TIPS FOR HEAT-TREATING COLOSTRUM
Successfully heat-treating colostrum requires routine attention to detail, advises University of Minnesota researcher Sandra Godden. Among her suggestions:
1. Do not attempt to heat-treat fermented (soured) colostrum or you may find yourself with a batch of pudding. Fresh colostrums should be heat-treated within two hours of harvest from the cow, or refrigerated immediately and then heat-treated within one to two days of collection.
2. Regularly monitor the time and temperature of the batch-heating process. Processing for less than 60 minutes will result in substandard bacterial kill, while temperatures higher than 61°C/142°F will start to cause damage to the vital immunoglobulin (IgG). The system must be able to precisely control the temperature in both the water jacket and colostrums to avoid over-ride in temperature above these limits. Temperature over-ride may result in reduced colostrum IgG and/or increased viscosity, possibly to the point of producing a gelatin-style colostrum in high-total-solids product.
3. Colostrum should be agitated during the heating-up, holding and cooling-down phases of the heat-treatment procedure, to ensure even treatment of all colostrum and to avoid overheating/IgG denaturation.
4. Culture raw and heat-treated colostrum at least once a month to measure the benefit of the heat-treating process. Goal: total plate count of heat treated colostrum of less than 20,000 cfu/mL.
5. Establish effective cleaning protocols for heat-treating equipment, colostrum storage, and colostrum feeding equipment. At Jon-De Farms, Inc., Baldwin, Wis., they recently have started using Perfect Udder receptacle bags (DairyTech, Inc., Windsor, Colo.) for storing and feeding heat-treated colostrum. Calf manager Sarah Kreft says the system helps preserve colostrum quality and dramatically reduces colostrum-handling errors.
6. Immediately cool down heat-treated colostrum in the pasteurizer and then either refrigerate or freeze. Heat-treated colostrums that is allowed to sit out unrefrigerated can quickly re-grow bacteria to pre-treatment levels or higher.
7. Routinely monitor disease incidence and passive transfer rates in calves. Goal: 90 percent of calves tested between one and seven days of age should have a serum IgG concentration of at least 10.0 g/L, and a serum TP value of at least 5.0 gm/dL.