TY - JOUR
T1 - Evaluation of freeze crystallization on pomegranate juice quality in comparison with conventional thermal processing
AU - Orellana-Palma, Patricio
AU - Guerra-Valle, María
AU - Gianelli, María Pía
AU - Petzold, Guillermo
N1 - Publisher Copyright:
© 2021
PY - 2021/6
Y1 - 2021/6
N2 - The objective of the present study was to evaluate the potential of freeze crystallization (FC) as concentration technology for pomegranate juice. By comparing with conventional thermal treatment (evaporation), the effect on quality parameters (physicochemical properties, bioactive compounds, antioxidant activity, and aromatic profile) at three cycles was investigated. In the last cycle, the results showed that both FC and evaporation technologies, concentrate similar total soluble solids (≈48 °Brix). However, FC maintained a comparable color to the initial sample (red color), while the evaporated samples presented a browning color. FC efficiently retained higher bioactive compound concentration than heat treatment (50 °C), with values close to 87%, 71%, 69% and 67% for total polyphenol, anthocyanin, tannin, and flavonoid content, respectively. A similar behavior, with highest values in FC, was observed in the antioxidant capacity, since FC resulted in an increase of 5.19, 5.12, 5.29 and 4.05-fold versus 3.11, 3.60, 3.87 and 1.97-fold in relation to the initial value, for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) (ABTS), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays, respectively. In aromatic profile, FC allowed preservation of volatile compounds from the fresh juice. Instead, heat treatment only retained 68% of the volatiles components present in the initial sample. Therefore, compared with evaporation, our results suggest that FC is a potential alternative as non-thermal technology to preserve diverse and interesting components from fresh juice.
AB - The objective of the present study was to evaluate the potential of freeze crystallization (FC) as concentration technology for pomegranate juice. By comparing with conventional thermal treatment (evaporation), the effect on quality parameters (physicochemical properties, bioactive compounds, antioxidant activity, and aromatic profile) at three cycles was investigated. In the last cycle, the results showed that both FC and evaporation technologies, concentrate similar total soluble solids (≈48 °Brix). However, FC maintained a comparable color to the initial sample (red color), while the evaporated samples presented a browning color. FC efficiently retained higher bioactive compound concentration than heat treatment (50 °C), with values close to 87%, 71%, 69% and 67% for total polyphenol, anthocyanin, tannin, and flavonoid content, respectively. A similar behavior, with highest values in FC, was observed in the antioxidant capacity, since FC resulted in an increase of 5.19, 5.12, 5.29 and 4.05-fold versus 3.11, 3.60, 3.87 and 1.97-fold in relation to the initial value, for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) (ABTS), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays, respectively. In aromatic profile, FC allowed preservation of volatile compounds from the fresh juice. Instead, heat treatment only retained 68% of the volatiles components present in the initial sample. Therefore, compared with evaporation, our results suggest that FC is a potential alternative as non-thermal technology to preserve diverse and interesting components from fresh juice.
KW - Antioxidant activity
KW - Aromatic profile
KW - Bioactive compounds
KW - Evaporation
KW - Freeze crystallization
KW - Pomegranate juice
UR - http://www.scopus.com/inward/record.url?scp=85105090124&partnerID=8YFLogxK
U2 - 10.1016/j.fbio.2021.101106
DO - 10.1016/j.fbio.2021.101106
M3 - Article
AN - SCOPUS:85105090124
SN - 2212-4292
VL - 41
JO - Food Bioscience
JF - Food Bioscience
M1 - 101106
ER -