Effectiveness of 0, 1.5 and 3.0% gluconic acid (G) and/or 0 and 1.5% l
actic acid (L) solutions in reducing aerobic psychrotrophic bacteria p
late counts (PPCs) and lactic acid bacteria counts (LACs) on vacuum-pa
ckaged beef was investigated at 0, 14, 28 and 56 days of storage. Inst
rumental and visual color changes were evaluated up to 28 days. Steaks
treated with 1.5% L, plus 1.5% G or 3.0% G, solutions showed 2.0 and
2.5 log reductions (P<0.05) in PPCs compared to nontreated samples, re
spectively, at days 28 and 56. At 1.5%, G or L intervention for 0 and
14 days PPCs did not differ (P>0.05). However, PPCs were lower (P<0.05
) for samples treated with 1.5% L than with 1.5% G at 28 and 56 days o
f storage. The effect of G plus L in reducing (P<0.05) LACs was eviden
t at all storage periods. Inoculation with Lactobacillus fermentum (10
(4) colony forming units [CFU]I mi) resulted in higher (P<0.05) PPCs a
nd LACs at 28 and 56 days compared to noninoculated counterparts. Incr
easing G from 1.5 to 3.0% decreased (P<0.05) redness and increased (P<
0.05) yellowness at day 0. Samples treated with 1.5% L solution had nu
merically the lowest a values at days 0 and 14. This detrimental effe
ct was reduced (P<0.05) when 1.5% G was added in combination with L, b
ecause redness increased (P<0.05) at day 14. At 0 day, 1.5% L steaks s
howed the fastest (P<0.05) rate of color deterioration. At 14 days, th
e presence of L alone or in combination with 1.5 or 3% G resulted in s
teaks with slightly faster (P<0.05) color deterioration compared to st
eaks treated with G or not treated. At day 28, 3.0% G samples revealed
the fastest (P<0.05) color deterioration. This detrimental effect on
color was reduced (P<0.05) when G plus L was applied at 1.5%.