Abstract

Global milk product demand has been rapidly growing in the past decade, which is reflected in an increased demand for milk powders. The New Zealand dairy industry is capitalising on this by shifting its product portfolio towards milk powders. However, current international product specifications in combination with New Zealand milk composition and an industry objective to maximise farm profitability makes the industry deficient in milk lactose. This study aimed to determine how lactose deficit or surplus is influenced by changes in the product portfolio. In order to quantify this lactose balance, a computer simulation model was used (Moorepark Processing Sector Model). The 2012 New Zealand milk production (19.129 billion litres, milkfat concentration (4.99%), protein concentration (3.82%) and lactose concentration (4.70%, anhydrate)) was used within the analysis. Four manufacturing portfolio scenarios were investigated with different proportions of milk diverted to whole milk powder production (80%, 60% (current proportion), 30% and 10%). The model simulated the total production of whole milk powder, skim milk powder, casein, whey powder, buttermilk powder, butter and cheese. Whole milk powder production varied from 2,292,000 tonnes for the 80% scenario to 286,000 tonnes for the 10% scenario. Lactose mass balance varied from 214,000 tonnes in deficit for the 80% scenario to 510,000 tonnes in surplus for the 10% scenario. These analyses indicate that as more whole milk powder is produced, milk from current New Zealand cows results in an increased deficit of milk lactose. The national breeding objective could be adjusted to reflect changes in the future product portfolios to better align the composition of milk with the likely product mix.

NW, Sneddon, N Lopez-Villalobos, RE Hickson, L Shalloo, DJ Garrick, and U Geary

Proceedings of the New Zealand Society of Animal Production, Volume 74, Napier, 215-219, 2014