Tag: Dairy chemistry

According to research published in the *International Dairy Journal*, the visual appearance of dairy products significantly influences consumer buying decisions. The characteristic opaque white color that consumers expect is a direct result of several components within milk working in tandem. So, what makes dairy white? It's a fascinating combination of proteins, fats, and the physics of light that give dairy its signature hue.

The chemical process of milk turning sour is a natural phenomenon driven by microscopic organisms. The specific chemical that makes milk sour is lactic acid, which is produced when certain bacteria in the milk consume its natural sugar, lactose, in a process known as fermentation.

Fresh cow's milk typically has a pH ranging from 6.4 to 6.8, which is slightly acidic on the pH scale. Despite its close proximity to a neutral pH of 7, milk contains lactic acid, and its pH level is a key indicator of its freshness and overall quality. This reading is not static and changes due to various biological and environmental factors.

Nearly 90% of milk is water, but its opaque, white appearance is due to a special colloidal system known as an emulsion. This means milk is an oil-in-water emulsion, a stabilized mixture of two immiscible liquids where fat is the dispersed phase and water is the continuous medium.

Fresh cow's milk has a naturally slightly acidic pH, typically ranging between 6.4 and 6.8. Understanding which acid content is in milk reveals that this initial acidity is due to a combination of natural compounds, which differs fundamentally from the lactic acid that develops as milk sours.

Approximately 87% of cow's milk is water, making it the most abundant component. However, the remaining portion contains a complex blend of many organic and inorganic chemicals, raising the question: what chemical is present in milk?. It is not a single chemical but a variable, heterogeneous mixture.

Most people know that sour milk is acidic, but fresh cow milk is naturally slightly acidic, not neutral. The primary acid involved is lactic acid, which increases as the milk spoils, but other acids are naturally present too.

Approximately 98% of milk fat is composed of triglycerides encapsulated within complex structures known as milk fat globules (MFG), forming a natural emulsion. However, these globules are not uniform; they exist in distinct forms that profoundly influence the texture, stability, and nutritional properties of milk and its derivatives.

While many people assume milk contains lactic acid, fresh milk is actually only slightly acidic due to natural compounds like phosphates and citrates. The distinctive sour flavor and higher acidity we associate with spoiled or fermented dairy is a result of lactic acid, which is produced by bacteria over time.

Containing over 87% water, whole milk is a complex aqueous mixture of fat, protein, lactose, minerals, and vitamins. These varied substances are responsible for its nutritional value and unique properties, with hundreds of different chemical compounds present in a single glass.