Agrofood Waste and By-Product Valorization, Extraction, and Characterization of Pectin from the Waste Biomass Fruit Peel of Aframomum angustifolium Using Response Surface Methodology as Alternative Sources of a Functional Pectin

Table 3

Physical, chemical, physicochemical, and functional properties of pectin extracted from A. angustifolium.

Characteristics	Properties		Microwave extraction	Acid extraction
Physical	Yield (%)		4.74 ± 0.10^a	3.09 ± 0.03^b
	Color		Light brown	Light brown
Chemical	Moisture (%)		6.5 ± 0.14^a	6.9 ± 0.42^a
	Mineral ion (mg/kg)	Ca	5440 ± 1.41^a	5440.5 ± 0.71^a
		Mg	3303.55 ± 0.35a	3304.65 ± 0.21^a
		K	6741.66 ± 0.07^a	6740.76 ± 0.06^a
		Na	131.01 ± 0.65^a	131.46 ± 0.02^a
	Alkalinity		2.55 ± 0.07^a	2.45 ± 0.07^a
	Ash (%)		1.56 ± 0.34^a	1.56 ± 0.54^a
	Equivalent weight (mg/ml)		852.49 ± 16.59^b	882.1 ± 9.04^a
	Methoxyl content (%)		33.06 ± 1.65^a	31.85 ± 0.36^a
Physicochemical	Solubility in hot water		Soluble	Soluble
	Solubility in cold water		Partly dissolves after vigorous shaking	Partly dissolves after vigorous shaking
	Pectin suspension soluble in cold alkali (0.1 N NaOH)		Pectin suspension forms yellow precipitate	Pectin suspension forms yellow precipitate
	Pectin suspension soluble in hot alkali (0.1 N NaOH)		Pectin suspension dissolves and turns milky	Pectin suspension dissolves and turns milky
Functional	Degree of esterification (% DegE)		67.96 ± 1.18	66.61 ± 0.46

Scores with different letters on superscripts (a and b) are significantly different at  < 0.05.