Effect of storage time on physical properties of sonocrystallized all-purpose shortening

Crystallization of lipids and lipid emulsions treated by power ultrasound: A review

The actual food system with fat is always complex and fat crystal and fat crystal networks have important effects on the physical properties of food. Recently, power ultrasound (PU) had been widely recognized as an auxiliary technology of fat crystallization to modify food properties. This review expounded on the mechanism of ultrasonic crystallization, and summarized effects of various factors in the process of ultrasonic treatment on fat crystallization. Based on the above, combined with the application of ultrasound in emulsions, the ultrasonic fat crystallization effect in the emulsion system was judged and described. Research results indicated that PU could shorten the induction time of crystallization, accelerate the formation of crystal nuclei, and change the polymorphism of fat crystals. The product treated by PU formed smaller and more uniform crystals to produce a more viscoelastic fat crystal network. In emulsion systems, ultrasonic treatments showed the same effect, but the effect of ultrasonic crystallization on the emulsion stability was different due to fat crystals in different emulsion systems. Meanwhile, the importance of ultrasonic crystallization in lipid emulsions was emphasized, thus ultrasonic crystallization had great potential in emulsion systems.

Development of an optical flow through detector for bubbles, crystals and particles in oils

The characterisation of bubbles or particles in an oil poses some unique challenges. In contrast to water solutions, the use of electrochemical detection approaches is more difficult in an oil. However, optical sensing systems have considerable potential in this area. Here we use a flow through channel approach and monitor the light propagation through this structure in an optical transmission sensor arrangement (OTS). This simple approach is demonstrated to be useful at detecting bubbles produced in the oil as a result of cavitation induced by high intensity ultrasound (HIU). The optical technique is shown to have an analytical basis. Bubble detection from an operating HIU source is shown to depend on position of the sensor with respect to the source. Critically, the bubble population can be followed for extended time periods after the ultrasonic source has been terminated. The detection of crystals is also demonstrated. Hence, this technique is ideal for the study of the effects of HIU on oils as they crystallise over extended time periods.

Ultrasound-assisted gelation of β-carotene enriched oleogels based on candelilla wax-nut oils: Physical properties and in-vitro digestion analysis

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Candelilla wax mix with peanut, pine nut and walnut oils can form oleogels.

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Ultrasound increased G’, G’’, firmness and oil-binding capacity of oleogels.

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Ultrasound treatment improved the protection of β-carotene in oleogels.

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Ultrasound reduced the amount of β-carotene released during intestinal digestion.

This study investigated the effects of high-intensity ultrasound (HIU, 95 W, 10 s) on the physical properties, stability and in vitro digestion of β-carotene enriched oleogels. Candelilla wax (3 wt%) and nut oils (peanut, pine nut and walnut oil) with or without β-carotene were used to form oleogels. HIU improved the storage modules (G’) of peanut, pine nut and walnut oleogels without β-carotene from 11048.43 ± 728.85 Pa, 38111.67 ± 11663.98 Pa and 21921.13 ± 1011.55 Pa to 13502.40 ± 646.54 Pa, 75322.47 ± 9715.25 Pa and 48480.97 ± 4109.64 Pa, respectively. Moreover, HIU reduced oil loss of peanut, pine nut and walnut oleogels without β-carotene from 23.98 ± 2.58%, 17.14 ± 0.69% and 24.66 ± 1.57% to 17.60 ± 1.10%, 13.84 ± 0.74% and 18.72 ± 3.47%, respectively. X-ray diffraction patterns showed that HIU did not change the form of the crystal (β-polymorphic and β’-polymorphic) but increased the crystal intensity. Polarized light microscope images indicated that all oleogels showed more visible crystals after HIU. After 120 d of storage, HIU decreased the degradation of β-carotene for peanut oil and walnut oil samples (the contents of β-carotene in peanut and walnut oleogels without HIU after 120 d of storage were 897 ± 2 μg/g and 780 ± 1 μg/g, respectively, and those of sonicated samples were 1070 ± 4 μg/g and 932 ± 1 μg/g, respectively). Furthermore, HIU reduced the release of β-carotene in intestinal digestion. In conclusion, HIU could improve the functional properties of wax-nut oils oleogels and their β-carotene enriched oleogels.