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

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Milk and dairy products in human nutrition
Mycotoxins
Aflatoxins, which are produced by Aspergillus flavus and Aspergillus parasiticus,
may be present in animal feed. Where cattle consume feed contaminated with
aflatoxin B 1 , aflatoxin M 1 is the main aflatoxin in milk or dairy products due to a
conversion from aflatoxin B 1 . Aflatoxin M 1 is a genotoxic carcinogen which poses a
significant risk to human health even at low concentrations (IARC, 1993). The risks
from aflatoxin exposure from milk need careful consideration, particularly in infants
and young children. The Codex Alimentarius Commission has set the maximum
limit for aflatoxin M 1 in milk at 0.5 μg/kg (FAO and WHO, 1995a).
Aflatoxin contamination of milk can be prevented by preventing fungal growth
in feed.
Food additives, flavours and processing aids
Chemicals added to foods include food additives (such as stabilizers, acidifiers,
emulsifiers, colours, thickeners and preservatives), flavouring substances and
processing aids. These chemicals impart a flavour, protect food from microbiological
deterioration, enhance functional characteristics or improve shelf-life and
appearance. Levels at which these chemicals are likely to become harmful to human
health are generally many times greater than they would occur under normal usage
(Fischer et al., 2003). However, where weak controls and practices do exist, the
prescribed usage levels may be exceeded, resulting in a harmful or even toxic effect.
ADIs for a range of food additives are given in the Codex Alimentarius General
Standard for Food Additives (FAO and WHO, 1995b).
Chemicals formed during processing or final use
Some substances can be formed or enter the milk products during processing.
Examples include the following:
• Advanced glycation end products (AGEs) are formed during heat processing
of foods containing protein and carbohydrate. Infant formulas are heated
during the manufacturing process to ensure their microbiological safety and
therefore AGEs may be formed. AGEs may play an important adverse role
in atherosclerosis, diabetes, aging and chronic renal failure (Krajcovicová-
Kudlácková et al., 2002).
• Contamination with ITX, normally contained in the ink used to print on
packaging materials, has been reported in some baby milk and other dairy
products (Benetti et al., 2008).
• BPA is used to make polycarbonate plastics and epoxy resins. Polycarbonate
is widely used in food contact materials, such as infant feeding bottles and
food containers while epoxy resins are used as protective linings for canned
foods, glass jars including containers used for infant formula. These uses
result in consumer exposure to BPA through the diet. There are concerns
about possible adverse human health effects especially on reproduction, the
nervous system and behavioural development in consequence and due to the
relatively high exposure of very young children compared with adults. An
FAO/WHO expert meeting convened in 2010 examined the available data on
this issue, and identified a number of gaps in knowledge and provided a range
of recommendations for the generation of further information and the design