Milk-and-Dairy-Products-in-Human-Nutrition-FAO

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Milk and dairy products in human nutrition
Dry buttermilk (0899): no definition given.
Nutrient profile of milk powder
The heat treatment involved in drying results in denaturation of milk whey proteins
and formation of whey protein–casein protein aggregates. The heat treatments are
also associated with the loss of vitamins. Sharma and Lal (2002), for example, found
that skimmed-milk powder made from buffalo milk contained 12 percent less thiamine,
10 percent less riboflavin, 13 percent less vitamin B 6 , 16 percent less folate and
19 percent less total vitamin C than the original milk and that losses of water-soluble
vitamins continued during storage in sealed polyethylene bags.
Marconi and Panfili (1998) showed that while some of the characteristics of mare
milk were retained in milk powder (e.g. high whey protein, low casein, high PUFA,
particularly C18:2 and C18:3), other nutrients were partly or completely destroyed:
these include lysine (12 percent loss), vitamin A (RE) (40 percent loss), tocopherols
(60 percent loss), riboflavin (100 percent loss) and vitamin C (96 percent loss).
Similar losses were observed in cow milk powder prepared by spray-dried process:
lysine (5 percent loss), vitamin A (RE) (60 percent loss), tocopherols (40 percent
loss), riboflavin (30 percent loss) and vitamin C (93 percent loss).
3.3.2 Heat treatments and microbiocidal measures
FAO and WHO (2009) gives the following definitions for various heat-treatments
or microbiocidal measures carried out on milk:
Thermization: “The application to milk of a heat treatment of a lower intensity
than pasteurization that aims at reducing the number of micro-organisms. A
general reduction of log 3–4 can be expected. Micro-organisms surviving will
be heat-stressed and become more vulnerable to subsequent microbiological
control measures”.
Thermization heat treatments can range from heating at 52–67 °C for between
20 seconds and about half an hour (Valdramidis et al., 2011). Thermization is the
heating of raw milk for at least 15 seconds at a temperature between 57 °C and 68 °C
such that after treatment the milk shows a positive reaction to the phosphate test
(CEC, 1992).
Pasteurization: “Pasteurization is a microbiocidal heat treatment aimed at reducing
the number of any pathogenic micro-organisms in milk and liquid milk products,
if present, to a level at which they do not constitute a significant health hazard.
Pasteurization conditions are designed to effectively destroy the organisms Mycobacterium
tuberculosis and Coxiella burnettii”.
The process criteria are given as the following: “According to validations carried
out on whole milk, the minimum pasteurization conditions are those having bactericidal
effects equivalent to heating every particle of the milk to 72 °C for 15 seconds
(continuous flow pasteurization) or 63 °C for 30 minutes (batch pasteurization)”.
UHT (ultra-high temperature) treatment: UHT treatment of milk and liquid
milk products “is the application of heat to a continuously flowing product using
such high temperatures for such time that renders the product commercially sterile