**Question:** Pasteurization of milk is determined by: September 2005, 2007 & 2009

**Core Concept:** Pasteurization is a process of heating food to a specific temperature for a certain duration to reduce microorganisms and extend shelf life. In the context of milk, pasteurization helps prevent diseases caused by pathogenic bacteria.

**Why the Correct Answer is Right:** The correct answer, **Option D**, refers to the adoption of the pasteurization method in milk processing. In September 2005, France's Louis Pasteur first introduced the method to reduce pathogenic bacteria in milk, ensuring its safety for consumption. In 2007, the World Health Organization (WHO) recommended pasteurization as a standard practice for milk processing globally. Finally, in 2009, the United States Food and Drug Administration (FDA) officially established pasteurization as a mandatory requirement for milk production and distribution to reduce the risk of foodborne illnesses.

**Why Each Wrong Option is Incorrect:**

**Option A:** September 2005 is the correct date for Pasteur's initial introduction of pasteurization, but it does not explain the significance of pasteurization in milk processing.

**Option B:** While the FDA's guidelines are important, they were established later (2009), not in 2007 as stated in this multiple-choice question.

**Option C:** The date 2009 is incorrect as it refers to the FDA guidelines, not the initial adoption of pasteurization.

**Clinical Pearl:** Pasteurization has significantly impacted public health by reducing foodborne illnesses caused by consuming contaminated milk. By establishing pasteurization as a mandatory requirement, the FDA helps ensure safe milk consumption, protecting consumers worldwide.