Classifications

• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
  • A23L3/00—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs
  • A23L3/34—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs by treatment with chemicals
  • A23L3/3454—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs by treatment with chemicals in the form of liquids or solids
  • A23L3/3463—Organic compounds; Microorganisms; Enzymes
  • A23L3/34635—Antibiotics
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
  • A23L3/00—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs
  • A23L3/015—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs by treatment with pressure variation, shock, acceleration or shear stress or cavitation
  • A23L3/0155—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs by treatment with pressure variation, shock, acceleration or shear stress or cavitation using sub- or super-atmospheric pressures, or pressure variations transmitted by a liquid or gas
• • A—HUMAN NECESSITIES
  • A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
  • A23L—FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BY SUBCLASSES A21D OR A23B-A23J; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OF NUTRITIVE QUALITIES, PHYSICAL TREATMENT; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL
  • A23L3/00—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs
  • A23L3/34—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs by treatment with chemicals
  • A23L3/3454—Preservation of foods or foodstuffs, in general, e.g. pasteurising, sterilising, specially adapted for foods or foodstuffs by treatment with chemicals in the form of liquids or solids
  • A23L3/3463—Organic compounds; Microorganisms; Enzymes
  • A23L3/3571—Microorganisms; Enzymes
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L2/00—Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor
  • A61L2/02—Methods or apparatus for disinfecting or sterilising materials or objects other than foodstuffs or contact lenses; Accessories therefor using physical phenomena

Definitions

• the invention relates to stabilisation of products which are vulnerable to spoilage or poisoning by microbial spores, especially ambient stable and extended chill shelf life products, in particular food products, and a process for the preparation thereof.
• a problem with edible products is that often they are susceptible to spore outgrowth on storage and hence need to undergo a preservation system to extend their shelf life.
• Typical preservation systems are;
• Both products produced using methods (i) and (ii) may have a high water activity (Aw of above 0.93) ; or
• the present invention relates to a process for producing a shelf stable product comprising
• a membrane destructive agent is added to the product prior to step (a) or step (b) or immediately after step (b) .
• shelf-stable product is meant a product that has extended shelf-life either under ambient storage conditions (stable for > 3 months) or under chill conditions (stable for > 10 days) .
• vegetative cells By vegetative cells is meant both germinated spores and non-spore forming micro-organisms.
• the membrane destructive agent is added prior to step (a) :
• step (a) the pressure conditions at moderate temperatures for 1 minute to 10 hours will allow the germination of the spores to occur. Preferably this is done in the presence of a membrane destructive agent. Surprisingly, it has been found that the combined application of the pressure conditions and the membrane destructive agent leads to a very high degree o spores to be germinated and a surprisingly low level of super-dormant spores.
• step (b) the vegetative cells are inactivated by, for example, heat treatment (conventional pasteurisation) , repetitive heat treatments, pressure treatment, repetitive pressure treatment, or by a combination thereof.
• This step will not only kill the non-spore forming micro-organisms, but will also kill the germinated spores. The net result is that spores are very effectively removed and no active micro-organisms are formed from the spores.
• step (a) are 10-1000 Mega-Pascal at a temperature of less than or equal to 60°C for a time between 1 minute to 10 hours.
• the pressure in step (a) is from 50 to 400 Megapascal, more preferred 50 to 300 Megapascal, most preferred 50 to 250 Megapascal.
• Pressure may be generated by any method for high pressure generation, for example liquid pressure may be applied whereby the product is liquid in itself or is emersed in water after which the pressure of the water is raised.
• High pressure technology in general and its potential use is for example described by R.G. Earnshaw (Food Technology International Europe '92 pages 85-88) .
• the temperature is preferably from 10 to 60°C, more preferred 20 to 60°C, most preferred 35 to 60°C?
• the time for step (a) is preferably from 10 minutes to 8 hours, more preferred 20 minutes to 5 hours, most preferred 20 minutes to 4 hours.
• cell membrane destructive agent has the meaning as known in the art: ie. any agent capable of affecting microbial membranes for example, lantibiotics, pseudorandom peptides, magainins, attacins, cecropins, defensin, eugenol, allecin, subtilin, Pep 5, epidermin, cinnamycin, Ro09-0918, duramycin and ancovenin.
• the amount of cell membrane destructive agent is preferably from 10 to 1000 ppm, more preferred 15 to 300 ppm, most preferred 25 to 150 ppm.
• lantibiotics such as described in EP 427 912.
• Members of this group include nisin, and pediocin.
• nisin is particularly preferred.
• Another class of membrane destructive agents are pseudo ⁇ random peptides.
• the term 'pseudo-random' will be used to refer to both completely random peptides and to those in which no steps have been taken to inhibit or restrict peptide growth to single step elongation of the peptide chains so as to produce an ordered sequence of residues.
• These peptides having far less structure than those found in nature, are known and have found applications as drug carriers or as reagents in immunological assay techniques.
• the peptide comprises a co-polymer of at least one amino acid having an isoelectric point above 7 and at least one amino acid having a bulky functional group.
• bulky groups are those having a total of five or more carbons and heteroatoms. These include the aromatic groups derived from toluyl rings (as in phenylalanine and tyrosine) and indoles (as in tryptophan) , as well as sufficiently long side chains such as the guanidino group of arginine, and the amino group of lysine.
• amino acid having an isoelectric point above 7 is selected from the group comprising arginine, lysine, histidine and mixtures thereof.
• the amino acid having an aromatic or other bulky functional group is selected from the group comprising arginine, tryptophan, tyrosine, phenylalanine and mixtures thereof.
• arginine, and ornithine have a sufficiently high isoelectric point and sufficiently bulky functional group in the side chain that poly-arginine and poly-ornithine are effective peptides.
• Particularly preferred peptides are those which comprise homopolymers of arginine and copolymers of lysine and phenylalanine, arginine and tryptophan and/or lysine and tryptophan. Mixed systems are also envisaged.
• the molar ratio of amino acids of the two types is preferably in the range 10:1-1:10, more preferably 5:1-1:2 with an equal or predominant molar quantity of the basic amino acid being preferred.
• amino acid residues can be present in the peptide, including non-standard amino acids such as ornithine, which is not an essential amino acid but does have an isoelectric point close to 10.
• the membrane destructive agent is selected from lantibiotics, pseudo-random synthetic peptides and mixtures thereof.
• the membrane destructive agent is nisin.
• the inactivation of the vegetative cells (step (b) ) can be carried out in any suitable way, for example by heat treatment to a temperature of 60 to 100°C for 1 to 100 minutes. Particularly preferred, however is that the inactivation is a high pressure sterilisation at a pressure of 300 - 1500 Megapascal, a temperature of 60°C or below and a time of 1 minute to 10 hours. If high pressure conditions are used in step (a) and in step (b) this will provide a surprisingly good product quality.
• the pressure during step (b) is at least 50 megapascal higher than the pressure during step (a) , more preferred more than 100 Megapascal higher e.g. 100 to 400 megapascal higher than the pressure in step (a) .
• the pressure in step (b) is between 350 and 500 Megapascal.
• step (b) is preferably from 5 to 50°C, more preferred 10 to 45°C, most preferred 15 to 40°C, for example ambient temperature.
• the time for high pressure inactivation in step (b) is preferably from 5 minutes to 8 hours, more preferred 10 minutes to 5 hours, most preferred 10 minutes to 4 hours.
• step (a) and (b) may be repeated for even further reducing the number of spores in the products.
• the product may be subjected to 2 to 10 preservation cycles as described above.
• the number of cycles is from 2 to 4.
• the preservation process of the invention may advantageously be applied to all products which tend to suffer from problems with spores.
• suitable products are food products, personal products and detergency products.
• the preservation process is applied to products, having a pH of more than 4.6, more preferred more than 4.6 and less than 10, most preferred more than 4.7 and less than 8.
• the water-activity a w of the food is more than 0.93, more preferred a w is from 0.96 to 1.00, most preferred 0.97 to 1.00.
• the process of the invention allows for the production of shelf stable products whereby only moderate temperatures are applied, the process of the invention is especially suitable for products to which a high temperature is detrimental to its quality e.g. products which are unstable or undergo undesired structural changes or form off-flavours when heated at temperatures normally used in preservation.
• Examples of cosmetic products which may be subjected to the process of the invention are creams, lotions, tonics, toothpaste, lipstick, gels, shampoo and other hair products.
• detergent products are liquid systems like liquid fabric washing detergents, household cleaners, abrasives, fabric conditioners and (semi-) solid detergents e.g. pastes and soap bars.
• the process is used to provide shelf stable foodstuffs.
• suitable food products are spreads, in particular zero or extremely low fat spreads, dressings, dairy and non-dairy creams, toppings, processed cheese, pates, semi-hard cheese, sauces, sweet spreads, margarines, ice-cream, meat and fish products, bavarois, bakery and dough products, vegetables, fruit, soups, dairy products, beverages.
• this process may be used to provide ambient stable sauces, soups and dressings.
• the edible products are preferably filled into a suitable package for further use. If the filling takes place before steps (a) and (b) it is not necessary to use aseptic filling since the package will be sterilised during steps (a) and (b) .
• Bacillus subtilis was made in BHI at 30°C. Appropriate aliquots were streaked on agar plates (plate count Agar (Difco) ) supplemented with 0.04 mg/L MgCl 2 . The agar was incubated at 30°C for 3 to 5 days. Well sporulated cultures (>30% spores) were harvested by washing once in sterile distilled water.
• a spore concentration of from 10 6 to 10 7 /ml in 5ml distilled water was used.
• the spores were subjected to a high pressure treatment of 200 mPa at 35°C for 180 min, followed by pasteurisation at 85°C for 5 min.
• a number or different concentrations (0-100 ppm) of nisin were added prior to high pressure treatment.
• the spores were disseminated into agar and incubated for 5 days at 30°C before counting. Results are expressed as a log reduction factor.
• Example 1 was repeated except a number of different concentrations (0-200 ppm) of lysozyme were added prior to high pressure treatment instead of nisin. Results given in Table 2 are expressed as a log reduction factor.
• Clostridium botulinum type A strains ZK3, 62A, VII, type B strains 2345, bolus alba, 6 were used.
• a cocktail was made by mixing equal amounts of the spores together. Table 1
• the entire culture was inoculated into 1000 ml TPGS. This
• TPGS was then poured over the agar phase.
• the biphasic culture was incubated anaerobically for 5 to 7 days at 30°C.
• Meat Extract (Liebig) 1.67% bactopeptone (Difco) 1% tryptone (Difco) 1% gelatin (Gelatine Delft) 1% agar 2%
• the spore suspension was washed 3 times with distilled water by repeated centrifugation at about 5°C at 12000g for 10 min each time.
• the spores were then treated in an ultrasonic bath after washing to ensure loose spores.
• the treated suspension was heated for 10 min at 80°C to ensure elimination of botulinu toxin and/or vegetative cells and enumerated.
• Sporulation was carried out as described for proteolytic C.botulinum except that the treated suspension was heated for 30 min at 60°C to ensure elimination of botulinum toxin and/or vegetative cells before enumeration.
• 35 ppm nisin or 300 ppm Pediocin were added either prior to high pressure treatment (200 MPa at 45°C for 180 min) , prior to pasteurisation (protocol (i) - 85°C for 5 min,- protocol
• the C.botulinum was inoculated into CMM (cooked meat medium, Difco) to a final concentration of 10 7 /ml for the high pressure treatment and pasteurisation treatment . Recovery was carried out in Tryticase peptone glucose (TPG) (to enumerate C.botulinum) .
• TPG Tryticase peptone glucose
• the TPG agar plates were incubated anaerobically for 5 days at 30°C. Results, expressed as a log reduction factor are shown in Table 3.
• C.botulinum cocktail was prepared as detailed in Example 2.
• the final spore concentration was 10 7 /ml.
• Nisaplin was added to the cheese at a level of 0.05% by weight
• the cheese was subjected to a number of different pressure treatments for 180 min as detailed in Table 4, followed by a pasteurisation treatment of 80°C for 10 minutes.
• a C.botulinum cocktail was prepared as detailed in Example 2.
• B.subtilis spores were prepared as for Example 1.
• a spore concentration of from 10 6 to 10 7 /ml in 5ml distilled water was used.
• Nisin at 35 ppm concentration was added prior to pressure treatment and/or pasteurisation treatment.
• the pressure treatment was 200MPa, at 35°C for 180 min.
• the pasteurisation treatment was 80°C for 5 min.
• B.subtilis spores were prepared as for Example 1.
• a spore concentration of from 10 6 to 10 7 /ml in 5 ml distilled water was used.
• the spores were subjected to a high pressure treatment of 60MPa at 35°C for 30 min followed by either
• step (a) 35 ppm nisin was added prior to high pressure treatment. After treatment the spores were disseminated into agar and incubated for 5 days at 30°C before counting. Results are expressed as a log reduction factor and are shown in Table 8.

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• Life Sciences & Earth Sciences (AREA)
• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Food Science & Technology (AREA)
• Microbiology (AREA)
• Polymers & Plastics (AREA)
• Nutrition Science (AREA)
• Engineering & Computer Science (AREA)
• General Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Epidemiology (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Food Preservation Except Freezing, Refrigeration, And Drying (AREA)
• Peptides Or Proteins (AREA)
• Vending Machines For Individual Products (AREA)

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• 1994
  • 1994-08-30 CA CA002172244A patent/CA2172244A1/en not_active Abandoned
  • 1994-08-30 AU AU76148/94A patent/AU7614894A/en not_active Abandoned
  • 1994-08-30 SK SK382-96A patent/SK38296A3/sk unknown
  • 1994-08-30 HU HU9600718A patent/HUT74962A/hu unknown
  • 1994-08-30 JP JP7509522A patent/JPH09502874A/ja active Pending
  • 1994-08-30 WO PCT/EP1994/002891 patent/WO1995008275A1/en not_active Application Discontinuation
  • 1994-08-30 CN CN94194171A patent/CN1135165A/zh active Pending
  • 1994-08-30 CZ CZ96860A patent/CZ86096A3/cs unknown
  • 1994-08-30 PL PL94313616A patent/PL313616A1/xx unknown
  • 1994-08-30 EP EP94926227A patent/EP0793424A1/en not_active Withdrawn
  • 1994-09-05 ZA ZA946804A patent/ZA946804B/xx unknown
  • 1994-11-04 TW TW083110213A patent/TW302272B/zh active

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