EFFECT OF CERTAIN SURFACTANTS ON THE SWELLING, SOLUBILITY AND AMYLOGRAPH CONSISTENCY OF STARCH

The effects of certain mono- and triglycerides and other surfactants o n unmodified wheat and corn starch slurries were examined by the Visko graph E. All emulsifiers and surfactants tested caused a lower consist ency than the control during the first stage of consistency increase a nd reduced consistency throughout most of the second stage of consiste ncy increase. Certain monoglycerides went through apparent phase chang es, which may have caused them to interact more fully with the starch and reduce consistency below that of the control. When carboxymethylce llulose (CMC) was used to create a background consistency, its consist ency could not be deducted from the consistency of a starch plus CMC s lurry to obtain the consistency of a starch-only slurry. All monoglyce rides tested reduced starch swelling when compared to the control at t emperatures of 60-80 degrees C. Monoglycerides with 18 carbons, both s aturated and monounsaturated, reduced swelling at 90 degrees C. Howeve r, a 10 monoglyceride increased swelling at 90 and 95 degrees C. The i ncreased swelling was also shown by light micrographs and consistency measurements. In general, triglycerides did not affect swelling. All m onoglycerides reduced starch solubility compared to that of the contro l. No triglycerides had an effect on starch solubility. Swelling occur red in two stages, but solubility showed a relatively smooth increase as temperature increased. This suggests that swelling is related to th e two stages of consistency increase found with such instruments as th e amylograph or viskograph.