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| Product | Coating material | Antimicrobial compound | Target microorganism | Inoculation technique | Conditions | Results | Reference |
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| Sliced bologna and summer sausage | Whey protein isolate (WPI, pH 5.2) films | 0.5 to 1.0% p-aminobenzoic acid (PABA) and/or sorbic acid (SA) | L.monocytogenes, E. coli O157:H7, and S. enterica typhimurium (106 CFU/g) | 0.1 mL of inoculum spread onto both surfaces | 4°C, 21 days (d)
Slices placed in plates covered with edible film Stored in aerobiosis | WPI films with SA or PABA reduced L. monocytogenes, E. coli, and S. typhimurium populations by 3.4–4.1, 3.1–3.6, and 3.1–4.1 log CFU/g, respectively, on both products | [29] |
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| Hot dogs (beef 60%, pork 40%) | Whey protein isolate films (casings) | p-aminobenzoic acid (PABA) 1% | L. monocytogenes (103 CFU/g) | Immersion in L. monocytogenes culture for 1 min and dried in a safety cabinet | 4°C, 42 d
Vacuum-packaged samples | Growth inhibition for 42 d in refrigeration but no population reduction. Controls increased around 2.5 CFU/g | [30] |
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| Beef muscle slices | Milk protein films | Oregano essential oil (OR) 1.0% (w/v), Pimento essential oil (PI) 1.0% (w/v), or 1% OR-PI (1 : 1) | Escherichia coli O157:H7 or Pseudomonas spp. (103 CFU/cm2) | Spreading over meat surface Samples placed in plates, covered on either side with the corresponding film | 4°C, 7 d
Meat sterilized by radiation and then inoculated Samples in plates were hermetically sealed | Film with OR was the most effective against both bacteria
Reduction of 0.95 log of Pseudomonas spp. and 1.12 log reduction of E. coli O157:H7 | [31] |
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| Sterile beef muscle slices or ground beef | Palmitoylated alginate films Activated alginate beads | Covalently immobilized nisin (N) to activated alginate beads (AAB) (0–1000 IU/mL), or ground beef mixed with 0–1000 IU/mL of N | Staphylococcus aureus (104 CFU/g) | Inoculated using a sterile spoon and placed in sterile plates | 4°C, 14 d
Covered with immobilized nisin film or mixed with nisin solution | Reduction of 0.91 and 1.86 log CFU/cm2 on samples covered with film (500 or 1000 IU/mL, resp.) After 14 days: N solution (500 or 1000 IU/g) mixed with ground beef reduced to 2.2 and 2.81 log CFU/g, respectively; N (500 or 1000 IU/g) in AAB reduced to 1.77 and 1.93 log CFU/g, respectively | [28] |
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| Roast beef | Chitosan (CH, high or low molecular weight) coatings dissolved in lactic or acetic acid | Chitosan, lactic, or acetic acid (0.5 and 1%; w/v) | Listeria monocytogenes (106 CFU/g) | 1 mL culture onto 5 g cubed meat, air dried 10 min
Then dipped in chitosan for 30 s, dried for 1 h and placed into sterile Whirl-Pack bags | 4°C, 28 d
5 g cubed roast beef samples placed into sterile bags | Reduction of 1–3 log CFU/g for low molecular weight chitosan in acetic and lactic acids, respectively, after 28 d | [32] |
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| Frankfurters | Cellulose (produced by
G. xylinus)
films | Nisin (N), 625 and 2500 IU/mL | L. monocytogenes Scott A serotype 4b (106 CFU/mL) | Dipping in 0.85% saline sln. containing L. monocytogenes for 2 s | 4°C, 14 d
Samples wrapped in a single layer of film and vacuum-sealed for 2.5 s | Films containing 625 IU/mL N not significantly reduced L. monocytogenes populations. Films with 2500 IU/mL N decreased 2 log CFU/g compared to the control | [33] |
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| Pork loins | Gelidium corneum–gelatin (GCG) films | Grapefruit seed extract (GFSE, 0.08% w/v) or green tea extract (GTE, 2.80% w/v) | E. coli O157:H7 (NCTC12079) and L. monocytogenes (KCTC 3710) (105 CFU/g each one) | Spread with a sterile glass rod and allowed to drain for 10 min | 4°C, 10 d
Samples were packed in direct contact to films and stored in sterile polystyrene trays | Samples packed with the GCG film containing GFSE or GTE decreased population of E. coli O157:H7 and L. monocytogenes in 1 and 2 log CFU/g, respectively, compared to the control | [34] |
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| Ham | Cellulose acetate films | Pediocin (ALTA 2351)
(25% and 50%, w/v) | L. innocua (106 CFU/mL) and Salmonella sp. (106 CFU/mL) | Immersion in a 0.1% w/v peptone solution of
L. innocua or Salmonella sp. for 10 min | 12°C, 15 d
Samples sterilized under UV (5 min each side)
Films intercalated with ham slices packed in plastic bags and vacuum sealed | The 50% pediocin-film reduced L. innocua 2 log relative to the control. The 25% and 50% pediocin-films had similar performance on Salmonella sp. inhibition, both presenting 0.5 log reduction relative to the control | [35] |
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| Fresh ground beef patties | Soy protein films | Oregano (OR), thyme (TH), or OR-TH essential oils (5%) | E. coli O157:H7, Staphylococcus aureus, Pseudomonas aeruginosa, and Lactobacillus plantarum | No inoculation | 4°C, 12 d
Film applied to the upper and bottom surfaces of patties and vacuum packaged in plastic bags | Pseudomonas spp. in samples coated with TH and OR films decreased in 1.13 and 1.27 log CFU/g, respectively. Coliforms were reduced by 1.6, 1.9 and 2.0 log CFU/g with addition of OR, OR-TH, and TH, respectively | [36] |
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| Salami | Sodium caseinate (SC) films and coatings | Chitosan (CH) (2%) | Mesophilic and psychrotrophic aerobic bacteria and yeast and mold | No inoculation | 10°C, 5 d, 65% RH. Film added by immersion and as wrapper Immersed slices air dried at 30°C and 50% RH for 50 min
All food faces were contacted with wrapping film | CH and SC/CH films applied as both, coatings and wrappers, exerted a strong bactericidal action on 3 microbial populations analyzed, with reductions of 2 to 4.5 log CFU/g | [37] |
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| Ground beef patties | Zein films | Lysozyme (LY) (43 mg/g) and disodium Ethylene diamine tetra acetic acid (Na2EDTA, 19 mg/g) | Mesophilic microorganisms (TVC) and coliforms (TCC) | No inoculation | 4°C, 7 d
Films at both sides of each piece
Wrapped with stretch plastic film and with aluminum foil | After 5 and 7 d, TVC of patties with LY and Na2EDTA films were significantly lower (0.75–1.9 log CFU/g) than control films. After 5 d, TCC of patties with LY and Na2EDTA films were significantly lower than the control but after 7 d, no significant difference in TCC of patties was found | [38] |
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| Pork meat hamburgers | High molecular weight chitosan (1% w/v), acetic acid (1% w/v), lactic acid (1% w/v) films | Sunflower oil (1%) | Mesophilic bacteria, coliforms | No inoculation | 5°C, 8 d
Surface of both sides of the hamburgers coated with the films placed in PET trays | Reduction of 0.5–1 log for mesophilic microorganisms; 1 log CFU/g for coliforms | [39] |
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| Cooked ham and bologna | High methoxyl pectin + Apple, carrot or hibiscus puree films | Carvacrol (CV) or cinnamaldehyde (CM) (0.5%, 1.5%, and 3.0%, w/v) | L. monocytogenes (101M; serotype 4b) 106 CFU/mL | Dispersed on the surface as droplets. Inoculated samples dried under the biohood (30 min), flipped over, and inoculated on the other side Inoculated samples were dried again (30 min) and then surface wrapped with one of the test films | 4°C, 7 d
Samples were kept frozen and thawed before use. Sample wrapped in 2 pieces of circular films and parts of the films were not directly in contact with the meat surface | Films containing 3% CV showed 3 log reductions on ham at day 7. Bologna, films with 3% CV reduced 2 log CFU/g at day 7. Reductions with 1.5% CV were 0.5–1, 1–1.5, and 1-2 logs at day 0, 3, and 7, respectively. Films containing 3% CM, only 0.5–1.5 and 0.5–1.0 log CFU/g reductions were seen at day 7 on ham and bologna, respectively. Limited reduction (0.2-0.3 log CFU/g) was observed with 1.5% CM films | [40] |
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| Bacon | Red algae (RA) films | 1% w/v, grapefruit seed extract (GFSE) | Escherichia coli O157:H7 (106 CFU/g) and L. monocytogenes (107 CFU/g) | Spread separately on the surface of bacon with a sterile glass rod and allowed to rest for 30 min | 4°C, 15 d
Packed by wrapping | E. coli O157:H7 decreased 0.45 log CFU/g and L. monocytogenes decreased by 0.76 log CFU/g respect to the controls | [41] |
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| Pork sausages | Chitosan films | Green tea extract 20% (w/v) in the chitosan film-forming solution | Mesophilic bacteria, yeasts and molds, lactic acid bacteria (LAB), not inoculated | No inoculation | 4°C, 20 d
Sausages wrapped with films, packaged into a pouch of low density polyethylene coated with polyamide plastic bag and heat-sealed | On day 12, faster growth in control samples for total viable count and molds and yeast was found; no difference for LAB | [42] |
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| Cooked cured ham | Polylactic acid (PLA) films | Lauric arginate (LAE) (0% to 2.6%, w/w) | Listeria monocytogenes and Salmonella enterica serovar typhimurium (105 CFU/mL) | Inoculum of both L. monocytogenes and S. typhimurium onto surface of the sliced ham | 4°C, 7 d
Slices sterilized with UV on each side prior to inoculation Inoculated samples wrapped with LAE-coated PLA film and stored in closed plates | LAE-coated PLA film (2.6%) showed a significantly greater antibacterial activity, with L. monocytogenes and S.typhimurium levels reduced to <2 log CFU/film after 24 h exposure and remaining at this low level for the next 6 d | [43] |
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