5. Applications of MAE as a green extraction technique in food industry

MAE is usually used in environmental analyses. Extraction of polyaromatic hydrocarbons, polychlorobiphenyls, and organochlorine pesticides from matrices such as sediment and soil has been studied. MAE has also been applied to food analyses. Extraction of 16 organochlorine insecticides in sesame seeds, use of microwave confinement in drug extraction from seed, and extraction and testing of lidocaine, methadone, diazepam, nordiazepam, proxifene, and norproxifen materials as model medicines are the main applications in which the MAE technique is used. At the same time, extraction of natural products such as drugs (pentobarbital, ketamine, diazepam); extraction from skeletal tissues; extraction of natural products such as terpenes, alkaloids, volatile oils, and carotenoids; extraction of color pigments in the paprika; identification of pesticide residues in sunflower seeds; discovery of a rapid method using dichloromethane solvent; and applications such as rapid extraction of aromatic hydrocarbons are examples of other applications that can be given for MAE technique. The irradiation power, time, number of revolutions, and solvent volume among the MAE method parameters can be optimized using experimental design methodology [20]. Examples of food industry that can be given to microwave-assisted extractions are very diverse and are summarized in general as the following, diversified by explaining the study title and scope:

g. Microwave-assisted extraction of flavonoids: This study investigated the MAE mechanism

Microwave-Assisted Green Extraction Technology for Sustainable Food Processing

http://dx.doi.org/10.5772/intechopen.76140

h. Microwave-assisted extraction of anthocyanin from Chinese bayberry and its effects on anthocyanin stability: The study used MAE to extract antioxidant compounds from Chinese bayberry at 80C for 15 min. The results for anthocyanin content and antioxidant

i. Microwave-assisted extraction of pectin from jackfruit rinds using different power levels: Since conventional extraction of pectin is time-consuming (1 h), this study focused on the use of MAE to recover pectin from fruit material (10 min). The experiments were done at 90C for conventional method, and three different power levels of 450, 600, and 800 W

j. Optimization of microwave-assisted extraction of ergosterol from Agaricus bisporus L. byproducts using response surface methodology: The study compared MAE with conventional methods for time and solvent consumption. MAE was efficient where conventional methods were inappropriate. Ergosterol component was best extracted at around

19.42.9 min and at around 132.812.4 C yielding 556.126.2 mg of extract [30].

method [31].

50% power rate [32].

6. Advantages and disadvantages of MAE

k. Microwave-assisted extraction of phenolic compounds from olive leaves—a comparison wıth maceration: The purpose of the study was to extract phenolic compounds from olive leaves of with MAE methods using different solvents. Among the solvents used, ethanol was the most efficient where acetone was the least. The highest extraction yield was obtained at 24 h with conventional method, while it was obtained at 15 min with MAE

l. Extraction of phenolic compounds from melissa using microwave and ultrasound: The comparison of microwave and ultrasound has been studied for the extraction of essential oils from melissa. Extraction time and solid-to-solvent ratio were investigated for recovery of total phenolic compounds (TPC). Recovery rate for TPC was 145.8 mg extract/dry matter using MAE in 80% power rate where the yield was 105.5 mg extract/dry matter in

MAE process efficiency is dependent on various extraction parameters. These parameters can be counted as the nature of raw material, strength and level of microwave irradiation, extraction time, extraction pressure, and solvent flow rate. In the extraction process where the heatlabile compounds have to be recovered, lower levels of irradiation may bring lower efficiency because sensitive component recovery effectiveness may be decreased due to high microwave power levels. Extraction time is also important that is acts together with the microwave power. Even if the same amount of microwave power is used, if a raw material is extruded for a longer period, the yield will definitely be lower. Because the liminal structure of the material will

, respectively.

173

activity were obtained as 2.95 0.08 mg<sup>g</sup><sup>1</sup> and as 279.96 0.1 <sup>μ</sup>mol g<sup>1</sup>

So, MAE showed an important potential to recover bioactive compounds [28].

were used for MAE. The highest efficiency was obtained at 450 W power [29].

and exerts the key points that bring advantage in extraction [27].


g. Microwave-assisted extraction of flavonoids: This study investigated the MAE mechanism and exerts the key points that bring advantage in extraction [27].

dichloromethane solvent; and applications such as rapid extraction of aromatic hydrocarbons are examples of other applications that can be given for MAE technique. The irradiation power, time, number of revolutions, and solvent volume among the MAE method parameters can be optimized using experimental design methodology [20]. Examples of food industry that can be given to microwave-assisted extractions are very diverse and are summarized in

a. Supercritical carbon dioxide and microwave-assisted extraction of functional lipophilic compounds from Arthrospira platensis: The study investigated the effect of extraction parameters on lipophilic material content in the extracts obtained by using SFE and MAE methods. Pressure and temperature in the study were 45 MPa and 60C, respectively. When the cosolvent is used at 53.33% of CO2 ratio, the highest amount of extracts was obtained. In case of MAE extraction, the most efficient experimental condition was

b. Green extraction from pomegranate marcs for the production of functional foods and cosmetics: The aim of the study was to investigate the potential of retrieving polyphenolic antioxidants by green extractions directly from wet pomegranate juice marcs, the fresh edible by-products obtained after pomegranate juice processing. Green extraction was performed below 50C, microwave-assisted extraction (MAE) was done below 300 W, and ultrasound-assisted extraction (UAE) was operated with the output of 200 W. Each

c. Applications of green extraction of phytochemicals from fruit and vegetables: This study compared the conventional methods for extraction with the new methods that are called green extraction techniques and for recovery of phytochemicals and natural compounds (phenolic compounds, ascorbic acid, carotenoids, aroma compounds, etc.) obtained from

d. Novel eco-friendly techniques for extraction of food-based lipophilic compounds from biological materials: This study investigated the various possible novel eco-friendly extraction methods, their scientific concepts, principles, challenges, limitations, and tech-

nological effort needed for successful implementation at the production scale [24].

e. Phenolic compound recovery from grape fruit and by-products: Several convectional and emerging technologies (including MAE) have been evaluated in order to recover phenolic compounds from grape fruits and wastes such as chemical, physical, and biotechnological techniques, which offer different advantages related to economic, environmental, time-

f. Microwave-assisted extraction of free amino acids from foods: In this study the use of microwave energy to assist extraction of amino acids from foods is presented. This method is compared with shaking extraction, and the effects of various experimental conditions on the extraction yield are tested (irradiation time, temperature, extractant volume, mixing, etc.) in order to determine the optimum extraction conditions. The efficiency of extraction gave better results for MAE by 10%, and the extraction time was

general as the following, diversified by explaining the study title and scope:

172 Emerging Microwave Technologies in Industrial, Agricultural, Medical and Food Processing

technique has been efficient in obtaining different foodstuffs [22].

obtained at 400 W and 50C [21].

plant materials [23].

saving, and yield aspects [25].

reduced by 66% [26].

