Data/hora: 03/06/2024 04:07:14

Biblioteca(s): | Embrapa Agroindústria de Alimentos.
Data corrente: | 18/05/2023
Data da última atualização: | 11/12/2023
Autoria: | LIMA, M A.; CUNHA, R. L. da; TONON, R. V.; ROSENTHAL, A.
Afiliação: | MARIAH ALMEIDA LIMA, UFRRJ; ROSIANE LOPES DA CUNHA, UNICAMP; RENATA VALERIANO TONON, CTAA; AMAURI ROSENTHAL, CTAA.
Título: | Impact of microfluidization and ultrasonication on the properties of sodium alginate-based pink pepper essential oil nanoemulsion.
Ano de publicação: | 2023
Fonte/Imprenta: | In: CONFERÊNCIA INTERNACIONAL DE PROTEÍNAS E COLOIDES ALIMENTARES, 9., 2023, Rio de Janeiro. Anais... Campinas, Galoá, 2023.
Idioma: | Inglês
Notas: | Poster 157698. Eixo temático: Colóides para filmes comestíveis. CIPCA.
Conteúdo: | Sodium alginate is a natural polysaccharide, mainly derived from brown algae species, and a proper raw material to be used in the production of edible films and coatings. Nanoemulsions incorporating certain essential oils, such as pink pepper essential oil (Schinus terebinthifolius Raddi), can be used in edible coatings and films to provide antimicrobial and antioxidant characteristics, aiming to improve the shelf life of several kinds of foods. Nanoemulsions are commonly produced using high energy methods, which involve the use of large amounts of disruptive forces that reduce bigger droplets into smaller ones using mechanical forces such as shear, compression, or cavitation, breaking down the high interfacial tension between oil and water. The aim of this study was to evaluate the effects of two high-energy methods on droplet size distribution, polydispersity, and droplet morphology of nanoemulsions based on sodium alginate-based pink pepper essential oil nanoemulsion. First, to prepare a pre-emulsion or coarse emulsion, sodium alginate (1.0% w/v) was dissolved in ultrapure water at 70 °C under magnetic stirring. Afterwards, pink pepper essential oil (1.0% w/v) and Tween 80 (ratio 1:1 in relation to the essential oil) were incorporated into the sodium alginate solution using a T18 Digital Ultra Turrax Mixer (IKA) operating at 13,000 rpm for 5 minutes. The two different high-energy processes used to obtain nanoemulsions were ultrasound (US) and microfluidization (MF). Ultrasound device operated with a frequency of 20 kHz and power of 350 W for 5 minutes, while microfluidizer LM20 was used at 15,000 psi for 5 cycles. Droplet size distribution and polydispersity values (PDI) were attained from dynamic light scattering (DLS), while microscopy was obtained with 100x magnification. Droplet size distribution showed that both processes reduced the droplet size to 69?406 nm (US) and 57?3378 nm (MF), showing bimodal distribution and high PDI values (0.380-0.489). Such a heterogeneity in the droplet size may favor the destabilization of the nanoemulsion by coalescence or Ostwald ripening phenomena. Bimodal distribution and high PDI values may be the result of the formation of sodium alginate agglomerates, observed in optical microscopy. These agglomerates can appear as an effect of the degradation of the sodium alginate caused by the phenomena of heating and cavitation, promoted by both processes (ultrasound and microfluidization). Therefore, the high-energy processes proved to be efficient in reducing the droplet size for the formation of the nanoemulsion, but, a better control of the temperature of the processes is necessary to avoid the degradation of the sodium alginate, thus resulting in a more stable nanoemulsion.
Palavras-Chave: | High-energy methods; Nanoemulsion; Pink pepper essential oil.
Categoria do assunto: | --
Registro original: | Embrapa Agroindústria de Alimentos (CTAA)
Exemplares: | CTAA - (15496-1) - UPC - RA - DD -  -  -  - DIS