Starter Lactic Acid Research Articles

Bio-process optimization for developing a turmeric (Curcuma longa Linn.) beverage fermented with functional lactic acid starter cultures

Turmeric, scientifically known as Curcuma longa, is a herbaceous plant characterized by its rhizomatous nature with remarkable chemical composition and biologically active compounds. Lactic acid bacteria (LAB) have been observed to break down complex polyphenols into simpler, more bioactive compounds through fermentation. The success of the fermentation process relies on various factors to achieve the desired end product. This study's main goal was to assess the feasibility of using turmeric as a fermentable substrate for LAB, with the intention of creating a non-dairy fermented beverage. The investigation delved into the impact of several fermentation parameters, namely Fermentation Temperature, pH (Lemon juice concentration), Inoculum concentration, and Substrate concentration (Turmeric concentration), on the phytochemical and antioxidant properties of the lactic acid-fermented turmeric beverage (FTB). Statistical analysis revealed that a quadratic polynomial model could effectively illustrate how these fermentation parameters influenced the beverage's phytochemical and antioxidant qualities. Visualization through response surface plots revealed that these independent variables significantly influenced the beverage's total phenolic content, total flavonoid content, and antioxidant properties. Optimal fermentation conditions were identified to yield the highest levels of phenolic, flavonoid, and antioxidant content. These conditions included a Fermentation Temperature of 37.45 °C, a pH of 5.62, an Inoculum concentration of 5.12%v/v, and a Substrate (turmeric) concentration of 2.28%w/v. Under these precise conditions, experimental results closely aligned with predicted values for total phenolic content (57.46mg/100 ml), total flavonoid content (51.48mg/100 ml), and total antioxidant activity (72.24%). The overall acceptability of the fermented turmeric beverage reached a high 98.10%. Notably, the FTB exhibited significantly improved attributes such as astringency, flavor, taste, and overall acceptability when compared to the non-fermented turmeric beverage (NFTB), with statistical significance (P < 0.05).

Microbial diversity, aflatoxin M1 contamination and potential lactic acid starters for commercially produced traditional fermented dairy beverages, a case of Bongo from Uganda

This was a cross sectional study that examined the microbial ecology and aflatoxin M1 contamination in commercially produced Bongo, a traditionally fermented dairy beverage from Uganda. It also involved isolation and preliminary evaluation of defined starter cultures for Bongo. Microbial analyses were done by agar plating. Microbial identification was initially done by biochemical testing and microscopy. Followed by 16S rRNA and Internal Transcribed Spacer (ITS) region sequencing for bacteria and yeasts, respectively. Community DNA was studied using Next Generation Sequencing (NGS). Aflatoxin M1 was determined using Ultra High Pressure Liquid Chromatography - Triple Quadrupole Mass Spectrometry. (GTG)5 Rep PCR fingerprinting was used to cluster candidates for starter culture evaluation. The rates of acidification of cow milk by candidate LAB coupled with sensory acceptability of the milk they fermented were the criteria for the selection of the starter cultures. Results indicated that lactic acid bacteria (LAB) and yeasts were the dominant groups. Molds, coliforms, enterococci and staphylococci were also detected. Aflatoxin M1 were insignificant. Based on agar plating technique, lactococci and lactobacilli were dominant, however, NGS showed Streptococci. Agar plating also showed Saccharomyces as dominant, but NGS showed Dipodascus. Cluster analysis identified 18 LAB, which were evaluated for starter culture properties. Three showed promise suggesting that they could be used for commercial production of cultured milks like Bongo.

Modern methods of raw meat processing to reduce microbial contamination

There are various methods to preserve the quality and extend the expiration date of food products. Raw meat from different animal species is a highly perishable product. The relevance of this research is driven by the need to summarise contemporary knowledge on approaches and techniques aimed at extending the storage duration of safe and high-quality meat, alongside their scientific justification. This article focused on finding means to reduce bacterial contamination, as microorganisms are the primary cause of meat spoilage. This study aimed to identify the most promising and optimal methods for extending the freshness of raw meat. To conduct the analysis, information from scientific primary sources, and electronic resources was used, and the results of experimental data on the application of scientifically based safe approaches were studied. A review of the main methods and measures aimed at extending the storage period of raw meat was carried out. The advantages and disadvantages of various methods of raw meat processing that have a bactericidal or bacteriostatic effect on various, including pathogenic, microorganisms that not only cause meat spoilage but can also be a danger to the potential consumer were established. Various traditional, novel, and innovative methods are currently employed in meat processing. Given the advancements in science and technology, a comprehensive approach to raw meat processing is emerging as the most promising. After analysing the research findings of numerous scientists, it has been concluded that biological technologies utilising lactic acid bacteria, combined with traditional physical methods such as refrigeration, offer the most optimal solution. This approach preserves the freshness of meat while minimising the impact on organoleptic properties, provided that temperature regimes and processing technologies involving cultures of lactic acid microorganisms are adhered to. The practical significance of this study lies in identifying the most promising directions for further research and improving existing safe antimicrobial treatments, particularly through the use of various strains of lactic acid starters. Their practical application will enable the preservation of meat freshness and extend its storage life

The Effect of High-Pressure Processing of Caprine Milk on the Production and Properties of Yoghurt.

The aim of this study was to determine the suitability of HP-treated caprine milk for yoghurt production and to evaluate the effect of HP treatment on yoghurt properties. Reconstituted caprine milk was subjected to HP treatment (350 MPa/10 min/20 °C); a lactic acid starter culture (YC-X16, Chr. Hansen) was added. Milk was fermented at a temperature of 43 °C until pH 4.60. Bacterial counts, pH, color, rheological characteristics, texture, microstructure, and the sensory attributes of the yoghurt were determined after production and after seven days of storage at a temperature of 4 °C. HP treatment increased color saturation and whiteness index and induced a minor increase in milk pH. Minor differences in the acidification curve were noted. During storage, Streptococcus thermophilus counts were significantly higher in yoghurt from HP-treated than from untreated milk, whereas Lactobacillus delbruecki ssp. bulgaricus counts remained stable. A color analysis did not reveal differences between the experimental and control yoghurts. After storage, yoghurt made from HP-treated milk was characterized by thicker consistency and lower rheological stability than the control yoghurt. The micrographs of the yoghurts confirmed the differences in rheological parameters. Yoghurt produced from HP-treated caprine milk and stored for seven days received the highest scores in the sensory evaluation.

Production of High Protein MOCAF (Modified Cassava Flour) Using Papain and Lactic Acid Bacteria

Wheat is one of Indonesia's primary sources of carbohydrates. However, the need for wheat still depends on imports. So, developing local flour based on Indonesia's natural resources is necessary. One source of carbohydrates easily found in Indonesia is cassava (Manihot esculenta crantz). Although there are many in Indonesia, the diversification of cassava-based products is still limited. In this research, MOCAF flour was developed and produced by fermenting cassava tubers with lactic acid bacteria. The enzymatic activity during the MOCAF (Modified Cassava Flour) production process is believed to change the physicochemical properties of cassava so that MOCAF products have characteristics similar to wheat flour and are expected to meet the gap between the demand and availability of flour. Even though it can potentially substitute wheat, MOCAF flour only has about 1% protein content, influencing dough rheology. According to the problem, a process modification was done by adding the enzyme papain (PAP) as a support enzyme to improve the performance of lactic acid bacteria (LAB). In order to study the effect of the papain enzyme, variations were made on the ratio of lactic acid starter: papain enzyme (LAB: PAP) and fermentation time. The ratio of (LAB: PAP) was varied to 40:1, 40:3, 40:5, 40:7, and 40:9, while the fermentation period was varied to 24, 48, 72, 96, and 120 hours. The fermentation was conducted by using cassava varieties of Singkur aerobically. The primary starter contained Lactobacillus, sp, developed by PT. Rumah Mocaf Indonesia and the papain enzyme used have an activity of 100,000 U/g. Data analysis showed that the addition of papain enzyme doses with a ratio to the lactic acid starter of 40:7 was able to produce MOCAF with the best characteristics: protein content, starch content, and swelling power of 3.72%, 9.99%, 16.00%, respectively. The data trend of research also showed that the number of papain enzymes only significantly affects starch content and swelling power. On the other hand, fermentation time has a significant effect on these three characteristics (protein, starch, swelling power).&#x0D; &#x0D; Keywords: Cassava, fermentation, lactic acid bacteria, MOCAF (Modified Cassava Flour), papain enzyme

Study of the influence of dairy raw materials by seasons of the year on technological parameters in the production of soft cheese

Relevance. Milk and milk products are key food products in Russia. The main raw material for the production of cheese as an important component of the diet of citizens is milk, the main source of which is cattle. The Holshire breed is common in the Urals. Studying its features and improving the quality of milk (and therefore dairy products) is an urgent task for the agro-industrial complex of Russia.Methods. The purpose of the work is to study the influence of dairy raw materials by seasons on technological parameters in the production of soft cheese.Results. As a result of the research, it was found that the best quality was a clot from cows' milk for the 3rd and 4th lactation. To obtain it, less calcium chloride and whey were spent than in the manufacture of cheeses from cows' milk according to the 1st and 2nd lactation. It should also be noted that the duration of operations for the formation of a clot and work with it, as well as for self-pressing, was shorter in cows' milk for the 3rd and 4th lactation. In the manufacture of «Adygeisky» cheese on the other side of the enterprise, due to the introduction of rennet, the clot improved and the duration of self-pressing decreased, which had a positive effect on the quality of the product. The peculiarities in the manufacture of fresh «Amateur» and «Table» cheeses have been established, namely, certain differences in some technological operations, their duration and quality indicators of the clot and the separated whey. Thus, milk differed in the consumption of calcium chloride, lactic acid starter culture and rennet. The lowest consumption of these components turned out to be in the manufacture of cheese from milk of age-and-age cows. The milk of cows of the Holstein breed of the Ural selection is suitable for processing into soft cheeses regardless of the season of the year. However, the best indicators of technological properties are found in the milk of age-and-age cows for the 3rd and 4th lactation.

DEVELOPMENT OF A TECHNOLOGY FOR OBTAINING A PROBIOTIC STRAIN LACTOBACILLUS BULGARICUS C-2, PROMISING FOR THE PRODUCTION OF STARTER CULTURES AND BIOLOGICALLY ACTIVE ADDITIVES

Lactic acid probiotic bacteria can be widely used for the prevention and treatment of patients with various diseases, such as acute and chronic diseases of the gastrointestinal tract, respiratory tract, to restore intestinal microbiocenosis, in combination with antibiotic therapy. The form of intake of these microorganisms is diverse: fermented milk products, drugs, dietary supplements. In the production of lactic acid starters, including the probiotic strain Lactobacillus bulgaricus, there are problems in the selection of nutrient media and conditions for deep cultivation, the selection of methods and conditions for concentration, and the selection of cryoprotectants for freeze drying. This article presents all the data for the production of the Lactobacillus bulgaricus C-2 strain in powder form with the maximum yield of microorganism cells, promising for introduction into the composition of starter cultures for the dairy industry and into biologically active additives with a probiotic effect. The Lactobacillus bulgaricus C-2 strain was isolated from koumiss and stored in the collection of the branch of the Republican State Enterprise on the REM of the Ministry of Health of the Republic of Kazakhstan "National Center for Biotechnology" in Stepnogorsk. The production nutrient medium, conditions for deep cultivation, methods and conditions of concentration were selected, optimal cryoprotectants for freeze-drying were selected.

Antibacterial Activity Test of Yoghurt Paste Red Fruit (Pandanus conoideus Lam.) Against Escherichia coli

Background: Red fruit (Pandanus conoideus Lam.) contains phenol, terpenoid, alkaloid, tannin, and steroid compounds which function as antibacterial. Yoghurt is a fermented milk product with a manufacturing process by adding two types of lactic acid starter: Lactobacillus bulgaricus and Streptococcus thermophilous. Objective: This study aimed to determine the pH, water content, total solid content, ash content, total lactic acid, and antibacterial activity against Escherichia coli in red fruit (Pandanus conoideus Lam.) paste yoghurt. Method: This study used an experimental approach by making red fruit paste yoghurt in three formulas with different concentrations, namely F1 (10%), F2 (15%), and F3 (20%). An antibacterial activity test was conducted using the disc diffusion method. Results: The results obtained from all tests were the pH in formula 1, 2, and 3, namely 4.7; 4.9, and 4.9; the water content in formula 1, 2, and 3 were 63.33%; 44.66%, and 60.66%; the total solids content of formula 1, 2, and 3 were 36.66%; 55.33%, and 39.33%; the ash content in formula 1, 2, and 3 were 1.40%; 1.66%, and 1.13%; total lactic acid in formula 1, 2, and 3, namely 1.97%; 1.71%, and 2.09%; inhibition zone of antibacterial activity in formula 1, 2, and 3, namely 10.50 mm; 12.47mm, and 13.18mm. Conclusion: In total solids and total lactic acid qualified for Indonesian National Standard (SNI) requirements, while pH, water content, and ash content did not qualify for SNI requirements. Antibacterial activity in red fruit paste yoghurt is a potent category.

Improvement of the Nutritional Quality of Black Bean (&amp;lt;i&amp;gt;Phaseolus Vulgaris&amp;lt;/i&amp;gt; I.) Powder During Fermentation: Use of Lactic Starters

The objective of this study was to investigate lactic acid starters able to improve the nutritional quality of black bean powder (BBP) during fermentation. For this purpose, raw and cooked BBP was fermented with <i>Lactobacillus acidophilus</i> and BLHN7 isolate. After 120 hours of fermentation, the pH of medium was measured by pH meter, tannins and phytates by spectrophotometry, total proteins by the Kdjedhal method. The minerals by atomic absorption spectrophotometry and the total sugars by the phenol method. From these analyses, it was found that the pH decrease was not significantly different in BBP fermented with <i>Lactobacillus acidophilus</i> and BLHN7 isolate. This decrease in pH varied between 4.0 and 4.3. Principal Component Analysis (PCA) of the results shows the variability of nutritional parameters depending on the microorganisms used and the type of treatment applied to the BBP. However, a better increase in protein, iron and microbial growth is observed in the raw BBP fermented with <i>Lactobacillus acidophilus</i>. We observed an increase of 267, 240 and 118% respectively. It is also in the raw BBP that we observe a reduction of tannins and a small reduction of sugar content by 76 and 20% respectively. On the other hand, it is in the cooked BBP fermented with <i>Lactobacillus acidophilus</i> that phytates were reduced by 3.4% and magnesium increased by 180%. Calcium increased by 165% in cooked BBP fermented with BLHN7 isolate. Considering the effect of <i>Lactobacillus acidophilus</i> on the majority of the nutritional parameters studied, it would be interesting to use it to improve the nutritional quality of BBP as a dietary supplement for malnourished children.

Lactobacillus delbrueckii subsp. bulgaricus strain TCI904 reduces body weight gain, modulates immune response, improves metabolism and anxiety in high fat diet-induced obese mice

The multiple probiotic characteristics of strain TCI904 isolated in this study from natural fermented milk were investigated using a mouse model. TCI904 was identified as Lactobacillus delbrueckii subsp. bulgaricu (LDB), a well-known lactic acid starter bacterium found in yogurt. TCI904 exhibited an outstanding pancreatic lipase inhibition activity among several strains of lactic acid bacteria in vitro. Its in vivo effects were further studied. In a comparison of mice fed a high-fat diet (HFD) and those fed a HFD combined with TCI904 for 9 weeks, differences were observed in various aspects of health, and the adverse effects of a HFD were prevented in the latter group. TCI904 effectively prevented fat and body weight accumulation without reducing food intake; it also modulated innate immunity and increased the level of IgA in feces, reversing the increased blood sugar and insulin levels and attenuated the hyperlipidemia caused by a HFD. Based on biochemical test data, compared with the HFD group, a HFD combined with TCI904 induced significant lowering of insulin resistance indicator, homeostasis model assessment-insulin resistance (HOMA-IR) and atherogenic indices of plasma (AIP), the atherogenic coefficient (AC) and cardiac risk ratio (CRR) and increased the cardioprotective index (CPI). In addition, the administration of TCI904 alleviated mood disorders caused by a HFD. Taking the recommended human dose of TCI904 did not affect the liver or kidney function, indicating that TCI904 has sufficient in vivo safety. Taken together, the results of the present study contributed towards validation of the probiotic benefits of lactic acid starter microflora. Orally taken TCI904 exhibited positive immune- and metabolic-modulating, and anxiolytic properties, especially in HFD-induced obesity.

Identification of the influence of technological factors on the growth and development of lactic acid microorganisms in pastille marmalade products enriched with lactic acid starters

Prototypes of pastille marmalade products with starters of lactic acid microorganisms have been developed. Pastille marmalade products that contain live cells of probiotic culture (from 1 to 3 CFU/g) help strengthen and maintain immunity. The macro and micromorphology of the probiotic culture were investigated, which confirmed the belonging of microorganisms to lactic acid. The studies reported here were scientifically substantiated by the method of mathematical modeling. Based on the regression equation, it was revealed that the growth of lactic acid microorganisms in the product is affected by the volume of whey (250 ml), the volume (0.02 g) and the time of revival of the starter culture (6 hours). A more significant factor was the volume of application of lactic acid microorganisms, from 0.01 to 0.02 g, which affects the growth of lactic acid microorganisms (increases) in the product. The antimicrobial activity of isolated crops in relation to E. coli was studied. The zones of illumination of the isolated colonies in relation to E. coli range from 0.1 mm to 0.5 mm. The results show that antagonistic properties affect pathogenic and conditionally pathogenic microorganisms in the gastrointestinal tract. The antioxidant properties of pastille marmalade products have been established. When applying starters of lactic acid cultures, the volume of antioxidants increased by 1.7 and 2.2 times compared with control. In this regard, the development of pastille marmalade products with starters of lactic acid microorganisms is a relevant and promising task because they are natural, have an immunostimulating effect, and expand the range of confectionery products

Lactic acid bacteria as an adjunct starter culture in the development of metabiotic functional black pearl grapes beverage

Black pearl Grapes are highly nutritious and one of the richest sources of polyphenols, but due to being delicate with very high loss at harvest and during distribution, is not consumed adequately. This study intended to develop functional lactic acid starter culture based fermented grapes beverage, in order to improve the quality and stability of this low pH fruit and to develop a fermented non-dairy beverage. Results showed that grapes blend was an excellent matrix for LAB growth with more than 9.38 log10 CFUml-1 of viability at the end of fermentation. LAB fermentation affectedly enhanced the total polyphenols and flavonoids content. Likewise, antioxidants capacities based on DPPH and FRAP activity were considerably increased correlating with each other, impacting the color and sensory properties of the grapes beverage. This way, the lactic acid fermentation can be considered as an appropriate tool for developing black pearl grapes based novel bio-intervention with enhanced antioxidants, polyphenols and flavonoids with anti-proliferative activity and antagonistic efficacy against recurring food borne pathogen in this post-antibiotic era.

Using optimization method for determining lactic acid bacteria counts in white cheese with different salt concentrations

Total lactic acid bacteria, Lactococcus spp., yeast, and mold counts in white cheese were determined during 55 days of storage in brine solutions with 4%, 6%, 8%, 10%, 12%, 14%, and 16% (w/v) salt concentrations at 4°C. In addition to salt content, dry matter, acidity, protein, fat contents, and sensory evaluations of cheese were also determined. Lactococcus spp. numbers in cheese salted with 4% and 14% brines (w/v salt concentrations) were 9.32 and 8.48 log cfu/g at the 55 days of storage, respectively. The lowest total lactic acid number was 7.24 for cheese in brine with 16% (w/v) salt concentration after 55 days of storage. Yeast numbers were 7.01 and 6.71 log cfu/g for cheese in brines with 4% and 16% (w/v) salt concentrations. Cheese samples salted in 12% and 14% (w/v) concentrations of brines have the highest sensory scores. Analysis results were interpreted mathematically by “fuzzy soft set” modeling. Novelty impact statement This research is a novel study detailing mathematical modeling related to optimizing the salt concentration to preserve the viability of lactic acid starter culture bacteria in the white cheese. Also, it covers the first optimizing method for process control in the cheese industry with the application of “fuzzy soft set theory.”

What are the potential sources of on-farm contamination of raw milk butter with Escherichia coli?

Description of the subject. According to Regulation (EC) No 2073/2005, Escherichia coli must be enumerated in raw milk butter before sales. Hygiene of batches is acceptable when a maximum of two samples out of five have levels of E. coli between 10 and 100 cfu·g-1. E. coli is still a threat to the safety of raw milk butter. Objectives. This study aimed to identify sources of E. coli in six farms facing recurrent contaminations in butter. Method. Farms were visited three times between March and May 2021. Surface samples and dairy products samples were collected throughout the process for E. coli enumeration and assessment of potential correlations between equipment contamination and hygienic quality of food products. Results. Two major sources of contamination were identified: the lack of efficacy of cleaning and disinfection practices on milk pipelines, junctions and cream separators, and absence of milk cooling in case of time-lapse of more than 2 h between milking and skimming. The use of lactic acid starters could be a helpful way to control E. coli during cream maturation, in association to adequate good manufacturing practices. Conclusions. Levels of E. coli in the considered raw milk butter batches were really high. A new decision tree is proposed that could help manufacturers and food controllers to improve hygienic quality of raw milk butter.

Correction of poultry microbiocenosis by a complex of sour milk and propionic microorganisms

In the necessary correction and prevention of dysbacteriosis in animals and humans, the main role is played by the use of probiotics. Probiotics are live microbial supplements that have a beneficial effect on the body by forming a full-fledged barrier of the intestinal mucosa, preventing the attachment of pathogens to it, modulating the body’s defense mechanisms and improving the balance of intestinal microflora. This is achieved by directly antagonizing bacteria and increasing the effectiveness of the immune response. The normal microflora of the intestine of poultry is 99% composed of anaerobic bacteria. It was found that probiotics activate the tissue and humoral immunity of animals (T- and Blymphocyte systems), affect the production of immunoglobulins. To study the effect of a probiotic complex based on fermented milk and propionic microorganisms Streptococcus lactis and Lactobacillus acidophilus, an experiment was carried out on broiler chickens of the KOBB-500 cross. The feed additive “Prolaxim-V” was introduced with water in the watering system in the amount of 0.2 ml per 1 bird/ day. Its use increased the gain in live weight of chickens by 10.4%, improved the indices of intestinal microbiocenosis. The number of lactobacilli, lactococci and bifidobacteria in the intestine increased 5 times compared to the control. Based on the data obtained, it can be concluded that the use of lactic acid starter cultures with live lactobacilli in poultry diets during growing periods should be recommended to obtain higher growth rates, improve the physiological state of animals and the quality of meat products

Technological techniques that improve the siloing conditions of perennial leguminous herbs

Perennial leguminous herbs due to their technological and ecological role in modern agriculture, taking into account the economic benefits of their use for fodder purposes, are priority raw materials for the procurement of high-quality bulky feed at the present stage of development of agricultural production in Russia. However, in the early stages of its development and at the maximum concentration of energy and nutrients in the dry substance, such raw materials slowly dry and are poorly siloed due to high moisture content. Weak drying optimizes the moisture silage of raw materials, but cannot guarantee a reliable result of preservation due to the low sugar content. Preservation of such raw materials with chemical and biological preparations can improve the result. The purpose of our development was to test biological preparations with cellulose-lytic properties, such as bacillusspecies, Aliciclobacillus acidocaldaris and Aeromonas species, to improve the quality of fermentation of perennial legumes–meadow clover. In a short-term (three-day) reconnaissance experiment, these preparations stimulated an increase in total acid formation, including lactic acid synthesis, and provided acidification of the mass to optimal limits (pH = 4.0-4.2). In a medium-term experience (three months) in the silage of freshly dried raw materials, such abilities were shown by the lactic acid starter Biosil NH, the best of the cellulose-lytic preparations when preserving the dried mass was B.species. In experiments good results were also obtained from the use of A.species. Researchers have shown the value of using of weak drying and biological products to obtain stable silage from clover meadow.

Evaluation of the Effect of Auxiliary Starter Yeasts With Enzyme Activities on Kazak Cheese Quality and Flavor.

To investigate the effect of yeasts on Kazak cheese quality and flavor, three isolated yeasts (Kluyveromyces marxianus A2, Pichia kudriavzevii A11, and Pichia fermentans A19) were used to ferment cheeses and designated as StC, LhC, and WcC, respectively. The cheese fermented with a commercial lactic acid starter without adding yeast was used as control named LrC. The results showed that the texture of cheese added with yeasts were more brittle. K. marxianus A2 contributed to the formation of free amino acids and organic acids, especially glutamate and lactic acid. Moreover, K. marxianus A2 provides cheese with onion, oily, and floral aromas. Furthermore, P. kudriavzevii A11 promotes a strong brandy, herbaceous, and onion flavor. Although no significant aroma change was observed in PfC, it promoted the production of acetic acid, isoamyl acetate, and phenethyl acetate. These results indicate that yeasts are important auxiliary starters for cheese production.

Изучение влияния различных ингредиентов на органолептические и функционально-технологические свойства сердца говяжьего

Offals are of interest to both factures of meat products and consumers. At the same time, the ambiguity of the organoleptic properties of offals and the lasted of their processing create barriers to the growth of their consumption. The studies carried out allowed us to demonstrate the most effective approaches to obtain the necessary organoleptic properties of a product with high functional -technological characteristics. The most effective approach to improve the properties of products from beef heart is using of lactic acid starter culture and citric acid.

Impact of cultivation strategy, freeze-drying process, and storage conditions on survival, membrane integrity, and inactivation kinetics of Bifidobacterium longum

Bifidobacterium longum, one of the main microorganisms in the human gut, is used as an adjunct to lactic acid starter cultures or sold as a probiotic product. Therefore, Bifidobacterium longum cell suspensions get freeze-dried with protective additives to prevent activity losses. To date, investigations covering growth and inactivation kinetics of Bifidobacterium longum during the whole process (cultivation, drying, and storage) have been lacking. In this study, the effect of cultivation conditions and shelf temperature as well as the influence of protectants (maltodextrin, glucitol, trehalose) at various concentrations on cell survival during freeze-drying was assessed. Drying was followed by a storage at + 4 °C and + 20 °C for 70 days to evaluate inactivation kinetics. The impact of the different factors was assessed by measuring surival rate and residual moisture content at various points of time over the whole process. In parallel cell membrane integrity and glass transition were determined to reveal inactivation effects. Cultivation strategy had a strong influence on survival with a huge potential for process improvement. A pH of 6.0 at the growth optimum of the strain provides better conditions regarding cell survival after drying than free acidification (non-regulated pH conditions). During the drying step, membrane leakage due to the removal of water is the main reason for the inactivation in this process step. In this study, the highest survival of 49% was obtained with cells dried at + 35 °C shelf temperature with an addition of maltodextrin (75% bacterial dry matter, w/w). The results show that Bifidobacterium longum cells are mostly inactivated during drying, whereas storage conditions at + 4 °C with an addition of 75% BDM maltodextrin relative to bacterial dry mass prevent cell loss completely.

Probiotic Potential of Lactic Acid Starter Cultures Isolated from a Traditional Fermented Sorghum-Millet Beverage.

The purpose of this study was to establish the probiotic potential of lactic acid bacteria (LAB) starter cultures, Lb. plantarum MNC 21, L. lactis MNC 24, and W. confusa MNC 20, isolated from a traditionally fermented sorghum-millet beverage from Uganda. The cultures were examined for tolerance to acid and bile salts, bile salt hydrolase (BSH) activity, antibiotic susceptibility, biogenic amine production, mucin degradation, hydrophobicity, auto-aggregation, adherence to the ileum, coaggregation, and antimicrobial properties against selected pathogenic species. Lb. rhamnosus yoba 2012, a known probiotic, was the reference. The isolates were tolerant to acid (pH = 3) and bile (1%). W. confusa MNC 20 and Lb. plantarum MNC 21 exhibited medium BSH activity (11–15 mm diameter of hydrolysis zone) while L. lactis and Lb. rhamnosus yoba 2012 exhibited low BSH activity (<10 mm diameter of hydrolysis zone). All isolates lacked mucolytic activity. Lb. plantarum MNC 21 and W. confusa MNC 20 produced agmatine. The candidate and reference microorganisms were resistant to 10 of 21 and 5 of 21 antibiotics, respectively. The isolates exhibited hydrophobic, auto-aggregation and coaggregation properties. These three properties were exhibited more (p < 0.05) by the reference than the potential probiotics. The ability of the potential probiotics to attach onto the goat ileum (7.3–8.0 log cfu/cm2) was comparable to that of Lb. rhamnosus yoba 2012 (7.6 log cfu/cm2). The four LAB inhibited E. coli, S. aureus, and S. enterica to the same extent (p < 0.05). The findings indicated potential probiotic activity of the starter cultures. However, further in vivo examination of these isolates is required to confirm their probiotic capabilities.