The science of dairy

It is a sign of the times that the International Dairy Federation chose to hold its parallel symposia on cheese science & technology, and concentration and dried milk products. The two sectors are closely intertwined due to the nature of cheese processing, and it made sense for experts in both sectors to mingle.

Veronique Pinet, chief economist at Centre national interprofessionnel de l’économie laitiére (CNIEL), detailed the many challenges facing dairy in Europe: the loss of the Russian market and the downturn of the Chinese one. “Globally, the price situation is rather bad, and we’ve had price decreases continually over the past two years. Trade remained quite stable in 2015, but growth is not what was expected a few years ago,” she remarks.

Over the last two decades, the companies supplying dairy have moved geographically towards Asia, with seven companies with more than US$3 billion in turnover in Asia. However, the industry remains fragmented – for example, Lactalis only accounts for four per cent of global market share, and there are a huge number of smaller groups as part of the market.

Investment has been heavy, particularly in the dry sector of dairy, with a total of €8.8 billion invested in 189 projects, mainly in the cheese producing regions of Europe, the Americas and New Zealand. Groups such as Fonterra are seeking investment in Europe, in order to secure sourcing of dry dairy products, she notes.

Kevin Lane, the chief executive of Irish group Ornua, notes that the country’s most recent challenge has been to operate in a non-quota environment. However, investments have been underway. For example, around €20 million has been spent for a facility for making white cheese in Saudi Arabia, which is now the fifth largest importer of cheese globally.

Consumer needs

Tim Coolbear, consumer science manager at Fonterra’s R&D Centre, detailed how consumer needs vary from country to country, with differences in how dairy is consumed in each one. Food safety is extremely high now in consumer consciousness, he notes, so protecting the supply chain integrity is very important. On the other hand, they are “extremely confused about what’s in food, so providing understanding and analysis for consumers is also important,” he adds. “The science has to be seen as enhancing the products, as in some markets, science is not trusted.”

Hans Westerbeek, ingredients development director at FrieslandCampina notes there are key trends for dairy ingredients. These include nutrition and healthy lifestyle, minimum processing, affordability, and natural and pure. He notes that after a move to vegetable fat for infant formula in the past, manufacturers are returning to milk fat, having seen the health benefits of milkfat. “There is more absorption of calcium and nutrients with milkfat,” he says.

David Potts, a researcher at the University of Minnesota, looked at the sensory fractionation of dairy products, and Shane Crowley of University College of Cork in Ireland examined the next generation of milk protein ingredients. David Everett, Leprino Foods Professor at California Polytechnic State University, finished the session with a talk on structural nutrition and why it’s more than ‘calories in, calories out.’

Split sessions

One of the indicators of the interest in whey technology was the size of the rooms at the symposium. The amount of space was skewed towards whey, the relative newcomer, but both were well attended. Tim Guinee of Teagasc kicked off the cheese science session with a discussion of protein standardisation and cheese yield, where he noted that seasonal variations are present for protein levels in bovine milk, and this also depends on the diet. This can have an impact on the cheese compositions and quality, and how varied gel firmness is in the cheese. “Salt reduction can have a significant effect on cheese quality,” Guinee says. He also notes that using high protein powder with milk can impact on gelation of the cheese after rennet addition.

S.T. Pedersen explained her experiments in the manufacture of cheddar cheese using micellular casein isolate (MCI). The advantage to this is high yield and any additives stay in the cheese, and there is also low moisture loss, she notes. The cheese was compared to a normal cow’s milk cheese both with a dry matter of 56 per cent. It was found that 12kg of MCI milk produced 8-9 kg of cheese at 30 per cent moisture. However, the experimental cheeses were softer, more acidic and bitter than the commercial cheddar cheese, she states.

RA Ibáñez of the University of Wisconsin noted that acidity is a common effect in cheddar cheese and it is a major flavour defect. It is caused by lactic acid in cheese. He asked what controls the final pH and said that there are many different strategies to control acidity in cheese, including adding water into the curd. However, this last solution affects the texture and functionality of the cheese. Balancing lactose and casein is important. His tests used ultrafiltration to try and standardize protein content, with the hypothesis that standardising casein and milk in cheese milk would control acidification. The cheese made from milk with lower lactose had the highest pH, and a decrease in soluble calcium, he notes.

Peter Dekker of DSM Food Specialities in the Netherlands examined the effect of proteases on cheese making.

Concentrate

Melina Corredig of Gay Lea Foods at the University of Guelph in Canada spoke about structure functions of casein micelles in concentrated milk. She notes there is potential for new functional ingredients, and people have to understand processing conditions and the history of processing concentrates. Concentration is easily related to the behaviour of the milk, she says.

John Bonke of GEA says that 408 million tonnes of milk were received at dairies in 2014 globally, which was made into 138 million tonnes of drinking milk and 20 million tonnes of cheese. Around 85 million tonnes of powder products were made from fresh milk. More than 60 per cent of dairy delivered is now being processed into powders, he notes.

Cordelia Selomulya of Monash University in Australia, also confirmed that powders are on the upswing, with powders making up more than 40 per cent of production in her country, most of which is exported from Australia. “There is increased demand for added value products,” she says.

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