اثر گرادیان ولتاژ و نوع الکترود بر خواص کیفی آب هویج در حرارت‌دهی اهمیک

حرارت‌دهی اهمیک که به عنوان حرارت‌دهی ژول نیز شناخته می‌شود، یکی از روش‌های حرارت‌دهی محصولات غذایی است. گرمایش اهمیک یک فرآیند حرارتی‌دهی پیشرفته است که در آن ماده غذایی بعنوان مقاومت الکتریکی عمل می‌کند. سامانه آزمایشگاهی آن معمولا شامل الکترودهایی است که با مواد غذایی تماس داشته و به موجب آن الکتریسیته از طریق ماده غذایی و با استفاده از تغییر ولتاژ منتقل می‌گردد. در این تحقیق از یک سیستم گرمایش اهمیک برای تغلیظ آب هویج استفاده شد و اثر گرمایش اهمیک بر تغییر کلی رنگ (eδ)، درصد تغییر ph و میزان مصرف انرژی ویژه آب هویج در گرادیان‌های مختلف ولتاژ (15، 20 و 25 ولت بر سانتی‌متر) با استفاده از الکترودهای مختلف (استیل، مس، آلومینیوم و روی) بررسی شد. نتایج نشان داد که با افزایش گرادیان ولتاژ، انرژی مصرفی ویژه کاهش یافت. الکترود مس بهترین عملکرد را از نظر درصد تغییر ph، مصرف انرژی ویژه و تغییر کلی رنگ (eδ) داشت. انرژی مصرفی ویژه از 3.45 تا 3.87 مگا ژول بر کیلوگرم به ترتیب برای الکترود مس در گرادیان ولتاژ 25 ولت بر سانتی‌متر و الکترود استیل در گرادیان ولتاژ 15 ولت بر سانتی‌متر تغییر یافت. حرارت‌دهی اهمیک که به عنوان حرارت‌دهی ژول نیز شناخته می‌شود، یکی از روش‌های حرارت‌دهی محصولات غذایی است. گرمایش اهمیک یک فرآیند حرارتی‌دهی پیشرفته است که در آن ماده غذایی بعنوان مقاومت الکتریکی عمل می‌کند. سامانه آزمایشگاهی آن معمولا شامل الکترودهایی است که با مواد غذایی تماس داشته و به موجب آن الکتریسیته از طریق ماده غذایی و با استفاده از تغییر ولتاژ منتقل می‌گردد. در این تحقیق از یک سیستم گرمایش اهمیک برای تغلیظ آب هویج استفاده شد و اثر گرمایش اهمیک بر تغییر کلی رنگ (eδ)، درصد تغییر ph و میزان مصرف انرژی ویژه آب هویج در گرادیان‌های مختلف ولتاژ (15، 20 و 25 ولت بر سانتی‌متر) با استفاده از الکترودهای مختلف (استیل، مس، آلومینیوم و روی) بررسی شد. نتایج نشان داد که با افزایش گرادیان ولتاژ، انرژی مصرفی ویژه کاهش یافت. الکترود مس بهترین عملکرد را از نظر درصد تغییر ph، مصرف انرژی ویژه و تغییر کلی رنگ (eδ) داشت. انرژی مصرفی ویژه از 3.45 تا 3.87 مگا ژول بر کیلوگرم به ترتیب برای الکترود مس در گرادیان ولتاژ 25 ولت بر سانتی‌متر و الکترود استیل در گرادیان ولتاژ 15 ولت بر سانتی‌متر تغییر یافت.

Effect of Voltage Gradient and Electrode Type on Qualitative Properties of Carrot Juice in Ohmic Heating

Ohmic heating, also known as Joule heating, is an electric heating method for food products. Ohmic heating is an advanced heating process in which foods act as electrical resistances. Its laboratory system usually involves electrodes that are in contact with food, whereby electricity is transmitted through the foodstuff by a voltage change. In this research, the effect of ohmic heating on the specific energy consumption, total color change (ΔE) and percentage of pH change of carrot juice in different voltage gradients (15, 20 and 25V/cm) using different electrodes (steel, copper, aluminum and zinc) were investigated. The results showed that with increasing the voltage gradient, the special energy consumption decreased. The copper electrode has the best performance in percentage of pH change, specific energy consumption and total color change (ΔE). The specific energy consumption was changed from 3.45 to 3.87 MJ/kg for the copper electrode on gradient of 25V/cm and the steel electrode on voltage gradient of 15V/cm, respectively. Ohmic heating, also known as Joule heating, is an electric heating method for food products. Ohmic heating is an advanced heating process in which foods act as electrical resistances. Its laboratory system usually involves electrodes that are in contact with food, whereby electricity is transmitted through the foodstuff by a voltage change. In this research, the effect of ohmic heating on the specific energy consumption, total color change (ΔE) and percentage of pH change of carrot juice in different voltage gradients (15, 20 and 25V/cm) using different electrodes (steel, copper, aluminum and zinc) were investigated. The results showed that with increasing the voltage gradient, the special energy consumption decreased. The copper electrode has the best performance in percentage of pH change, specific energy consumption and total color change (ΔE). The specific energy consumption was changed from 3.45 to 3.87 MJ/kg for the copper electrode on gradient of 25V/cm and the steel electrode on voltage gradient of 15V/cm, respectively. Ohmic heating, also known as Joule heating, is an electric heating method for food products. Ohmic heating is an advanced heating process in which foods act as electrical resistances. Its laboratory system usually involves electrodes that are in contact with food, whereby electricity is transmitted through the foodstuff by a voltage change. In this research, the effect of ohmic heating on the specific energy consumption, total color change (ΔE) and percentage of pH change of carrot juice in different voltage gradients (15, 20 and 25V/cm) using different electrodes (steel, copper, aluminum and zinc) were investigated. The results showed that with increasing the voltage gradient, the special energy consumption decreased. The copper electrode has the best performance in percentage of pH change, specific energy consumption and total color change (ΔE). The specific energy consumption was changed from 3.45 to 3.87 MJ/kg for the copper electrode on gradient of 25V/cm and the steel electrode on voltage gradient of 15V/cm, respectively. Ohmic heating, also known as Joule heating, is an electric heating method for food products. Ohmic heating is an advanced heating process in which foods act as electrical resistances. Its laboratory system usually involves electrodes that are in contact with food, whereby electricity is transmitted through the foodstuff by a voltage change. In this research, the effect of ohmic heating on the specific energy consumption, total color change (ΔE) and percentage of pH change of carrot juice in different voltage gradients (15, 20 and 25V/cm) using different electrodes (steel, copper, aluminum and zinc) were investigated. The results showed that with increasing the voltage gradient, the special energy consumption decreased. The copper electrode has the best performance in percentage of pH change, specific energy consumption and total color change (ΔE). The specific energy consumption was changed from 3.45 to 3.87 MJ/kg for the copper electrode on gradient of 25V/cm and the steel electrode on voltage gradient of 15V/cm, respectively. Ohmic heating, also known as Joule heating, is an electric heating method for food products. Ohmic heating is an advanced heating process in which foods act as electrical resistances. Its laboratory system usually involves electrodes that are in contact with food, whereby electricity is transmitted through the foodstuff by a voltage change. In this research, the effect of ohmic heating on the specific energy consumption, total color change (ΔE) and percentage of pH change of carrot juice in different voltage gradients (15, 20 and 25V/cm) using different electrodes (steel, copper, aluminum and zinc) were investigated. The results showed that with increasing the voltage gradient, the special energy consumption decreased. The copper electrode has the best performance in percentage of pH change, specific energy consumption and total color change (ΔE). The specific energy consumption was changed from 3.45 to 3.87 MJ/kg for the copper electrode on gradient of 25V/cm and the steel electrode on voltage gradient of 15V/cm, respectively. Ohmic heating, also known as Joule heating, is an electric heating method for food products. Ohmic heating is an advanced heating process in which foods act as electrical resistances. Its laboratory system usually involves electrodes that are in contact with food, whereby electricity is transmitted through the foodstuff by a voltage change. In this research, the effect of ohmic heating on the specific energy consumption, total color change (ΔE) and percentage of pH change of carrot juice in different voltage gradients (15, 20 and 25V/cm) using different electrodes (steel, copper, aluminum and zinc) were investigated. The results showed that with increasing the voltage gradient, the special energy consumption decreased. The copper electrode has the best performance in percentage of pH change, specific energy consumption and total color change (ΔE). The specific energy consumption was changed from 3.45 to 3.87 MJ/kg for the copper electrode on gradient of 25V/cm and the steel electrode on voltage gradient of 15V/cm, respectively.