Edible Coatings of Aloe Vera Gel and Carnauba Wax Microparticles to Increase Strawberry (Fragaria ananassa) Shelf Life

Figures & data

Figure 1. Scanning electron micrographs of strawberry surface: (a) uncoated and (b) with preliminary coating (b). Magnification: 250x; Calibration bar: 100 $\mu \mathrm{m}$.

Figure 2. Scanning electron micrographs of strawberries coated for 60 seconds under different CWP concentrations: 0.3% (a), 0.4% (b), and 0.5% (c). Magnification: 250x; Calibration bar: 100 $\mu \mathrm{m}$.

Figure 3. Weight loss (%) of strawberry samples coated with different EC compositions of aloe vera gel and carnauba wax microparticles.

Table 1. Summary of analysis of variance (ANOVA) of percent weight loss of treatments.

Source of variation	Degrees of freedom	MS
		Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
Total	26
Treatment	8	0,08*	0,3*	1,4*	1,4*	1,35*	4,14*	4,55*
Aloe vera gel (A)	2	0,2*	1,05*	3,2*	3,83*	4,2*	16,4*	18,01*
Carnauba gel (B)	2	0,03*	0,2*	1,07*	0,9*	0,8*	0,11*	0,12*
Interaction (A*B)	4	0,01*	0,003*	0,67*	0,4*	0,21*	0,04*	0,03*
Error	18	0,005	0,003	0,003	0,01	0,004	0,0006	0,003

 * Significant at 5% probability by the F test.

Table 2. Weight loss (%) of the treatments.

Treatment/Days	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
T1	$1,26\pm 0,05$ $AB$c	$1,99\pm 0,06$ $A$b	$3,38\pm 0,12$ $Aa$	$3,69\pm 0,29$ $Aa$	$3,75\pm 0,14$ $Aa$	-	-
T2	$1,21\pm 0,01$ $ABe$	$1,92\pm 0,03$ ABd	$2,36\pm 0,07$ $Bc$	$3,24\pm 0,07$ $Bb$	$3,62\pm 0,04$ $Aa$	-	-
T3	$1,29\pm 0,17$ $Ad$	$1,78\pm 0,09$ $Bc$	$1,61\pm 0,02$ $Cc$	$2,31\pm 0,09$ $Cb$	$2,67\pm 0,04$ $Ba$	-	-
T4	$1,27\pm 0,05$ ABe	$1,62\pm 0,03$ Cd	$1,57\pm 0,05$ $CDd$	$2,16\pm 0,05$ $CDc$	$2,61\pm 0,02$ $Bb$	$2,75\pm 0,04$ $Aab$	$2,85\pm 0,11$ $Aa$
T5	$1,19\pm 0,05$ $ABf$	$1,47\pm 0,04$ CDe	$1,56\pm 0,04$ $CDe$	$2,13\pm 0,05$ $CDd$	$2,31\pm 0,05$ $Cc$	$2,48\pm 0,03$ $Bb$	$2,67\pm 0,07$ $Ba$
T6	$1,17\pm 0,04$ $ABd$	$1,30\pm 0,10$ $Ed$	$1,49\pm 0,02$ $CDc$	$2,08$ $\pm 0,09$ $CDb$	$2,25\pm 0,08$ $Cab$	$2,30\pm 0,03$ $Ca$	$2,43\pm 0,03$ $Ca$
T7	$1,07\pm 0,06$ BCe	$1,37\pm 0,05$ $DEd$	$1,42\pm 0,04$ $DEd$	$1,98\pm 0,03$ $Dc$	$2,17\pm 0,02$ $CDb$	$2,22\pm 0,03$ $Dab$	$2,32\pm 0,09$ $CDa$
T8	$0,96\pm 0,06$ CDf	$1,22\pm 0,04$ EFe	$1,35\pm 0,05$ $EFd$	$1,92\pm 0,04$ $Dc$	$2,04\pm 0,03$ $DEb$	$2,15\pm 0,04$ $Eab$	$2,20\pm 0,01$ $Da$
T9	$0,80\pm 0,06$ Df	$1,08\pm 0,04$ Fe	$1,21\pm 0,02Fd$	$1,60\pm 0,04$ $Ec$	$1,86\pm 0,06$ $Eb$	$1,98\pm 0,02$ $Fa$	$2,04\pm 0,03$ $Ea$

Means followed by at least one capital letter in the columns do not differ from each other, by Tukey’s test at 95% confidence.

The response variable was determined each day and when it exceeded the established specification, the analysis was stopped for the following days, which is why cells with a hyphen appear.

Table 4. pH of the treatments.

Treatment/Days	Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
T1	3,38 ±0,07 Ad	3,42 ± 0,03 Ad	3,51 ± 0,02 Ac	3,64 ± 0,03 Ab	3,69 ± 0,02 Aab	3,72 ± 0,02 Aa	-	-
T2	3,3 ± 0,01 Ad	3,37 ± 0,02 ABc	3,39 ± 0,03 Bc	3,45 ± 0,04 Bb	3,51 ± 0,01 Bb	3,65 ± 0,04 Ba	-	-
T3	3,34 ± 0,03 Ac	3,31 ± 0,03 BCc	3,36 ± 0,03 Bc	3,36 ± 0,02 CDc	3,44 ± 0,01 BCb	3,58 ± 0,04 Ba	-	-
T4	3,35 ±0,05 Ad	3,33 ± 0,02 ABd	3,34 ± 0,03 Bd	3,38 ± 0,01 Ccd	3,37 ± 0,04 CDcd	3,44 ± 0,02 Cbc	3,48 ± 0,03 Ab	3,69 ± 0,02 Aa
T5	3,35 ± 0,01 Ac	3,36 ± 0,02 ABc	3,36 ± 0,02 Bbc	3,37 ± 0,01 Cbc	3,39 ± 0,02 CDbc	3,39 ± 0,03 CDbc	3,43 ± 0,02 ABb	3,6 ± 0,05 Ba
T6	3,17 ± 0,04 Bd	3,29 ± 0,08 BCc	3,35 ± 0,01 Bbc	3,34 ± 0,01 CDbc	3,37 ± 0,01 Dbc	3,39 ± 0,02 CDbc	3,41 ± 0,02 Bab	3,51 ± 0,05 Ca
T7	3,13 ± 0,01 Be	3,22 ± 0,02 CDd	3,26 ± 0,02 Ccd	3,29 ± 0,03 Dcd	3,34 ± 0,01 Dc	3,39 ± 0,02 CDb	3,43 ± 0,02 ABab	3,44 ± 0,02 CDa
T8	3,1 ± 0,02 Be	3,18 ± 0,01 DEd	3,2 ± 0,05 CDcd	3,1 ± 0,02 Ecd	3,26 ± 0,04 Ec	3,35 ± 0,02 Db	3,38 ± 0,02 Bab	3,43 ± 0,02 Da
T9	3,08 ± 0,01 Bf	3,13 ± 0,02 Eef	3,18 ± 0,01 Dde	3,18 ± 0,03 Ede	3,22 ± 0,03 Ecd	3,28 ± 0,03 Ebc	3,31 ± 0,05 Cb	3,42 ± 0,03 Da

Means followed by at least one capital letter in the columns do not differ from each other, by Tukey’s test at 95% confidence. Means followed by at least one lowercase letter in the rows do not differ from each other, by Tukey’s test at 95% confidence.

The response variable was determined each day and when it exceeded the established specification, the analysis was stopped for the following days, which is why cells with a hyphen appear.

Figure 4. pH changes over time for strawberry samples coated with different EC compositions of aloe vera gel and carnauba wax microparticles.

Table 3. Summary of the analysis of variance (ANOVA) of pH of the treatments.

Source of variation	Degrees of freedom	MS
		Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
Total	26
Treatment	8	0,05*	0,03*	0,03*	0,06*	0,06*	0,07*	8,7*	9,28*
Aloe vera gel (A)	2	0,14*	0,09*	0,1*	0,15*	0,17*	0,024*	34,82*	37,10*
Carnauba gel (B)	2	0,02*	0,02*	0,01*	0,05*	0,04*	0,02*	0,009*	0,01*
Interaction (A*B)	4	0,01*	0,002*	0,006*	0,013*	0,01*	0,002*	0,0032*	0,007*
Error	18	0,0009	0,001	0,0006	0,0005	0,0006	0,01	0,0005	0,0008

 * Significant at 5% probability by the F test.

Table 5. Summary of the analysis of variance (ANOVA) of the percentage of Brix degrees of the treatments.

Source of variation	Degrees of freedom	MS
		Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
Total	26
Treatment	8	0,08 *	0,5 *	2,19 *	3,05 *	5,7 *	6,34 *	73,4 *	80,3 *
Aloe vera gel (A)	2	0,16 *	1,26 *	7,26 *	8,6 *	19,15 *	21,32 *	290,3 *	318,62 *
Carnauba gel (B)	2	0,06 *	0,35 *	1,14 *	2,14 *	2,75 *	3,6 *	1,9 *	1,52 *
Interaction (A*B)	4	0,05 *	0,18 *	0,2 *	0,74 *	0,44 *	0,23 *	0,71 *	0,45 *
Error	18	0,009	0,03	0,06	0,03	0,09	0,05	0,02	0,01

 * Significant at 5% probability by the F test.

Table 6. Brix degrees of the treatments.

Treatment/Days	Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
T1	$6,58\pm 0,08$ $AB$f	$7,97\pm 0,15$ $A$e	$9,60\pm 0,36$ $A$d	$10,67\pm 0,35$ $Ac$	$11,37\pm 0,25$ $Ab$	$12,10\pm 0,36$ $Aa$	-	-
T2	$6,76\pm 0,05$ $Ad$	$7,27\pm 0,15$ $Bd$	$8,77\pm 0,32$ Bc	$9,00\pm 0,10$ $Bc$	$10,83\pm 0,15$ $ABb$	$11,40\pm 0,36$ $Ba$	-	-
T3	$6,50\pm 0,10$ $ABCd$	$7,07\pm 0,12$ $BCc$	$8,60\pm 0,20$ $Bb$	$8,73\pm 0,15$ $Bb$	$10,60\pm 0,20$ $ABa$	$11,00\pm 0,20$ $Ba$	-	-
T4	$6,77\pm 0,15$ Ae	$7,00\pm 0,20$ BCDe	$8,27\pm 0,31$ Bd	$8,20\pm 0,20$ $Cd$	$10,40\pm 0,40$ $Bc$	$10,93\pm 0,12$ $Bbc$	$11,53\pm 0,12$ $Aab$	$11,73\pm 0,12$ $Aa$
T5	$6,43\pm 0,06$ $BCe$	$7,00\pm 0,00$ $BCDe$	$8,13\pm 0,12$ BCd	$8,07\pm 0,12$ $Cd$	$9,07\pm 0,64$ $Cc$	$10,00\pm 0,20$ $Cb$	$10,53\pm 0,23$ $Bab$	$11,00\pm 0,20$ $Ba$
T6	$6,47\pm 0,12$ $BCg$	$7,00\pm 0,20$ $BCDfg$	$7,47\pm 0,31$ $CDef$	$8,00\pm 0,20$ $Cde$	$8,47$ $\pm 0,31$ $CDcd$	$9,07\pm 0,31$ $Dbc$	$9,60\pm 0,20$ $Cab$	$10,20\pm 0,20$ $Ca$
T7	$6,40\pm 0,10$ BCf	$6,80\pm 0,20$ BCDf	$7,40\pm 0,20$ $De$	$7,93\pm 0,12$ $CDd$	$8,33\pm 0,12$ $CDd$	$8,87\pm 0,12$ $DEc$	$9,33\pm 0,23$ $Cb$	$9,93\pm 0,12$ $Ca$
T8	$6,37\pm 0,06$ BCf	$6,73\pm 0,12$ CDf	$7,13\pm 0,12$ De	$7,47\pm 0,12$ $DEe$	$7,93\pm 0,12$ $Dd$	$8,33\pm 0,23$ $EFc$	$8,87\pm 0,12$ $Db$	$9,47\pm 0,12$ $Da$
T9	$6,30\pm 0,10$ Ce	$6,53\pm 0,23$ De	$7,07\pm 0,12$ Dd	$7,33\pm 0,12Ed$	$7,80\pm 0,20$ $Dc$	$8,07\pm 0,12$ $Fc$	$8,53\pm 0,12$ $Db$	$9,00\pm 0,20$ $Ea$

Means followed by at least one capital letter in the columns do not differ from each other, by Tukey’s test at 95% confidence.

Means followed by at least one lowercase letter in the rows do not differ from each other, by Tukey’s test at 95% confidence.

The response variable was determined each day and when it exceeded the established specification, the analysis was stopped for the following days, which is why cells with a hyphen appear.

Table 7. Summary of the analysis of variance (ANOVA) of acidity of the treatments.

Source of variation	Degrees of freedom	MS
		Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
Total	26
Treatment	8	0,003*	0,005*	0,002*	0,0003*	0,003*	0,003*	0,2*	0,10*
Aloe vera gel (A)	2	0,007*	0,012*	0,006*	0,0008*	0,0001*	0,0004*	0,42*	0,41*
Carnauba gel (B)	2	0,0002*	0,003*	0,0003*	0,005*	0,003*	0,003*	0,0002*	0,00004*
Interaction (A*B)	4	0,004*	0,001*	0,0001*	0,003*	0,004*	0,004*	0,00009*	0,0001*
Error	18	0,0004	0,001	0,0002	0,0001	0,0001	0,00002	0,0001	0,00004

 * Significant at 5% probability by the F test.

Table 8. Acidity of the treatments.

Treatment/Days	Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
T1	0,56 ± 0,01 ABa	0,48 ± 0,01 ABCb	0,46 ± 0,01 ABCbc	0,44 ± 0,02 Bcd	0,43 ± 0,0 ABd	0,42 ± 0,0 Ad	-	-
T2	0,5 ± 0,04 Ca	0,5 ± 0,06 ABCa	0,47 ± 0,01 ABa	0,36 ± 0,02 Db	0,32 ± 0,02 Db	0,32 ± 0,0 Db	-	-
T3	0,57 ± 0,01 ABa	0,51 ± 0,0 ABb	0,47 ± 0,0 ABCc	0,47 ± 0,01 Ac	0,43 ± 0,0 Ad	0,43 ± 0,0 Ad	-	-
T4	0,55 ± 0,01 ABCa	0,48 ± 0,01 ABCb	0,47 ± 0,0 ABCb	0,43 ± 0,01 BCc	0,37 ± 0,02 Ccd	0,37 ± 0,0 Cd	0,37 ± 0,03 Ad	0,39 ± 0,01 Ad
T5	0,59 ± 0,03 Aa	0,54 ± 0,004 Aab	0,49 ± 0,04 Ab	0,4 ± 0,01 Cc	0,4 ± 0,01 ABCc	0,39 ± 0,01 Bc	0,39 ± 0,01 Ac	0,38 ± 0,01 Ac
T6	0,53 ± 0,01 ABCa	0,52 ± 0,0 ABa	0,47 ± 0,01 ABb	0,42 ± 0,01 BCc	0,39 ± 0,01 BCd	0,39 ± 0,01 Bd	0,38 ± 0,0 Ad	0,37 ± 0,0 ABd
T7	0,5 ± 0,01 Ca	0,44 ± 0,01 BCb	0,42 ± 0,0 Cbc	0,4 ± 0,01 Ccd	0,38 ± 0,01 Cde	0,37 ± 0,0 Ce	0,36 ± 0,01 Ae	0,35 ± 0,01 Ce
T8	0,5 ± 0,02 Ca	0,42 ± 0,06 Cb	0,42 ± 0,01 Cb	0,41 ± 0,01 BCb	0,38 ± 0,02 Cb	0,38 ± 0,0 BCb	0,37 ± 0,0 Ab	0,36 ± 0,0 BCb
T9	0,51 ± 0,01 BCa	0,47 ± 0,02 ABCb	0,43 ± 0,01 BCc	0,41 ± 0,01 BCcd	0,4 ± 0,01 ABCcde	0,39 ± 0,01 Bdef	0,37 ± 0,01 Aef	0,36 ± 0,0 BCf

Means followed by at least one capital letter in the columns do not differ from each other, by Tukey’s test at 95% confidence.

Means followed by at least one lowercase letter in the rows do not differ from each other, by Tukey’s test at 95% confidence.

The response variable was determined each day and when it exceeded the established specification, the analysis was stopped for the following days, which is why cells with a hyphen appear.

Table 9. Summary of the analysis of variance (ANOVA) of the ripening index of the treatments.

Source of variation	Degrees of freedom	MS
		Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
Total	26
Treatment	8	1,99*	5,11n.s.	6,92*	19,92*	58,97*	62,73*	531,96*	579,10*
Aloe vera gel (A)	2	1,77*	6,88n.s.	19,00*	37,73*	129,91*	133,58*	2088,98*	2303,1*
Carnauba gel (B)	2	0,43*	8,5n.s.	7,42*	21,09*	41,47*	58,10*	22,79*	8,78*
Interaction (A*B)	4	2,89*	2,53n.s.	0,64*	10,43*	32,25*	29,62*	8,04*	2,28*
Error	18	0,33	1,29	0,59	0,54	2,15	0,71	0,78	0,39

* Significant at 5% probability by the F test.

n.s. not significant at 5% probability by the F test.

Table 10. Treatment ripening index.

Treatment/Days	Day 0	Day 2	Day 4	Day 6	Day 8	Day 10	Day 12	Day 14
T1	11,75 ± 0,26 BCf	16,74 ± 0,49Ae	20,91 ± 0,52 Ad	24,39 ± 1,05 Ac	26,73 ± 0,8 BCb	28,85 ± 0,73 Ba	-	-
T2	13,67 ± 1,17 Ad	14,74 ± 1,5 ABCd	18,66 ± 0,44 Bc	24,88 ± 1,07 Ab	33,53 ± 2,32 Aa	35,56 ± 1,35 Aa	-	-
T3	11,51 ± 0,49 BCd	13,82 ± 0,15 ABCc	18,48 ± 0,55 BCb	18,47 ± 0,34 BCb	24,71 ± 0,44 BCDa	25,54 ± 0,61 Ca	-	-
T4	12,34 ± 0,37 ABCd	14,62 ± 0,59 ABCcd	17,72 ± 0,5 BCDbc	19,3 ± 0,16 BCb	28,22 ± 2,84 CDEa	29,85 ± 0,65 Ba	31,6 ± 2,27 Aa	30,14 ± 0,44 Aa
T5	10,89 ± 0,66 Ce	12,94 ± 0,89 Ce	16,68 ± 1,42 BCDc	20,12 ± 0,62 Bc	22,73 ± 1,21 DEc	25,67 ± 0,81 Cb	27,31 ± 0,51 Bab	28,83 ± 1,06 ABa
T6	12,15 ± 0,46 ABCf	13,37 ± 0,29 BCf	15,94 ± 0,11 CDe	19,18 ± 0,62 BCd	21,65 ± 1,14 DEc	23,56 ± 1,14 CDbc	25,18 ± 0,69 BCDab	27,37 ± 0,68 Ba
T7	12,69 ± 0,45 ABg	15,5 ± 0,41 ABCf	17,44 ± 0,52 BCDe	19,78 ± 0,99 BCd	21,95 ± 0,58 DEc	24,08 ± 0,51 CDb	25,98 ± 0,55 Bb	28,19 ± 1,11 BCa
T8	12,88 ± 0,63 ABf	16,27 ± 2,6 ABe	16,83 ± 0,64 BCDe	18,43 ± 0,59 BCde	20,78 ± 1,1 DEcd	22,05 ± 0,77 DEbc	24,12 ± 0,14 CDab	26,23 ± 0,45 CDa
T9	12,46 ± 0,17 ABCf	13,85 ± 0,96 ABCf	16,41 ± 0,63 CDe	17,85 ± 0,58 Cde	19,46 ± 0,84 Ecd	20,73 ± 0,65 Ec	23 ± 0,91 Db	25,05 ± 0,56 Da

Means followed by at least one capital letter in the columns do not differ from each other, by Tukey’s test at 95% confidence.

Means followed by at least one lowercase letter in the rows do not differ from each other, by Tukey’s test at 95% confidence.

The response variable was determined each day and when it exceeded the established specification, the analysis was stopped for the following days, which is why cells with a hyphen appear.

Figure 5. Ripening index for strawberry samples coated with different EC compositions of aloe vera gel and carnauba wax microparticles.

Figure 6. Sensory attributes of strawberries with different coating formulations.

Table 11. Summary of the analysis of variance (ANOVA) of the global perception and attributes of the treatments.

Source of variation	Freedom degrees	CM
		Appearance	Smell	Taste	Global
Total	247
Treatments	3	6,63*	3,68n.s.	3,88n.s.	4,03n.s.
Blocks	61	5,20*	6,56*	4,80*	3,57*
Experimental error	183	2,62	2,36	3,08	1,91

* Significant at 5% probability by the F test.

n.s. not significant at 5% probability by the F test.

Table 12. Appearance of the treatments.

Sample	Code	Appearance
Control	149	6,71 ± 2,20 ab
T9 (0)	342	7,29 ± 2,07 a
T9 (3)	267	6,94 ± 1,78 ab
T9 (6)	581	6,53 ± 1,83 b

Means followed by at least one lowercase letter do not differ from each other, at a 5% probability by Tukey’s test.

Table 13. Global perception and attributes of the treatments.

Sample	Code	Global	Smell	Taste
Control	149	7,31 ± 1,55	6,45 ± 1,74	6,90 ± 1,91
T9 (0 days)	342	6,59 ± 1,57	6,35 ± 1,92	6,48 ± 1,85
T9 (3 days)	267	6,76 ± 1,28	6,17 ± 1,84	6,38 ± 1,62
T9 (6 days)	581	6,79 ± 1,66	6,76 ± 1,88	6,38 ± 2,14

Data Availability Statement

The data to support the results and conclusions of this study is presented within the article. Detailed data is available upon request.