Cereal Chem 72:571-577 |
Effect of Certain Surfactants on the Swelling, Solubility, and Amylograph Consistency of Starch.
R. R. Roach and R. C. Hoseney. Copyright 1995 by the American Association of Cereal Chemists, Inc.
The effects of certain mono- and triglycerides and other surfactants on unmodified wheat and corn starch slurries were examined by the Viskograph E. All emulsifiers and surfactants tested caused a lower consistency than the control during the first stage of consistency increase and reduced consistency throughout most of the second stage of consistency increase. Certain monoglycerides went through apparent phase changes, which may have caused them to interact more fully with the starch and reduce consistency below that of the control. When carboxymethylcellulose (CMC) was used to create a background consistency, its consistency could not be deducted from the consistency of a starch plus CMC slurry to obtain the consistency of a starch-only slurry. All monoglycerides tested reduced starch swelling when compared to the control at temperatures of 60-80 C. Monoglycerides with 18 carbons, both saturated and monounsaturated, reduced swelling at 90 C. However, a 10 monoglyceride increased swelling at 90 and 95 C. The increased swelling was also shown by light micrographs and consistency measurements. In general, triglycerides did not affect swelling. All monoglycerides reduced starch solubility compared to that of the control. No triglycerides had an effect on starch solubility. Swelling occurred in two stages, but solubility showed a relatively smooth increase as temperature increased. This suggests that swelling is related to the two stages of consistency increase found with such instruments as the amylograph or viskograph.