The effect of temperature and moderate electric field pre‐treatment on carotenoid extraction from Heterochlorella luteoviridis

Abstract

Summary Moderate electric field (MEF) was evaluated as a pre‐treatment (0–180 V) to carotenoid extraction at four different temperatures (30, 40, 50 and 60 °C) followed by a extraction step using ethanol/water as solvent (75% of ethanol, v/v). During the extraction step, samples were collected at 1, 5, 30, 40 and 50 min. Results showed that MEF allowed higher carotenoid concentration at the beginning of the extraction step at 30, 40 and 50 °C, leading to better extraction results along the extraction time. A different behaviour was observed at 60 °C probably due to the thermal effects on the cell and to carotenoids thermal degradation. The highest extraction yield, 86% of the total carotenoid content (compared to exhaustive extraction), was achieved at both 40 and 50 °C with the MEF pre‐treatment, indicating that a high extraction yield can be obtained even at relatively low temperatures (40 °C).

Extraction from Food and Natural Products by Moderate Electric Field: Mechanisms, Benefits, and Potential Industrial Applications

“…Application of an electric field across food materials can increase the permeability due to inducing a trans‐membrane potential difference across the cell membrane. By applying an appropriate voltage across a cell (that is, the breakdown potential), cell permeability increases due to the localized electrical breakdown of the membrane (Ade‐Omowaye, Rastogi, Angersbach, & Knorret, ; Jaeschke, Merlo, Rech, Mercali, & Marczak, ; Sensoy & Sastry, ). The terms MEF and ohmic heating both refer to the process of subjecting a food material to an alternating current electric field.…”

“…Investigations on the applicability of MEF for extraction of food constituents, such as oils, hydrocolloids, and bioactive compounds, revealed the key benefits of this technique included enhanced yield (Aamir & Jittanit, ; Al‐Hilphy et al., ; Boonchoo et al., ; Coelho et al., ; Fraccola et al., ; Kulshrestha & Sastry, ; Kumari et al., ; Lakkakula et al., ; Lebovka et al., ; Loypimai et al., ; Nair et al., ; Pare et al., ; Pereira et al., ; Pootao & Kanjanapongkul, ; Saberian et al., ; Salengke et al., , ; Sensoy & Sastry, ; Tongprasan et al., ; Wang & Sastry, ), reduced process time (Al‐Hilphy et al., ; Jaeschke et al., ; Nair et al., ; Pereira et al., ; Pootao & Kanjanapongkul, ; Sakharam et al., ), enhanced product quality (Al‐Hilphy et al., ; Coelho et al., ; Lakkakula et al., ; Loypimai et al., ; Pootao & Kanjanapongkul, ; Salengke et al., ), and energy savings (Al‐Hilphy et al., ; Nair et al., ; Pereira et al., ; Pootao & Kanjanapongkul, ; Wang & Sastry, ) (Table ).…”

“…Extraction of economically valuable bioactive compounds from natural resources is an interesting topic for many researchers, and several studies have been conducted on this topic. Research has highlighted the benefits of the MEF technique for extraction of bioactive ingredients such as β‐carotene and lycopene (Aamir & Jittanit, ), chlorophyll and carotenoids (Fraccola et al., ; Jaeschke et al., ), phenolic compounds (Al‐Hilphy et al., ; Coelho et al., ), anthocyanin (Loypimai et al., ; Pereira et al., ), betanin (Kulshrestha & Sastry, ; Porras‐Parral et al., ), and herbal extract (Tongprasan et al., ).…”

“…Jaeschke et al. () extracted carotenoids from the microalga Heterochlorella luteoviridis following a MEF pretreatment at 30 °C in a 25% v/v ethanol solution. They found that the MEF pretreatment affected the extraction kinetics.…”

“…They found that the MEF pretreatment affected the extraction kinetics. According to the paper, MEF promoted cell membrane permeabilization and facilitated diffusion of carotenoids from microalgae cell to the solvent (Jaeschke et al., ).…”