The shear viscosities of xanthan batch fermentation broths obey a power‐law relation τ = K (P)[ẏ]^N(P), where the power‐law parameters are functions of xanthan concentration P. within the shear rate range of 1.15 to 384.0 sec⁻¹. Cell‐free solutions prepared from these samples exhibit the same values of K and N as the corresponding cell‐bearing broth. Further, in the course of the fermentation time, t, it was found that K(P) and N(P) were related by an equation of the form ln K[P(t)] = ln τ₀ – N[P(t)]·ln ẏ₀, leading to a dimensionless power‐law equation valid over the entire fermentation: (τ/τ₀) = (ẏ/ẏ₀)^N[P(t)]. The resulting power‐low from[(τ/τ₀) = [ẏ/ẏ₀]^N(t)] indicates that all related samples will exhibit power‐low plots passing through the common point, (τ₀γ₀). These equations have previously been observed with other polysaccharide solution. They are also shown here to be applicable to the pullulan fermentation data of Leduy et at. The parameter K is related to polymer concentration (P) with the correlation K = A P^B, where B = 1.75 ± 0.25 for xanthan solutions. With X(t), S(t), and P(t) available from paper I, the correlations of this paper (hereafter referred to as II) [K(t) = f(P)(t) and N(t) = g(K(t))] provide a predictive description of the shear viscosity evolution of polysaccharide‐producing fermentation broths.

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