Effect of Oxygen-Reducing Atmospheres on the Safety of Packaged Shelled Brazil Nuts during Storage

Table 1

Effect of O₂ reducing atmospheres on aflatoxins, lipids, microorganisms and consumers acceptance of packaged shelled Brazil nuts during storage.

Storage		Total fungi count*(cfu·g^−1)	Aspergillus toxigenic strains	m.c.^a		Aflatoxins^b (μg·kg^−1)	Lipid stability (mg·kg^−1)^c	Brazil nuts sensory attributes (scores)^d
Atmosphere	Day			(%)	(diff.%)^e			AP	CO	FI	RA	SR	OD
GROUP I—Control^f
Air
	Initial	1.83 × 10^4	(+) A. flavus; A. parasiticus ^h	6.5		<0.36	7.24 ± 0.9	4	4	4	4	4	4
	Final	2.69 × 10^7	(+) A. flavus; A. parasiticus	8.1	(+0.6%)	<1.89	9.98 ± 1.6	2	3	3	2	3	2
Vacuum
	Initial	1.83 × 10^4	(+) A. flavus; A. parasiticus	4.2		<0.36	7.33 ± 0.4	4	4	4	4	4	4
	Final	0.70 × 10	(+) A. flavus; A. parasiticus	4.2	(no diff.)	<0.36	7.24 ± 1.1	4	4	4	4	4	4
GROUP II^i
Air
	1	1.83 × 10^4	(+) A. flavus; A. parasiticus	6.5		15.00	7.33 ± 0.1	4	4	4	4	4	4
	30	2.96 × 10^5	(+) A. flavus; A. parasiticus	7.1		15.81	8.25 ± 0.2	4	3	4	3	3	3
	60	6.30 × 10^6	(+) A. flavus; A. parasiticus	7.1	(+0.6%)	16.85	9.24 ± 0.7	3	3	3	1	3	2
Vacuum
	1	1.83 × 10^4	(+) A. flavus; A. parasiticus	4.2		15.00	6.85 ± 0.5	4	4	4	4	4	4
	30	0.56 × 10	NG^j	4.2		14.88	7.24 ± 0.8	4	4	4	4	4	4
	60	0.10 × 10	NG	4.2	(−2.3%)	14.95	7.24 ± 0.5	4	5	5	4	4	4
Ozone
	1	NG	NG	5.0		<0.36	7.25 ± 1.2	4	4	4	4	4	4
	30	NG	NG	4.9		<0.36	7.24 ± 0.6	4	4	4	4	4	4
	60	NG	NG	4.7	(−1.8%)	<0.36	7.84 ± 0.6	4	5	4	4	4	4
Ozone + vacuum
	1	NG	NG	3.1		<0.36	6.25 ± 0.2	4	4	4	4	4	4
	30	NG	NG	3.3		<0.36	7.04 ± 0.7	4	4	4	4	4	4
	60	NG	NG	3.0	(−3.5%)	<0.36	7.25 ± 0.5	4	4	5	4	4	4
Carbon dioxide
	1	1.83 × 10^4	(+) A. flavus; A. parasiticus	6.5		15.00	7.25 ± 0.2	4	4	4	4	4	4
	30	NG	NG	7.0		14.90	7.24 ± 1.1	4	4	4	4	4	4
	60	NG	NG	7.0	(+0.5%)	14.92	7.90 ± 0.6	3	4	4	4	4	3
Oxygen absorber pad
	1	1.83 × 10^4	(+) A. flavus; A. parasiticus	6.5		15.00	7.25 ± 2.2	4	4	4	4	4	4
	30	2.6 × 10	NG	6.5		14.90	7.90 ± 1.7	4	4	4	4	4	4
	60	NG	NG	6.5	(no diff.)	15.00	8.20 ± 0.6	4	3	4	4	4	3
Oxygen  absorber pad  +  vacuum
	1	1.8 × 10^4	(+) A. flavus; A. parasiticus	4.0		15.00	7.00 ± 2.2	4	4	4	4	4	4
	30	NG	NG	3.9		15.01	7.24 ± 1.5	4	4	4	4	4	4
	60	NG	NG	4.3	(−2.2%)	14.99	7.24 ± 1.5	4	3	5	4	4	3
GROUP III^k
Ozone
	1	NG	NG	5.6		<0.36	7.56 ± 0.9	4	4	4	4	4	4
	30	NG	NG	5.4		<0.36	7.94 ± 0.2	4	4	4	4	4	4
	60	NG	NG	5.2	(−1.6%)	<0.36	7.99 ± 0.5	4	4	3	4	4	4
Ozone + vacuum
	1	NG	NG	4.0		<0.36	7.95 ± 0.4	4	4	4	4	4	4
	30	NG	NG	3.9		<0.36	7.94 ± 1.2	4	4	4	4	4	4
	60	NG	NG	3.7	(−3.2%)	<0.36	8.54 ± 0.6	4	3	4	4	4	4

^am.c.: moisture content; ^baflatoxin total: AFB₁+AFB₂+AFG₁+AFG₂ (method LOQ: 0.350 μg/kg); ^cin malondialdehyde; ^dvalues as mean scores of 18 individual panellists [AP: nut appearance; CO: color; FI: firmness; RA: rancid odour; SR: slicing resistant; OD: strange odor (5: like very much, 4: like, 3: neither like nor dislike, 2: dislike and 1: dislike very much)]; ^ediff: m.c. difference (+) increased or (−) reduction; ^fno aflatoxin spiked (nuts total AFL < method LOQ = 0.36 μg·kg⁻¹); ^htoxigenic Aspergillus strains isolated in AFPA media; ⁱ15 μg·kg⁻¹ AFLs spiked and 6.5% m.c.; ^jNG: no growth; ^kBrazil nuts naturally aflatoxin contaminated = 10.61 μg·kg⁻¹ and 7.2% m.c. *The genera and species more often isolated from the Control Brazil nuts were Acremonium sp; A. ochraceus; A. nomius; Cladosporium sp.; P. corylophilum, and Rhizopus sp. followed by A. niger; A. parasiticus; A. versicolor, and P. crustosum.