Protein in Yogurt
As the global dairy market continues to grow, yogurt in particular stands out as one of the fastest rising sectors. This is especially true with the increased popularity of Greek yogurt and recent advent of non-dairy yogurt alternatives, such as almond, coconut, and soy. A 2015 study showed that yogurt consumption on a daily basis rose from 4.7 % in 1999 to 9.3 % in 2013 from a survey population of 33,932 US adults.i Much of yogurt’s growth can be attributed to its health benefits, which include being a good source of protein, probiotics, fruits, and other nutrients.
Protein is an essential measurement for yogurt manufacturers as it directly influences product thickness and definition (i.e. Greek yogurt has approximately twice the amount of protein as traditional yogurt). Yogurt is produced by adding live bacterial cultures to milk after it has been exposed to elevated temperature(s) and subsequently cooled. Bacterial cultures ferment the lactose in the previously heat-treated milk, which produces lactic acid. This decrease in pH, in combination with the previous heat treatment, causes milk proteins (casein and whey) to denature from higher order structures and form clusters. Yogurt thickens as the proteins unwind and bind together. In general, the higher the protein content the thicker the yogurt.
The Sprint™ protein analyzer is an ideal solution for yogurt manufacturers for testing both in-process and finished yogurt products. The technology is based on a rapid green chemistry process allowing for direct protein detection in less than 5 minutes. A proprietary iTag® solution is mixed with the sample and binds directly to the backbone of the proteins, specifically the basic amino acids (Lysine, Arginine, and Histidine). This rapid and direct protein detection technique is not influenced by nitrogen containing adulterants and does not use any hazardous reagents associated with wet chemical techniques, such as Kjeldahl. Additionally, the unwinding (denaturation) of proteins during the yogurt production process does not reduce the Sprint’s efficacy but rather exposes more of the backbone for binding with iTag solution.
i Nielsen SJ et al., Trends in Yogurt Consumption - US Adults - 1999-2012, The FASEB Journal, April 2015, vol 29(1).