subject: enzymes

The Bacterial Diversity in Raw Cow Milk During Its Transport and Storage

The Bacterial Diversity in Raw Cow Milk During Its Transport and Storage

Pasteurization helps make raw cow milk safe for human consumption, but it doesn’t get rid of all bacteria. These remaining bacteria can cause spoilage, thus affecting the shelf life and quality of milk products and leading to wastage. Knowing what bacteria are present in milk before and during milk processing could help identify sources of spoilage and find ways to get rid of them. Read More...

Dairy Protein Digestion: Life in the Slow Lane

Dairy Protein Digestion: Life in the Slow Lane

Foods traveling from the mouth to the intestines are a bit like drivers off to work on a four-lane interstate. Some foods get in the fast lane and are quickly digested, whereas others stay in the slow lane, taking longer to reach their final destination. Why some foods are speed demons and others Sunday drivers depends on the particular properties of the nutrients in the foods. For example, proteins take longer to break down in the stomach than do carbohydrates, and milk contains some of the slowest digesting proteins of all. What makes milk proteins such slow pokes? Read More...

De-stressing with Dairy

De-stressing with Dairy

When, a few years ago, researchers analyzed fecal samples from volunteer undergraduates at Swinburne University of Technology, in Victoria, Australia, they didn’t necessarily expect to find evidence of the students’ examination stress. Yet the fecal lactic acid levels—reflecting the amount of “good bacteria” of the genus Lactobacillus in the students’ guts—took a dive during the exam period. In other words, exam stress had caused the volunteers’ intestines to become more favorable environments to pathogenic organisms. As the exams went on, things only got worse: the researchers observed day-by-day reductions in the undergraduates’ fecal lactic acid levels. This couldn’t have been because exam-period diets were messing with the students’ health—the only significant dietary change was an increase in coffee consumption. Read More...

Training Your Body to Digest Lactose

Training Your Body to Digest Lactose

The common understanding of the inability to properly digest lactose is that it’s all about genetics: either a particular gene in cells lining your upper intestine—which enables everyone to digest lactose as an infant—becomes inactive as you grow up, or it doesn’t. But the truth is less cut and dry. In fact, there is some recent and gathering evidence to suggest that those who suffer the symptoms of lactose intolerance could be better off by frequently consuming small quantities of the sugar that bothers them. Read More...

Accounting for Lactase Mutants

Accounting for Lactase Mutants

Back in the 50s and 60s, work on lactose intolerance was often published under cringeworthy and blunt racial titles. A Nature article from 1969 sums it up with ‘Can Asians Digest Milk?’ It was also probably a subliminal non-accident that ‘lactose intolerance’—which is the typical condition for adult humans—became common parlance for a trait for which those with northern European ancestry are the real mutants. Many decades on, the genetic basis of the ability to digest lactose has been largely pinned down. As it turns out, there are different genetic reasons for the mutants’ lactose tolerance in the various populations that drink milk without intestinal incident, and the gene that confers mutant power in Europeans is only part of the story. That research history is discussed below, along with recent work that has extended the field’s reach beyond genetics. Investigations of the transcontinental basis of lactose tolerance are now providing insights into mankind’s cultural, as well as biological evolution. Read More...

Producing Human Milk Sugars for Use in Formula

Producing Human Milk Sugars for Use in Formula

It’s well known that human milk is good for you (1-5). Sugars, called oligosaccharides, form the third largest component of human milk and have been associated with many beneficial effects. These human milk oligosaccharides (HMOs) have been shown to influence the composition of the gut microbiome, modulate the immune system, and help protect against pathogens (6-11, 22) Given the various benefits of HMOs, there has been a lot of interest in figuring out how to introduce HMOs into formula. However, more than 200 human milk oligosaccharides have been discovered so far, and their variety and complexity makes them challenging to synthesize (21-23). Read More...

Milk Protein Comparison Unveils Nutritional Gems for Human Infants

Milk Protein Comparison Unveils Nutritional Gems for Human Infants

As any new parent can tell you, human newborns are very needy—and for good reason. Born at an earlier developmental stage than their primate relatives, human infants must accomplish a great deal of fetal development (some say the equivalent of nine more months!) outside of the womb. Responsibility for this “fourth trimester” falls squarely on the shoulders of human breast milk, and so it is no surprise that decades of research have searched for attributes in human milk that support the unique developmental needs of human infants. While much of the focus has gone to milk fats and carbohydrates, a new study has turned the attention to milk proteins (1). Utilizing new methods in protein identification, Beck et al. present the most comprehensive human milk proteome (the list of the types and quantities of all proteins in milk) to date, as well as the first milk proteome for a nonhuman primate, the rhesus macaque. Despite having less total protein than rhesus macaque milk, Beck et al. found that human milk has more than three times the types of proteins in rhesus milk and higher quantities of nearly every milk protein that the two species share. Their findings demonstrate that from digestion, to immunity, to neurodevelopment, human infants get more of a boost from milk proteins than their primate cousins. Read More...