Conversión de las explotaciones de vacuno de leche a la producción de leche A2 ante una posible demanda del mercado: posibilidades e implicaciones

Abstract

El mercado de la leche de vaca, tras la desaparición de las cuotas lácteas, está provocando una importante restructuración en el sector. Una de las alternativas que están desarrollando, fundamentalmente las pequeñas explotaciones familiares, es la diferenciación de sus productos. En ese contexto, ha aparecido un tipo diferenciado de leche conocida como leche A2. Esta se caracteriza por estar libre de la variante A1 de la proteína β-caseína que, debido a una mayor producción de β-casomorfina-7 tras la digestión, puede dar lugar a intolerancias y afecciones gastrointestinales. En este trabajo se analizan las posibilidades e implicaciones de una selección a favor de la β-caseína A2 en el caso concreto de las explotaciones familiares de Guipúzcoa. Los resultados obtenidos a partir de 1868 hembras genotipadas muestran que la frecuencia del alelo que codifica la proteína A2 es 0,55, y no se han encontrado asociaciones desfavorables entre el alelo A2 y el valor genético para caracteres productivos, funcionales y morfológicos, ni con otros genes ni haplotipos. Bajo esta situación de partida, y empleando exclusivamente toros A2A2, la utilización o no de semen sexado, junto con las diferentes ratios de reposición que se apliquen, determinarán el periodo y el coste económico de la conversión de los rebaños a la producción de leche A2. En un escenario de costes razonables esta se estima entre los 8 y los 15 años, pudiendo llegar a suponer a una explotación de 150 vacas unos costes de unos 6.000 y 1.000 €/año, respectivamente.

A2 Milk: New Perspectives for Food Technology and Human Health

“…Thus, it is necessary to have a large potential market and a milk price premium to make the whole process profitable. Many people could be interested in consuming only A2 milk, but only if its beneficial effects for human heath have been demonstrated by scientific evidence [ 7 ]. A recent work investigating consumers’ awareness of A2 milk [ 21 ] revealed that the factors that condition consumers to buy these dairy products are price; origin; and quality certification, such as “organic” or “traditional”.…”

“…Lactose-intolerant individuals suffer diverse digestive symptoms after milk ingestion, such as abdominal pain, bloating sensation, stool frequency changes, and stool consistency changes [ 6 ]. Another option to increase dairy profitability is the search for differentiated products with a higher added value [ 7 ], such as milk or dairy products with associated benefits to human health. Food with health claims shows higher prices than those observed in high-volume food segments [ 8 ].…”

“…In recent years, a new type of cow’s milk, named “A2 milk”, has been introduced in the market. This type of milk was first commercialized in New Zealand and has since been gaining a presence in the markets of several countries [ 7 ]. A2 milk is characterized by being free of the A1 variant of β-casein: a protein that represents approximately 30% of the caseins in cow’s milk [ 8 ].…”

“…A2 milk is characterized by being free of the A1 variant of β-casein: a protein that represents approximately 30% of the caseins in cow’s milk [ 8 ]. By genotyping dairy cows and using semen from selected bulls, or genotyping and selecting only A2 calves for replacement, it is possible to obtain a dairy farm producing only A2-type milk [ 7 ]. The coding gene in β-casein synthesis is the CNS2 gene, for which 13 different allelic variants have been described (A1, A2, A3, B, C, D, E, F, G, H1, H2, and J) [ 14 ].…”

DNA extraction procedures and validation parameters of a real-time PCR method to control milk containing only A2 β-casein

“…Thus, BCM-7 is thought to be responsible for potential adverse outcomes associated with A1 β-casein consumption, and it has been highly discussed in the literature (Brooke- Taylor et al, 2017). Despite the uncertainty still exist, A2 milk, produced by homozygous A2A2 cows and thus only containing A2 β-casein, has emerged as an alternative product in the dairy sector (Alfonso et al, 2019;Bentivoglio et al, 2020;Oliveira Mendes et al, 2019).…”