MIXOGRAPH STUDIES .6. COMBINED EFFECTS OF CHARGE (PH), ACTIVATED DOUBLE-BOND COMPOUNDS, AND OXIDANTS ON DOUGH MIXING PROPERTIES

The effects of activated double-bond compounds, fast-acting oxidants, and pH (singly and in combination) on dough overmixing (breakdown) wer e investigated by mixogram curve analysis. Breakdown of flour-water an d full-formula doughs was quantitated by measuring mixogram curve widt h at 3 min after the point of minimum mobility (optimum mixing). The e ffect of activated double-bond compounds was more pronounced with flou r-water doughs than it was with full-formula doughs, although their ef fect was still clearly demonstrable in mixograms. Fast-acting oxidants , such as KIO3, were shown to oxidize a compound in the gluten-prime s tarch fraction and thereby cause an accelerated breakdown of the mixog ram tail (overmixing). Stability of flour-water doughs to overmixing, as measured by the mixogram tail width, gave a sigmoidal curve as a fu nction of dough pH. Tail widths were narrow at low pH and wide at high pH. There was a plateau in the curve near the pH of flour-water slurr ies (approximately 6.0). Compounds that affected curve stability were most effective in the plateau region. Strong flours were more resistan t to changes in pH than were weak flours.