Technological variables influencing the growth and stability of a silage inoculant based on spray‐dried lactic acid bacteria

Abstract

Aims To investigate the influence of different culture media and fermentation conditions on growth performance and viability of three lactic acid bacteria (LAB) strains with potential as silage inoculants, and to optimize spray‐drying in order to enhance survival to dehydration and storage stability. Methods and Results In house‐formulated MRS was a suitable low‐cost culture medium for Lactobacillus plantarum Hv75, Pediococcus acidilactici 3903 and L. buchneri B463. Uncontrolled pH biomass production conferred enhanced stability during storage at 4°C after spray‐drying. The use of whey protein concentrate 35 (WPC)‐maltodextrin (M) as matrix, inlet temperature of 145‐150°C and air flow rate of 601 l h−1 was adequate for the production of dehydrated LAB. According to the desirability function, at this optimized condition, moisture content, yield and solubility were predicted to be 3·96, 73·68 and 90·36% respectively. Those conditions also showed a decrease of 0·855 log CFU per gram after drying, no loss in viability at 4°C for 6 months and 1 log CFU per gram reduction at 25°C. Conclusions Stable and economically feasible dehydrated LAB cultures were obtained using alternative culture media, fermentation under uncontrolled pH and optimizing spray‐drying process conditions through the desirability function method. Significance and Impact of the Study Our results can be utilized for efficient production and commercialization of several dry LAB.

From waste to worth: stability, bioaccessibility, and cellular antioxidant activity of microencapsulated red grape pomace phenolics

“…Therefore, the difference in protein content between SMP and WPC used in our study (330 and 800 g kg −1 , respectively) may explain the higher solubility of MD/SMP powders compared to MD/WPC powders. Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature 13,24 . These factors collectively explain the variations observed in blends containing S.…”

“…In this method, after desirability values are computed for each response variable, they are combined into a single desirability index by calculating their geometric mean in order to arrive at the overall desirability. 13,16,23 The independent variables affecting the quality of the microcapsules were the wall materials and evaluated concentrations. Response variables including retention of TP, TP content in microcapsule, loss of TP after 120 days of storage (at 4 and 25 °C), yield, moisture, and solubility were used as quality characteristics.…”

“…Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature. 13,24 These factors collectively explain the variations observed in blends containing S.…”

From waste to worth: stability, bioaccessibility, and cellular antioxidant activity of microencapsulated red grape pomace phenolics

“…Therefore, the difference in protein content between SMP and WPC used in our study (330 and 800 g kg −1 , respectively) may explain the higher solubility of MD/SMP powders compared to MD/WPC powders. Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature 13,24 . These factors collectively explain the variations observed in blends containing S.…”

“…In this method, after desirability values are computed for each response variable, they are combined into a single desirability index by calculating their geometric mean in order to arrive at the overall desirability. 13,16,23 The independent variables affecting the quality of the microcapsules were the wall materials and evaluated concentrations. Response variables including retention of TP, TP content in microcapsule, loss of TP after 120 days of storage (at 4 and 25 °C), yield, moisture, and solubility were used as quality characteristics.…”

“…Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature. 13,24 These factors collectively explain the variations observed in blends containing S.…”

Probiotic characterization of indigenous lactic acid bacteria isolates from chickens to be used as biocontrol agents in poultry industry

“…Growth rate in different culture media showed that MRS broth was the best growth medium for L. agilis 1235C and E. durans , while MRS + WP broth was the best growth medium for L. salivariu s. E. durans showed a better growth rate than ligilactobacilli in MRS broth; whereas in the other culture media its growth was lower than both ligilactobacilli. In general, alternative growth media used milk or whey permeate, a by‐product of the cheese manufacture (Blajman et al, 2020; Heenan et al, 2002). This product has been previously employed for LAB biomass production (Cerdeira et al, 2019), showing that its application is feasible at industrial levels.…”

A Multi-Sensor Mini-Bioreactor to Preselect Silage Inoculants by Tracking Metabolic Activity in situ During Fermentation

“…A few studies tested silage inoculants using MRS broth or the aqueous extract of silage crop ( Oude Elferink et al, 2001 ; Danner et al, 2003 ; Holzer et al, 2003 ; Graves et al, 2006 ; Arasu et al, 2015 ; Blajman et al, 2020 ). Fermentation characteristics, such as production of organic acids, decreasing dynamics of pH, and CO 2 production, depend on medium composition ( Danner et al, 2003 ; Blajman et al, 2020 ).…”

From waste to worth: stability, bioaccessibility, and cellular antioxidant activity of microencapsulated red grape pomace phenolics

“…Therefore, the difference in protein content between SMP and WPC used in our study (330 and 800 g kg −1 , respectively) may explain the higher solubility of MD/SMP powders compared to MD/WPC powders. Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature 13,24 . These factors collectively explain the variations observed in blends containing S.…”

“…In this method, after desirability values are computed for each response variable, they are combined into a single desirability index by calculating their geometric mean in order to arrive at the overall desirability. 13,16,23 The independent variables affecting the quality of the microcapsules were the wall materials and evaluated concentrations. Response variables including retention of TP, TP content in microcapsule, loss of TP after 120 days of storage (at 4 and 25 °C), yield, moisture, and solubility were used as quality characteristics.…”

“…Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature. 13,24 These factors collectively explain the variations observed in blends containing S.…”

Probiotic characterization of indigenous lactic acid bacteria isolates from chickens to be used as biocontrol agents in poultry industry

“…Growth rate in different culture media showed that MRS broth was the best growth medium for L. agilis 1235C and E. durans , while MRS + WP broth was the best growth medium for L. salivariu s. E. durans showed a better growth rate than ligilactobacilli in MRS broth; whereas in the other culture media its growth was lower than both ligilactobacilli. In general, alternative growth media used milk or whey permeate, a by‐product of the cheese manufacture (Blajman et al, 2020; Heenan et al, 2002). This product has been previously employed for LAB biomass production (Cerdeira et al, 2019), showing that its application is feasible at industrial levels.…”

A Multi-Sensor Mini-Bioreactor to Preselect Silage Inoculants by Tracking Metabolic Activity in situ During Fermentation

“…A few studies tested silage inoculants using MRS broth or the aqueous extract of silage crop ( Oude Elferink et al, 2001 ; Danner et al, 2003 ; Holzer et al, 2003 ; Graves et al, 2006 ; Arasu et al, 2015 ; Blajman et al, 2020 ). Fermentation characteristics, such as production of organic acids, decreasing dynamics of pH, and CO 2 production, depend on medium composition ( Danner et al, 2003 ; Blajman et al, 2020 ).…”

From waste to worth: stability, bioaccessibility, and cellular antioxidant activity of microencapsulated red grape pomace phenolics

“…Therefore, the difference in protein content between SMP and WPC used in our study (330 and 800 g kg −1 , respectively) may explain the higher solubility of MD/SMP powders compared to MD/WPC powders. Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature 13,24 . These factors collectively explain the variations observed in blends containing S.…”

“…In this method, after desirability values are computed for each response variable, they are combined into a single desirability index by calculating their geometric mean in order to arrive at the overall desirability. 13,16,23 The independent variables affecting the quality of the microcapsules were the wall materials and evaluated concentrations. Response variables including retention of TP, TP content in microcapsule, loss of TP after 120 days of storage (at 4 and 25 °C), yield, moisture, and solubility were used as quality characteristics.…”

“…Additionally, it has been observed that native starches have some restriction as wall materials, since the powders formulated with them have difficulty to dissolve at room temperature. 13,24 These factors collectively explain the variations observed in blends containing S.…”

Probiotic characterization of indigenous lactic acid bacteria isolates from chickens to be used as biocontrol agents in poultry industry

“…Growth rate in different culture media showed that MRS broth was the best growth medium for L. agilis 1235C and E. durans , while MRS + WP broth was the best growth medium for L. salivariu s. E. durans showed a better growth rate than ligilactobacilli in MRS broth; whereas in the other culture media its growth was lower than both ligilactobacilli. In general, alternative growth media used milk or whey permeate, a by‐product of the cheese manufacture (Blajman et al, 2020; Heenan et al, 2002). This product has been previously employed for LAB biomass production (Cerdeira et al, 2019), showing that its application is feasible at industrial levels.…”

A Multi-Sensor Mini-Bioreactor to Preselect Silage Inoculants by Tracking Metabolic Activity in situ During Fermentation

“…A few studies tested silage inoculants using MRS broth or the aqueous extract of silage crop ( Oude Elferink et al, 2001 ; Danner et al, 2003 ; Holzer et al, 2003 ; Graves et al, 2006 ; Arasu et al, 2015 ; Blajman et al, 2020 ). Fermentation characteristics, such as production of organic acids, decreasing dynamics of pH, and CO 2 production, depend on medium composition ( Danner et al, 2003 ; Blajman et al, 2020 ).…”