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Research on the effects of high‐intensity ultrasound (HIU) on meat quality properties shows contradictory results. The latter has been sometimes attributed to limited exposure time, not enough to cause cellular modifications. This study evaluated the effect of different exposure times (0, 10, 20, and 40 min) of HIU (37 kHz, 90 W cm−2) on physicochemical properties including; pH, color, tenderness, and microbial counts of two different portions of beef Longissimus lumborum (cranial–caudal). No significant effect of loin portion was observed (p > .05). Ultrasonication time caused a 20.7% toughness reduction of beef (p < .05). However, ultrasonication time also increased hue from 0.62 to 0.76 from red to orange values (p < .05), but it did not affect important coordinates such as a* or C*. Ultrasound caused an increase in the pH from 5.46 to 5.6 (p < .05), but pH was not affected by the time. The highest tenderness was achieved at 40 min of sonication. Significant reductions of mesophiles, psychrophiles, and coliforms were observed after ultrasonication when compared to control (p < .05). The best ultrasonic condition for microbial reduction was at 10 min, when the lowest microorganism counts were achieved, with a subsequent growth when increasing ultrasonication time. Practical Applications High‐intensity ultrasound application appears to be a promising method to increase tenderness in beef. However, optimum time, intensity, and methodology for its application have to be defined, because the variations may affect other quality characteristics such as color or microbial contamination. To find ideal parameter values may help the industry to take decisions on the design of specialized equipment for ultrasonication of meat.

In this study, the effects of ultrasound- (US-) assisted beef marination on consumer perception and the homogeneity of the solute and mass transfer were evaluated. Marinated and US-treated meat samples (40 kHz, 11 W/cm2 for 20, 40, and 60 min, and storing at 4°C for 7 d) were evaluated by a group of consumers using a structured 9-point hedonic scale of satisfaction. The preferences were analyzed with XLSTAT-Sensory® software. The analysis was performed in conjunction with an energy-dispersive X-ray spectroscopic study to evaluate the sodium transference. The perception analysis indicated that the use of US-assisted marination did not increase the beef acceptability. The sonicated samples showed a more homogeneous distribution of sodium. However, traditional marination (TM) stored for 7 d resulted in greater mass transfer than the US-assisted marination without storage.

Beef steaks (L. lumborum and Semitendinosus) were randomly assigned to one of three treatments: 1) No‐ultrasonicated; 2) 16 W/cm2 or 3) 28 W/cm2 ultrasonicated in vacuum bags (VAC). Later, steaks were also randomly packed in either VAC or modified atmosphere (MAP, 25–75%, CO2‐O2). After simulated retail display (SRD, 3°C, 12 h light) for 6 d, High‐intensity Ultrasound (HIU) increased redness and saturation on VAC meat (p < 0.05) and produced an increase on L. lumborum (p < 0.05) but not on Semitendinosus (p > 0.05) shear force. High concentrations of O2 in MAP increased loss of redness (2.83 vs. 2.13 MAP vs. VAC, respectively) and saturation (2.64 vs. 1.99, respectively) during SRD. MAP also increased L. lumborum shear force (4.4 vs. 3.2 kgf, respectively p < 0.001) and lipid oxidation (p < 0.001). HIU may be consider as a strategy to improve beef color on VAC. Moreover, high O2 concentrations on MAP should be used with caution for beef, because of a possible negative impact on oxidative stability and tenderness.Practical applicationsHigh intensity ultrasound on bovine Longissimus lumborum and Semitendinosus appears to be a promising method among the recent techniques for improving color of vacuum packed beef without a negative effect on pH and water holding capacity when applied to fresh meat. Hence, ultrasonication may be considered as a strategy to positively influence the acceptance of vacuum packed beef by final consumers.

Milk and dairy products have a major role in human nutrition, as they contribute essential nutrients for child development. The nutritional properties of dairy products are maintained despite applying traditional processing techniques. Nowadays, so-called emerging technologies have also been implemented for food manufacture and preservation purposes. Low- and high-intensity ultrasounds are among these technologies. Low-intensity ultrasounds have been used to determine, analyze and characterize the physical characteristics of foods, while high-intensity ultrasounds are applied to accelerate particular biological, physical and chemical processes during food product handling and transformation. The objective of this review is to explain the phenomenology of ultrasounds and to detail the differences between low and high-intensity ultrasounds, as well as to present the advantages and disadvantages of each one in terms of the processing, quality and preservation of milk and dairy products. Additionally, it reviews the rheological, physicochemical and microbiological applications in dairy products, such as raw milk, cream, yogurt, butter, ice cream and cheese. Finally, it explains some methodologies for the generation of emulsions, homogenates, crystallization, etc. Currently, low and high-intensity ultrasounds are an active field of study, and they might be promising tools in the dairy industry.

This review describes the mechanism, operation, and recent potential applications of ultrasound in various food systems, as well as the physical and chemical effects of ultrasound treatments on the conservation and modification of different groups of food. Acoustic energy has been recognized as an emerging technology with great potential for applications in the food industry. The phenomenon of acoustic cavitation, which modifies the physical, chemical, and functional properties of food, can be used to improve existing processes and to develop new ones. The combination of ultrasonic energy with a sanitizing agent can improve the effect of microbial reduction in foods and, thereby, their quality. Finally, it is concluded that the use of ultrasound in food is a very promising area of research; however, more research is still needed before applying this technology in a wider range of industrial sectors.

This study aimed to evaluate if high-intensity ultrasound (HIU, 90 W/cm 2 , 37 kHz, 40 min) application in vacuum-packed beef, generated physicochemical changes comparable to those occurring in wet ageing. Steaks were randomly assigned to the following treatments: CON, control meat without HIU nor ageing; HIU, ultrasound for 40 min; A1, meat wet-aged for 5 d; and A2, meat wet-aged for 10 d. After treatment, meat was placed in a shelf-life simulation for 5 d. pH, colour (a*, b*, L* and C*), water-holding capacity (WHC) and shear force were evaluated. HIU promoted higher redness and chroma during shelf life. Ten-day wet ageing tended to increase WHC. Shear force was not different (p > 0.05) after shelf life. Although HIU did not improve tenderization over aged beef for up to 10 d. The improvement of chroma and redness may represent practical advantages over short time ageing. Ultrasonido Versus Maduración Tradicional: Propiedades Fisicoquímicas en Longissimus lumborum de vacuno RESUMEN Este estudio tuvo como objetivo evaluar si la aplicación de ultrasonido de alta intensidad (UAI, 90 W/cm 2 , 37 kHz, 40 min) en carne de vacuno envasada al vacío generaba cambios fisicoquímicos comparables a los que ocurren durante la maduración en húmedo. Los filetes se asignaron al azar a los siguientes tratamientos: CON, carne control sin UAI ni maduración; UAI, ultrasonido durante 40 min; A1, carne madurada en húmedo durante 5 d y A2, carne madurada en húmedo durante 10 d. Después del tratamiento, la carne se colocó en una simulación de vida útil durante 5 d. Se evaluó el pH, color (a *, b *, L * y C *), capacidad de retención de agua (CRA) y fuerza de corte. El UAI promovió mayor enrojecimiento y saturación durante la vida útil. Diez días de maduración en húmedo aumentaron la CRA. La fuerza de corte no se modificó (p > 0.05) después de la vida útil. Aunque el UAI no mejoró el ablandamiento de la carne de res madurada hasta por 10 días bajo las condiciones experimentales, la mejora en la saturación y el enrojecimiento representan ventajas prácticas sobre la maduración de la carne por periodos cortos de tiempo.

High-intensity ultrasound has been reported as a novel technology applied to improve tenderness in beef, pork, lamb and poultry. Its potential benefit has been studied mostly in individual muscles. This study aimed to evaluate the effect of high-intensity ultrasound (HIU, 24 kHz, 12 W/ cm 2 for 15 min) on quality traits of whole rabbit carcases. Twenty rabbit carcases were longitudinally split into two sides along the vertebral column. One side of the carcase was kept as Control and the opposed was vacuum packed and ultrasonicated with a probe HielscherV R UP400St. After treatment and 7 d (2 C) in vacuum packs, m. L. dorsi (LD), Semimembranosus and Semitendinosus were dissected from the carcases to evaluate water holding capacity (WHC), shear force, pH, and colour (L à , a à and b à ). Promising results were observed in LD after ultrasonication. LD shear force was reduced (p < .05) from 13.04 to 11.18 N (control vs. sonicated, respectively). The colour was also modified (p < .05), increasing L à from 46.70 to 48.30 units and increasing b à from 4.70 to 6.10 units (control vs. sonicated, respectively). WHC, was reduced (p < .05) by HIU only in loin. The pH, and a à from LD were not modified by ultrasonication (p > .05). In conclusion, HIU applied to rabbit carcases positively influenced LD characteristics, but no changes were observed in leg muscles under this study conditions. The data suggest that the effect of the HIU treatment on the whole carcase may differ according to the muscles. HIGHLIGHTSHigh intensity ultrasound has been applied to rabbit carcases as a small-scale model for other species. Ultrasonicating vacuum packed carcases of rabbit may lead to different changes of physicochemical characteristics in particular muscles. High-intensity ultrasonication increases L à , a à and tenderness in L. dorsi but it does not affect Semimembranosus-Semitendinosus. High-intensity ultrasound applied to carcases does not have the same effect in all muscles.