Influence of Different Growth Conditions on the Kefir Grains Production, used in the Kefiran Synthesis

Abstract

The purpose of this study was to optimize the kefir grains biomass production, using milk as culture media. The kefir grains were cultured at different changed conditions (temperature, time, shaker rotating speed, culture media supplemented) to evaluate their effects. Results showed that optimal culture conditions were using the organic skim milk, incubated at 25°C for 24 hours with a rotation rate of 125 rpm. According to results, the growth rate was 38.9 g/L for 24 h, at 25°C using the organic milk -OSM, 36.87 g/L during 24 hours, optimal time for propagation process gave 37.93 g/L kefir grains biomass when the effect of temperature level was tested. The homogenization of medium with shaker rotating induced a greater growth rate, it was obtained 38.9 g/L for 24 h, at 25°C using rotation rate at 125 rpm. The growing medium (conventional milk) supplemented with different minerals and vitamins may lead to improve the growth conditions of kefir grains biomass. The optimization of the growth environment is very important for achieving the maximum production of kefir grains biomass, substrate necessary to obtain the polysaccharide kefiran.

Thermal conductivity measurement of biological materials: a case study in moderate ambient temperatures

“…Thermal properties of those components were calculated according to the published models . The mass fractions of water, protein, fat, carbohydrate, fiber and ash in kefir grains were assumed after Pop et al as equal to 0.9, 0.03, 0.003, 0.06, 0.007 kg of constituent kg −1 kefir grain, respectively. Volume fraction of air in kefir grains (porosity) was measured.…”

“…Moisture content in kefir grains used in the present study was 895 ± 5 g water kg −1 kefir grains. Pop et al reported that moisture content in kefir grain is in the range between 880 and 900 g water kg −1 kefir grains that is in the agreement with our findings.…”

“…Unlike in the heating process, temperature below 30 °C suppressed the activity of grains microflora and did not induce significant changes in grains microstructure, which could explain why cooling did not affect the thermal conductivity of kefir grains. Pop et al demonstrated that time is also an important determinant of kefir grains biomass. The authors observed a substantial increase in biomass during the first 24 h of incubation.…”

Optimization of Milk Type and Physical Factors for Reduction of Alcohol Content in Kefir

“…Milk type and its chemical composition (proteins, lipids, carbohydrates, minerals and vitamins), impacted on KG biomass (Table 3), leading to variation in the resulted KG biomass. In this respect, Pop et al, (2014) reported that biomass of KG greatly affected by the type of milk, and the organic skim milk incubated at 25°C for 24 h with a rotation rate of 125 rpm were the optimal conditions for produce the highest KG biomass. These results might be attributed to the kind of substrates, necessary for the growth of KG.…”

Evaluation De Leffet Protecteur Du Lait De Chevre Fermente Par Le Kefir Et Enrichi a La Caroube Contre Lulcere Gastrique Induit Par Lethanol Chez Le Rat.

“…Lors du renouvellement du lait, les grains ont été rincés à l'eau stérile et égouttés. Ces manipulations d'entretien des grains se faisaient à température ambiante (Pop et al 2014).…”