scholarly journals Characterization and Demulsification of the Oil-Rich Emulsion from the Aqueous Extraction Process of Almond Flour

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1228
Author(s):  
Fernanda F. G. Dias ◽  
Neiva M. de Almeida ◽  
Thaiza S. P. de Souza ◽  
Ameer Y. Taha ◽  
Juliana M. L. N. de Moura Bell

The aqueous extraction process (AEP) allows the concurrent extraction of oil and protein from almond flour without the use of harsh solvents. However, the majority of the oil extracted in the AEP is present in an emulsion that needs to be demulsified for subsequent industrial utilization. The effects of scaling-up the AEP of almond flour from 0.7 to 7 L and the efficiency of enzymatic and chemical approaches to demulsify the cream were evaluated. The AEP was carried out at pH 9.0, solids-to-liquid ratio of 1:10, and constant stirring of 120 rpm at 50 °C. Oil extraction yields of 61.9% and protein extraction yields of 66.6% were achieved. At optimum conditions, enzymatic and chemical demulsification strategies led to a sevenfold increase (from 8 to 66%) in the oil recovery compared with the control. However, enzymatic demulsification resulted in significant changes in the physicochemical properties of the cream protein and faster demulsification (29% reduction in the incubation time and a small reduction in the demulsification temperature from 55 to 50 °C) compared with the chemical approach. Reduced cream stability after enzymatic demulsification could be attributed to the hydrolysis of the amandin α-unit and reduced protein hydrophobicity. Moreover, the fatty acid composition of the AEP oil obtained from both demulsification strategies was similar to the hexane extracted oil.

2017 ◽  
Vol 2017 ◽  
pp. 1-5
Author(s):  
Yong-Dong Xu ◽  
Yan-Ping Zhou ◽  
Jing Chen

Sesame oil produced by the traditional aqueous extraction process (TAEP) has been recognized by its pleasant flavor and high nutrition value. This paper developed a rapid and nondestructive method to predict the sesame oil yield by TAEP using near-infrared (NIR) spectroscopy. A collection of 145 sesame seed samples was measured by NIR spectroscopy and the relationship between the TAEP oil yield and the spectra was modeled by least-squares support vector machine (LS-SVM). Smoothing, taking second derivatives (D2), and standard normal variate (SNV) transformation were performed to remove the unwanted variations in the raw spectra. The results indicated that D2-LS-SVM (4000–9000 cm−1) obtained the most accurate calibration model with root mean square error of prediction (RMSEP) of 1.15 (%, w/w). Moreover, the RMSEP was not significantly influenced by different initial values of LS-SVM parameters. The calibration model could be helpful to search for sesame seeds with higher TAEP oil yields.


2013 ◽  
Vol 781-784 ◽  
pp. 1886-1890
Author(s):  
Fei Long Sun ◽  
Zhang Peng Li ◽  
Ting Li ◽  
Yong Fan ◽  
Yan Chu ◽  
...  

Natural pigments have raised a growing interest due to their extensive range of colors, innocuous and beneficial health effects. In this paper, the extraction process and stability of strawberry red pigment were studied. An orthogonal test [L16(4)4] was applied to get the best extraction conditions. Results showed that the optimum conditions were that the extraction temperature was 65C, the solid-liquid ratio was 1:5 (g/mL), the ratio of 1.5mol/L hydrochloride to 97.5% ethanol was 3:17 (mL/mL), and the extraction time was 4.5 hours. The effects of heat treatment, oxidant, sugar and preservatives on the stability of strawberry red pigment were also discussed. The stability of strawberry red pigment was found to be affected by high temperature, hydrogen peroxide, and potassium sorbate. This study is expected to provide a basis for further research, development, and utilization of strawberry red pigment.


Processes ◽  
2019 ◽  
Vol 7 (11) ◽  
pp. 844 ◽  
Author(s):  
Neiva M. de Almeida ◽  
Fernanda F. G. Dias ◽  
Maria I. Rodrigues ◽  
Juliana M. L. N. de Moura Bell

The enzyme-assisted aqueous extraction process (EAEP) is an environmentally friendly strategy that simultaneously extracts oil and protein from several food matrices. The aim of this study was to investigate the effects of pH (6.5–9.5), temperature (45–55 °C), solids-to-liquid ratio (SLR) (1:12–1:8), and amount of enzyme (0.5–1.0%) on the extraction and separation of oil and protein from almond flour using a fractional factorial design. Oil and protein extraction yields from 61 to 75% and 64 to 79% were achieved, respectively. Experimental conditions resulting in higher extractability were subsequently replicated for validation of the observed effects. Oil and protein extraction yields of 75 and 72% were achieved under optimized extraction conditions (pH 9.0, 50 °C, 1:10 SLR, 0.5% (w/w) of enzyme, 60 min). Although the use of enzyme during the extraction did not lead to significant increase in extraction yields, it did impact the extracted protein functionality. The use of enzyme and alkaline pH (9.0) during the extraction resulted in the production of more soluble peptides at low pH (5.0), highlighting possible uses of the EAEP skim protein in food applications involving acidic pH. The implications of the use of enzyme during the extraction regarding the de-emulsification of the EAEP cream warrant further investigation.


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