Temperature and concentration effects on the flow behaviour of stickwater

F. M. Goycoolea, J. M. Nieblas, L. O. Noriega, I. Higuera-Ciapara

Risultato della ricercapeer review

6 Citazioni (Scopus)

Abstract

Condensed stickwater (SW), a liquid byproduct generated on a large-scale in the fish meal industry, has a high protein content (~ 20% w/w) and non-protein-nitrogen-compounds (NPNCs). Processing of large amounts of SW requires efficient engineering especially where its handling is problematical. To this end, the theological properties of SW were partially investigated by a simple viscometric technique at different levels of concentration of solid matter (6-44.3% w/w) and temperature (26-80°C). The 'power law' coefficient of consistency (K) and flow index (n) were obtained from best-fit lines of angular-velocity vs torque. A genetic linear relationship between ln-K and concentration was appreciated throughout the temperature range studied similar to the characteristic concentration dependence of viscosity documented for globular proteins. The effect of temperature on K was highly dependent upon concentration of total solids. At 6% (w/w) it had a marginal effect as well as at 23.9% (w/w) up to 65°C, yet at 80°C an increase in K was observed; at 44.3% (w/w) the effect of temperature followed an Arrhenius type of behaviour, seen as decreasing ln-K values as temperature increased (activation energy = 8.53 x 103 J). Although non-Newtonian behaviour (pseudoplastic or 'shear-thinning' with n < 0.85) was common to all SW solutions, it was accentuated at ca. 24% (w/w; n < 0.43), and persisted to low total solids content (6% w/w) throughout all temperatures. Above 50°C and 24% (w/w), the n index increased monotonically with both variables. Experiments at steady-shear over prolonged periods (up to 2 h), revealed typical thixotropic behaviour as concentration and temperature of SW dispersions increased. The complex theological behaviour is suggested to stem from irreversible protein denaturation probably involving soluble sarcoplasmic muscle proteins as well as structural breakdown of large colloidal species.

Lingua originaleEnglish
pagine (da-a)217-225
Numero di pagine9
RivistaBioresource Technology
Volume59
Numero di pubblicazione2-3
DOI
Stato di pubblicazionePublished - 1 feb 1997
Pubblicato esternamente

Fingerprint

Entra nei temi di ricerca di 'Temperature and concentration effects on the flow behaviour of stickwater'. Insieme formano una fingerprint unica.

Cita questo