The need to eliminate trans-fatty acids from foods' formulation resulted in the exploration of new lipid sources and alternative processing conditions that will improve the physicochemical characteristics and nutritional qualities of lipid-based foods. In general, the physicochemical characteristics of lipid networks depend on the microstructure and crystallization behavior of the system. The objective of this work was to use high intensity ultrasound (HIU) as an additional processing condition to alter the crystallization behavior of a lipid model system (anhydrous milk fat). Results show that HIU application not only decreases the induction time of crystallization (faster crystallization) at a constant crystallization temperature, but also generates smaller crystals. In addition, higher viscosities are obtained when samples are crystallized after HIU application. The degree of supercooling, ultrasound application settings and a combination of both parameters influence the degree of ultrasound effect on the crystallization behavior.

Ultrasound has been used for the last 50 y in different processing applications. Depending on the power and frequency of the sound waves, ultrasound techniques can be classified in different categories. Low-intensity ultrasound uses high frequencies in the range of 100 kHz to 10 MHz and is mostly used for therapeutic purpose (frequencies between 1 and 10 MHz) and to passively monitor the characteristics of materials (frequencies between 100 kHz and 10 MHz). High-intensity ultrasound (HIU), on the other hand, uses lower frequencies in the range of 20 to 100 kHz and it is commonly used for cleaning, disrupting, and restructuring materials. The objective of this study is to evaluate the effect of HIU on functional properties of anhydrous milk fat (AMF), palm kernel oil (PKO), and an all-purpose shortening (Sh). Results from this research shows that HIU induced primary and secondary nucleation in the lipid, generating smaller crystals and as a consequence harder materials. HIU affected hardness more efficiently when applied at higher crystallization temperatures (26 and 28 degrees C) as shown for AMF data, and when the sonication was applied after the first crystals were formed as observed for PKO and Sh systems. In addition to changes in hardness, AMF and Sh networks obtained after sonication were characterized by a steeper and sharper melting profile. This research shows that HIU can be used as an additional processing tool to tailor the functional properties of lipids with the potential to be used in the processing of trans-free shortenings.

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The objective of this study was to evaluate the effect of oil addition (10, 20 and 40% of oil in water) on saltiness perception as a function of NaCl concentration. A sensory panel (n = 20) was selected from the local community and trained to taste saltiness intensity using magnitude estimation. Data obtained were fitted to the Stevens’ power law. As expected, saltiness intensity increased as [NaCl] in the aqueous phase ([NaCl]aq) increased, for a constant type of sample. All types of samples (0, 10, 20 and 40% oil‐in‐water emulsions) were well fitted to the Stevens’ power law with exponent values of 0.87, 0.76, 0.66 and 0.47 for the 0, 10, 20 and 40% oil‐in‐water emulsions, respectively. This is the first research that reports exponential values for saltiness perception in the presence of an oil phase. This research also shows that saltiness perception is driven by a combination of processes that include [NaCl]em and the presence of an oil phase. Practical Applications This research contributes to the understanding of the effect of oil addition on saltiness perception for a range of NaCl concentration. This knowledge will help food scientist in the development of foods with reduced amount of sodium while maintaining the sensory properties of their product.

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