Foods
·
2019
·Vol. 8
·期 8
·286
·
IF 3.011
Bin Jiang,Jiaxin Na,Lele Wang,Dongmei Li,Chunhong Liu,Zhibiao Feng
For the purpose of reducing pollution and the reutilization of salted egg whites, which are byproducts of the manufacturing process of salted egg yolks and normally treated as waste, an aqueous two-phase flotation (ATPF) composed of polyethylene glycols (PEG 1000) and (NH4)2SO4was applied to develop a simple, inexpensive and efficient process for the separation of ovalbumin (OVA) from salted egg whites. The effects of the concentration of PEG, the concentration of (NH4)2SO4, the flow rate and the flotation time on the flotation efficiency (Y) and purity (P) of OVA were investigated. A response surface method (RSM) experiment was carried out on the basis of a single-factor experiment. An efficient separation was achieved using ATPF containing 5 mL of 80% PEG 1000 (w/w), 28 mL of 28% (NH4)2SO4(w/w), 35 mL/min of the flow rate and 30 min of the flotation time, while 2 mL of the salted egg white solution (salted eggs white (v): water (v) = 1:4) was loaded. Under the optimal conditions,YandPof OVA could reach 82.15 ± 0.24% and 92.98 ± 0.68%, respectively. The purified OVA was characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), reverse phase high-performance liquid chromatography (RP-HPLC), liquid chromatography-nano electrospray ionisation mass spectrometry (Nano LC-ESI-MS/MS), ultraviolet spectrum (UV), fluorescence spectrum (FL) and fourier transform infrared spectroscopy (FT-IR). The results indicated that the purity of OVA obtained by ATPF was satisfactory and there was no obvious difference in the structure of the OVA separated by ATPF and the standard. The results of the functional properties revealed no significant differences between OVA obtained by ATPF and the standard in oil binding capacity, viscosity, emulsibility and foam capacity.Keywords:reutilization of food waste;salted egg white;ovalbumin;extraction;aqueous two-phase flotation
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD HYDROCOLLOIDS
·
2023
·
IF 10.7
Hui Xue,Tianfeng Han,Guowen Zhang,Xiaobo Hu,Ruiling Li,Huilan Liu,Rui Li,Yonggang Tu,Yan Zhao
Salted preserved eggs are made using poultry eggs under the combined action of NaOH, NaCl, and heat. To elucidate the main basis and mechanism of the formation of salted preserved egg white, the effects of NaOH (0.5–2.5%), NaCl (0–1.2%), and heat (72–100 °C) on the properties of ovalbumin (the most abundant protein in poultry egg whites) gel were studied. With increasing NaOH addition, the pH and the absolute value of zeta potential (TAV-ZP) increased, the opacity and Hunter whiteness decreased, and the relaxation time (T 2 ) initially decreased and then increased. With increasing NaCl addition and heating temperature, the pH and TAV-ZP decreased, the opacity and Hunter whiteness increased, and T 2 decreased first and then increased. In addition, the hardness and cohesiveness of the ovalbumin gel were greatly modified by NaOH, NaCl, and heat. NaOH contributed to the formation of the gel network structure. In addition, the surface hydrophobicity (H 0 ) analysis result indicated that the tertiary structure of the ovalbumin had changed during the formation of the ovalbumin gel. The correlation analysis results showed that electrostatic repulsion played a vital role in the formation of the transparent ovalbumin gel, and the transparent ovalbumin gel possessed the following characteristics: low aggregation degree, high cross-linking degree, high immobilized water content, gel network structure, and the fully unfolded structure of ovalbumin molecules. In general, the ovalbumin formed a unique gel under the combined action of NaOH, NaCl, and heat. This study could provide theoretical guidance for the processing and control of salted preserved eggs and a reference for highly transparent egg white gel products.
研究领域:
食品科学
·
蛋白质化学
·
凝胶形成
✓ 已验证
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2023
·
IF 6
Lixin Tan,Mengting Zheng,Shuping Chen,Na Wu,Lilan Xu,Yan Zhao,Yao Yao,Yonggang Tu
In order to clarify the quality formation process of low-NaCl salted eggs (LSEs) under the dual action of vacuum and salt, changes of physicochemical properties, molecular structure, and microstructures of egg white as well as interior and exterior yolks were systematically studied. Results showed that the salt content of egg whites and egg yolks increased to around 5% and 1% respectively, which were only about half of their traditional counterparts. Exterior yolk exudes more oil than the interior yolk, which was consistent with the observation of a more compact microstructure by scanning electron microscopy (SEM). Rheological testing demonstrated a significant increase in the viscosity of yolks but a decrease of egg whites. At the molecular level, proteins of egg white and yolk had gone through the process of denaturation and aggregation, but their change tendencies of free sulfhydryl group, surface hydrophobicity and secondary structure were slightly different. In summary, vacuum assisted two-stage pickling could effectively shorten the ripening time of salted eggs and reduce salt content without compromising their good quality.
研究领域:
食品科学
·
化学
·
微生物学
·
生物物理学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）