Preparation of Antarctic Krill Oil Emulsion and Its Stability under Catalase Treatment

Making Antarctic krill oil into emulsion is a good way to utilize Antarctic krill, but proliferation of microorganisms cannot be ignored. H 2 O 2 is widely used in the sterilization of liquid food since its decomposition products are environmentally friendly, although residual H 2 O 2 should be remo...

Full description

Bibliographic Details
Published in:Foods
Main Authors: Zhenxiao Zheng, Kai Zhu, Zhiyuan Dai
Format: Article in Journal/Newspaper
Language:English
Published: MDPI AG 2021
Subjects:
Online Access:https://doi.org/10.3390/foods10112797
https://doaj.org/article/ccced9a5f82143f5b6104a8614d4221d
Description
Summary:Making Antarctic krill oil into emulsion is a good way to utilize Antarctic krill, but proliferation of microorganisms cannot be ignored. H 2 O 2 is widely used in the sterilization of liquid food since its decomposition products are environmentally friendly, although residual H 2 O 2 should be removed for food safety. Adding catalase (CAT) is an effective means to do this. However, the enzyme activity center of CAT is the iron porphyrin group, which has the risk of accelerating lipid oxidation in the oil emulsion. Therefore, we hypothesized that CAT might not be suitable for the removal of H 2 O 2 in Antarctic krill oil emulsion. In this paper, Antarctic krill oil emulsion was prepared, and then the effect of CAT on the emulsion was studied through visual observation, microscopic morphology observation, turbidity and stability, particle size, and ΞΆ-potential; finally, the mechanism of CAT destroying the emulsion was explored from the perspective of lipid oxidation. The results showed that a stable Antarctic krill emulsion was prepared using Tween-80 as the emulsifier, with the oil concentration of 1% ( v / v ) and the ratio of surfactant to oil phase of 1:5 ( v/v ). The emulsion treated with CAT had undergone demulsification, stratification, and coagulation after 2 days of incubation, while the emulsion treated with superoxide dismutase (SOD) and bovine serum albumin (BSA) changed little. In addition, the thiobarbituric acid reactive substances (TBARS) value and the content of hydroxyl radicals in the CAT group increased significantly. The preliminary research results indicated that the effect of CAT on the emulsion related to the lipid oxidation caused by the iron porphyrin group at the center of the enzyme activity. All these results indicated that CAT was not suitable for the removal of residual H 2 O 2 in Antarctic krill oil emulsion. Moreover, it is helpful to avoid the contact of Antarctic krill oil emulsion and CAT during the processing of the krill.