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challenges for liquid milk. However, improvements in milk handling would reduce
the possible development of off-flavours in the final milk product for consumption
(Loewenstein et al. 1980).
Yoghurt
Yoghurt is one of the fermented milk products made from goat milk. It has a long
tradition in many countries (Tamime and Robinson 2007a). The same process used
to produce yoghurt from cow milk could be used to produce goat milk yoghurt. A
standard procedure for set-style yoghurt from goat milk is shown in Fig. 2. As
mentioned before, homogenisation is normally used to reduce the size of the fat
globules and enhance the technological properties of milk and to reduce the creaming effect. It is mostly practised in cow milk processing because of the large fat
globule size in this milk. Homogenisation of goat milk, before yoghurt production,
was however found to improve curd tension and viscosity of yoghurt (Abrahamsen
and Holmen 1981). Heat treatment of milk during yoghurt processing is very essential to the technological properties of goat milk before processing. Heat treatment of
milk, i.e. pasteurisation, restores the structure of casein micelles through recovering
of the soluble β-CN and micellar calcium, dissolved to the serum phase during cold
storage of milk (Raynal-Ljutovac et al. 2005). During yoghurt making, high heat
treatment is employed (for instance, 80 °C for 30 minutes). At this temperature,
Fig. 1 Process chart for the goat liquid milk beverage. (Source: Park and Guo (2006))
I. A. Ketto et al.
challenges for liquid milk. However, improvements in milk handling would reduce
the possible development of off-flavours in the final milk product for consumption
(Loewenstein et al. 1980).
Yoghurt
Yoghurt is one of the fermented milk products made from goat milk. It has a long
tradition in many countries (Tamime and Robinson 2007a). The same process used
to produce yoghurt from cow milk could be used to produce goat milk yoghurt. A
standard procedure for set-style yoghurt from goat milk is shown in Fig. 2. As
mentioned before, homogenisation is normally used to reduce the size of the fat
globules and enhance the technological properties of milk and to reduce the creaming effect. It is mostly practised in cow milk processing because of the large fat
globule size in this milk. Homogenisation of goat milk, before yoghurt production,
was however found to improve curd tension and viscosity of yoghurt (Abrahamsen
and Holmen 1981). Heat treatment of milk during yoghurt processing is very essential to the technological properties of goat milk before processing. Heat treatment of
milk, i.e. pasteurisation, restores the structure of casein micelles through recovering
of the soluble β-CN and micellar calcium, dissolved to the serum phase during cold
storage of milk (Raynal-Ljutovac et al. 2005). During yoghurt making, high heat
treatment is employed (for instance, 80 °C for 30 minutes). At this temperature,
Fig. 1 Process chart for the goat liquid milk beverage. (Source: Park and Guo (2006))
I. A. Ketto et al.