Methods For Reducing Viscosity And Delaying Onset Of Cold Gelation Of High Solids Concentrated Milk Products

Abstract

Methods are provided for treating high solids concentrated milk products to delay gelation of the concentrated milk products by minimizing the rate at which the viscosity of the concentrates increases during cold storage. By another approach, the methods described herein are effective to substantially reduce the viscosity of the concentrated milk products. The methods described herein advantageously increase the length of time the high solids milk concentrates remain fluid and pumpable during refrigerated shelf-life. The high solids concentrated milk products treated with the methods provided herein include about 33 to about 43 percent total solids. By one approach, the high solids concentrated milk products have a pH of about 4.6 to about 6.7, and include salt at about 0.25 to about 6 percent by weight of the concentrate.

1 - 16 . (canceled) 
     
     
         17 . A method for slowing the rate of age gelation of a high solids milk concentrate, the method comprising:
 heating a concentrated dairy liquid at a temperature of about 140° F. to about 170° F. for a time effective to achieve an at least 2 log reduction in vegetative pathogenic and spoilage organisms, the concentrated dairy liquid having a solids content of about 33 to about 43 percent, a pH of about 4.6 to about 6.7, and including about 0.25 to about 6 added salt; and   cooling the concentrated dairy liquid to 55° F. or less,   the heating and cooling steps being effective to provide an initial viscosity of the concentrated dairy liquid of less than 20 Pa·s which remains below 20 Pa·s for at least 24 hours at 45° F. or less.   
     
     
         18 . The method according to  claim 17 , wherein the heating step is conducted for a time effective to achieve an at least 3 log reduction in vegetative pathogenic and spoilage organisms. 
     
     
         19 . The method according to  claim 17 , wherein the concentrated dairy liquid has a solids content of about 33 to about 35 percent. 
     
     
         20 . The method according to  claim 17 , wherein the heating step is carried out at a temperature of about 140° F. to about 170° F. when the concentrated dairy liquid has a solids content of about 36 to about 38 percent. 
     
     
         21 . The method according to  claim 17 , wherein the heating step is carried out at a temperature of about 140° F. to about 165° F. when the concentrated dairy liquid has a solids content of about 39 to about 41 percent. 
     
     
         22 . The method according to  claim 17 , wherein the heating step is carried out at a temperature of about 140° F. to about 161° F. when the concentrated dairy liquid has a solids content of about 42 to about 43 percent. 
     
     
         23 . The method according to  claim 17 , the method further comprising tempering the concentrated dairy liquid at a temperature of about 68° F. to about 130° F. and cooling the tempered concentrated dairy liquid to about 55° F. or less when the concentrated dairy liquid has a viscosity of at least about 20 Pa·s, the tempering effective to provide a tempered viscosity after cooling that is less than about 20 Pa·s. 
     
     
         24 . The method according to  claim 23 , wherein the tempering step is effective to provide a tempered viscosity after cooling that is less than about 15 Pa·s. 
     
     
         25 . The method according to  claim 23 , wherein the tempering step is effective to provide a tempered viscosity after cooling that is less than about 10 Pa·s. 
     
     
         26 . The method according to  claim 23 , wherein tempering reduces the tempered viscosity of the concentrated liquid to within about 45 percent of the initial viscosity. 
     
     
         27 . The method according to  claim 23 , wherein tempering reduces the tempered viscosity of the concentrated dairy liquid to less than the initial viscosity. 
     
     
         28 - 34 . (canceled) 
     
     
         35 . A method for delaying age gelation of a high solids milk concentrate by slowing the rate of viscosity increase, the method comprising:
 concentrating a dairy liquid to a solids content of about 33 to about 43 percent;   treating the concentrated dairy liquid with about 0.25 to about 6 percent salt and acidifying the concentrate to provide a pH of about 4.6 to about 6.7;   heating the treated, concentrated dairy liquid at about 140° F. to about 170° F. for a time effective to achieve an at least 2 log reduction in vegetative pathogenic and spoilage organisms; and   cooling the concentrated dairy liquid to about 55° F. or less,   the heating and cooling steps being effective to provide an initial viscosity of the concentrated dairy liquid of less than 20 Pa·s which remains below 20 Pa·s for at least 24 hours at 45° F. or less.   
     
     
         36 . The method according to  claim 35 , wherein the concentrated dairy liquid has a solids content of about 33 to about 35 percent. 
     
     
         37 . The method according to  claim 35 , wherein the heating step is carried out at a temperature of about 140° F. to about 170° F. when the concentrated dairy liquid has a solids content of about 36 to about 38 percent. 
     
     
         38 . The method according to  claim 35 , wherein the heating step is carried out at a temperature of about 140° F. to about 165° F. when the concentrated dairy liquid has a solids content of about 39 to about 41 percent. 
     
     
         39 . The method according to  claim 35 , wherein the heating step is carried out at a temperature of about 140° F. to about 161° F. when the concentrated dairy liquid has a solids content of about 42 to about 43 percent. 
     
     
         40 . The method according to  claim 35 , wherein the dairy liquid is concentrated by ultrafiltration, microfiltration, diafiltration, or a combination thereof. 
     
     
         41 . The method according to  claim 35 , wherein the dairy liquid is selected from the group consisting of whole milk, reduced fat milk, skim milk, and combinations thereof. 
     
     
         42 - 48 . (canceled) 
     
     
         49 . A method for reducing the viscosity of a high solids milk concentrate, the method comprising:
 treating a dairy liquid with about 0.25 to about 6 percent salt and acidifying the dairy liquid to provide a pH of about 4.6 to about 6.7;   concentrating the treated dairy liquid to a solids content of about 33 to about 43 percent;   adding additional salt to the concentrated dairy liquid to bring the total amount of salt in the concentrated dairy liquid to about 0.25 to about 6 percent salt;   heating the treated, concentrated dairy liquid at about 140° F. to about 170° F. for a time effective to provide at least a 2 log reduction of vegetative pathogenic and spoilage organisms; and   cooling the concentrated dairy liquid to about 55° F. or less,   the heating and cooling steps being effective to provide an initial viscosity of the concentrated dairy liquid of less than 20 Pa·s which remains below 20 Pa·s for at least 24 hours at 45° F. or less.   
     
     
         50 . The method according to  claim 49 , wherein the concentrated dairy liquid has a solids content of about 33 to about 35 percent. 
     
     
         51 . The method according to  claim 49 , wherein the heating step is carried out at a temperature of about 140° F. to about 170° F. when the concentrated dairy liquid has a solids content of about 36 to about 38 percent. 
     
     
         52 . The method according to  claim 49 , wherein the heating step is carried out at a temperature of about 140° F. to about 165° F. when the concentrated dairy liquid has a solids content of about 39 to about 41 percent. 
     
     
         53 . The method according to  claim 49 , wherein the heating step is carried out at a temperature of about 140° F. to about 161° F. when the concentrated dairy liquid has a solids content of about 42 to about 43 percent. 
     
     
         54 . The method according to  claim 49 , wherein the dairy liquid is concentrated by ultrafiltration, microfiltration, diafiltration, or a combination thereof. 
     
     
         55 . The method according to  claim 49 , wherein the dairy liquid is selected from the group consisting of whole milk, reduced fat milk, skim milk, and combinations thereof.