Validation of Milk Product Pasteurization by Alkaline Phosphatase Activity

Abstract

The standard practices for indirectly assessing the pasteurization status of milk products are primarily based on the thermal in activation kinetics of the endogenous milk enzyme, alkaline Phosphatase (ALP).This review provides an invaluable, tool for both regulatory and in house process control and validation. Endogenous milk ALP manifests a slightly higher heat resistance than the pathogenic micro flora upon which pasteurization time and temperature requirements are based. Therefore, ALP activity is recognized and accepted as the method of choice for the rapid validation of milk product pasteurization. However, ALP assays have notable limitations that must be understood if they are to be administered and interpreted correctly and the results are to be applied judiciously. Issues such as the reactivation of heat denatured ALP and the presence of both heat stable and labile microbial ALP are addressed. A discussion of ALP in the milk of non-bovine speciesis presented based on the limited literature available. Also brief discussion of research involving alternative pasteurization indicators is presented. This review article is intended to summarize the pertinent details of the ALP assay for dairy products (considering the basis and limitations of various methods) and the processing, handling, and known compositional factors that influence the assay results.

The use of alkaline phosphatase and possible alternative testing to verify pasteurisation of raw milk, colostrum, dairy and colostrum‐based products

“…The use of alternative analytical methods to determine the ALP activity is acceptable when the methods are validated against these reference methods. Methods applied for the analysis of ALP activity in milk and dairy products can be classified according to three different measuring principles: fluorimetric, colorimetric and chemiluminescent as recently reviewed by Punoo (2018) and summarised in Table 3.…”

Avaliação de métodos colorimétricos quantitativos e qualitativos da enzima fosfatase alcalina no leite

“…Segundo Castanheira (2012) a enzima fosfatase alcalina é amplamente utilizada para verificar a eficiência da pasteurização, pois indica se o processo térmico atingiu a temperatura adequada e se o leite pasteurizado foi contaminado novamente pelo leite cru. A maior parte dessa enzima se encontra associada à membrana dos glóbulos de gordura do leite cru, e a sua concentração no leite varia de acordo com a espécie, estação do ano, período de lactação, idade e estado de saúde do animal (HILAL, 2018).…”

“…imunoquímicos. Esses métodos foram adotados para uso ao longo de muitos anos, entretanto, apenas os tipos fluorimétrico, quimioluminescente e colorimétrico foram reconhecidos e validados para verificação de pasteurização na indústria de laticínios(PUNOO, 2018). Os testes descritos foram adaptados de Standard Methods for Examination ofDairy (MARTH, 1978) e servem para análise de leites e derivados.…”