INFLUENCE OF RAW MILK QUALITY ON LACTOBACILLUS ACIDOPHILUS MULTIPLICATION AND PROBIOTIC YOGHURT PRODUCTION
Eva Csutak
Abstract
Considering that the quality of raw milk is a prerequisite condition to obtain a good quality probiotic yoghurt, our studies aimed the measurement of milk factors which can affect the multiplication of probiotic lactic acid bacteria (LABs) Lactobacillus acidophilus (LA-5). The probiotic strains Bifidobacterium BB-12 and Lactobacillus acidophilus LA-5-we used for trials- are tested probiotics by Christian Hansen company. We studied comparatively raw and pasteurized milk, their chemical composition and the correlations between the spontaneous microbial flora (NTG) found in milk samples and the impact of this flora on the multiplication of LABs. We investigated as well the effect milk proteins, added prebiotics (lactose, molasses) on pH and LAB development, the influence of NTG (number of total germs), NCS (somatic cells number) in raw milk before and after pasteurization, on lactic fermentations and LA-5 (Lactobacillus acidophilus) Generally multiplication of LA-5 strains was reversely correlated with NTG values. There is a direct correlation between presence of prebiotics and probiotic bacteria activity.
INFLUENTA CALITATII LAPTELUI MATERIE PRIMA ASUPRA ÎNMULTIRII BACTERIEI LACTOBACILLUS ACIDOPHILUS SI A PRODUCTIEI DE IAURT PROBIOTIC
Eva Csutak
Rezumat
Tinând cont de faptul, ca în obtinerea iaurtului probiotic , calitatea laptelui materie prima are un rol foarte important, scopul acestei lucrari consta în determinarea influentei calitatii laptelui asupra multiplicarii si activitatii bacteriei Lactobacillus acidophilus( LA-5) folosita la testari. LA-5 este o cultura probiotica pura de Lactobacillus acidophilus de la firma Christian Hansen.
Am studiat laptele materie prima din zona Harghita, determinând parametrii chimici ai laptelui, numarul total de germeni, numarul celulelor somatice si influeta acestora asupra multiplicarii bacteriilor LA-5 în urma productiei de iaurt probiotic.
Viteza de multiplicare a bacteriilor probiotice LA-5 este invers proportional cu numarul total de germeni al laptelui materie prima si este în corelatie directa cu parametrii fizico-chimici ai laptelui cum ar fi continutul de lactoza sau grasimea.
