Porphyrin containing lactic acid bacterial cells and use thereof

Abstract

Culturally modified lactic acid bacterial cells containing a porphyrin compound and their use in a novel method of reducing the oxygen content in a food and feed product or starting material is provided and means of improving the shelf life and/or quality of such products by using the culturally modified bacterial cells. Such culturally modified cells are useful in the manufacturing of a food and a feed product and for the manufacturing of metabolites produced by modified cells.

1 . A culturally modified lactic acid bacterial cell that has, relative to the cell from which it is derived, an increased content of a porphyrin compound.  
     
     
         2 . A cell according to    claim 1    that contains at least 0.1 ppm on a dry matter basis of a porphyrin compound.  
     
     
         3 . A cell according to    claim 1    that contains a detectable amount of a cytochrome.  
     
     
         4 . A cell according to    claim 3    that contains at least 0.1 ppm on a dry matter basis of a cytochrome.  
     
     
         5 . A cell according to    claim 4    that contains at least 0.1 ppm on a dry matter basis of cytochrome d  
     
     
         6 . A cell according to    claim 1    which is of a bacterial species selected from the group consisting of Lactococcus spp., Lactobacillus spp., Leuconostoc spp., Pediococcus spp., Streptococcus spp., Propionibacterium spp., Bifidobacterium spp. and Oenococcus spp.  
     
     
         7 . A cell according to    claim 6    where the bacterial species is of  Lactococcus lactis , including  Lactococcus lactis  strain CHCC373 deposited under the accession number DSM12015.  
     
     
         8 . A cell according to    claim 1    which, when it in the form of a cell suspension is inoculated in a concentration of 10 7  cells/ml into low pasteurised skimmed milk having 8 ppm of dissolved oxygen and leaving the milk to stand for about two hours at a temperature of about 30° C. consumes at least 25% of the oxygen.  
     
     
         9 . A cell according to    claim 8    where the cell consumes at least 50% of the dissolved oxygen.  
     
     
         10 . A cell according to    claim 1   , which, relative to the cell from which it is derived, has a decreased NOX activity and/or a decreased LDH activity.  
     
     
         11 . A cell according to    claim 10    that has a NOX activity which is decreased by at least 10%.  
     
     
         12 . A cell according to    claim 10    that has a LDH activity which is decreased by at least 10%.  
     
     
         13 . A starter culture composition comprising the culturally modified lactic acid bacterial cell of any of claims  1 - 12 .  
     
     
         14 . A composition according to    claim 13    where the composition is in the form of a frozen, liquid or freeze-dried composition.  
     
     
         15 . A composition according to    claim 13    containing an amount of viable culturally modified lactic acid bacterial cells which is in the range of 10 4  to 10 12  CFU per g.  
     
     
         16 . A composition according to    claim 13    that comprises cells of two or more different lactic acid bacterial strains.  
     
     
         17 . A composition according to    claim 13    which further comprises at least one component enhancing the viability of the bacterial cell during storage, including a bacterial nutrient and/or a cryoprotectant.  
     
     
         18 . A method of reducing the oxygen content in a food or feed product or in a food or feed product starting material comprising adding to the product or to the starting material an effective amount of the culturally modified lactic acid bacterial cells according to any of claims  1 - 12  or the starter culture composition according to any of claims  13 - 17 .  
     
     
         19 . A method according to    claim 18    wherein the amount of modified cell is in the range of 10 4  to 10 12  CFU per g.  
     
     
         20 . A method according to    claim 18    wherein the starting material for the food product is selected from the group consisting of milk, a vegetable material, a meat product, a fruit juice, a must, a wine, a dough and a batter.  
     
     
         21 . A method of improving the shelf life and/or the quality of an edible product comprising adding to the product an effective amount of the culturally modified lactic acid bacterial cells according to any of claims  1 - 12  or the starter culture composition according to any of claims  13 - 17 .  
     
     
         22 . A method of preparing a fermented food or feed product, comprising adding an effective amount of the culturally modified lactic acid bacterial cell according to any of claims  1 - 12  or the composition of any of claims  13 - 17  to a food or feed product starting material, wherein the cell or the composition is capable of fermenting said starting material to obtain the fermented food or feed.  
     
     
         23 . A method according to    claim 22    wherein the starting material for the food product is selected from the group consisting of milk, a vegetable material, a meat product, a fruit juice, a must, a wine, a dough and a batter.  
     
     
         24 . A method according to    claim 23    wherein the resulting fermented food product is a dairy product including a product selected from the group consisting of cheese and buttermilk.  
     
     
         25 . Use of the lactic acid bacterial cell of any of claims  1 - 12  or the composition of any of claims  13 - 17  for the production of a metabolite produced by the cell or the composition or by a non-modified cell co-cultivated therewith.  
     
     
         26 . Use according to    claim 25    where the metabolite is selected from the group consisting of lactic acid, acetaldehyde, α-acetolactate, acetoin, acetate, ethanol, diacetyl and 2,3-butylene glycol.  
     
     
         27 . Use of the lactic acid bacterial cell of any of claims  1 - 12  or the composition of any of claims  13 - 17  for the production of a bacteriocin.  
     
     
         28 . Use according to    claim 27    where the bacteriocin is selected from the group consisting of nisin, reuterin and pediocin.