New research on microbial reduction and sanitization with dry acidifier Dr. Cassie Jones Department of Grain Science and Industry Kansas State University
Background Food Safety Modernization Act requires control of biological hazards CGMPs, process controls, sanitation controls FDA Compliance Policy Guide Sec. 690.800 Zero tolerance for Salmonella in pet food 2
Reportable Foods Registry Reports for Animal Food 2009-2013 3
Reportable Foods Registry Reports for Animal Food 2009-2013 4
Control of Salmonella spp. CGMPs Process controls Point-in-time (extrusion); do not prevent cross-contamination Chemical additives; may prevent cross-contamination Acids and alkalis Formaldehyde Medium chain fatty acids Essential oils Sanitation Controls 5
Sodium bisulfate Manufactured by Jones-Hamilton, Co. Not the same as sodium metabisulfite, Na 2 S 2 O 5 Approved Uses (food, feed, technical grades) General purpose feed additive, AAFCO 1997 Added to pet food for urine acidification (prevent struvite) Added to soft treats for ph reduction Used in poultry feed as an acidifier 3-10 lb/ton for broilers, 3-6 lb/ton for turkeys 6
Sodium bisulfate Function Acidification lowers ph to prevent further growth Dissociation causes the free hydrogen to lower the ph NaHSO 4 Na + + H + + SO 4 - Desiccant draws water from bacteria cytoplasm 7
Hypotheses Functionality of SBS may reduce Salmonella contamination when: Applied as a coating to finished kibble Applied to animal food manufacturing surfaces 8
Impact of SBS coating on Salmonella in commercial cat foods 10 commercial foods (5 cat, dog) Kibble coated with SBS Cat: 0.0, 0.6, 0.8% Dog: 0.0, 0.2, 0.4% Coating = 2.2% spray-dried chicken liver + SBS or powdered silica Inoculated with dry Salmonella enterica d 0 Salmonella enumeration via BAM 9
Impact of SBS coating on Salmonella in commercial dog foods 10 commercial foods (5 cat, dog) Kibble coated with SBS Cat: 0.0, 0.6, 0.8% Dog: 0.0, 0.2, 0.4% Inoculated with dry Salmonella enterica d 0 Salmonella enumeration via BAM 10
Impact of SBS coating on Salmonella in uncoated dog foods Single formula high CP dog food 4 3 factorial Kibble sizes: S, M, L, XL SBS level: 0.0, 0.2, 0.4% Inoculated with dry Salmonella cocktail d 0 Salmonella enumeration via BAM 11
Impact of SBS coating on Salmonella in uncoated dog foods Single formula high CP dog food 4 3 factorial Kibble sizes: S, M, L, XL SBS level: 0.0, 0.2, 0.4% Inoculated with dry Salmonella cocktail d 0 Salmonella enumeration via BAM 12
Impact of SBS coating on palatability in dog foods Standard 2-bowl forced choice, commercial kennel in IL 20 beagles 2 days 400 g diet fed twice daily Bowl rotated daily to prevent side bias First Approach 13
Impact of SBS coating on palatability in dog foods Standard 2-bowl forced choice, commercial kennel in IL 20 beagles 2 days 400 g diet fed twice daily Bowl rotated daily to prevent side bias First Choice 14
Impact of SBS coating on palatability in dog foods Standard 2-bowl forced choice, commercial kennel in IL 20 beagles 2 days 400 g diet fed twice daily Bowl rotated daily to prevent side bias Total Consumption 15
Control of Salmonella spp. CGMPs Process controls Point-in-time (extrusion); do not prevent cross-contamination Chemical additives; may prevent cross-contamination Acids and alkalis Formaldehyde Medium chain fatty acids Essential oils Sanitation Controls 16
Control of Salmonella spp. Sanitation Controls Employee zoning Surface sanitization Most equipment is not designed to be clean-in-place Sanitizers cannot cause chemical hazards Introduction of water may increase overall a w 17
Sanitization of Salmonella on animal food manufacturing surfaces 5 Different Surfaces (25.8 cm 2 ) Plastic Polyethylene Tote Bag Rubber Stainless Steel Tire 18
Sanitization of Salmonella on animal food manufacturing surfaces 9 Treatments 1. Negative (not inoculated, no chemical treatment) 2. Positive (inoculated, no chemical treatment) 3. Ground corn (mechanical action) 4. Commercial formaldehyde (SalCURB, Kemin) 5. Commercial food-grade sanitizer (DrySan Duo, ECOLAB) 6. Medium chain fatty acids (Cochrane et al., 2015, 2016) 7. Commercial calcium propionate (SHIELD CA, Kemin) 8. Commercial dry acidulant (Sodium Bisulfate, Jones-Hamilton Co.) 9. Commercial benzoic acid (VevoVitall, DSM) 19
Sanitization of Salmonella on animal food manufacturing surfaces Surfaces inoculated with 1 ml liquid Salmonella Typhimurium Dried for 24 hours, 37 C 15 g treatment applied to surface Incubated 15 minutes, tapped to remove treatment Surface swabbed, placed in neutralizing broth, diluted, spread to TSA plates Positive Controls 20
Sanitization of Salmonella on plastic animal food manufacturing surfaces 21
Sanitization of Salmonella on polyethylene tote bags 22
Sanitization of Salmonella on rubber animal food manufacturing surfaces 23
Sanitization of Salmonella on stainless steel animal food manufacturing surfaces 24
Sanitization of Salmonella on tires 25
Sanitization of Salmonella on animal food manufacturing surfaces by SBS Surfaces inoculated with 1 ml liquid Salmonella Typhimurium Dried overnight, 37 C Treatment dusted on surface Incubated 15 minutes at 22 C and at least 15% relative humidity, tapped to remove treatment Surface placed in stomacher bag, 100 ml sterile water added, water diluted, spread to TSA plates, incubated 37 C for 24 hours 26 Salmonella, log 10 CFU/cm 2 7 6 5 4 3 2 1 0 Positive Controls 6.1 6.0 5.0 Stainless Plastic Rubber
Sanitization of Salmonella on stainless steel surfaces by SBS Surfaces inoculated with 1 ml liquid Salmonella Typhimurium Dried overnight, 37 C Treatment dusted on surface Incubated 15 minutes at 22 C and at least 15% relative humidity, tapped to remove treatment Surface placed in stomacher bag, 100 ml sterile water added, water diluted, spread to TSA plates, incubated 37 C for 24 hours 27 Salmonella, log 10 CFU/cm 2 6 5 4 3 2 1 0 Positive Control SBS Granular 5.0 n/d Negative Formalin SBS Powder 3.3 1.5
Sanitization of Salmonella on plastic surfaces by SBS Surfaces inoculated with 1 ml liquid Salmonella Typhimurium Dried overnight, 37 C Treatment dusted on surface Incubated 15 minutes at 22 C and at least 15% relative humidity, tapped to remove treatment Surface placed in stomacher bag, 100 ml sterile water added, water diluted, spread to TSA plates, incubated 37 C for 24 hours 28 Salmonella, log 10 CFU/cm 2 7 6 5 4 3 2 1 0 Positive Control SBS Granular 6.1 n/d Negative Formalin SBS Powder 4.2 n/d
Sanitization of Salmonella on rubber surfaces by SBS Surfaces inoculated with 1 ml liquid Salmonella Typhimurium Dried overnight, 37 C Treatment dusted on surface Incubated 15 minutes at 22 C and at least 15% relative humidity, tapped to remove treatment Surface placed in stomacher bag, 100 ml sterile water added, water diluted, spread to TSA plates, incubated 37 C for 24 hours 29 Salmonella, log 10 CFU/cm 2 7 6 5 4 3 2 1 0 Positive Control Negative Formalin SBS Granular SBS Powder 6.0 n/d n/d n/d
Summary Sodium bisulfate is an approved feed additive as an acidifier Reduces Salmonella contamination when applied as a coating in dry extruded dog and cat food Reduces Salmonella concentration on animal food manufacturing surfaces 30