Optimization of Mixed Fermentation Conditions by Mixed Culture of Kefir and Bacillus

Kefir is a kind of fermented milk that is produced by inoculating Kefir grains into milk, mainly consisting of bacteria and yeasts. Bacillus and their metabolites also have found some biotechnological applications in many aspects. The aim of the present study was to evaluate the mixed fermentation conditions by kefir and Bacillus. The results showed that kefir and Bacillus could be mixed fermentation, the suggested optimum fermentation conditions are the following: inoculum size was 4 mL of mixed fermentation agent for per 100 mL medium, the ratio to kefir and Bacillus is 2:1, fermentation temperature of 28 °C and fermentation time of 20 h. Under the optimum fermentation conditions, the viable cell counts of Lactic acid bacteria, yeast and Bacillus could above 1.0×1011, 4.0×1010, and 2.0×109CFU/mL respectively. After freeze-dried, by adding 10 % ( w/v ) skim milk, 3 % ( w/v ) glycerinum, 3 % trehalose and 1 % ( w/v ) Monosodium glutamate as for cryoprotectant, the viable cell counts could still above 107CFU/mL after 6 month.

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Optimization of the growth of Lactobacillus in skim milk added with green banana flour and determination functional properties

Nutrition & Food Science ◽

10.1108/nfs-03-2018-0098 ◽

2019 ◽

Vol 49 (2) ◽

pp. 249-261 ◽

Cited By ~ 1

Author(s):

Marli Busanello ◽

Marsilvio Lima De Moraes Filho ◽

Karla Bigetti Guergoletto ◽

Sandra Garcia

Keyword(s):

Antioxidant Activity ◽

Proteolytic Activity ◽

Inhibitory Activity ◽

Skim Milk ◽

Fermented Milk ◽

Lactobacillus Helveticus ◽

Fermentation Time ◽

Content Type ◽

Banana Flour ◽

Green Banana

Purpose This paper aims to study the effect of addition of green banana flour (GBF) in skim milk, provides a nutritional and functional contribution to this matrix when added. They have biological compounds like resistant starch, phenolic compounds, antioxidant compounds and others. The skim milk containing 1.08 per cent of GBF was chosen after a central composite rotational design and response surface methodology. The response variable was the growth of Lactobacillus plantarum (LP) and Lactobacillus helveticus (LH). Design/methodology/approach During the fermentation process, the antioxidant activity, plasmid DNA protection capacity, proteolytic activity and inhibitory activity of angiotensin-converting enzyme (ACE) of the fermented milk was determined. Findings All variables were influenced by the fermentation time. The antioxidant activity evaluated by the ABTS radical presented values of 0.83 ± 0.04 µM Trolox.mL−1 and 0.79 ± 0.02 µM Trolox.mL−1, respectively, for the fermented LP and LH. The extracts fermented by L. plantarum and L. helveticus were able to inhibit the oxidation of plasmidial DNA. The proteolytic activity was higher in the fermented with LH (1.16 ± 0.03) than in the fermented with LP (0.71 ± 0.02). The ACE inhibitory activity was higher in the fermented LH (59.01 per cent) than in the fermented LP (54.45 per cent). Originality/value Fermented milk with 1.08 per cent GBF presented positive results in the analyzed variables and could be studied commercially as a functional food alternative.

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The antimutagenic properties of a polysaccharide produced by Bifidobacterium longum and its cultured milk against some heterocyclic amines

Canadian Journal of Microbiology ◽

10.1139/w98-103 ◽

1998 ◽

Vol 44 (11) ◽

pp. 1029-1036 ◽

Cited By ~ 23

Author(s):

O Sreekumar ◽

A Hosono

Keyword(s):

Bifidobacterium Longum ◽

Skim Milk ◽

Fermented Milk ◽

Heterocyclic Amines ◽

Lag Phase ◽

Fermentation Time ◽

Dependent Inhibition ◽

Dependent Strain ◽

Crude Polysaccharide ◽

Dose Dependent

The antimutagenicity and fermentation pattern of three Bifidobacterium longum strains (B. longum, B. longum PS+, and B. longum PS-) in skim milk were studied. The increase in fermentation time significantly increased antimutagenicity with all strains tested against the mutagenicity of both 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) and 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) in an Ames-like test using streptomycin-dependent strain SD510 of Salmonella typhimurium TA98. Bifidobacterium longum PS+, a polysaccharide-producing strain, had a longer lag phase but showed the highest inhibition percentage against both mutagens tested. The viability of B. longum PS+ cells was not affected by the low pH of 4.1, probably owing to the protection offered by the polysaccharide produced. The antimutagenicity of the fermented milk against Trp-P-1 was dose dependent. The strains were also able to bind with different amino acid pyrolysates, and B. longum showed the highest binding. Acetone extracts of fermented skim milk dissolved in water showed less antimutagenicity than extracts dissolved in dimethylsulfoxide. The isolated crude polysaccharide from B. longum PS+ showed a dose-dependent inhibition of the mutagenicity of Trp-P-1. Thus, we conclude that the polysaccharide of B. longum PS+ can be used as an antimutagen.Key words: Bifidobacterium longum, polysaccharides, fermented milk, heterocyclic amines.

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On the Optimization of Fermentation Conditions for Enhanced Bioethanol Yields from Starchy Biowaste via Yeast Co-Cultures

Sustainability ◽

10.3390/su13041890 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1890

Author(s):

Mohamed Hashem ◽

Saad A. Alamri ◽

Tahani A. Y. Asseri ◽

Yasser S. Mostafa ◽

Gerasimos Lyberatos ◽

...

Keyword(s):

Ethanol Yield ◽

Inoculum Size ◽

Small Scale ◽

Bioethanol Production ◽

Fermentation Time ◽

Fermentation Conditions ◽

Batch Cultures ◽

Yeast Strains ◽

Optimization Of Fermentation ◽

The Impact

The present study aims to assess the impact of the type of yeast consortium used during bioethanol production from starchy biowastes and to determine the optimal fermentation conditions for enhanced bioethanol production. Three different yeast strains, Saccharomyces cerevisiae, Pichia barkeri, and Candida intermedia were used in mono- and co-cultures with pretreated waste-rice as substrate. The optimization of fermentation conditions i.e., fermentation time, temperature, pH, and inoculum size, was investigated in small-scale batch cultures and subsequently, the optimal conditions were applied for scaling-up and validation of the process in a 7-L fermenter. It was shown that co-culturing of yeasts either in couples or triples significantly enhanced the fermentation efficiency of the process, with ethanol yield reaching 167.80 ± 0.49 g/kg of biowaste during experiments in the fermenter.

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Development of a Quantitative Competitive PCR Assay for Detection and Quantification of Escherichia coliO157:H7 Cells

Applied and Environmental Microbiology ◽

10.1128/aem.67.7.3291-3294.2001 ◽

2001 ◽

Vol 67 (7) ◽

pp. 3291-3294 ◽

Cited By ~ 26

Author(s):

Wenli Li ◽

Mary Anne Drake

Keyword(s):

Pathogenic Bacteria ◽

Skim Milk ◽

Viable Cell ◽

Quantitative Detection ◽

Competitive Pcr ◽

Pcr Assay ◽

E Coli ◽

Cell Counts ◽

Cell Densities ◽

Detection And Quantification

ABSTRACT A quantitative competitive PCR (QC-PCR) assay was developed to detect and quantify Escherichia coli O157:H7 cells. From 103 to 108 CFU of E. coli O157:H7 cells/ml was quantified in broth or skim milk, and cell densities predicted by QC-PCR were highly related to viable cell counts (r 2 = 0.99 and 0.93, respectively). QC-PCR has potential for quantitative detection of pathogenic bacteria in foods.

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Assay of Enterocin AS-48 for Inhibition of Foodborne Pathogens in Desserts

Journal of Food Protection ◽

10.4315/0362-028x-72.8.1654 ◽

2009 ◽

Vol 72 (8) ◽

pp. 1654-1659 ◽

Cited By ~ 11

Author(s):

PILAR MARTINEZ VIEDMA ◽

HIKMATE ABRIOUEL ◽

NABIL BEN OMAR ◽

ROSARIO LUCAS LÓPEZ ◽

EVA VALDIVIA ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Listeria Monocytogenes ◽

Bacillus Cereus ◽

Proteolytic Activity ◽

Foodborne Pathogens ◽

Viable Cell ◽

Inoculum Size ◽

Cell Counts

Enterocin AS-48 was tested against Staphylococcus aureus, Bacillus cereus, and Listeria monocytogenes in different kinds of desserts. The highest activity against S. aureus was detected in baker cream. However, in yogurt-type soy-based desserts and in gelatin pudding, AS-48 (175 arbitrary units [AU]/g) reduced viable cell counts of S. aureus by only 1.5 to 1.8 log units at most. The efficacy of AS-48 in puddings greatly depended on inoculum size, and viable S. aureus counts decreased below detection levels within 24 h for inocula lower than 4 to 5.5 log CFU/g. For L. monocytogenes, bacteriocin concentrations of 52.5 to 87.5 AU/g reduced viable counts below detection levels and avoided regrowth of survivors. The lowest activity was detected in yogurt-type desserts. For B. cereus, viable cell counts were reduced below detection levels for bacteriocin concentrations of 52.5 AU/g in instant pudding without soy or by 175 AU/g in the soy pudding. In gelatin pudding, AS-48 (175 AU/g) reduced viable cell counts of B. cereus below detection levels after 8 h at 10°C or after 48 h at 22°C. Bacteriocin addition also inhibited gelatin liquefaction caused by the proteolytic activity of B. cereus.

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Identification and Effects of Skim Milk-Derived Bioactive Antihypertensive Peptides

Biologics ◽

10.3390/biologics2010001 ◽

2021 ◽

Vol 2 (1) ◽

pp. 1-14

Author(s):

Fatah B. Ahtesh ◽

Lily Stojanovska ◽

Vijay Mishra ◽

Osaana Donkor ◽

Jack Feehan ◽

...

Keyword(s):

Blood Pressure ◽

Bioactive Peptides ◽

Milk Powder ◽

Skim Milk ◽

Fermented Milk ◽

Skim Milk Powder ◽

Angiotensin Converting Enzyme Inhibition ◽

Blood Pressure Lowering Effect ◽

Spontaneously Hypertensive ◽

Freeze Dried

Bioactive peptides are generated during milk fermentation or enzymatic hydrolysis. Lactobacillus (L) helveticus is commonly used to produce some types of fermented milk products. Fermented milk derived bioactive peptides are known to be beneficial in human health. Anti-hypertensive peptides play a dual role in the regulation of hypertension through the production of the vasoconstrictor angiotensin II and its inactivation of the vasodilator bradykinin. MALDI MS/MS, nano-LC/MS/MS and RP-HPLC were used to isolate peptides showing angiotensin converting enzyme inhibition (ACE-I) from 12% fermented skim milk using a combination of L. helveticus and Flavourzyme®. The fermentation procedure facilitated the identification of 133 anti-hypertensive peptides and 75% short chain amino acids, and the three with the highest ACE-I activity reduced blood pressure in a rat model of hypertension. The freeze- dried extract was supplemented in rodent chow. In this study 14-week-old male spontaneously hypertensive rats were fed for 10 weeks with the identified peptides added to chow and compared to controls supplemented with skim milk powder. Blood pressure (BP) decreased significantly (p < 0.05) from 6 to 10 weeks of FS groups (120/65 mmHg) compared with the NFS control groups, where the BP increased significantly (220/150 mmHg) (p < 0.05). The F6 fraction provided bioactive peptides with stronger antihypertensive properties than other fractions. Skim milk fermented by L. helveticus and Flavourzyme® generates several bioactive peptides which have a blood pressure lowering effect in hypertensive disease.

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Preparation of Indigenous Lactic Acid Bacteria Starter Cultures for Large Scale Production of Fermented Milk

Digital Press Life Sciences ◽

10.29037/digitalpress.22327 ◽

2020 ◽

Vol 2 ◽

pp. 00010

Author(s):

Tyas Utami ◽

Amaralda Cindarbhumi ◽

Marcella C. Khuangga ◽

Endang S. Rahayu ◽

Muhammad Nur Cahyanto ◽

...

Keyword(s):

Lactic Acid ◽

Lactic Acid Bacteria ◽

Growth Medium ◽

Large Scale ◽

Starter Culture ◽

Viable Cell ◽

Fermented Milk ◽

Starter Cultures ◽

Mixed Cultures ◽

Freeze Dried

<div>Lactobacillus plantarum Dad 13, an indigenous probiotic was examined its ability to be used as a single starter culture or mixed cultures with Streptococcus thermophilus Dad 11 for milk fermentation. Both cultures were isolated from dadih, a traditional fermented buffalo milk. The purposes of this study were to produce indigenous lactic acid bacteria starter cultures using halal growth medium and evaluate their application on large scale fermented milk production. The halal medium was developed using natural compounds such as sucrose, meat peptone, mung bean sprout extract, tomato extract, and young coconut water. Meat peptone was prepared by hydrolysis of halal meat using crude bromelain. Lactic acid bacteria were grown in the halal growth medium then harvested, frozen and freeze-dried. A single freeze-dried starter culture of L. plantarum Dad 13 and frozen mixed cultures of L. plantarum Dad 13 and S. thermophilus Dad 11 were prepared for production of fermented milk drink and yogurt respectively in industrial scale. The growth of these lactic acid bacteria in halal growth medium increased the viable cell to two log cycles (109 CFU/mL) for L. plantarum Dad 13 and one log cycle for S. thermophilus Dad 11 (108 CFU/mL), respectively. The viable cell of freeze-dried L. plantarum Dad 13 and S. thermophilus Dad 11 were 7.57 x 1010 CFU/g and 6.35 x 109 CFU/g, respectively. The number of viable cells and pH of both fermented milk drink and yogurt products was relatively stable to 107 CFU/mL and 108 CFU/mL, respectively during cold storage for four to six weeks. The sensory characteristics of the products were comparable to the ones using commercial starter cultures. It can be concluded that these indigenous starter cultures can be applied for the production of probiotic fermented milk.</div>

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High Pressure Homogenization versus Heat Treatment: Effect on Survival, Growth, and Metabolism of Dairy Leuconostoc Strains

Journal of Food Protection ◽

10.4315/0362-028x.jfp-12-013 ◽

2012 ◽

Vol 75 (9) ◽

pp. 1634-1641 ◽

Cited By ~ 2

Author(s):

D. M. GUGLIELMOTTI ◽

F. PATRIGNANI ◽

R. LANCIOTTI ◽

M. E. GUERZONI ◽

J. A. REINHEIMER ◽

...

Keyword(s):

Heat Treatment ◽

High Pressure ◽

Skim Milk ◽

Viable Cell ◽

Inhibitory Effect ◽

Microbial Inactivation ◽

High Pressure Homogenization ◽

Cell Counts ◽

Total Destruction ◽

Aldehydes And Ketones

The effect of high pressure homogenization (HPH) with respect to a traditional heat treatment on the inactivation, growth at 8°C after treatments, and volatile profile of adventitious Leuconostoc strains isolated from Cremoso Argentino spoiled cheeses and ingredients used for their manufacture was evaluated. Most Leuconostoc strains revealed elevated resistance to HPH (eight passes, 100 MPa), especially when resuspended in skim milk. Heat treatment was more efficient than HPH in inactivating Leuconostoc cells at the three initial levels tested. The levels of alcohols and sulfur compounds increased during incubation at 8°C in HPH-treated samples, while the highest amounts of aldehydes and ketones characterized were in heated samples. Leuconostoc cells resuspended in skim milk and subjected to one single-pass HPH treatment using an industrial-scale machine showed remarkable reductions in viable cell counts only when 300 and 400 MPa were applied. However, the cell counts of treated samples rose rapidly after only 5 days of storage at 8°C. The Leuconostoc strains tested in this work were highly resistant to the inactivation treatments applied. Neither HPH nor heat treatment assured their total destruction, even though they were more sensitive to the thermal treatment. To enhance the inhibitory effect on Leuconostoc cells, HPH should be combined with a mild heat treatment, which in addition to efficient microbial inactivation, could allow maximal retention of the physicochemical properties of the product.

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