Fruit By-Product Processing and Bioactive Compounds

Table 1

Means of total flavonoid content (TFC, mg/100 g), total phenolic content (TPC, mg/100 g), reducing power (FRAP <0.1 g/100 ml), and DPPH inhibition (IC50, %) of avocado peel, avocado seeds, kiwi fruit, orange peel, pineapple peel, and pomegranate skin during processing.

Fruit by-product	TRT	TFC (mg/100 g)^1	TPC (mg/100 g)	FRAP (0.1 mg/100 ml)	IC50 (%)
Avocado peel	Dried	136.9^a	1,017.2^b	93.6^d	14.5^c
	Blanched	63.1^b	359.1^d	169.0^a	11.1^d
	Frozen	20.6^c	1,000.5^c	128.3^c	55.6^b
	Fresh	14.4^d	2,466.8^a	149.2^b	76.6^a
Avocado seed	Dried	54.1^a	5,973.0^a	152.2^a	52.5^a
	Blanched	45.4^b	4,958.6^b	147.9^b	21.6^c
	Frozen	33.8^d	1,268.6^d	128.2^d	28.2^b
	Fresh	39.8^c	2,036.6^c	142.7^c	17.8^d
Kiwi fruit	Dried	10.6^a	4,571.9^a	59.9^b	32.1^b
	Blanched	1.3^b	852.6^b	93.6^a	43.2^a
	Frozen	0.0^c	324.2^c	32.1^c	30.0^c
	Fresh	1.3^b	331.8^c	28.5^d	20.2^d
Orange peel	Dried	380.0^a	4,232.3^a	177.7^a	27.7^b
	Blanched	194.4^b	2,445.5^b	133.9^b	38.8^a
	Frozen	56.9^c	828.5^c	49.3^c	26.1^b
	Fresh	54.4^c	756.5^c	47.7^d	26.2^b
Pineapple peel	Dried	18.8^a	1,342.8	42.6^a	15.0^b
	Blanched	13.1^b	733.4^b	32.3^b	19.8^a
	Frozen	1.3^c	152.4^c	6.5^c	9.9^c
	Fresh	18.8^a	95.0^d	0.6^d	6.5^d
Pomegranate skin	Dried	862.5^a	6,138.2^c	93.6^d	39.8^c
	Blanched	405.6^d	5,346.8^d	106.3^c	45.3^b
	Frozen	478.8^c	6,454.4^b	173.5^a	47.8^a
	Fresh	504.4^b	6,909.8^a	166.6^b	20.0^d

¹Flavonoids content ((quercetin equivalents (mg/100 g)), phenolic compounds (gallic acid equivalents (mg/100 g)), FRAP (ascorbic acid equivalent (0.1 g/100 ml)), and IC₅₀ (i.e., concentration of extract (mg/ml) needed to scavenge 50% of the DPPH radicals (mg/ml)) within the same fruit by-product and different treatment having different letters are significantly () different according to the LSD.