Shelf Life, Fruit Quality and Safety of Banana (Musa Species) Ripened through Traditional Ripening Techniques in Nigeria

Figures & data

Figure 1. Measurement of the ripening period of banana using the epicarp color and number of days after exposure to different local induced ripening techniques of (a) Musa acuminata and (b) Musa balbisiana.

Key: Color codes; 0 = Black and dark golden rod (rotten), 1 = Khaki, 2 dark green, 3 = Forest green, 4 = lime green, 5 = olive drab, 6 = yellow green, 7 = yellow.Treatments; H = Immersion in hot water, CD2 = 2 g dry CaC₂ for 2 kg FW of banana, CD5 = 5 g dry CaC₂ for 2 kg FW of banana, CD10 = 10 g dry CaC₂ for 2 kg FW of banana, CW2 = 2 g CaC₂/100 ml water for 2 kg FW of banana, CW5 = 5 g CaC₂/100 ml water for 2 kg FW of banana, CW10 = 10 g CaC₂/100 ml water for 2 kg FW of banana, NB = banana wrapping in nylon bag, SB = banana wrapping in Sack bag, SL = banana under direct Sunlight, CTR = Control.

Figure 2. Musa acuminata at 3 days after exposure to different local induced ripening treatments

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry CaC₂ for 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml water for 2 kg FW of banana treatment, CW10 = 10 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Figure 3. Musa balbisiana at 3 days after exposure to different local induced ripening treatments

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry CaC₂ for 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW10 = 10 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Figure 4. Musa acuminata at 7 days after exposure to different local induced ripening treatments

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry for CaC₂ 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW10 = 10 g of wet CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Figure 5. Musa balbisiana at 7 days after exposure to different induced local ripening treatments

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry CaC₂ for 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of wet CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW10 = 10 g of wet CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Figure 6. (a) Musa acuminata and (b) Musa balbisiana at 9 days after exposure to different local induced ripening treatments

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry CaC₂ for 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW10 = 10 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Table 1. Number of days and degree of softness of the fruits after exposure to the experimental treatments

	Days after harvest
	0	1	2	3	4	5	6	7	8	9
M. acuminata
H	-	-	-	-	-	+	+	+	++	++
CD2	-	+	+	++	++	++	+++	+++	+++	+++
CD5	-	+	+	++	++	++	+++	+++	+++	+++
CD10	-	+	+	++	++	++	+++	+++	+++	+++
CW2	-	+	+	++	++	++	+++	+++	+++	+++
CW5	-	+	+	++	++	++	+++	+++	+++	+++
CW10	-	+	+	++	++	++	+++	+++	+++	+++
NB	-	-	-	-	-	+	+	+	+	++
SB	-	-	-	+	+	+	+	+	++	++
SL	-	-	-	+	+	+	+	+	+	+
CTR	-	-	-	-	+	+	+	+	+	++
M. balbisiana
H	-	-	-	-	-	+	+	+	++	++
CD2	-	+	+	+	++	++	++	+++	+++	+++
CD5	-	+	+	+	++	++	++	+++	+++	+++
CD10	-	+	+	++	++	++	++	+++	+++	+++
CW2	-	+	+	++	++	++	++	+++	+++	+++
CW5	-	+	+	++	++	++	++	+++	+++	+++
CW10	-	+	+	++	++	++	++	+++	+++	+++
NB	-	-	-	-	-	+	+	+	++	++
SB	-	-	-	-	-	+	++	++	++	++
SL	-	-	-	-	+	++	++	++	++	++
CTR	-	-	-	-	+	+	++	++	++	++

Key: – = Not soft at all, + = Soft, ++ = Very soft, +++ = Very very soft.

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry CaC₂ for 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW10 = 10 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Table 2. Number of days and the degree of spoilage observed in the fruits after treatment with different local induced ripening conditions

	Days after harvest
	0	1	2	3	4	5	6	7	8	9
M. acuminata
H	-	-	-	+	+	+	+	++	++	++
CD2	-	-	-	-	+	+	++	++	++	++
CD5	-	-	-	-	+	+	++	++	++	++
CD10	-	-	-	-	+	+	++	++	++	++
CW2	-	-	-	-	+	+	++	++	++	++
CW5	-	-	-	-	+	+	++	++	++	++
CW10	-	-	-	-	+	+	++	++	++	++
NB	-	-	-	-	-	-	-	-	-	-
SB	-	-	-	-	-	-	-	-	-	-
SL	-	-	-	-	-	-	-	-	-	-
CTR	-	-	-	-	-	-	-	-	-	-
M. balbisiana
H	-	-	+	+	+	+	+	++	++	++
CD2	-	-	-	-	+	+	+	++	++	++
CD5	-	-	-	-	+	+	+	++	++	++
CD10	-	-	-	-	+	+	+	++	++	++
CW2	-	-	-	-	+	+	+	++	++	++
CW5	-	-	-	-	+	+	+	++	++	++
CW10	-	-	-	-	+	+	+	++	++	++
NB	-	-	-	-	-	-	-	-	-	-
SB	-	-	-	-	-	-	-	-	-	-
SL	-	-	-	-	-	-	-	-	-	-
CTR	-	-	-	-	-	-	-	-	-	-

KEY: – = Negative (No spoilage), + = Positive (Beginning of Spoilage), ++ = Increased spoilage.

H = Hot water treatment, CD2 = 2 g of dry CaC₂ for 2 kg FW of banana treatment, CD5 = 5 g of dry CaC₂ for 2 kg FW of banana treatment, CD10 = 10 g of dry CaC₂ for 2 kg FW of banana treatment, CW2 = 2 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW5 = 5 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, CW10 = 10 g of CaC₂/100 ml of water for 2 kg FW of banana treatment, NB = Nylon bag treatment, SB = Sack bag treatment, SL = Sunlight treatment, CTR = Control.

Table 3. Total phenols content of banana after exposure to different local induced ripening conditions

	M. acuminata (mg/100 g FW)			M. balbisiana (mg/100 g FW)
	2 DAH	5 DAH	p-value	2 DAH	5 DAH	p-value
FD	148.83^b	445.09 ^c	0.021	171.73^d	206.78^b	0.085
H	115.65^b	413.55 ^cd	0.006	220.79 ^cd	357.48^ab	0.219
CD2	280.28^ab	686.92^b	<0.001	630.84^a	322.43^b	<0.001
CD5	278.74^a	476.64 ^c	0.014	248.83 ^cd	571.26^a	0.042
CD10	290.89^a	380.37 ^cd	0.634	297.94^bd	255.84^b	0.633
CW2	332.94^a	911.21^a	<0.001	382.01^bc	231.31^b	0.128
CW5	282.24^ab	459.11 ^c	0.046	360.98^bd	420.56^a	0.421
CW10	231.31^ab	280.37 ^cd	0.132	245.33 ^cd	287.38^b	0.677
NB	189.25^ab	452.11 ^c	0.002	175.23^d	161.21^b	0.429
SB	213.64^ab	253.97^d	0.082	204.81 ^cd	243.46	0.071
SL	318.93^a	445.09 ^c	0.249	455.61^ab	357.48^ab	0.103
CTR	183.64^ab	210.24^d	0.126	157.48^d	117.54^b	<0.001
p-value	0.123	0.009		<0.001	0.043

DAH: days after harvest. Means with similar alphabetic superscripts in the same column do not differ from each other (p > 0.05).

Key: H = Immersion in hot water, CD2 = 2 g dry CaC₂ for 2 kg FW of banana, CD5 = 5 g dry CaC₂ for 2 kg FW of banana, CD10 = 10 g dry CaC₂ for 2 kg fresh weigh of banana, CW2 = 2 g CaC₂/100 ml water for 2 kg FW of banana, CW5 = 5 g CaC₂/100 ml water for 2 kg FW of banana, CW10 = 10 g CaC₂/100 ml water for 2 kg FW of banana, NB = banana wrapped in nylon bag, SB = banana wrapped in sack bag, SL = banana kept under direct sunlight, CTR = Control.

Table 4. The ascorbic acid content of banana after exposure to different local induced ripening conditions

	M. acuminata (mg/100 g FW)			M. balbisiana (mg/100 g FW)
	2 DAH	5 DAH	p-value	2 DAH	5 DAH	p-value
FD	14.86^b	10.45 ^c	0.084	55.90^b	41.34^b	0.149
H	41.07^b	68.07 ^c	0.153	18.60^b	21.31^b	0.014
CD2	250.03^b	689.31^a	<0.001	154.14^a	686.55^a	<0.001
CD5	261.03^a	476.55^b	<0.001	194.48^a	489.31^a	0.003
CD10	113.79^a	632.76^a	<0.001	323.80^a	686.55^a	0.003
CW2	122.76^a	689.31^a	<0.001	301.38^a	512.41^a	0.254
CW5	331.03^a	684.14^a	0.027	265.52^a	494.50^a	0.147
CW10	236.21^a	652.59^a	0.003	363.80^a	618.38^a	0.270
NB	9.82^b	11.34 ^c	0.138	25.00^b	18.38^b	0.113
SB	16.07^b	19.76 ^c	0.645	29.24^b	19.07^b	0.391
SL	21.70^b	16.21 ^c	0.329	33.79^b	11.20^b	0.735
CTR	26.21^b	18.23 ^c	0.245	13.97^b	17.54^b	0.385
p-value	<0.001	0.002		<0.001	<0.001

DAH: days after harvest. Means with similar alphabetic superscripts in the same column do not differ from each other (P > 0.05).

Key: H = Immersion in hot water, CD2 = 2 g dry CaC₂ for 2 kg FW of banana, CD5 = 5 g dry CaC₂ for 2 kg FW of banana, CD10 = 10 g dry CaC₂ for 2 kg FW of banana, CW2 = 2 g CaC₂/100 ml water for 2 kg FW of banana, CW5 = 5 g CaC₂/100 ml water for 2 kg FW of banana, CW10 = 10 g CaC₂/100 ml water for 2 kg FW of banana, NB = banana wrapped in nylon bag, SB = banana wrapped in sack bag, SL = banana kept under direct sunlight, CTR = Control.

Table 5. Total sugar concentration in banana after exposure to the experimental conditions

	M. acuminata (g/100 g FW)			M. balbisiana (g/100 g FW)
	2 DAH	5 DAH	p-value	2 DAH	5 DAH	p-value
FD	10.44^b	18.08^b	0.162	21.14^b	11.84 ^c	0.213
H	6.18^b	29.71^b	<0.001	23.76^b	55.00^ab	0.039
CD2	29.8^a	69.56^a	0.025	47.91^a	60.12^ab	0.092
CD5	33.91^a	59.71^a	0.041	47.03^a	67.32^a	0.065
CD10	46.33^a	78.69^a	0.006	43.21^a	59.85^a	0.037
CW2	47.64^a	43.69^a	0.318	47.26^a	69.13^a	0.081
CW5	36.91^a	69.56^a	0.011	47.41^a	48.83^a	0.742
CW10	47.52^a	75.51^a	0.038	41.41^a	68.31^a	0.048
NB	8.83^b	22.57^b	0.004	35.63^a	32.64^bc	0.574
SB	4.31^b	18.28^b	<0.001	10.67^b	47.52^a	0.026
SL	7.21^b	16.56^b	<0.001	19.52^b	12.77 ^c	0.137
CTR	4.84^b	12.45^b	0.021	15.85^b	17.45 ^c	0.558
p-value	<0.001	0.402		0.352	0.051

DAH: days after harvest. Means with similar alphabetic superscripts in the same column do not differ from each other (P > 0.05).

Key: H = Immersion in hot water, CD2 = 2 g dry CaC₂ for 2 kg FW of banana, CD5 = 5 g dry CaC₂ for 2 kg FW of banana, CD10 = 10 g dry CaC₂ for 2 kg FW of banana, CW2 = 2 g CaC₂/100 ml water for 2 kg FW of banana, CW5 = 5 g CaC₂/100 ml water for 2 kg FW of banana, CW10 = 10 g CaC₂/100 ml water for 2 kg FW of banana, NB = banana wrapped in nylon bag, SB = banana wrapped in sack bag, SL = banana kept under direct sunlight, CTR = Control.

Table 6. Arsenic concentration in fruit endocarp after exposure to different calcium carbide concentration to induce ripening

Ripening method	Raw CaC2 (mg/kg)	Musa acuminata (mg/kg)	Musa balbisiana (mg/kg)	p-value
Raw CaC2	10.12	-	-	-
CD2	-	0.058^a	0.147^a	0.123
CD5	-	0.071^a	0.155^a	0.319
CD10	-	0.083^a	0.164^a	0.069
CW2	-	0.026^a	0.072^a	0.274
CW5	-	0.033^a	0.084^a	0.116
CW10	-	0.051^a	0.113^a	0.046
CTR		<0.001^b	<0.001^b	NA
p-value	-	<0.001	<0.001	-

Means with similar alphabetic superscripts in the same column do not differ from each other (P > 0.05).

Key: H = Immersion in hot water, CD2 = 2 g dry CaC₂ for 2 kg FW of banana, CD5 = 5 g dry CaC₂ for 2 kg FW of banana, CD10 = 10 g dry CaC₂ for 2 kg FW of banana, CW2 = 2 g CaC₂/100 ml water for 2 kg FW of banana, CW5 = 5 g CaC₂/100 ml water for 2 kg FW of banana, CW10 = 10 g CaC₂/100 ml water for 2 kg FW of banana, NB = banana wrapped in nylon bag, SB = banana wrapped in sack bag, SL = banana kept under direct sunlight, CTR = Control.