High isostatic pressure and thermal processing of gal fruit (Euterpe oleracea Martius): Effect on pulp color and inactivation of peroxidase and polyphenol oxidase

Autor(es)

Tiberio de Jesus, Ana Laura ^[1] ; Leite, Thiago Soares ^[1] ; Cristianini, Marcelo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Sch Food Engn FEA, Dept Food Technol DTA, UNICAMP, Monteiro Lobato 80, POB 6121, BR-13083862 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Food Research International; v. 105, p. 853-862, MAR 2018.
• Citações Web of Science: 0

Resumo

The present study evaluated the effect of high isostatic pressure (HIP) on the activity of peroxidase (POD) and polyphenol oxidase (PPO) from agai. Agai pulp was submitted to several combinations of pressure (400, 500, 600 MPa), temperature (25 and 65 degrees C) for 5 and 15 min. The combined effect of HIP technology and high temperatures (690 MPa by 2 and 5 min at 80 degrees C) was also investigated and compared to the conventional thermal treatment (85 degrees C/1 min). POD and PPO enzyme activity and instrumental color were examined after processing and after 24 h of refrigerated storage. Results showed stability of POD for all pressures at 25 degrees C, which proved to be heat-resistant and baro-resistant at 65 degrees C. For PPO, the inactivation at 65 degrees C was 71.7% for 600 MPa after 15 min. In general, the increase in temperature from 25 degrees C to 65 degrees C reduced the PPO relative activity with no changes in color. Although the thermal treatment and the HIP (690 MPa) along with high temperature (80 degrees C) reduced the PPO relative activity, and relevant darkening was observed in the processed samples. Thus, it can be concluded that POD is more baro-resistant than PPO in acai pulp subjected to the same HIP processing conditions and processing at 600 MPa/65 degrees C for 5 min may be an effective alternative for thermal pasteurization treatments. (AU)

• Processo FAPESP: 15/01570-0 - Processamento de polpa de açaí (Euterpe oleracea Martius) por tecnologia de alta pressão isostática
• Beneficiário: Ana Laura Tibério de Jesus
• Modalidade de apoio: Bolsas no Brasil - Doutorado