high frequency direction and disappear gradually. At pH 7.0, the ultraviolet absorption peak occurred
at 284 nm, and the maximum fluorescence excitation and emission wavelengths were 289.7 nm and 330.3 nm, respectively.

Key words: taro protein isolate, rheology, ultraviolet, fluorescence, isoelectric point