Acoustic cavitation for agri-food applications: Mechanism of action, design of new systems, challenges and strategies for scale-up

Acoustic cavitation, an intriguing phenomenon resulting from the interaction of sound waves with a liquid medium, has emerged as a promising avenue in agri-food processing, offering opportunities to enhance established processes improving primary production of ingredients and further food processing. This comprehensive review provides an in-depth analysis of the mechanisms, design considerations, challenges and scale-up strategies associated with acoustic cavitation for agri-food applications. The paper starts by elucidating the fundamental principles of acoustic cavitation and its measurement, delving then into the diverse effects of different parameters associated with, the acoustic wave, mechanical design and operation of the ultrasonic system, along with those related to the food matrix. The technological advancements achieved in the design and set-up of ultrasonic reactors addressing limitations during scale up are also discussed. The design, engineering and mathematical modelling of ultrasonic equipment tailored for agri-food applications are explored, along with strategies to maximize cavitation intensity and efficiency in the application of brining, freezing, drying, emulsification, filtration and extraction. Advanced US equipment, such as multi-transducers (tubular resonator, FLOW:WAVE®) and larger processing surface areas through innovative designing (Barbell horn, CascatrodesTM), are one of the most promising strategies to ensure consistency of US operations at industrial scale. This review paper aims to provide valuable insights into harnessing acoustic cavitation's potential for up-scaling applications in food processing via critical examination of current research and advancements, while identifying future directions and opportunities for further research and innovation.

Impact of ultrasound processing on alternative protein systems: Protein extraction, nutritional effects and associated challenges

Proteins from alternative sources including terrestrial and aquatic plants, microbes and insects are being increasingly explored to combat the dietary, environmental and ethical challenges linked primarily to conventional sources of protein, mainly meat and dairy proteins. Ultrasound (US) technologies have emerged as a clean, green and efficient methods for the extraction of proteins from alternative sources compared to conventional methods. However, the application of US can also lead to modifications of the proteins extracted from alternative sources, including changes in their nutritional quality (protein content, amino acid composition, protein digestibility, anti-nutritional factors) and allergenicity, as well as damage of the compounds associated with an increased degradation resulting from extreme US processing conditions. This work aims to summarise the main advances in US equipment currently available to date, including the main US parameters and their effects on the extraction of protein from alternative sources, as well as the studies available on the effects of US processing on the nutritional value, allergenicity and degradation damage of these alternative protein ingredients. The main research gaps identified in this work and future challenges associated to the widespread application of US and their scale-up to industry operations are also covered in detail.

Long-term effects in ovaries of the adult mice following exposure to monosodium glutamate during neonatal life--a histological study

Monosodium Glutamate (MSG) has been in use since long as a flavour enhancing substance. Its widespread use has also earned it a bad name to be harmful for human health. It had been incriminated in wide range of effects comprising retinal degeneration, metabolic disorders, endocrinal disorders including reduced fertility rate in both in both sexes in mice. However there were many contradicting views too, which have prompted us to undertake the present study. For our study eight female newborns of Swiss Albino mice were injected subcutaneously with MSG (2mg / gm of body wt. in a dilution 40 mg of per ml. of distilled water) on completion of 2nd, 4th, 6th, 8th and 10th day of life. Another five mice pups were injected with same volume of distilled water and taken as control. On completion of 75 days the mice were sacrificed of, ovaries were collected through dissection, 5 micron thick sections were cut and stained by H and E and PAS stain and studied under light microscope. It was observed from the quantitative analysis of the ovarian tissue that there was increase in the number of the primary follicle without increase in number of Graffian follicle in the experimental group.

Long term effects of monosodium glutamate on spermatogenesis following neonatal exposure in albino mice--a histological study

Monosodium glutamate (MSG), popularly known as Azinomoto has been in use since long as a flavour enhancing substance. Its widespread use has also earned it a bad name as hazardous for human health. It has been incriminated to cause wide range of effects comprising retinal degeneration, metabolic disorders, endocrinal disorders including reduced fertility rate in both male and female experimental mice and rats following neonatal exposure. However there are many contradicting views too regarding the above effects which have prompted us to undertake the present study. In our study seven newborns of Swiss Albino mice were injected subcutaneously with MSG (2 mg/gm ofbody wt. in a dilution 40 mg of per ml. of distilled water) on completion of 2nd, 4th, 6th, 8th and 10th day of life. Similar number of controls were injected with same volume of distilled water. Testes were obtained through dissection on completion of 75 days of life. 5 micron thick sections were cut, stained by H.E. and Heidenhain's Iron Haematoxylin and studied under light microscope. It was observed from the quantitative analysis of the seminiferous tubules that there was increase in the number of the pachytene stage of primary spermatocyte in the experimental group as compared to that of the control animals of corresponding age.