The effect of dual-frequency ultrasound on synergistic Sonochemical oxidation to degrade aflatoxin B1.

This study investigated the degradation of aflatoxin B1 (AFB1) in food by using dual-frequency ultrasound (DFUS) and the effects of sonochemical oxidation on the efficacy. It was found that the degradation of AFB1 by bath ultrasound (BU), probe ultrasound (PU), and DFUS were all consistent with first-order kinetics. The use of DFUS significantly increased the AFB1 degradation to 91.3%, and compared with BU and PU, it increased by about 177.0% and 61.5% after 30 min treatment. DFUS could generate a synergistic effect to accelerate the generation of free radicals, which promoted sonochemical oxidation to degrade AFB1. It could be speculated that hydroxyl radical (·OH) probably acted a dominant part in the AFB1 degradation by DFUS, and the hydrogen atoms (·H) might also are contributed. These results indicated that DFUS was an effective method of AFB1 degradation.

Effect of ultrasound on functional properties, flavor characteristics, and storage stability of soybean milk.

The effects of different ultrasound treatments (20 kHz at 400 W for 0 to 9 min) on the functional properties, flavor characteristics, and storage stability of soybean milk at 4 °C were investigated. Results indicated that non-sonicated soymilk had the maximum particle size D4, 3 of 2.47 ± 0.47 µm, while 9 min high intensity ultrasound (HIU) decreased D4, 3 to 0.44 ± 0.01 µm. 9 min of HIU decreased the total number of microorganisms in soymilk from 4.51 to 3.95 Log (CFU/mL). Moreover, 9 min HIU increased the absolute value of ζ-potential from 36.43 to 34.13 mV. Turbiscan test showed that 9 min HIU decreased the instability index of soymilk from 0.78 to 0.65. Furthermore, sensory analysis, electronic nose, electronic tongue, and gas chromatography-mass spectrometry showed that 7 min HIU decreased the content of aldehydes, furans, ketones, and alcohols by 52.09%, 75.01%, 56.79%, and 57.27%, respectively.

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

This study investigated the effects of high-intensity ultrasound (HIU, 95 W, 10 s) on the physical properties, stability and in vitro digestion of ß-carotene enriched oleogels. Candelilla wax (3 wt%) and nut oils (peanut, pine nut and walnut oil) with or without ß-carotene were used to form oleogels. HIU improved the storage modules (G') of peanut, pine nut and walnut oleogels without ß-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 ß-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 (ß-polymorphic and ß'-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 ß-carotene for peanut oil and walnut oil samples (the contents of ß-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 ß-carotene in intestinal digestion. In conclusion, HIU could improve the functional properties of wax-nut oils oleogels and their ß-carotene enriched oleogels.