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The thermal denaturation of the naturally occurring lactoferrin in raw bovine whole milk has been measured over a range of temperatures from 65 to 121 °C for holding times from 2 up to 300 s designed to mimic heating processes used in the food manufacturing industry. Data were generated by heat treatments of raw whole milk from two different sources, New Zealand (NZ) and China, and with lactoferrin at two different levels of naturally occurring iron saturation. Denaturation rates for lactoferrin in the Chinese-sourced milk samples were at least two-fold greater than lactoferrin in the NZ milk over the temperature range 65–80 °C. At 85 °C rates of denaturation were the same although more than 80-fold greater than at 65 °C whereas, at 95 °C, lactoferrin in the NZ milk denatured at twice the rate of that in the Chinese milk. The differences in denaturation rates up to 80 °C likely reflected the greater heat stability of the more iron-saturated NZ milk samples. From these data, a combined kinetic and Arrhenius-based model has been developed and validated that allows calculation of native lactoferrin retained after thermal processing at any temperature-time combination in the experimental range (65–95 °C). This model should have applicability in the evaluation of existing processes and for the design of processes to improve the retention of lactoferrin during food manufacture. • A kinetic model validated for the thermal denaturation of lactoferrin in raw milk. • Loss of lactoferrin with increasing time and temperature over the range 65–95 °C. • The iron saturation of lactoferrin in Chinese milk is lower than those in NZ milk. • Heat stabilities for lactoferrin in Chinese milk were lower than those in NZ milk up to 85 °C. [ABSTRACT FROM AUTHOR]

The adhesion of frozen products such as dairy, water, and juices to industrial metallic surfaces is a major source of inefficiency in the food processing industry. There are different methods developed to quantify ice adhesion strength, but these methods tend to be incomparable due to a combination of tensile and shear force effects. Additionally, these methods usually involve ex-situ freezing which introduced additional experimental errors and prevent cycling of measurements. This paper proposes a new quantitative tensile force technique to characterise the tensile adhesion strength of frozen products to surfaces with less effects from the shear component of force. The in-situ freezing experimental set-up is presented along with case studies performed with commercially available milks in New Zealand to illustrate the benefits and limitations of the method. Results from this technique are not representative of the true ice adhesion strength due to effects of stress concentrations and the use of surfactants. However, this technique shows promise for comparison of the degree of icephobicity for different surfaces. • A method of tensile ice adhesion strength measurement with in-situ- ice formation was proposed. • Method enables comparison of frozen products adhesion strength of different samples. • This frozen product adhesion method is designed to be closer to the real-world conditions of Individual Quick Freezing. • An increase in the fat content in milk shows increased adhesion strength to the same stainless steel substrate. [ABSTRACT FROM AUTHOR]