APPLICATION OF ULTRASOUND IN ORANGE-CARROT JUICE CONSERVATION
Name: BÁRBARA MORANDI LEPAUS
Publication date: 18/03/2019
Advisor:
Name |
Role |
|---|---|
| JACKLINE FREITAS BRILHANTE DE SÃO JOSÉ | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| ANA CRISTINA NASCIMENTO CHIARADIA | Internal Examiner * |
| ÉRICA AGUIAR MORAES | Internal Alternate * |
| GERALDA GILLIAN SILVA SENA | External Alternate * |
| JACKLINE FREITAS BRILHANTE DE SÃO JOSÉ | Advisor * |
Summary: Ultrasound technology is an alternative to pasteurization juice preservation, aiming at minimizing the nutritional and physical-chemical damages observed during traditional thermal processing. The objective of this study was to evaluate the effect of ultrasound on the microbiological, physical-chemical, rheological and sensorial quality of blend orange-carrot juice. Samples of juices were submitted to pasteurization treatments at 90 ° C for 30 seconds and 40 kHz ultrasound at times of 5 and 10 minutes at temperatures of 40, 50 and 60 ° C. Untreated juice samples were considered control. Samples were stored at 7 ± 1 ° C for 22 days and over the course of the storage period, the analyses were conducted. After the evaluation of the results of these analyses, the treatments with ultrasound at 60 ° C for 5 and 10 minutes were selected, in addition to the natural juice without treatment and pasteurized, to perform the sensorial analysis. Higher reductions were obtained after ultrasonic treatment at 60 ° C for 10 minutes for aerobic mesophiles, yeasts, molds, and coliforms at 35 ° C. All the conditions maintained pH, titratable total acidity, soluble solids, total carotenoids, vitamin C, phenolic compounds and antioxidant activity after treatment. Ultrasound treatments increased color parameters and turbidity. During storage, there was a reduction in pH, titratable total acidity, total soluble solids, vitamin C, phenolic compounds, antioxidant activity, and turbidity. It was observed an increase in the content of total carotenoids and in the parameters of color L*, a*, and c*, as well as reduction of hue and b*. Ultrasound treatments at 60 ° C for 5 and 10 minutes delayed the sedimentation process. Optical microscopy showed that increasing the time and temperature of treatment caused more damage to cell structures. The sample treated with ultrasound at 60 ° C for 5 minutes was evaluated statistically equal to the pasteurized sample in the sensorial analysis. Ultrasound treatment for 10 minutes at 60 ° C received the lowest scores for the assessed attributes.
