Mixed Starter Research Articles

Functional UF-low and full-fat Labneh supplemented with Oats (Avena sativa L.) powder and probiotic bacteria

In this study the effect of using ultrafiltration (UF) processes, incorporating Oats (Avena sativa L.) powder (0, 1, 2%) and probiotic bacteria on the properties and nutritional value of synbiotic functional UF-low and full-fat Labneh was investigated. Mixed starter of Lactobacillus casei and Lactobacillus paracasei (1:1) was added (2%) and used as probiotic bacteria. The samples of both controls and all resultant synbiotic Labneh treatments were analyzed for gross chemical composition, microbiological and sensory attributes during 35 and 21 days, respectively at 5 °C. Also nutritional values were determined and calculated in all fresh samples. Lactose content and pH values were decreased during the storage period in all Labneh samples. Results showed that all low-fat Labneh treatments can provide human with high protein amount daily value (20% DV or more) while, low-fat UF-Labneh supplemented with 2% Oats recorded the highest daily values of protein (24.52%). Moreover, the results indicated that adding 2% of Oats to the UF-low fat Labneh, improve sensory parameters, motivate the numbers of probiotic bacteria and extended the shelf life. Moreover, all Labneh treatments were free from coliform group through all storage periods. The highest sensory total score was observed for UF-low fat Labneh at 7 days of storage and UF-low fat Labneh supplemented with 1% Oats at 28 days of storage. Finally, in this study using UF-technique and adding Oats powder in making Labneh, improved the nutritional value as it increased protein, %DV and fiber contents and decreasing lactose content which will be suitable for people who suffering from lactose intolerance. Also using the probiotic bacteria which produce bacteriocins; minimize the fungi and psychrophilic bacterial counts.

Anti-inflammation and gut microbiota regulation properties of fatty acids derived from fermented milk in mice with dextran sulfate sodium-induced colitis.

The by-products of milk fermentation by lactic acid bacteria provide potential health benefits to the balance of host intestinal microflora. In this study, the anti-inflammatory properties of fatty acids from monoculture-strain (Lactiplantibacillusplantarum A3) and multiple-strain (Streptococcus thermophilus, Lactobacillus bulgaricus, and L. plantarum A3 1:1:2) fermented milk were evaluated in a mouse model of dextran sulfate sodium-induced colitis, and the gut microbiota regulation properties of the fatty acids were also investigated. Results showed that fatty acids can attenuate the inflammatory response by inhibiting the expression of inflammatory factors IL-6 and tumor necrosis factor-α, and blocking the phosphorylation of the JNK in MAPK signal pathway. In addition, the relative abundance of the taxa Akkermansia and Lactobacillus were both enriched after the fatty acid intervention. This finding suggests that fatty acids from the milk fermentation with mixed lactic acid bacteria starters can reduce the severity of dextran sulfate sodium-induced colitis and enhance the abundance of the probiotics in the mice intestinal tract.

Peptidomics insights into the interplay between the pre-digestion effect of mixed starters and the digestive pattern of sausage proteins

This work investigated the influence of mixed starters (Lactobacillus plantarum CD101 and Staphylococcus simulans NJ201) on the digestive pattern of dry fermented sausage proteins. The addition of starters resulted in a higher degree of proteolysis and looser protein conformation as evidenced by the decreased carbonyl content and electrophoresis bands intensity of myosin heavy chain (MHC) and actin, increased sulfhydryl content and surface hydrophobicity, and transformation of protein secondary structure from α-helix to β-sheet and β-turn. These changes induced by the starters acted as a “pre-digestion” step and improved the digestive pattern of sausage protein. The most remarkable improvement in gastric (33.98%–49.46%) and whole gastrointestinal digestibility (87.41%–94.57%) was observed on sausages of day 21. Comparative peptidomics analysis during digestion revealed that the digested peptides of the inoculated sample were more widely distributed throughout the 3D structure of the sausage proteins, namely, myoglobin, MHC, and creatine kinase M-type. More peptides were degraded in the rod region (780–1933) of MHC. The region was possibly expanded by starters. New bioactive peptides, including MNVKHWPWMK, FFL, and LLF, were released from the MHC and actin altered by the starters. This work highlighted the application of mixed starters as a potential tool to enhance the nutrition of fermented sausage.

Improving the safety and quality of Roucha using amine-degrading lactic acid bacteria starters

Biogenic amines (BA) are often present at high concentrations in fermented meat and cause foodborne illness. The aim of this work was to screen amine-degrading starters for Roucha (a fermented meat) to improve product safety and quality. Firstly, Weissella viridescens F2 and Lactiplantibacillus plantarum His6 with multi-copper oxidase activity and high degradation rates towards histamine and tyramine were selected as single or mixed starters. Additionally, the effect of starters on bacterial community succession, acid production, BA accumulation, free amino acid profiles, and volatile compound profiles were evaluated during the fermentation of Roucha. Results indicated that all starters could effectively reduce the accumulation of BA in Roucha. At the end of fermentation, Lpb. plantarum His6 as a single starter reduced the histamine level (38.15 %), while mixed starters (Lpb. plantarum His6 + W. viridescens F2) possessed a high tyramine-reduction rate (54.95 %) and total BA-reduction rate (46.64 %). Bacterial succession analysis revealed that starters could help establish the dominance of lactobacilli or Weissella quickly, which contributed to the direct degradation of BA and inhibited the growth of amine-producing bacteria. Furthermore, Lpb. plantarum His6 could promote the accumulation of essential amino acids (leucine, phenylalanine, threonine, isoleucine), sweet and umami amino acids (glycine, threonine, glutamate), and volatile compounds of good odor, indicating that this strain greatly contributed to the development of good taste and aroma characteristics in Roucha. Overall, this work shows that the application of amine-degrading starters is an effective strategy to reduce the BA accumulation and improve the quality of Roucha. Thus, these findings can provide foundations for the industrial production of Roucha.

Impact of axenic and mixed starter cultures on metabolomic and sensory profiles of ripened Italian salami

In this work, the synergistic/antagonistic impact of glucose and mixed starter cultures, namely Latilactobacillus sakei, Pediococcus pentosaceus, and Staphylococcus xylosus, was evaluated in Italian salami in terms of metabolomics and sensory profiles. As expected, Salami manufactured with 0.5 % glucose exhibited a substantial pH drop, showing values close to 5 at 12 days of ripening. Metabolomics revealed 1841 metabolites, mainly belonging to amino acids, peptides, glycerolipids, and nucleic acids, showing a greater hierarchical role of glucose addition when compared with inoculated microbial starters. Distinct metabolomic fingerprints could be observed across treatments, mainly concerning glutamyl peptides like gamma-glutamyl-glutamate (related to the kokumi taste), biogenic amines (spermine), and lipid oxidation products (i.e., the oxylipin 13S-hydroperoxylinolenic acid). Such differences may drive the differences in sensory profiles recorded among treatments. These findings indicate the need to select ad-hoc starter cultures to improve the safety, quality, and sensory traits of salami.

Effect of inoculating mixed starter cultures of Lactobacillus and Staphylococcus on bacterial communities and volatile flavor in fermented sausages

The objective of this study was to explore the effects of the inoculation of mixed starter cultures of Lactobacillus and Staphylococcus (labeled L-S) on microbial community and flavor in fermented sausages during the ripening process. Culture-dependent (colony count) and culture-independent (high-throughput sequencing) methods were employed to evaluate bacterial communities. Volatile compounds were identified by gas chromatography–mass spectrometry, and the results were analyzed by principal component analysis (PCA). The identified bacteria with high relative abundance included Lactobacillus and Pediococcus, and the relative abundances of Leuconostoc and Weissella in fermented sausages were remarkably decreased at the end of the ripening process. At the end of ripening, 2-nonenal, tetradecanal, ethylstearate and terpinyl acetate played substantial roles in the flavor development of the L-S fermented sausages. Sensory evaluation showed a high score in the L-S fermented sausages. Sausages can be inoculated with L-S starter culture to improve the safety and flavor of meat products.

Probiotic Yoghurt Made from Milk of Ewes Fed a Diet Supplemented with Spirulina platensis or Fish Oil

PurposeYoghurt is a widely consumed dairy product around the world. It has healing properties and characteristics that are important for human health. Our goal was to see how using ewes' milk fed Spirulina platensis (SP) or fish oil (FO)-supplemented diets affected the chemical, physical, and nutritional properties of yoghurt, as well as the activity and survival of starter and probiotic bacteria during storage.MethodsThe collected milk from each ewe group was preheated to 65 °C and homogenized in a laboratory homogenizer, then heated to 90 °C for 5 min, cooled to 42 °C, and divided into two equal portions. The first portion was inoculated with 2.0% mixed starter culture (Lactobacillus bulgaricus and Streptococcus thermophilus, 1:1), whereas the second was inoculated with 2% mixed starter culture and 1% Bifidobacterium longum as a probiotic bacteria.ResultsSP yoghurt had the highest levels of short chain-FA, medium chain-FA, mostly C10:0, and long chain-FA, namely C16:0, C18:2 and the lowest levels of C18:0 and C18:1, followed by FO yoghurt. The addition of SP or FO to ewes' diets resulted in yoghurt with higher viable counts of L. bulgaricus and S. thermophilus, which were still >107 cfu/g at the end of storage, as well as a higher level of acetaldehyde content (P<0.05) as a flavor compound, than the control (C) yoghurt. The viscosity of SP yoghurt was higher than that of FO and C yoghurt; the difference was not significant. The addition of B. longum, a probiotic bacteria, to all yoghurt samples, improved antioxidant activities, particularly against ABTS• radicals, but reduced SP yoghurt viscosity. When B. longum was added, acetaldehyde content increased from 39.91, 90.47, and 129.31 μmol/100g in C, FA, and SP yoghurts to 46.67, 135.55, and 144.1 μmol/100g in probiotic C, FA, and SP yoghurts, respectively. There was no significant difference in sensory qualities among all the yoghurt samples during all storage periods.ConclusionsSupplementing the ewes' diets with Spirulina platensis or fish oil can change the fatty acid composition of the resulting yoghurt. The starter culture's activity, flavor compounds, and some chemical, physical, and antioxidant properties of milk produced from these diets can all be improved, particularly in yoghurt treated with probiotic bacteria (B. longum).

Improvement of Taste Enhancer Condiment Processing and Safety Using Marinade and bio-preservation of Cassava Fish (Pseudotolithus Sp)

ABSTRACT This study aims to improve Lanhouin production using marinade and mixed starter cultures of Lactobacillus plantarum and Staphylococcus xylosus as bio-preservation agents. The microbial and the physico-chemical properties of fish products obtained were characterized according to standard methods. Both combined strains developed an excellent ability to ferment fish flesh. The samples inoculated with the starter cultures had low pH value (4.7) and high level of lactic acid bacteria (LAB) (6.2 Log CFU/g) and coagulase negative Staphylococcus (CNS) (5.4 Log CFU/g) than the control samples. After 90 days of storage, the ratio of total viable count (TVC) and LAB count in the final dried products was equal to 100, as recommended by the “Federation of Trade and Distribution Companies” (FCD). Moreover, no pathogens were detected in the analyzed samples, and yeast and molds counts were less than 1 Log CFU/g.

Impact of Saccharomyces cerevisiae and non-Saccharomyces yeasts to improve traditional sparkling wines production

In this study the effect of a co-inoculum of S. cerevisiae (F6789) with Torulaspora delbrueckii (TB1) or Starmerella bacillaris (SB48) on the oenological and aroma characteristics of sparkling wines obtained with the Champenoise method was investigated. The autolytic outcome and the sensory profile of sparkling wines were also evaluated. The secondary fermentations were completed by all mixed and single starter cultures with the only exception of those guided by Starm.bacillaris. Sparkling wines produced with S. cerevisiae F6789+Starm.bacillaris SB48 showed the highest amounts of glycerol (6.51 g/L). The best autolytic potential was observed in sparkling wines produced with +Starm.bacillaris (81.98 mg leucin/L) and S. cerevisiae+T. delbrueckii (79.03 mg leucin/L). The lowest value was observed for sparkling wines obtained with S. cerevisiae F6789 (53.96 mg leucin/L). Sparkling wines showed different aroma and sensory profiles. Esters were mainly present in sparkling wines obtained with S. cerevisiae F6789 (88.09 mg/L) followed by those obtained with S. cerevisiae+T. delbrueckii (87.20 mg/L), S. cerevisiae +Starm.bacillaris (81.93 mg/L). The content of esters decreased over time, and that might be related to the adsorption on lees and chemical hydrolysis. The highest concentrations of higher alcohols were found in sparkling wines produced with S. cerevisiae+T. delbrueckii (27.50 mg/L). Sparkling wines obtained with S. cerevisiae +Starm.bacillaris were well differentiated from the others due to their high score for the descriptor for spicy, bread crust, freshness and floral.Tailored strains with different autolytic potential might represent an interesting strategy to improve traditional sparkling wine production and favour their differentiation.

Impact of Starmerella bacillaris and Zygosaccharomyces bailii on ethanol reduction and Saccharomyces cerevisiae metabolism during mixed wine fermentations

The bulk of grape juice fermentation is carried out by the yeast Saccharomyces cerevisiae, but non-Saccharomyces yeasts can modulate many sensorial aspects of the final products in ways not well understood. In this study, some of such non-conventional yeasts were screened as mixed starter cultures in a defined growth medium in both simultaneous and sequential inoculations. One strain of Starmerella bacillaris and another of Zygosaccharomyces bailii were chosen by their distinct phenotypic footprint and their ability to reduce ethanol levels at the end of fermentation. S. bacillaris losses viability strongly at the end of mixed fermentations, while Z. bailii remains viable. S. cerevisiae viability was unchanged by the presence of the other yeasts. Physiological characterization of both strains indicates that S. bacillaris behavior is overall more different from S. cerevisiae than Z. bailii. In addition, S. cerevisiae transcriptome changes to a bigger degree in the presence of S. bacillaris in comparison to mixed fermentation with Z. bailii. S. bacillaris induces the translation machinery and repress vesicular transport. Both non-Saccharomyces yeasts induce S. cerevisiae glycolytic genes, and that may be related to ethanol lowering, but some aspects of carbon-related mechanisms are specific for each strain. Z. bailii presence increases the stress-related polysaccharides trehalose and glycogen, while S. bacillaris induces gluconeogenesis genes.

Effect of starter cultures and spices on physicochemical properties and microbial communities of fermented fish (Suanyu) after fermentation and storage

Suanyu is one of the traditional Chinese fermented fish products with a pleasant flavor. The present study sought to evaluate the effects of starter cultures and spices on the physicochemical properties and microbial flora of Suanyu after fermentation and storage. The results indicated that fermentation with mixed starter cultures could lower the pH and inhibit TVB-N formation in Suanyu after fermentation and during storage. Moreover, inoculation of starter cultures could promote free amino acids production during storage. Additionally, inoculation of mixed starter cultures and spices mixture could effectively inhibit the formation of most biogenic amines in Suanyu, revealing the significant role of mixed starter cultures. Staphylococcus, Macrococcus, and Lactobacillus were the core microbial genus in Suanyu. The inoculation of starter cultures could inhibit Enteroccoccus and other microorganisms, while spices introduced Bacillus into Suanyu. The study results provide a theoretical basis for the industrial production and storage of Suanyu.

Rheological, microbiological and sensory properties of fermented khainak milk fermented with different starter cultures

A comparison study of the fermentation process of khainak (a hybrid of yak and cattle) and cow milk with commercial yoghurt (thermophilic), quark (mesophilic and mixed) starter cultures was conducted to find suitable starters using modern rheological, microbiological, and sensory methods. Lactic acid accumulation dynamic during the fermentation process of khainak milk with yoghurt starters was faster but did not differ from cow milk. The gel strength of the fermented khainak milk (206.3–447.2 Pa) was higher than that of cow milk (40–158 Pa). The total viable bacterial counts of all samples were not significantly different between the samples (8.43–9.46 log cfu mL−1). The improved whey separation in fermented khainak milk samples with mesophilic and mixed starter cultures suggests these starter cultures for the production of quark and cheese from khainak milk.

Effect of Chinese Baijiu coupled with a ternary mixed starter on the flavor component structure of Chinese Dongbei suancai

Effect of Chinese Baijiu coupled with a ternary mixed starter on the flavor component structure of Chinese Dongbei suancai

Evaluation of acha flour in the production of gluten‐free sourdough cookies

SummaryEmploying biotechnology processing in the manufacturing of baked goods with underutilised gluten‐free cereals is deserving of marked interest to get new niche products. This study aims at determining the influence of sourdough made with starter cultures on the nutritional and sensory characteristics of cookies produced with acha flour. Sourdough containing lactic acid bacteria and yeast starters were added as ingredients for making acha‐based cookies. Sourdough increased the spread ratio of the cookies. Fructilactobacillus fructivorans and Candida tropicalis as mixed starters gave the highest values (6.52 ± 0.06 and 2.21 ± 0.27, respectively) for crude protein and ash. Sourdough addition and the type of starter culture used for the fermentation influenced the mineral composition of cookies (P &lt; 0.05). The most overall acceptable was SBTC, made with only C. tropicalis sourdough. Utilisation of acha with sourdough addition is recommended for making cookies with improved qualities and promoting the locally grown cereal for potential health benefits.

Technological characterization and molecular identification of defined protective starter cultures for fermentation of traditional Rayeb made from camel's milk

AbstractCamel milk isolates of lactic acid bacteria were characterized to develop defined starter cultures that could be used for the production of standardized Egyptian Rayeb fermented milk. The isolates have shown a wide diversity of Technological characteristics and antimicrobial activity. Interesting isolates were genetically identified at the species level. Two mixed culture starters composed of Lactiplantibacillus plantarum (FFNL146 and FFNL159) and Lactococcus lactis (FFNL1926 and FFNL2005) along with Leuconostoc pseudomesenteroides FFNL2374 were used in the production of Rayeb from camel milk, cow milk, and their mixture and stored for 14 days under refrigeration. Equally mixed camel and cow milk fermented with both starters had the best results of organoleptic attributes and physicochemical properties compared to samples made of camel milk. This is the first study to present two mixed starter cultures for Rayeb manufacturing. The success of these defined starter cultures will potentially enhance the safety and quality of the Rayeb industry in Egypt.

Angiotensin‐converting enzyme (ACE) inhibitory peptides from fermented sausages inoculated with Lactobacillus plantarum CD101 and Staphylococcus simulans NJ201

AbstractNatural ACE inhibitory peptides derived from food are considered to be an effective supplement for lowering blood pressure. This study investigated the effects of Lactobacillus plantarum CD101 and Staphylococcus simulans NJ201 on proteolysis and the sequence composition of ACE inhibitory peptides in fermented sausages. The ACE inhibitory activity of the inoculated group reached the maximum values on day 35 during the production of fermented sausages. A more positive effect in the hydrolysis of the sarcoplasmic and myofibrillar protein was observed in the inoculated group through sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS‐PAGE). The free amino acid content of the inoculated group was 865.21 ± 12.55 mg/100 g, which was significantly higher (P &lt; 0.05) than that of the control group. The molecular weight distribution showed a significant increase (P &lt; 0.05) in peptides with a molecular weight less than 1 kDa in the inoculated group. A total of thirty‐four peptides with high hydrophobicity were identified by liquid chromatograph‐mass spectrometer/mass spectrometer (LC–MS/MS). Furthermore, the peptides were isolated and purified using gel filtration chromatography (GFC) and reversed‐phased high‐performance liquid chromatography (RP‐HPLC). Eleven novel peptides were identified by Nano‐LC‐ESI‐MS/MS, in which VALSLSRP with X‐Pro structure exhibited the highest ACE inhibition rate (75.36 ± 2.45%). These results indicated that mixed starters are conducive to protein degradation and the formation of peptides with high ACE inhibitory activity, especially peptides less than 1 kDa, and could be used as a functional material for antihypertensive drugs.

Date Seeds Flour Used as Value-Added Ingredient for Wheat Sourdough Bread: An Example of Sustainable Bio-Recycling.

Our study proposed date seeds flour (DSF) as an innovative ingredient for sourdough bread production through sustainable bio-recycling. We isolated autochthonous lactic acid bacteria and yeasts from DSF and DSF-derived doughs to build up a reservoir of strains from which to select starters ensuring rapid adaptation and high ecological fitness. The screening based on pro-technological criteria led to the formulation of a mixed starter consisting of Leuconostoc mesenteroides, Lactiplantibacillus plantarum, and Saccharomyces cerevisiae strains, which allowed obtaining a mature type I sourdough after consecutive refreshments, in which an aliquot of the durum wheat flour (DWF) was replaced by DSF. The resulting DSF sourdough and bread underwent an integrated characterization. Sourdough biotechnology was confirmed as a suitable procedure to improve some functional and sensory properties of DWF/DSF mixture formulation. The radical scavenging activity increased due to the consistent release of free phenolics. Perceived bitterness and astringency were considerably diminished, likely because of tannin degradation.

Effects of mixed inoculation of Leuconostoc citreum and Lactobacillus plantarum on suansun (Sour bamboo shoot) fermentation

To study the effects of mixed starter consisted of different fermentative type of lactic acid bacteria (LAB) on the fermentation of suansun, two lactic acid bacteria (Leuconostoc citreum NM-12 and Lactobacillus plantarum L01) isolated from Chinese traditional fermented vegetable were used in the preparation of suansun. The fermentation was carried out at ambient temperature (around 25 °C）for 96 h by inoculating different mixing ratios of LAB (inoculated fermentation) or using natural microbes (natural fermentation). The changes of pH, titratable acid (TA), microbe communities, free sugars, organic acids, nitrite and volatile compounds during fermentation were evaluated. Suansun treated with high Leuconostoc citreum ratio inoculation exhibited a quickly change in pH and TA, resulting from the rapid increase in the number of viable cells, at the early stage of fermentation and produced more mannitol (0.12–0.46 mg/mL) and acetic acid (0.93–3.56 mg/mL). However, Suansun treated with high Lactobacillus plantarum ratio inoculation had lower pH and higher TA at the later stage of fermentation and produced more lactic acid (5.32–7.68 mg/mL). No mannitol was detected in suansun when only Lactobacillus plantarum was inoculated in fermentation. No p-cresol was produced in the inoculated fermentation with mixed starter culture, in addition to the production of ethyl acetate and 2.3-butanedione, which had a positive effect on the flavor of suansun. In summary, this study demonstrated the application value of mixed starter consisted of different fermentative type of LAB. LAB types and mixing ratios greatly affected the types and concentration of metabolites in suansun fermentation.

Isolation of Protease-Producing Bacteria from Shrimp Paste and the Characteristics of Fermenting Catfish Paste

ABSTRACT In this study, six protease-producing halophilic bacterias were isolated from traditional shrimp paste. These strains were used as mixed starter culture to ferment minced catfish muscle. The pH and total volatile base nitrogen in the group with mixed starter cultures (ZB) was lower than that of the group without starter (ZA). The total acidity and the content of amino acid nitrogen and free amino acid in ZB was higher. Additionally, the ZB exhibited a strong umami and fermented flavor. The results show that protease-producing bacteria could improve the flavor and nutritive value of fermented Chinese long-snout catfish by-products.

Potential of lactic acid bacteria to produce functional fermented whey beverage with putative health promoting attributes

A functional fermented whey (FW) beverage was produced by lactic acid bacteria (LAB), Pediococcus pentosaceus ENM104 and Lactiplantibacillus plantarum SPS109. Both strains grew well in MRS medium under aerobic and anaerobic conditions, were susceptible to antibiotics, and showed antibacterial activity via metabolites i.e. organic acids and produced biofilm. A co-culture of the LAB in phosphate-buffered saline reduced heterocyclic aromatic amines, nitrosamines, and biogenic amines, including 2-phenethylamine, putrescine, cadaverine, histamine and tyramine. The cholesterol content of whey fermented for 72 h with the co-culture was 37.60 ± 18.28% lower than the initial content, while γ-aminobutyric acid production increased by 3.91 ± 0.10 μg·mL−1. Angiotensin-converting enzyme (ACE) inhibitory activity increased by 36.07 ± 3.94%. Oxygen radical absorbance capacity (ORAC) increased to 362.06 ± 8.63 nmol TE·mL−1. Putrescine and cadaverine were reduced by 11.84 ± 2.20% and 53.82 ± 2.91%, respectively. This FW inhibited Bacillus cereus TISTR 687, Listeria monocytogenes DMST 17303, and Streptococcus mutans ATCC 25175 with minimum inhibitory concentration (MIC) from 30 to 40% and biofilm inhibitory concentration (BIC) from 35 to 40%. The most sensitive strain was S. mutans, which exhibited 98.52 ± 0.99% biofilm inhibition. Both LAB in a mixed starter showed great potential to produce functional FW through their joint beneficial activities.