Potential and restrictions of photocentrifugation for determining the emulsion stability of melted spreadable processed cheese

Abstract

A previous study had shown that the method of photocentrifugation could be adapted to monitor emulsion stability of melted spreadable processed cheese (PC) with low content of emulsifying salts (ES). The present study continued the experiments with higher ES content exploring the potential and restrictions of this new approach. The PC containing 40% fat in dry matter and 1.0 or 1.9% w/w ES was manufactured for 5-19 min at 82°C and three different rotational speeds of the cutter. Light transmission was measured during centrifugation of the melted PC in thin cuvettes at 60°C. The transmission profiles were used to characterize emulsion stability. Fat distribution was measured for better interpretation of the centrifugation results. An increase in transmission to ≥20% occurred after different periods of centrifugation at 1200×g. Samples with 1.0% w/w ES showed different particle movements during centrifugation for 150 min. Polydisperse creaming, sedimentation, and distinct zone sedimentation were identified, the latter allowing the calculation of characteristic sedimentation velocities. The PC with 1.9% w/w ES manufactured at a cutter speed of 3000 rpm for 5 min required the maximum acceleration of 2150×g to achieve measurable transmission after 195 min, corresponding to 291 days under normal gravity. These results show the high sensitivity of photocentrifugation proving even little physical changes of the PC matrix. However, this sensitivity restricts the applications to melted spreadable and suboptimal emulsified products.

Interfacial and Emulsion Characteristics of Oil–Water Systems in the Presence of Polymeric Lignin Surfactant

“…42 The dimensionless index was quantified by the clarification at a given separation time divided by the maximum clarification. 43 The dramatic separation of phases is an indication of the instability of emulsions, which results in a larger instability index. The integration graphs were also generated and described as the "creaming rate", which showed the transmitted light in percent over time.…”

“…Simultaneously, near-infrared light of the instrument (λ = 865 nm) was applied to illuminate the samples to determine the instability indices by the included software (SepView 6.0; LUM) . The dimensionless index was quantified by the clarification at a given separation time divided by the maximum clarification . The dramatic separation of phases is an indication of the instability of emulsions, which results in a larger instability index.…”

Sedimentation Dynamics of Colloidal Formulations through Direct Visualization: Implications for Fuel Cell Catalyst Inks

“…Recent advances in analytical centrifugation (AC), employing STEP-technology (Space-Time Extinction Profiles; shown in Figure A), permit direct measurement of sedimentation dynamics of particle systems in a facile manner, with low cost and preparation demands. Monitoring the progression of particles in a centrifugal field is attractive for several applications, such as (a) evaluation of process–structure relationships, (b) comparison of emulsifying properties, , and (c) assessment of emulsion/dispersion stability. , Lately, a handful of studies report the successful use of AC to evaluate ink stability by calculating relative sedimentation times. ,, Collectively, these studies underline the untapped potential of this characterization technique for complex colloids.…”

“…Monitoring the progression of particles in a centrifugal field is attractive for several applications, such as (a) evaluation of process− structure relationships, 13 (b) comparison of emulsifying properties, 14,15 and (c) assessment of emulsion/dispersion stability. 16,17 Lately, a handful of studies report the successful use of AC to evaluate ink stability by calculating relative sedimentation times. 1,2,18 Collectively, these studies underline the untapped potential of this characterization technique for complex colloids.…”

Exhibitive Nano-to-Micron Scale Sedimentation Dynamics of Colloidal Formulations Through Direct Visualization

“…Monitoring the progression of particles in a centrifugal field is attractive for several applications, such as (a) evaluation of processstructure relations, 13 (b) comparison of emulsifying properties, 14,15 and (c) assessment of emulsion/dispersion stability. 16,17 Lately, a handful of studies report the successful use of AC to evaluate ink stability by calculating relative sedimentation times. 1,2,18 Collectively, these studies underline the untapped potential of this characterization technique for complex colloids.…”