Extraction of Phospholipids from Egg Yolk Flakes Using Aqueous Alcohols

Abstract

Two alcohols, ethanol and butanol, with different water contents were evaluated for phospholipids (PL) sequential extraction from drum dried egg yolk flakes. It showed that butanol was more effective in extracting total yolk lipids compared to ethanol, but the PL in the extract had the same concentration as in the original yolk total lipid. The use of aqueous ethanol of 95 and 75% resulted in lipid extracts with higher PL concentration during the initial stages of the sequential extraction. When ethanol was further diluted to a concentration of 55%, the solvent lost its PL extraction ability, and the total lipid recovery also decreased dramatically. When both the PL purity and recovery were considered, 75% ethanol was the most effective aqueous alcohol for PL extraction and enrichment from the yolk flakes. In the first stage of extraction using such a solvent, 67% of the total PL in the original yolk was recovered in a lipid fraction with a PL purity of 75%. This study identified the optimal ethanol concentration for PL extraction from dried egg yolk. With this information, the best solid:solvent ratio can be designed to extract and enrich the polar lipids from lipid‐bearing materials with known moisture content using a renewable or “green” solvent, ethanol.

Interactions between egg storage duration and broiler breeder age on egg fat content, chicken organ weights, and growth performance

“…The yolk fat percentage was lower after 12 and 19 D than after 5 D of egg storage. This is consistent with Wang et al. (2017a) , who noted a decrease in total yolk fat after 10 D of storage at a storage temperature of 22°C (Δ = −1.42 g/100 g dry egg yolk) and after 20 D of storage at a storage temperature of 4°C (Δ = −3.14 g/100 g dry egg yolk).…”

“…During egg storage, yolk lipid components (especially phospholipids) can be hydrolyzed by endogenous enzymes, resulting in free fatty acids, which are the main substrates of lipid peroxidation. Lipid peroxidation can generate hydroperoxides and secondary oxidation products, finally decreasing the yolk lipid content ( Wang et al., 2017a ). Whether the decrease in yolk fat content or the change in yolk lipid composition might have consequences for embryonic development and hatchling quality will be discussed below.…”

Extraction of phospholipids from a dairy by-product (whey protein phospholipid concentrate) using ethanol

“…The extraction procedure, which has similar extraction principles as the STEP method (Wang et al, 2016(Wang et al, , 2017, was performed using WPPC as a feedstock. A laboratory extraction system ( Figure 1) designed for the STEP method on egg yolk was adapted to extract total lipid and PL from WPPC.…”

Impact of Hydro-Alcoholic Solvents on the Oil and Phenolics Extraction from Walnut (Juglans regia L.) Press-Cake and the Self-Emulsification of Extracts

“…Another class of surface-active molecules is lecithin, which is a mixture provided with diverse contents and types of phospholipids. Phospholipids can be recovered by water–ethanol mixtures at a yield that increases significantly with the ethanol content [ 45 , 46 ]. Generally speaking, emulsifying properties of extracts obtained by hydrated mixtures or non-aqueous solvents are rarely addressed in literature.…”