Evaluating bacterial lethality of containerized food production

Abstract

Procedures and means for evaluating effectiveness of bacterial-lethality, following batch-processed containerized food production operations and aseptic-flow food-production operations as containerized in aseptic-containers, in preparing for non-refrigerated marketing are described. The evaluations significantly expedite determining whether thermally-processed containerized food-production is safe for non-refrigerated marketing. The presence or absence of live spore-forming bacteria is determined chemically free of extended storage requirements relying on a mechanical-failure indication of food-spoilage. Also, a biological-indication verification of microbial-biocidal status of the packaged food is made available. The invention determines whether rigid-sheet metal containers, and/or whether any of the new, and newly developing, non-refrigerated food packages, which largely utilize polymeric materials, for convenient microwave-oven heating of opened-packs, and soft polymeric pouch products, are safe for non-refrigerated marketing; and, such determinations are made substantially more concurrently with production-operations, than previously available.

1 . Process for determining effectiveness of timed elevated-temperature thermal-processing of in-line batch-processed containerized food production-operations including in-line aseptic flow-processing for aseptic-containerization production-operations, for evaluating whether safe for non-refrigerated marketing, comprising
 (A) providing sealed test-ampoules for evaluating bacterial-lethality of batch-processed food, by:
 (i) selecting spore-producing-bacteria, for such test ampoules of a type associated with spoilage of such food being batch-processed, 
 (ii) providing,
 (a) for fabricating such test-ampoules of selected configuration and internal capacities, 
 (b) for confining contents including such spore-producing bacteria plus liquid-state test constituents, and 
 (c) for remaining sealed during thermal-processing and following bacterial-lethality evaluation; 
 
   (B) confining such spore-producing food-spoilage bacteria and liquid-state test constituents within an individual test-ampoule of said test-ampoules;   (C) placing individual test-ampoules for monitoring thermal-processing, so as to enable   (D) correlating:
 (i) biocidal results on spore-producing bacteria as sealed within such individual test-ampoules for monitoring thermal-operations with 
 (ii) biocidal results achieved on such spore-producing bacteria associated with such foods for containerized production-operations. 
   
     
     
         2 . The invention of  claim 1 , further including
 (E) selecting test-ampoule contents to include, in addition to said spore-producing bacteria,
 (i) means for responding to chemical-change in confined constituents within each such individual test-ampoule for monitoring thermal-processing, by 
 (ii) providing for a visually-detectable indication as to whether any such bacteria survived such thermal-processing within such a test-ampoule. 
   
     
     
         3 . The invention of  claim 2 , in which
 (iii) pH detector/indicator means provide for exhibiting color-change in contents of such a test-ampoule by responding to surviving bacteria, if any.   
     
     
         4 . The invention of  claim 3 , further including
 (F) positioning such a test-ampoule in a limited-number of such containers for monitoring thermal-processing so as to identify a substantially-greater number of containers, which are free of test-ampoules; which   (G) experience substantially the same thermal processing as experienced by such positioned individual containers which include a test-ampoule; so as to enable:
 (i) evaluating bacterial-lethality by relying on test-constituents in such limited-number of containers with test-ampoules, positioned, for 
 (ii) determining whether such greater-number of remaining containers are safe for non-refrigerated marketing. 
   
     
     
         5 . The invention of  claim 4 , including
 (H) providing for biological-indication of microbial-status following an incubation period, subsequent to production-line operations, available by
 (i) establishing culturing conditions for each said individual test-ampoule designated for monitoring thermal-processing as strategically-locating during production-line thermal-processing, so as to 
 (ii) verify microbial-biocidal status of such substantially-greater number of containers experiencing substantially the same thermal-processing as such strategically-located containers containing test ampoules. 
   
     
     
         6 . The invention of  claim 5 , in which
 (I) means for verifying microbial-biocidal status of such designated containers with test-ampoules area, selected from the group consisting of
 (a) spectroscopic means for measuring hydrogen-ion activity, and 
 (b) non-evasive electrical measuring means for indicating hydrogen-ion activity. 
   
     
     
         7 . Non-rigid polymeric test-ampoule for use in evaluating bacterial-lethality effectiveness of elevated-temperature thermal-processing, on food-spoilage bacteria associated with batch-processed food production containerized in substantially non-rigid packaging, for determining whether safe for non-refrigerated marketing, comprising
 (A) selecting non-rigid polymeric sheet material for fabricating such test-ampoule, so as to be capable of:
 (i) establishing a desired capacity for selected constituents, 
 withstanding elevated-temperature thermal-processing as part of such batch-food containerized production operations, while 
 (iii) confining
 (a) selected food-spoilage spore-producing bacteria, in 
 (b) a liquid spore-culturing medium, containing 
 (c) pH responsive means, for 
 (d) detecting chemical change due to microbial-action of surviving live bacteria, if any, in said test-ampoule, and, in which 
 (e) such selected polymeric material, 
 (f) maintains visual clarity during such thermal-processing and subsequent evaluation of bacterial-lethality effectiveness. 
 
   
     
     
         8 . The invention of  claim 7 , in which
 (B) said selected spore-producing food-spoilage bacteria comprise  Clostridium botulinum,      (C) said pH responsive means is selected to respond to microbial-action of surviving bacteria, if any, by:
 (i) exhibiting color-change responsive microbial-action due to inadequacy of thermal-processing during such food production operations, so as to be 
 (ii) visually-observable after cool-down following completion of such food production operations, and, in which 
   (D) such liquid spore-culturing medium provides for biological-indication of microbial status, following exposure of said test-ampoule to bacterial incubation conditions.   
     
     
         9 . The invention of  claim 8 , in which
 (E) said spore-culturing medium, confined within said test ampoule, comprises:
 (i) Glucose 
 (ii) Tryptone 
 (iii) Soytone 
 (iv) Soluble Starch 
 (v) Yeast Extract, and 
 (vi) Casamino Acids; 
   (F) such pH responsive means comprises Bromcresol Purple.   
     
     
         10 . The invention of  claim 9 , in which said non-rigid polymeric sheet material is:
 (i) substantially transparent to electromagnetic energy-wavelengths in a visible light spectrum, and   (ii) non-reactive chemically with contents of said test-ampoule, during
 (a) batch-food production operations, 
 (b) testing thereof, and 
 (c) during storage prior to usage at less 
   than spore-culturing condition temperature.   
     
     
         11 . The invention of  claim 10 , in which
 such polymeric sheet material is selected from the group consisting of:   
       
         
           
                 
                 
                 
                 
                 
               
                     
                     
                 
                     
                   (i)  
                   Polypropylene 
                   (iv)  
                   Polysulphone 
                 
                     
                   (ii)  
                   Polymethylpentene 
                   (v)  
                   Nylon, and 
                 
                     
                   (iii)  
                   Polyvinyl Chloride 
                   (vi)  
                   combinations thereof. 
                 
                     
                     
                 
             
                
               
               
                
                
                
                
               
            
           
         
       
     
     
         12 . Apparatus for evaluating containerized batch-food thermal-processing production operations, comprising
 (A) individual test-ampoules for monitoring microbial-biocidal results of such thermal-processing, which are
 (i) fabricated to withstand selected elevated-temperature thermal-processing during selected containerized batch-food production operations, 
 (ii) each individual test ampoule of said test-ampoules, including:
 (a) spore-growth nutrient medium, and 
 (b) food-spoilage bacteria, which are subject to destruction in response to intended thermal-processing during such production operations, and 
 
   (B) means for detecting change in acidity of such nutrient medium within each said individual test-ampoule.   
     
     
         13 . The invention of  claim 12 , including
 C) pH means for exhibiting a color-change if any bacterial cell, or germinated bacteria spore survives such thermal-processing.   
     
     
         14 . The invention of  claim 13 , further including
 (D) means for subjecting such test-ampoules, experiencing microbial-biocidal results of such thermal-processing, to incubating conditions following such thermal-processing, for providing   (E) a biological-indication of microbial-biocidal status of such test-ampoules, by
 (i) measuring hydrogen-ion concentration within such test-ampoules from containers, as strategically-positioned in-line, for 
 (ii) identifying a substantially greater number of containers experiencing such thermal-processing, so as to be capable of 
 (iii) indicating results of such elevated-temperature thermal-processing production operations in such greater number of containers, as identified by such selectively-positioned containers for monitoring thermal-processing, so as to determine whether 
 (iv) such greater number of containers are safe for non-refrigerated marketing. 
   
     
     
         15 . Process for protecting food quality during containerized batch-processed containerized food production operations providing for non-refrigerated marketing, comprising
 (A) predetermining pH value of foods selected for such batch-processed containerized food production operations;   (B) selecting minimal microbial-biocidal thermal-processing as estimated to be required during such food production operations, based substantially on such predetermined pH value, so as to enable minimizing thermal-processing;   (C) selecting and confining food-spoilage bacteria internally of test-ampoules, for responding to such estimated thermal-processing, for   (D) correlating microbial-biocidal action, on such selected bacteria as confined within such test-ampoules, with that required, during containerized-food production thermal-processing, for safe non-refrigerated marketing.   
     
     
         16 . The invention of  claim 15 , including
 (E) locating such test-ampoules as selected for responsively-correlating microbial-biocidal action, within
 (i) containers for monitoring thermal-processing, as positioned in-line during such production operations, 
 (ii) identifying a substantially greater number of in-line containers, so as to enable 
 (iii) at least a pair of test ampoules for monitoring thermal-processing, are positioned in-line during such production operations, so as to locationally-identify such substantially greater number of in-line containers experiencing substantially the same thermal-processing. 
   
     
     
         17 . The invention of  claim 16 , including
 (F) determining whether such correlated thermal-processing has been effective, so as to enable safe non-refrigerated distribution of such greater-number of containers, as subjected to such food production operations;   
       by evaluating whether:
 (G) chemical-change in acidity level has occurred within such test ampoules for monitoring thermal-processing by selecting from the group consisting of
 (a) visually-observing color-change pH response to acidity level following such production-operations, 
 (b) biological-indication of acidity-level response to continuing microbial-action, following such production operations, and 
 (c) combination of (a) and (b).