Potential Starter Cultures Research Articles

Isolation and Screening of Lactic Acid Bacteria From Sumbawa Buffalo Milk (Bubalus bubalis) as Potential Starter Cultures

The Sumbawa buffalo (Bubalus bubalis) is one of the ruminant livestock in Indonesia that not only contributes to fulfilling meat requirements but also milk. Besides containing nutrients that are very beneficial for human health, buffalo milk is also a potential source of lactic acid bacteria (LAB) with technological and functional properties. Lactic acid bacteria have been utilized as starter cultures in various fermented products. This study aimed to isolate LAB from Sumbawa buffalo milk and to identify the potential isolate as a starter culture. The screening of LAB as a starter culture was based on some technological properties, including proteolytic activity, lipolytic activity, exopolysaccharide (EPS) production, antibacterial activity, antibiotic sensitivity, hemolytic activity, and acidification activity Data were analyzed statistically using one-way ANOVA and Tukey’s post hoc test at a 5% significance level. A total of 21 isolates were isolated from fresh buffalo milk, with a LAB total was 4.7x105 CFU.mL-1. All the isolates were characterized as Gram-positive with cocci-shaped. The SA8 isolate was selected as the most potential candidate as a starter culture because it has fulfilled the criteria such as the highest proteolytic activity, the lowest lipolytic activity, producing EPS, potential antagonistic activity against Bacillus cereus, Escherichia coli, and Salmonella Typhi, and sensitivity to cefazolin, intermediate to erythromycin and cinoxacin, non-pathogen, as well as the most rapid acidification activity. The SA8 isolate was identified as Enterococcus lactis with a similarity level of 99.99% towards strain BT159. This indigenous LAB was a potential starter culture of Sumbawa fermented buffalo milk to increase the diversification of products derived from buffalo milk.

Isolation and characterization of coagulase negative staphylococci with high proteolytic activity from dry fermented sausages as a potential starter culture

Chinese traditional fermented meat products in Guizhou province harbor a unique microbial community owing to particular geographical, environmental, and climatic conditions. In this study, coagulase-negative staphylococci (CNS) with high protease activity were isolated from a Guizhou traditional naturally fermented meat product, i.e., Qianwufu sausages. In addition, the potential of isolated CNS strains to be used as starter cultures in sausage fermentation was evaluated. Culture- and molecular-biology-based methods were employed to isolate and identify CNS. A total of 40 CNS strains could hydrolyze pork meat proteins. In particular, strain QB7 identified as Staphylococcus simulans had the highest proteolytic activity, was resistant to growth in the presence of 6.5 % NaCl and 150 mg/kg of nitrites, and lacked virulence genes, hemolytic, decarboxylase, DNase, and biofilm-forming activities. Subsequently, S. simulans QB7 was used as a starter in sausage fermentation, which led to an increase in competitiveness of dominant bacteria, reduced growth of undesirable bacteria, higher content of total free fatty acids and free amino acids, and lower pH and water activity values. Thus, S. simulans QB7 can potentially be used as a starter to improve the quality and nutritional properties of fermented meat products.

Evaluation and selection of yeasts as potential aroma enhancers for the production of dry-cured ham

Yeasts play a critical role in the flavor formation of dry-cured ham. In this study, 41 yeast isolates from the dry-cured ham at different processing stages were evaluated for their technological properties. Debaryomyces hansenii was the most dominant yeast and has been detected at each phase of dry-cured ham, followed by Candida zeylanoides which was mainly detected in salting phase. Yarrowia bubula and Yarrowia alimentaria were found at the first two-phase of dry-cured ham. All isolates of yeast showed enzymatic activities against milk protein and tributyrin, while only 4 strains displayed proteolytic activity on meat protein. Yeast strains were grown in a meat model medium and volatile compounds were identified. The result showed that inoculated yeast strains could promote the production of volatiles and there were significant differences among strains. D. hansenii S25 showed the highest production of volatile compounds, followed by the strain C. zeylanoides C4. D. hansenii S25 was the highest producer of alcohols showing the highest production of benzeneethanol and 3-(methylthio)-1-propanol. Based on OAV and PLS analysis, D. hansenii S25 was strongly correlated with overall flavor and key volatile compounds of dry-cured ham, which could be selected as potential starter cultures.

Isolation and Identification of Lactococcus lactis and Weissella cibaria Strains from Fermented Beetroot and an Investigation of Their Properties as Potential Starter Cultures and Probiotics.

The presence of certain microorganisms in dairy products or silage is highly desirable. Among them are probiotic strains of lactic acid bacteria (LAB), which show many beneficial features, including antimicrobial properties that support the development of beneficial microflora; in addition, owing to their biochemical activity, they influence the nutritional, dietary, and organoleptic properties of food products. Before being placed on the market, each strain requires separate testing to determine its probiotic properties and effectiveness. The aim of this study was to isolate LAB strains from a pickled beetroot sample that could be used in the dairy industry and with the potential to be considered as a probiotic in the future. Two strains identified using the MALDI technique were selected—Lactococcus lactis and Weissella cibaria. The optimal growth conditions of the strains were determined, and their proteolytic properties were assessed with the use of the o-PA reagent and spectrophotometry. The lipid profile was analyzed using the SALDI (surface-assisted laser desorption/ionization) technique and silver nanoparticles. High-performance liquid chromatography was used to assess the ability of the strains to synthesize beneficial metabolites, such as B vitamins (B2, B3, and B9) or lactic acid, and gas chromatography was used to analyze the substances responsible for organoleptic properties. Moreover, the ability to inhibit the growth of pathogenic strains was also tested in the selected strains. Both tested strains demonstrated the desired properties of starter cultures for future use in functional food production, showing that fermented plant products can serve as valuable potential probiotic sources.

An Evaluation of the Phenotypic Antibiotic Susceptibility of Potential Lactic Acid Bacteria Starter Cultures Isolated From Cambodian Fermented Foods

The development of indigenous starter cultures for producing fermented foods that meet the expectations of Cambodians is necessary to preserve the country’s food supply. In this study, the safety of 46 lactic acid bacteria strains based on the phenotypic antibiotic susceptibility to clinically relevant antibiotics was assessed. The antibiotic susceptibility of 39 lactobacilli and seven pediococci isolated from Cambodian fermented foods to 16 antibiotics was studied according to ISO 10932/IDF 233. The results were interpreted based on the minimal inhibition concentrations obtained, using differently defined breakpoints and concentration distributions as well as data from the scientific literature. Applying only breakpoints, the results demonstrated two Lactiplantibacillus pentosus, three Companilactobacillus futsaii, three Levilactobacillus namurensis and seven Pediococcus pentosaceus strains with acquired resistance. However, considering further information, one Companilactobacillus futsaii, one Limosilactobacillus fermentum and respectively three Lactiplantibacillus pentosus and Levilactobacillus namurensis strains would possess an acquired resistance. The genetic background for the absence of transmissible antibiotic resistances in lactic acid bacteria strains intended for food application must be confirmed by molecular methods for potential starter cultures.

Isolation and characterization of yogurt starter cultures from traditional yogurts and growth kinetics of selected cultures under lab-scale fermentation

The development of new starter cultures is a crucial task for the food industry to meet technological requirements and traditional products are important reservoirs for new starter cultures. In this respect, this study aimed to isolate, identify, and determine the technological characteristics of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus strains originated from traditional yogurt samples. Genotypic discrimination of 200 isolates revealed the presence of distinct 19 S. thermophilus and 11 Lb. delbrueckii subsp. bulgaricus strains as potential starter cultures. Strain-specific properties determined the acidification capacity of the yogurt starter cultures and a higher acidification capacity was observed for S. thermophilus strains compared to Lb. delbrueckii subsp. bulgaricus strains. Proteolytic activity was found between 0.012–0.172 and 0.078–0.406 for S. thermophilus and Lb. delbrueckii subsp. bulgaricus strains, respectively. 4 of S. thermophilus and 3 of Lb. delbrueckii subsp. bulgaricus strains were found resistant to all tested bacteriophages. The antibiotic susceptibility tests of the isolates revealed that a very low antibiotic resistance was observed for the yogurt starter cultures. Finally, the growth kinetics of selected strains were determined and the maximum specific growth rate of selected S. thermophilus and Lb. delbrueckii subsp. bulgaricus was calculated as 0.527 h−1 and 0.589 h−1, respectively.

Characterization of starter cultures and nutritional properties of Pediococcus acidilactici NCDC 252: A potential probiotic of dairy origin

NCDC 252, a potential probiotic, was studied for starter properties. It exhibited proteolytic activity in cow, buffalo, and goat milk and acidified skim milk and cheese by lowering their pH. It survived heat treatment and also in the presence of salt and ethanol. This suggests its fermentation ability for dairy products and beverages. The presence of genes for heavy metal tolerance and vitamins' biosynthesis in its genome suggests its ability for heavy metal detoxification and de novo vitamin synthesis, respectively. HPLC studies confirmed vitamin B12 production. These studies suggest NCDC 252 to be a potential starter culture that can be used for food fortification. Practical applications NCDC 252 possessed α-glucosidase activity. α-glucosidase hydrolyses disaccharides to glucose. The utilization of otherwise indigestible oligosaccharides by humans is an important probiotic attribute. It also exhibited high proteolytic activity and rapid acidification activity. Probiotic strain with proteolytic activity is a new strategy for the production of novel functional foods rich in bioactive peptides. NCDC 252 exhibited high acidification that might contribute to the organoleptic and functional properties of fermented food products. Thus, it should be selected as a part of the starter culture in dairy industries. Production of vitamin B12 is considered an important probiotic characteristic of NCDC 252 for in situ vitamin B12 fortification in the food industry. Production and delivering health-promoting compounds by LAB is a very promising field. The ability of LAB to enrich the food and human body with the aid of producing vitamins and cofactors further enhance the scope of its utilization for medicinal and health applications.

Genotyping of Probiotic Lactobacilli in Nigerian Fermented Condiments for Improved Food Safety

BACKGROUND: Plant-based naturally fermented condiments usually result in poor quality products with various bacteria and fungi contaminants. Previous reports suggested the use of starter cultures from previously fermented condiments in fermentation processes to ensure health-promoting benefits, improved quality, shelf life, and organoleptic properties for the achievement of healthy nutrition, safe, and quality food. AIM: This study aimed to genotype potential lactobacilli from locally fermented condiments for improved food safety. METHODS: The lactobacilli colonies isolated from fermented condiments purchased from food markets in Southwest Nigeria were profiled for probiotic activities, hemolytic activities, antibiotics susceptibility, and inhibitory activities against food pathogens. Interesting probiotic lactobacilli were identified using 16S rRNA gene sequencing and evaluated for phylogenetic relatedness with other globally reported probiotic lactobacilli. RESULTS: Lactobacillus species which expressed significant probiotics, γ-hemolysis, anti-spoilage, and anti-listerial activities (P < 0.05) with tolerable safety profiles were identified as Lactiplantibacillus plajomi YD001 (MW280136), Lactiplantibacillus plantarum YD002 (MW280139), L. plantarum YD003 (MW280137), and Lacticaseibacillus paracasei YD004 (MW280138) possessed 50.75, 50.61, 50.75, and 52.54 mol% DNA G+C contents, respectively. The species clustered into different phylogroups with high clonal relatedness with other potential lactobacilli meta-data (≥96.80%) obtained from the public repository. CONCLUSION: Obtained genotyped Lactobacillus species are potential starter cultures for improved fermentation processes, control of food pathogens, and spoilage organisms.

Changes in bacterial community structure and quality characteristics during fermentation of stinky variegated carp ( Aristichthys nobilis )

Bacterial metabolism greatly affects the quality and flavor of traditional, low-salt fermented fish. We assessed changes in the bacterial community structure and quality characteristics of “stinky” variegated carp (Aristichthys nobilis) during fermentation at 20°C. The total viable count (TVC), firmness, chewiness, tackiness, total volatile base nitrogen (TVB-N) and thiobarbituric acid-reactive substance (TBARS) levels, and relative peak area of volatile compounds significantly (p < .05) increased, while the pH, weight, and elasticity dramatically decreased, during fermentation. The total free amino acid (FAA) content decreased early during fermentation (from 0–2 d) and then significantly (p < .05) increased (from 3–5 d). The levels of flavorful AAs (aspartic acid, glutamate, phenylalanine, tyrosine, alanine, and glycine) increased markedly after 4 d of fermentation. Solid-phase microextraction-gas chromatography–mass spectrometry (SPME-GC–MS) revealed that the levels of ketones, ethers, and nitrogenous compounds increased significantly (p < .05) during fermentation. Illumina MiSeq sequencing identified Plesiomonas as the dominant bacterial genus during fermentation, followed by Aeromonas, Cetobacterium, Vibrio, and Hathewaya. These bacteria may contribute to the flavor and aroma of stinky variegated carp. The association between bacterial succession and the flavor and taste of stinky fish was also discussed. Practical applications Variegated carp could be processed to create stinky fish. In this study, bacterial community structure and quality characteristics analysis were assessed. FAAs and volatile compounds related to flavor and aroma were found. A potential starter culture that could improve the quality of stinky variegated carp was identified. Our findings provide a theoretical basis for the industrial production of fermented stinky fish.

Functional Characterization of khadi Yeasts Isolates for Selection of Starter Cultures.

Yeasts play an important role in spontaneous fermentation of traditional alcoholic beverages. Our previous study revealed that a mixed-consortia of both Saccharomyces and non-Saccharomyces yeasts were responsible for fermentation of khadi, a popular, non-standardized traditional beverage with an immense potential for commercialization in Botswana. Functional characterization of isolated fermenting yeasts from mixed consortia is an indispensable step towards the selection of potential starter cultures for commercialization of khadi. In this study, we report the characterization of 13 khadi isolates for the presence of brewing-relevant phenotypes such as their fermentative capacity, ability to utilize a range of carbon sources and their ability to withstand brewing-associated stresses, as a principal step towards selection of starter cultures. Khadi isolates such as Saccharomyces cerevisiae, Saccharomycodes ludwigii and Candida ethanolica showed good brewing credentials but Lachancea fermentati emerged as the isolate with the best brewing attributes with a potential as a starter culture. However, we were then prompted to investigate the potential of L. fermentati to influence the fruity aromatic flavor, characteristic of khadi. The aroma components of 18 khadi samples were extracted using headspace solid phase micro-extraction (HSSPME) and identified using a GC-MS. We detected esters as the majority of volatile compounds in khadi, typical of the aromatic signature of both khadi and L. fermentati associated fermentations. This work shows that L. fermentati has potential for commercial production of khadi.

Changes in Bacterial Composition During Maturing Stages of Salt Fermentation of Pangas (Pangasianodon hypophthalmus)

ABSTRACT Pangas fish (Pangasianodon hypophthalmus) was fermented naturally with salt at room temperature for 180 days and representative culturable bacteria from the entire maturation period at 15 days interval were isolated by plating in media containing 5% and 15% salt and identified using 16SrRNA gene sequence analysis. Total 80 no of bacterial isolates belonging to genera such as Bacillus, Staphylococcus, Oceanobacillus, Halomonas, Chromohalobacter, Virgibacillus etc. were identified from late maturation phase. Staphylococcus, Bacillus and Halomonas spp. were dominant from early maturation phase whereas Chromohalobacter spp. and Virgibacillus spp. appeared from 90th day onward and persisted till the final maturation. Bacillus licheniformis and Chromohalobacter canadensis were dominant bacterial species on 5% and 15% salt containing plates respectively from 90th day until final maturation. The dominant isolates showed good proteolytic and moderate lipolytic activities along with good growth during salt fermentation indicating that they are potential starter cultures for acceleration of the fermentation process.

Effects of Lactobacillus sakei inoculation on biogenic amines reduction and nitrite depletion of chili sauce

In this study, the effects of the starter culture Lactobacillus sakei on pH, the total lactic acid concentration, nitrite depletion and histamine reduction of chili sauce were investigated. The nitrite concentration in the CPN sample was significantly lower (p < 0.05) than that of the CPS sample (as control), and decreased by 30.87%.The putrescine and histamine concentration in starter culture inoculated chili sauce were significantly lower (p < 0.05) than that of the control sample, and were decreased by 38.08% and 49.88%, respectively. These results revealed that L. sakei could be used as a potential starter culture for nitrite depletion and biogenic amines reduction of chili sauce with good sensory attributes.

Unraveling the effects of Lactobacillus sakei inoculation on the microbial quality and bacterial community diversity of chili sauce by high-throughput sequencing

In this study, the effects of the starter culture Lactobacillus sakei on microbial quality and the bacterial community diversity of chili sauce were investigated. In starter culture inoculated chili sauce (CPN sample), Lactobacillus spp. was predominant bacteria with 86.08% of the relative abundance on the 30th day of fermentation. Meanwhile, the spoilage organisms and pathogenic bacteria, including Staphylococcus spp., Enterobacter spp., Pseudomonas spp. and Neorhizobium spp. were nearly undetectable in starter culture inoculated chili sauce. In contrast, Lactobacillus spp. and Weissella spp. were predominant bacteria, and trace Pseudomonas spp. and Neorhizobium spp. were still detectable at the end of fermentation in the spontaneous fermentation (CPS sample). These results revealed that L. sakei could be used as a potential starter culture for the microbial quality improvement.

Technological and Safety Characterization of Kocuria rhizophila Isolates From Traditional Ethnic Dry-Cured Ham of Nuodeng, Southwest China.

Nuodeng ham is known for its unique processing techniques and flavor. In the present study, proteolytic microorganisms from cured artisanal Nuodeng ham were investigated in order to identify and select potential starter cultures for its faster and safer fermentation. Eight isolates, accounting for 57% of proteolytic microorganisms, were found to be related to Kocuria rhizophila. Relevant properties of K. rhizophila as potential starter culture were evaluated in vitro for the first time. Intra-species diversities were found in phylogenetic and physiological properties of K. rhizophila isolates. Nevertheless, desirable attributes, such as halo-tolerance, nitrate reductase and protease activity, as well as the absence of antimicrobial resistance and amino acid decarboxylase activity, were observed in selected isolates. Moreover, genome analysis of isolates K24 and K45 confirmed their lack of typical genes for virulence, antimicrobial resistance and amino acid decarboxylase. K. rhizophila may thus represent a novel starter candidate of coagulase-negative cocci group and contribute to color and flavor development of fermented meats.

Application of lactic acid bacteria for improving the quality of reduced-salt dry fermented sausage: Texture, color, and flavor profiles

The traditional dry sausage is highly appreciated in China because of its unique quality characteristics, but it contains high salt content. Hence, this study aimed to evaluate the effects of lactic acid bacteria (LAB) comprising Lactobacillus sakei (LS), Lactobacillus curvatus (LC), Lactobacillus plantarum (LP), and Weissella hellenica (WH) on the quality attributes of the reduced-salt dry fermented sausages. The results indicated that the LP sausage showed higher (P < 0.05) shear force value compared to the other sausages, while the LP, LC, and WH sausages had higher (P < 0.05) lightness values than the control sausages. Seventy-six volatile compounds were detected, and nine compounds were identified as the key differential volatile compounds among the sausages based on partial least squares discriminant analysis. Clustering analysis of electronic nose results corresponded well to the volatile compound results. The sensory evaluation confirmed that the inoculation with LC and LP had a positive impact on the aroma, color, and hardness attributes of the reduced-salt sausages. Besides, partial least squares regression analysis further indicated that L. curvatus and L. plantarum could be used as the potential starter cultures to manufacture reduced-salt dry fermented sausage having improved texture, color, and flavor.

Evaluation of the Relationship among Biogenic Amines, Nitrite and Microbial Diversity in Fermented Mustard.

Biogenic amines (BAs) and nitrites are both considered harmful compounds for customer health, and are closely correlated with the microorganisms in fermented mustard (FM). In this study, BAs and nitrite contents in fifteen FM samples from different brands were analyzed. The concentrations of cadaverine in one sample and of histamine in one sample were above the toxic level. Moreover, five FM samples contained a high level of nitrite, exceeding the maximum residue limit (20 mg/kg) suggested by the National Food Safety Standard. Then, this study investigated bacterial and fungal communities by high-throughput sequencing analysis. Firmicutes and Basidiomycota were identified as the major bacteria and fungi phylum, respectively. The correlations among microorganisms, BAs and nitrite were analyzed. Typtamine showed a positive correlation with Lactobacillus and Pseudomonas. Cadaverine and nitrite is positively correlated with Leuconostoc. Furthermore, thirteen strains were selected from the samples to evaluate the accumulation and degradation properties of their BAs and nitrite. The results indicated that the Lactobacillus isolates, including L. plantarum GZ-2 and L. brevis SC-2, can significantly reduce BAs and nitrite in FM model experiments. This study not only assessed the contents of BAs and nitrite in FM samples, but also provided potential starter cultures for BAs and nitrite control in the FM products industry.

Controlled fermentation of curly kale juice with the use of autochthonous starter cultures

The aim of this paper was to evaluate the influence of different indigenous lactic acid bacteria isolates – as a single culture or bacterial consortium – on the functional and physicochemical properties of fermented curly kale juice. All tested variants exhibited good growth parameters, manifested by efficient pH lowering, increases in acidity, and fructose and glucose metabolism, as well as a significant inhibition of pathogens. A slight increase in total phenolic content was observed, while antioxidant activity remained unchanged. L. sakei and MIX A were associated with an increase in riboflavin and pyridoxine content, while L. plantarum only contributed to an increase in vitamin B6 content. Bioconversion of individual phenolic compounds, carotenoids, and glucosinolates strongly depended on the strain-specific metabolism. In the process, the levels of ferulic acid and other hydroxycinnamic acids were maintained, while the content of 9-cis lutein increased. Considering presented results and our previous research regarding probiotic features of LAB strains, among tested starter cultures – L. plantarum seemed to possess the best characteristics as a potential starter culture for controlled fermentation of curly kale juice.

Identification of Potential Probiotics Producing Bacteriocins Active against Listeria monocytogenes by a Combination of Screening Tools.

Listeria monocytogenes is an important food-borne pathogen and a serious concern to food industries. Bacteriocins are antimicrobial peptides produced naturally by a wide range of bacteria mostly belonging to the group of lactic acid bacteria (LAB), which also comprises many strains used as starter cultures or probiotic supplements. Consequently, multifunctional strains that produce bacteriocins are an attractive approach to combine a green-label approach for food preservation with an important probiotic trait. Here, a collection of bacterial isolates from raw cow’s milk was typed by 16S rRNA gene sequencing and MALDI-Biotyping and supernatants were screened for the production of antimicrobial compounds. Screening was performed with live Listeria monocytogenes biosensors using a growth-dependent assay and pHluorin, a pH-dependent protein reporting membrane damage. Purification by cation exchange chromatography and further investigation of the active compounds in supernatants of two isolates belonging to the species Pediococcus acidilactici and Lactococcus garvieae suggest that their antimicrobial activity is related to heat-stable proteins/peptides that presumably belong to the class IIa bacteriocins. In conclusion, we present a pipeline of methods for high-throughput screening of strain libraries for potential starter cultures and probiotics producing antimicrobial compounds and their identification and analysis.

Optimization of Protective Agents for Freeze-Drying of Weisella cibaria N9 as a Potential Starter Culture

Bu çalışmada ekşi hamurdan izole edilmiş ve starter kültür olarak kullanılabileceği belirlenmiş Weissella cibaria N9 suşunun liyofilizasyonu için optimum kriyoprotektan formülasyonunun belirlenmesi, liyofilize kültürün karakterizasyonu ve depolama stabilitelerinin belirlenmesi amaçlanmıştır. Liyofilizasyon sonrası yüksek canlılık sağlamak için kullanılacak yağsız süt tozu (YST), laktoz ve sükroz’dan oluşan optimum formülasyon Box Behnken tasarımı kullanılarak belirlenmiştir. Optimum kriyoprotektan formülasyonu yüksek canlılık (&gt;%99) için %5.65 YST, %20 laktoz ve %9.38 sükroz şeklinde tanımlanmıştır. Optimum kriyoprotektan formülasyonu kullanılarak elde edilen liyofilize kültürün nem içeriği, aw, camsı geçiş, partikül yüzey özellikleri ve kristal yapı bakımından kabul edilebilir fizikokimyasal özelliklere sahip olduğu gözlenmiştir. 3.37x10-3 1/gün inaktivasyon katsayısı ile en yüksek canlılık (9.11 log kob/g) 4C’de depolama sonunda elde edilmiştir. Sıcaklığa bağlı hızlandırılmış raf ömrü testi sonucu en hızlı canlılık kaybı 70C’de gözlenmiş olup kriyoprotektan kullanımı termal ölüm oranını azaltmıştır. Kriyoprotektan kullanılarak üretilen kültürün oda sıcaklığında 18 ay saklanabileceği belirlenmiştir. Sonuç olarak, optimum kriyoprotektan formülasyonu W. cibaria N9’un liyofilizasyonu ve depolama sırasında hücre canlılığını korumada etkili olduğu, toz materyaller için gerekli özellikleri taşıdığı ve uzun dönem muhafaza için canlılığın yeterli hassasiyette tahmin edilmesinde sıcaklığa bağlı hızlandırılmış raf ömrü testinin faydalı bir teknik olduğu tespit edilmiştir.

The effects of ropy exopolysaccharide-producing Lactiplantibacillus plantarum strains on tarhana quality

Tarhana, a traditional fermented food, is one of the earliest instant soups, consumed for centuries by the Anatolians and used as infant nutrition due to its high cereal, vegetable and dairy content. Improving tarhana's desired consistency and health-promoting properties while maintaining its functionality may expand the consumption of this traditional food. The aim of this study is to use recently characterised, EPS-producing Lactiplantibacillus plantarum strains to produce functional tarhana with improved technological properties. Ropy EPS-producing L. plantarum strains were able to grow and produce EPS during the fermentation of tarhana, which enabled the production of tarhana samples with acceptable quality. EPS-producing L. plantarum strains showed a greater than 2-fold higher consistency index than tarhana samples fermented without EPS L. plantarum strains. EPS produced by L. plantarum strains maintained the desired reddish colour of tarhana powders during 90 days of storage. Sensory analysis scores were highest for the two tarhana samples fermented with L. plantarum PFC309 + PFC310 and PFC310 + PFC311. In conclusion, it was determined that ropy EPSs produced by L. plantarum strains effectively maintained the desired red colour of tarhana and improved the viscosity of tarhana soups. Additionally, L. plantarum PFC309 and PFC311 strains are potential starter cultures able to produce and improve the functionality of tarhana with respect to technological and health aspects.