Chemical Composition, Physicochemical and Technological Properties of Selected Fruit Peels as a Potential Food Source

Figures & data

Table 1. Proximate composition of selected fruit peel powders

Property	Sample
	AP	PP	PFP	OP
Yield*	62.21 ± 0.45^a	17.07 ± 0.17^d	14.70 ± 0.07^c	50.39 ± 1.71^b
Moisture (%)	37.79 ± 0.45^c	82.93 ± 0.17^a	85.21 ± 0.01^a	49.61 ± 1.71^b
Ash (%)	2.94 ± 0.05^c	4.56 ± 0.03^b	6.32 ± 0.08^a	4.92 ± 0.04^b
Protein (%)	0.25 ± 0.01^a	0.17 ± 0.03^b	0.17 ± 0.01^b	0.28 ± 0.00^a
Lipid (%)	35.22 ± 0.58^a	0.99 ± 0.16^c	0.47 ± 0.03^c	16.20 ± 0.18^b
Fiber (%)	53.14 ± 0.17^a	11.66 ± 0.23^d	32.85 ± 0.02^b	20.14 ± 0.88^c
Carbohydrates (%)	7.98 ± 0.66^c	82.61 ± 0.10^a	59.01 ± 1.28^b	58.62 ± 0.42^b

Mean ± SD. Values followed by different letters in the same row are significantly different (p < 0.05) according to Tukey’s test (calculations were done in dry basis except for yield and moisture%)

Table 2. Physicochemical properties of selected fruit peels powders

Sample	pH	Color values
		L*	a*	b*
AP	6.23 ± 0.02^a	55.31 ± 0.24^d	8.25 ± 0.03^a	14.80 ± 0.09^c
PP	4.24 ± 0.01^b	60.79 ± 0.60^c	6.10 ± 0.04^b	22.76 ± 0.06^b
PFP	4.46 ± 0.03^b	82.17 ± 0.08^a	2.5 ± 0.12^c	15.68 ± 0.07^c
OP	4.30 ± 0.01^b	77.26 ± 0.82^b	−2.76 ± 0.01^d	25.74 ± 0.71^a

Mean ± SD. Values followed by different letters in the same column are significantly different (p < 0.05) according to Tukey’s test

Table 3. Technological properties of selected peels powders

Property	Sample
	AP	PP	PFP	OP
Bulk density (g/ml)	0.29 ± 0.00^b	0.39 ± 0.01^a	0.29 ± 0.00^b	0.37 ± 0.01^a
Swelling Capacity (ml/g)	4.36 ± 0.29^c	7.57 ± 0.29^b	16.94 ± 0.47^a	8.98 ± 0.14^b
Water Holding Capacity (ml/g)	6.33 ± 0.14	4.30 ± 0.29	9.63 ± 0.21	6.33 ± 0.14
Oil Holding Capacity (ml/g)	3.10 ± 0.16	1.90 ± 0.08	2.85 ± 0.05	2.40 ± 0.03
Emulsifying Capacity %	36.26 ± 0.20^a	28.00 ± 0.00^b	28.14 ± 1.03^b	27.47 ± 0.53^b
Emulsifying Stability %	41.76 ± 0.97^a	28.00 ± 0.00^b	29.17 ± 0.00^b	25.33 ± 1.33^c
Least gelation concentration %	>10	9.00 ± 0.00	8.00 ± 0.00	3.00 ± 0.00
Foaming capacity %	8.47 ± 0.29^d	22.67 ± 0.67^a	10.00 ± 0.00^c	16.67 ± 1.76^b
Foam stability%	11.84 ± 0.40^b	8.84 ± 0.25^c	18.28 ± 0.96^a	12.26 ± 1.24^b

Mean ± SD. Values followed by different letters in the same row are significantly different (p < 0.05) according to Tukey’s test

Figure 1. Appearance of Peel Powders

Figure 2. Test for find least gelation concentration (peel concentrations were increased from right to left as 2 to 10%)