Hygienic Sampling Practices Are Vital to Protecting Dairy Product Quality and Safety
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Hygienic Sampling Practices Are Vital to Protecting Dairy Product Quality and Safety

Milk collected from the udders of healthy cows is almost sterile but microbial contaminants are introduced during milking, storage, processing, and distribution. Cleaning and sanitation failures allow contaminating organisms to accumulate in dairy processing equipment, potentially leading to the development of biofilms that can become a significant and persistent source of contamination. On the farm and…

Effective Micro Program: Understanding the Microbiological Tests (Part 4)
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Effective Micro Program: Understanding the Microbiological Tests (Part 4)

Throughout this series on dairy microbiological testing, we have discussed the types of micro tests that can be used to enumerate the classifications of bacteria we are concerned with in fluid milk processing. The first two articles discussed Gram-negative bacteria in raw milk and the effects of Gram-positive heat resistant thermoduric/psychrotrophic spore formers (HRSF) on…

Micro Testing for Post-pasteurization Contamination (Part 3)
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Micro Testing for Post-pasteurization Contamination (Part 3)

The first article in this series, Raw Milk Dairy Micro Testing, focused on Gram-negative bacteria in raw milk with the Preliminary Incubation (PI) Count and Fresh Standard Plate Count (SPC) tests. The second article, The Effects of Gram-positive HRSF Bacteria on Fluid Milk Shelf Life, discussed another classification of bacteria that was not known as…

Honoring Four Decades of Helping to Ensure Food Safety and Food Quality
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Honoring Four Decades of Helping to Ensure Food Safety and Food Quality

On March 22, 2023, the QualiTru team met at the University of Minnesota’s Department of Food Science and Nutrition for an educational pilot plant tour led by Darrell Bigalke, founder of QualiTru Sampling Systems, dairy microbiologist, entrepreneur, and proud University of Minnesota alum.  As part of the celebration of QualiTru’s  40th anniversary, the team had…

The Effects of Gram-positive HRSF Bacteria on Fluid Milk Shelf Life (Part 2)
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The Effects of Gram-positive HRSF Bacteria on Fluid Milk Shelf Life (Part 2)

The first article in this series, Raw Milk Micro Testing, focused on Gram-negative bacteria in raw milk with the Preliminary Incubation (PI) Count and Fresh Standard Plate Count (SPC) tests. In this second installment, I would like to discuss another classification of bacteria (Gram-positive HRSF Bacteria) that was not known as a major issue in fluid…

Membrane Filtration Sampling
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Membrane Filtration Sampling

Membrane filtration is a widely used process in the dairy industry that separates specific components of milk and whey and then either concentrates or removes/reduces them. The technology used in cheese-making, whey protein concentration, fractionation of protein, and numerous other dairy processes requires special sampling considerations for both regulatory purposes and component analysis. It is…

Prevalence of Cold-tolerant Spore-forming Bacteria in the Milk Supply 
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Prevalence of Cold-tolerant Spore-forming Bacteria in the Milk Supply 

The shelf life of pasteurized fluid milk is challenged by bacterial contamination that enters the finished milk supply through two portals: a) contamination by Gram-negative psychrotrophic bacteria during processing after pasteurization; and b) contamination by Gram-positive spore-forming bacteria that enter primarily through the raw milk supply. In today’s processing environment, where post-pasteurization contamination is largely…

Low-Spore Milk Production—The Mantra and its Benefits
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Low-Spore Milk Production—The Mantra and its Benefits

Guest post: We are proud to introduce our guest blogger, David Blomquist. He is a well-known and respected consultant in the dairy and food processing industry. Read his full bio at the end of this article. Low-spore milk production has financial benefits for many producers and processors. Fluid milk plants can reduce shelf-life issues by…

Using Preliminary Incubation Count for Measuring Raw Milk Quality
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Using Preliminary Incubation Count for Measuring Raw Milk Quality

The Preliminary Incubation (PI) Count for measuring the quality of raw milk has become increasingly popular since the production of quality milk is the number one goal of dairy farmers and cooperatives. The PI test is especially sensitive to psychrotrophic bacteria. These particular bacteria can grow at colder temperatures, which is why dairy processors are encouraging…