Conventional Extraction of Betalain Compounds From Beetroot Peels With Aqueous Ethanol Solvent

Abstract

Consumer concern over artificial food additives has stimulated production of pigments from natural sources. The aim of this study was to examine the effects of process variables on the content of colour compounds (betaxanthin and betacyanin) in beetroot peel juice extracted by conventional method. In this research, the extraction processes were carried out according to the central composite design with different process variables. Quantitative measurements of the basic colour compounds in beetroot extract were performed using spectrophotometer. From our experiment, it was found that the most adequate extraction conditions, which gave the highest yield of colour compounds (952.5 mg l–1 of betaxanthin and 1361 mg l–1 of betacyanin), were extraction time 1 h, operating temperature 20 ºC, and solvent ratio 0.8 w/v. Being a conventional heating method, it is a simple and cost efficient process with relatively high yield.

Optimisation of the ultrasound-assisted extraction of betalains and polyphenols from Amaranthus hypochondriacus var. Nutrisol

“…Li et al [9] determined the betalain content in three amaranth species and in different parts of the plant, obtaining the maximum content of 20.93 mg/100 g d.m in Amaranthus caudatus leaves in an extraction time of 15 h. Das et al [13] reported a maximum content of 159.09 mg/100 g d.m in 60 min from foliage of Amaranthus cruentus . However, Maran et al [14] reported a maximum content of total betalains of 41.54 mg/100 g d.m in an extraction time of 115 min in Opuntia ficus-indica fruit, whereas Zin et al [15] obtained maximum concentrations of betacyanins and betaxanthins in 1 h in beetroot peels. Although these studies have been of great importance regarding the extraction and characterisation of betalains in different sources, it is noteworthy that high pigment concentration is achieved in long extraction times, which leads to higher energy consumption.…”

Characterization of Cylindra Beetroot Wastes Volarized With Green Solvent by Thermal Emerging Technology (Microwave Irradiation)

“…Nevertheless, care should be made for subsequent pigment compartmentalizations. The scavenged amounts of BX are about two or three times lower than BC which might be either due to their natural occurrence portion [30] or the processing conditions that have affected their degradation as well. Hence, the quantity of betaxanthin in the pressed juice and the extract was double as to betacyanin in the study of Slavov and co-workers [31].…”

Recovery of Phytochemicals via Electromagnetic Irradiation (Microwave-Assisted-Extraction): Betalain and Phenolic Compounds in Perspective

“…In the UV visible region, betaxanthin and betacyanin are detectable at the maximum wavelength absorption of 480 and 540 nm, respectively [27]. Betacyanin is responsible for the red color but also more tolerant to heat and stable to processing conditions than the yellow color giving betaxanthin [3,9,39].…”

“…Heating mode, duty cycle, power or heat energy, and temperature in an advanced microwave set up are basic operational parametric modes in MAE of betalains and phenolic compounds. Response surface methodology (RSM) is a suitable tool to approach the efficiency of MAE through the interaction of process variables despite the fact that the predicted values estimated by the model are only within the experimental limit [9,18,62,63,[67][68][69][70][71][72][73]. Central composite design was mostly chosen for the investigation of each or parallel effects of process variables on the corresponding response.…”

“…This led to them being grouped as betalains in 1968 [3]. Among the acknowledged sources of betalains, i.e., beetroot, swiss chard, dragon fruit, and prickly pear [3][4][5][6], beetroot has gained the most attention since, apart from the whole tuber, even their waste parts such as stalk [7], peel [8,9], and pomace [10,11] are rich in betalains. The ratio of color contents is decisively influenced by specie source, genetic, cultivar, or the environment of cultivation throughout growing, and the stages of harvesting [4,12,13].…”