Ethanol concentration of fermented broth by ohmic-assisted hydrodistillation

Abstract

Ohmic-assisted hydrodistillation (OAHD) as an innovative extraction method was employed to concentrate ethanol from corn beer. OAHD reduces the time and energy required for distillation of bioethanol production compared to traditional method. OAHD process was compared to traditional hydrodistillation (HD) for three liters of 13% (v/v) beer at a constant wattage of 168 W. Test results indicate that the required energy for separation of ethanol in OAHD is 77% less than HD. Moreover, OAHD completed the distillation process in 70.6±1.8 min while HD required 116.1±7.8 min. The concentrations of ethanol in the final distilled product from both methods were similar (56.5%± 1.3 for OAHD vs. 52.3%± 4.0 for HD). Interestingly, the process control in OAHD is faster and distillation can be stopped quickly, and consequently, it will contain less unwanted distillate in comparison with HD. The findings of this study introduce OAHD as a potentially economical and environmentally friendly method for bioethanol distillation process.

Food texture as affected by ohmic heating: Mechanisms involved, recent findings, benefits, and limitations

“…In addition, this innovative technique can minimize the textural damages of fragile vegetables during thermal sterilization (Eliot-Godéreaux, Zuber & Goullieux, 2001). Better process control () also enables the food processor to control and define the product texture precisely and stop the thermal process whenever necessary (Gavahian, Farahnaky, Shavezipur, & Sastry, 2016;Wang, Li, Tatsumi, Liu, Chen & Li, 2007). Some studies also claimed that ohmic heating can result in a product with better textural properties than the traditional heating procedures (Piette et al, 2004).…”

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

“…Different frequencies can also be applied to the food material in an ohmic heating process but the higher frequencies (>100 Hz) are usually preferred as the low‐frequencies (˂60 Hz) increase the rate of electrode corrosion and electrolysis reactions (Gavahian & Farahnaky, ; Ramaswamy, Marcotte, Sastry, & Abdelrahim, ). While controlled low temperature MEF has been mainly used as a technique to enhance cell permeability (Kulshrestha & Sastry, ; Sensoy & Sastry, ; Wang & Sastry, ), ohmic heating has a wider range of applications, including microbial inactivation (Kim, Ryang, Lee, Kim, & Rhee, ; Ryang et al., ; Somavat, Mohamed, Chung, Yousef, & Sastry, ), cooking (Farahnaky, Azizi, & Gavahian, ; Jittanit et al., ), and distillation (Gavahian, Farahnaky, & Sastry, , b; Gavahian, Farahnaky, Shavezipur, & Sastry, ). The benefits of controlled low temperature MEF and ohmic heating, such as saving in energy and time, has been highlighted in the literature (Gavahian et al., ; Ramaswamy et al., ).…”

“…This results in incomplete extraction from the insufficiently heated portion of feed material, the release of undesirable compounds from overheated parts, thermal degradation of the released compounds, along with the formation of a sediment layer at the bottom of the extraction chamber. The latter acts as a thermal barrier and reduces the heat transfer rate and energy efficiency of the extraction system (Gavahian et al., ). On the other hand, ohmic heating follows a different mechanism, that is, energy conversion from electric to thermal, and it generates heat within the materials.…”

Characterization of Natural Antimicrobials in Food System

“…Moreover, process parameters such as, process temperature and time, are difficult to control which may result in incomplete or prolonger extraction. So, researchers are looking for alternatives to this tedious extraction technique [32] [33] [34].…”