Abstract This work aimed to present aspects related to the use of ultrasound in fruit and vegetable processing, such as the functioning of the method, effects on food, applications, sensory aspects and consumer perception. Changes in eating habits and the search for well-being reflect the increased demand for natural foods, such as fruits and vegetables. These foods may undergo microbiological changes along the production chain, and it is necessary to adopt Good Agricultural Practices (GAP), even as handling and technological processes of conservation to ensure the quality of the final product. Ultrasound is an emerging technology applied in fruit and vegetable processing that is related to improvements in quality and preservation. The basic principle of ultrasound is acoustic cavitation, which involves the growth and collapse of bubbles during periods of rarefaction and compression, causing chemical, physical, and mechanical changes in food. These changes are associated with the inactivation of microorganisms, enzymes, as well as the removal of residues and improvements in the physical-chemical quality and accessibility of bioactive compounds. In addition, the application of this method can have good acceptability by consumers looking for more natural foods and that are submitted to processes that does not cause environment impact.

Resumo Este trabalho objetivou apresentar aspectos relacionados à utilização do ultrassom no processamento de frutas e hortaliças, como o funcionamento do método, os efeitos no alimento, as aplicações, os aspectos sensoriais e a percepção dos consumidores. As mudanças dos hábitos alimentares e a busca do bem-estar refletem no aumento da procura por alimentos naturais, como as frutas e as hortaliças. Estes alimentos podem sofrer alterações microbiológicas ao longo da cadeia produtiva, sendo necessária a aplicação de boas práticas agrícolas e de manipulação, e processos tecnológicos de conservação para a garantia da qualidade do produto. O ultrassom é uma tecnologia emergente aplicada no processamento de frutas e hortaliças que está relacionada a melhorias na qualidade e preservação. O princípio básico do ultrassom é a cavitação acústica, que envolve o crescimento e colapso de bolhas durante períodos de rarefação e compressão, causando alterações químicas, físicas e mecânicas no alimento. Essas alterações estão relacionadas à inativação de micro-organismos e de enzimas, à remoção de resíduos e às melhorias na qualidade físico-química, e à acessibilidade de compostos bioativos. Além disso, a aplicação deste método pode ter boa aceitabilidade pelos consumidores, que procuram alimentos mais naturais e submetidos a processos que não causem impacto ambiental.

The expansion of land use for agriculture is among the main reasons for the reduction of natural grasslands around the world, and little is known about the recovery potential of original native grassland vegetation from seed banks. The aim of this study was to assess the seed bank potential of grassland areas with or without history of cultivation in southern Brazil. Specifically, we aimed at evaluating if agricultural use allowed for the persistence of species typical of natural grasslands in soil seed banks. We analyzed seed banks in two areas with a history of cultivation and in two natural grasslands. Samples were collected in spring and autumn in order to assess transient and persistent components, and were characterized by density, richness, presence of exotic species and relationship between seed bank and established vegetation. Both richness and density were high; we found a total of 114 species and a mean density of 61,796 seedlings/m2 for all four areas in the spring sampling. In the natural grasslands, the dominant species of established vegetation were mostly absent from the soil seed bank. Our study indicates that the seed bank is of little relevance for the recovery of typical grassland vegetation after disturbance.