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1.
Food Chem ; 448: 139117, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38608398

RESUMO

This study aimed to determine the impact of supplementation with probiotically fermented chickpea (Cicer arietinum L) seeds on the quality parameters and functional characteristics of wheat bread. The addition of chickpea seeds caused significant changes in the chemical composition of the control wheat bread. The legume-supplemented products exhibited higher values of a* and b* color parameters and higher hardness after 24 h of storage than the control. The application of fermented or unfermented chickpeas contributed to an increase in total polyphenol and flavonoid contents, iron chelating capacity, and antioxidant properties of the final product. The variant containing unfermented seeds had the highest riboflavin content (29.53 ± 1.11 µg/100 g d.w.), Trolox equivalent antioxidant capacity (227.02 ± 7.29 µmol·L-1 TX/100 g d.w.), and free radical scavenging activity (71.37 ± 1.30 % DPPH inhibition). The results of this preliminary research have practical importance in the production of innovative bakery products with potential properties of functional food.


Assuntos
Antioxidantes , Pão , Cicer , Fermentação , Probióticos , Cicer/química , Pão/análise , Antioxidantes/química , Antioxidantes/análise , Probióticos/análise , Probióticos/química , Sementes/química , Flavonoides/análise , Flavonoides/química , Polifenóis/química , Polifenóis/análise , Alimento Funcional/análise , Triticum/química , Triticum/metabolismo
2.
Foods ; 12(21)2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37959152

RESUMO

Increasingly, consumers are looking for products with specific nutritional and health-promoting properties. The answer of the producers for this demand is fortified food. The raw material that can be used to enrich food is, among others, mushrooms. Crude water soluble polysaccharides (cWSP) were isolated from fruiting bodies of Pleurotus ostreatus (oyster) mushroom. Chemical analysis showed that they consisted mainly of carbohydrates (~61%), protein (~9%) and phenolics (~0.8%). The isolated cWSP were used to obtain enriched cow milk set yogurts. cWSP were added at the concentration of 0.1%, 0.2%, 0.3%, 0.4% and 0.5%, and milk containing no cWSP was prepared as the control. All of the variants were fermented via applying two commercially available culture starters. The addition of cWSP led to a drop in pH in the case of one starter culture. Also, the decline in total soluble solids (TSS) content was higher where cWSP was used for the enrichment. Texture profile analysis (TPA) revealed that parameters of hardness and gumminess increased along with the concentration of cWSP (reaching values approximately 7-8 times higher, compared to the control). A significant increase in syneresis level (proportional to cWSP concentration and ranging from ~10% to ~50%) was also observed after the fermentation. Fortifying milk with cWSP led to a slight increase in antioxidant capacity in FRAP assay (up to ~12%) and ABTS assay (up to ~23%). The results demonstrate that using cWSP to enrich set-type yogurts is fairly limited.

3.
J Food Sci ; 88(10): 4169-4179, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37712742

RESUMO

This study analyzed the effect of the inclusion of legume-derived proteins, specifically pea and fava bean protein, with varying solubility levels on the expansion of corn starch. Three different proteins exhibiting low, medium, or high solubility were mixed with corn starch to obtain blends containing 15%, 25%, and 35% (w/w) of the protein. Extrusion was performed on a twin-screw extruder at three different screw speeds (200, 400, and 600 rpm), a moisture content of 16% (w.b.), and a die temperature of 140°C. Obtained extrudates were analyzed for their expansion, unit density, and hydration properties, namely, water solubility index (WSI) and water absorption index (WAI). Extrudates containing the protein with the highest solubility showed different patterns than those that had proteins with low or medium solubility. Expansion ratio (ER) increased from a maximum of 3.55 ± 0.24 for pure corn starch up to 5.45 ± 0.43 when incorporating 35% of the protein with medium solubility but significantly decreased down to 1.24 ± 0.08 when incorporating 35% of the most soluble protein. The influence on the system parameters, as well as on the hydration properties, was also greatest for the blends containing the protein with the highest solubility. Even though significant Pearson correlations were observed between protein solubility and ER (r = -0.579), unity density (r = 0.614), WSI (r = -0.634), torque (r = -0.612), as well as specific mechanical energy (r = -0.451), further research is needed to evaluate if the solubility is indeed the reason for certain behaviors or if other protein characteristics are more critical for expansion. PRACTICAL APPLICATION: This manuscript provides practical information on the influence of the addition of legume-derived proteins with different solubility levels on direct expansion. The obtained results may help the industry with the selection of the appropriate proteins for inclusion levels in producing high protein direct-expanded extruded food products.

4.
Molecules ; 28(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37630242

RESUMO

Membranes produced by crosslinking chitosan with magnesium phytate were prepared using highly deacetylated chitosan and its N-carboxymethyl, O-carboxymethyl and N,O-carboxymethyl derivatives. The conditions of the membrane production were described. IR, Raman, electron absorption and emission spectra were measured and analyzed for all the substrates. It was found that O-carboxymethyl chitosan derivative is the most effectively crosslinked by magnesium phytate, and the films formed on this substrate exhibit good mechanical parameters of strength, resistance and stability. Strong O-H···O hydrogen bonds proved to be responsible for an effective crosslinking process. Newly discovered membrane types produced from chitosan and magnesium phytate were characterized as morphologically homogenous and uniform by scanning electron microscopy (SEM) and IR measurements. Due to their good covering properties, they do not have pores or channels and are proposed as packaging materials.

5.
Foods ; 11(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35681303

RESUMO

The aim of the study was to assess changes in the basic quality parameters induced by controlled lactic fermentation of fruiting bodies of the button mushroom (Agaricus bisporus). Lactiplantibacillus plantarum 299v with documented probiotic properties and L. plantarum EK3, i.e., an isolate obtained from spontaneously fermented button mushrooms, were used as starter strains. The fruiting bodies of fresh, blanched, and fermented mushrooms were analyzed at different stages of the lactic fermentation process. The content of free sugars (high-performance liquid chromatography with charged aerosol detector method; HPLC-CAD) and organic acids (high-performance liquid chromatography with diode array detector method; HPLC-DAD) was determined both in the mushroom fruiting bodies and in the brine. Five free sugars (ribose, trehalose, sucrose, glucose, and fructose), mannitol, and six organic acids (lactic, malic, succinic, citric, acetic, and fumaric acids) were detected in the samples. Lactic acid dominated in the final products. The starter cultures exhibited varying degrees of utilization of available mushroom sugars and sucrose used as an additional substrate. Sucrose was utilized at a higher rate and in greater amounts by the L. plantarum EK3 isolate. This starter culture was characterized by a significantly higher final amount of produced lactic acid, a lower pH value, and higher numbers of LAB (lactic acid bacteria). These important quality parameters largely determine the stability of fermented products. Based on the analysis results and the high scores in the organoleptic evaluation of the fermented mushrooms, the L. plantarum EK3 isolate can be recommended as an appropriate starter culture for lactic fermentation of mushroom fruiting bodies.

6.
Foods ; 10(11)2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34829159

RESUMO

This study is a brief report on the proteolytic activity of curly kale leaf extract against casein. Casein degradation products and an in silico analysis of the biological activity of the peptides obtained was performed. The efficiency of casein hydrolysis by curly kale extract was determined using SDS-PAGE and by peptide concentration determination. The pattern of the enzymatic activity was determined by MALDI-TOF MS analysis. The results showed that α- and ß-casein were more resistant to curly kale extract hydrolysis, whereas κ-casein was absent in the protein profile after 8 h of proteolysis, and all casein fractions were completely hydrolyzed after 24 h of incubation. Based on sequence analysis, seven peptides were identified, with molecular mass in the range of 1151-3024 Da. All the peptides were products of ß-casein hydrolysis. The identified amino acid sequences were analyzed in BIOPEP, MBPDB, and FeptideDB databases in order to detect the potential activities of the peptides. In silico analysis suggests that the ß-casein-derived peptides possess sequences of peptides with ACE inhibitory, antioxidant, dipeptidyl peptidase IV inhibitory, antithrombotic, immunomodulatory, and antiamnesic bioactivity. Our study was first to evaluate the possibility of applying curly kale leaf extract to generate biopeptides through ß-casein hydrolysis.

7.
Int J Food Sci ; 2021: 8822161, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33954168

RESUMO

The objective of this investigation was to verify whether biologically active peptides (BAPs) could be obtained from water solutions of α-lactalbumin (α-la) and caseinoglycomacropeptide (CGMP) through an application of the new Lactobacillus helveticus strains. Also, the aim of this research was to determine the influence of addition of the analyzed protein preparations to milk subjected to fermentation by tested bacterial strains on the physicochemical properties of obtained milk beverages. The results indicate that CGMP is a more preferable source for the production of BAPs by the test bacteria than α-la. The antihypertensive and ACE inhibitory effects were the most widespread bioactivities among the detected BAPs. α-la containing fermented milk beverages had higher values of springiness, gumminess, chewiness, and resilience than analogous products containing CGMP, while CGMP-supplemented fermented products exhibited higher values of the hardness parameter. The highest values of hardness (0.416 ± 0.05 N) were recorded for beverages fermented by DSMZ containing the addition of CGMP, while the lowest value of this parameter (0.186 ± 0.06 N) was noted for products containing α-la and fermented by B734. Moreover, CGMP-containing fermented products were characterized by a generally higher value of the proteolysis index (PI) than analogous variants containing α-la. The use of analyzed strains and the selected protein preparations has a positive effect on the texture of fermented milk beverages and might contribute to an increase in the health-promoting potential of such products.

8.
Int J Mol Sci ; 22(7)2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33917427

RESUMO

The production of mead holds great value for the Polish liquor industry, which is why the bacterium that spoils mead has become an object of concern and scientific interest. This article describes, for the first time, Lactobacillus hilgardii FLUB newly isolated from mead, as a mead spoilage bacteria. Whole genome sequencing of L. hilgardii FLUB revealed a 3 Mbp chromosome and five plasmids, which is the largest reported genome of this species. An extensive phylogenetic analysis and digital DNA-DNA hybridization confirmed the membership of the strain in the L. hilgardii species. The genome of L. hilgardii FLUB encodes 3043 genes, 2871 of which are protein coding sequences, 79 code for RNA, and 93 are pseudogenes. L. hilgardii FLUB possesses three clustered regularly interspaced short palindromic repeats (CRISPR), eight genomic islands (44,155 bp to 6345 bp), and three (two intact and one incomplete) prophage regions. For the first time, the characteristics of the genome of this species were described and a pangenomic analysis was performed. The concept of the pangenome was used not only to establish the genetic repertoire of this species, but primarily to highlight the unique characteristics of L. hilgardii FLUB. The core of the genome of L. hilgardii is centered around genes related to the storage and processing of genetic information, as well as to carbohydrate and amino acid metabolism. Strains with such a genetic constitution can effectively adapt to environmental changes. L. hilgardii FLUB is distinguished by an extensive cluster of metabolic genes, arsenic detoxification genes, and unique surface layer proteins. Variants of MRS broth with ethanol (10-20%), glucose (2-25%), and fructose (2-24%) were prepared to test the strain's growth preferences using Bioscreen C and the PYTHON script. L. hilgardii FLUB was found to be more resistant than a reference strain to high concentrations of alcohol (18%) and sugars (25%). It exhibited greater preference for fructose than glucose, which suggests it has a fructophilic nature. Comparative genomic analysis supported by experimental research imitating the conditions of alcoholic beverages confirmed the niche specialization of L. hilgardii FLUB to the mead environment.


Assuntos
Genoma Bacteriano , Mel/microbiologia , Lactobacillus/genética , Filogenia , Lactobacillus/isolamento & purificação , Sequenciamento Completo do Genoma
9.
Foods ; 9(11)2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33171613

RESUMO

The aim of the investigation was the identification and initial study of lactic acid bacteria (LAB) isolated from spontaneously fermented (at 28 °C for 5 days) fruiting bodies of white button mushrooms (Agaricus bisporus). The isolated LAB were preliminarily characterized applying the MALDI-TOF Biotyper. Moreover, further phenotypical, genotypical characteristics as well as some functional and technological properties of the selected microorganisms (including the ability to produce exopolysaccharides, cell hydrophobicity, resistance to low pH, and bile salt) were also analyzed. Among autochthonous LAB (isolated from the tested mushroom raw material), Leuconostoc mesenteroides predominated in spontaneously fermented A. bisporus, while Lactiplantibacillus paraplantarum, Lactiplantibacillus plantarum, and Lactococcus lactis were less abundant. The highest dynamics of acidification of the mushroom material were exhibited by isolates EK55 and EK4 that, after 24 h of incubation, were able to decrease the pH of the raw material up to 5.06 ± 0.021 and 5.17 ± 0.015, respectively. Furthermore, the analysis of bacterial cell hydrophobicity indicated that the highest values of this parameter were noted for L. plantarum isolates EK12 (29.59 ± 0.7%), EK55 (28.75 ± 0.551%), and EK5 (27.33 ± 1.516%). It was revealed some of the analyzed LAB (especially isolates L. plantarum EK55 and L. paraplantarum EK4) exhibited functional and technological potential that might be used in the formulation of novel starter cultures.

10.
Int J Med Mushrooms ; 21(4): 393-400, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002634

RESUMO

Water-soluble polysaccharides (WSPs) were isolated from freeze-dried and hot-air-dried fruiting bodies of five wild-growing edible species: Armillaria mellea, Lactarius deliciosus, Leccinum aurantiacum, Suillus luteus, and Boletus badius. The concentrations of WSPs ranged from 36.3 ± 0.7 mg/g dw to 105.9 ± 3.9 mg/g dw. The method of drying substantially affected the quantity of WSP. The loss of WSP depended on species and varied between ~ 19% and ~ 48%. The extracted WSP contained varied amounts of carbohydrate, protein, and phenolics. The samples exerted antioxidant properties measured with the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assay (11.5 ± 2.0 to 38.4 ± 3.6 µmol Trolox/g dw) and the Ferric reducing antioxidant power (FRAP) assay (9.1 ± 1.3 to 40.6 ± 1.4 µmol Trolox/g dw). In most cases, hot-air drying slightly increased the antioxidant potential of WSP.


Assuntos
Antioxidantes/análise , Basidiomycota/química , Dessecação/métodos , Polissacarídeos/química , Agaricales/química , Congelamento , Carpóforos/química , Temperatura Alta , Água
11.
Compr Rev Food Sci Food Saf ; 18(3): 655-669, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-33336922

RESUMO

Pickling is one of the methods for preserving food. However, this term may refer to both types of products, that is, to those subjected to lactic acid fermentation and to marinated ones (acidified) that are usually produced by the addition of acetic acid. Various raw materials are subjected to lactic acid fermentation (vegetable and animal origin), which yields food products with high nutritional and dietary value. In many regions of the world, the process of lactic fermentation is also traditionally used to preserve fruiting bodies of edible mushrooms. Mushrooms are appreciated for their organoleptic qualities as well as the presence of many different bioactive substances exhibiting healing and health-promoting properties. This article reviews the literature related to the use of lactic fermentation in the process of mushroom preservation. Particular attention has been paid to the aspects of the technological process and its impact on the quality and suitability of the final products. Moreover, research results concerning the influence of lactic fermentation on chemical and physical changes in fruiting bodies of edible fungi are also presented.

12.
Pol J Microbiol ; 67(2): 203-211, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-30015458

RESUMO

Most of the lactic acid bacteria (LAB) are able to grow in milk mainly due to the activity of a complex and well-developed proteolytic system. Cell envelope-associated proteinases (CEPs) begin casein hydrolysis and allow for releasing the peptides, enclosed in the structure of native milk proteins that are essential for growth of Lactobacillus helveticus. The biodiversity of genes encoding CEPs among L. helveticus strains can have an effect on some technological parameters such as acid production, bacterial growth rate in milk as well as liberation of biologically active peptides. The study reveals significant differences in the presence of various variants of CEPs encoding genes among ten novel Polish strains and indicates the intraspecific diversity exhibited by L. helveticus. In terms of distribution of CEPs genes, four different genetic profiles were found among the microorganisms analyzed. Furthermore, the strains exhibited also various levels of proteolytic activity. Molecular analysis revealed that prtH3 is the most abundant CEPs-encoding gene among the strains investigated. The results indicate also that ecological niche and environmental conditions might affect proteolytic properties of L. helveticus strains. The greatest variety in terms of quantity of the detected CEP encoding genes was noticed in L. helveticus 141, T105 and T104 strains. In these strains, the combination of three nucleotide gene sequences (prtH/prtH2/prtH3) was identified. Interestingly, T104 and T105 exhibited the highest proteolytic activity and also the fastest dynamic of milk acidification among the tested strains of L. helveticus.


Assuntos
Parede Celular/genética , Lactobacillus helveticus/enzimologia , Lactobacillus helveticus/genética , Peptídeo Hidrolases/genética , Animais , Proteínas de Bactérias/genética , Caseínas/metabolismo , Parede Celular/enzimologia , Hidrólise , Leite/microbiologia , Polônia , Análise de Sequência de DNA
13.
J Food Sci Technol ; 54(11): 3679-3688, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29051663

RESUMO

This paper explores the ability of Lactobacillus helveticus strains to release sequences of short biologically active peptides (containing 2-10 amino acid residues) from casein. The proteolytic enzymes of the tested strains exhibit different patterns of cleavage of CN fractions. The modification of κ-casein (κ-CN) with pyrrolidone carboxylic acid inhibits the proteolytic activity of strains L. helveticus 141 and the reference strain (DSMZ 20075), while the modification with phosphothreonine inhibits enzymes of all the tested bacteria. The peptide sequencing analysis indicated that the examined strains produced functional peptides very efficiently. κ-CN proved to be the main source of short peptides released by bacterial enzymes, and the hydrolysis of κ-CN yielded eighty-two bioactive peptides. The hydrolysis of αS2-casein, αS1-casein, and ß-casein yielded six, two, and one short-chain bioactive peptides, respectively. The isolated bioactive peptides exhibited antioxidative, opioid, stimulating, hypotensive, immunomodulating, antibacterial, and antithrombotic activities. A vast majority of the isolated bioactive peptides caused inhibition of the angiotensin-converting enzyme and dipeptidyl peptidase IV. The role of hydrolysis products as neuropeptides is also pointed out. The highest number of cleavage sites in κ-casein and functional activities of short-chain peptides were obtained in hydrolyzates produced by L. helveticus strain T105.

14.
Acta Sci Pol Technol Aliment ; 16(2): 199-207, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28703960

RESUMO

BACKGROUND: The increasing significance of food products containing substances with antioxidative activi- ties is currently being observed. This is mainly due to the fact that pathogenic changes underlying some diseases are related to the carcinogenic effects of free radicals. Antioxidative compounds play an important role in supporting and enhancing the body’s defense mechanisms, which is useful in preventing some civili- zation diseases. Unfortunately, it has been already proved that some synthetic antioxidants pose a potential risk in vivo. Therefore, antioxidant compounds derived from a natural source are extremely valuable. Milk is a source of biologically active precursors, which when enclosed in structural protein sequences are inactive. The hydrolysis process, involving bacterial proteolytic enzymes, might release biopeptides that act in various ways, including having antioxidant properties. The objective of this study was to determine the antioxidant properties of milk protein preparations fermented by Polish strains of L. helveticus. The research also focused on evaluating the dynamics of milk acidification by these strains and analyzing the textural properties of the skim milk fermented products obtained. METHODS: The research studied Polish strains of L. helveticus: B734, 141, T80 and T105, which have not yet been used industrially. The antioxidant properties of 1% (w/v) solutions of milk protein preparations (skim milk powder, caseinoglycomacropeptide and α-lactoalbumin) fermented by these strains were determined by neutralizing the free radicals with 2,2-diphenyl-1-picrylhydrazyl (DPPH˙). Moreover, solutions of skim milk powder (SMP) fermented by the microorganisms being tested were analyzed on gel electrophoresis (SDS-PAGE). The dynamics of milk acidification by these microorganisms was also analyzed L. helveticus strains were used to prepare fermented regenerated skim milk products that were subjected to texture profile analysis (TPA) performed using a TA-XT2i (Stable Micro Systems, Godalming, UK). RESULTS: The results suggest that the antioxidant activity of fermented milk protein preparations depended on the type of milk protein preparation and was also related to the strain that conducted the fermentation process. The process of caseinoglycomacropeptide (CGMP) fermentation by DSMZ 20075, T105 and 141 signifi- cantly (p < 0.05) influenced the increase in the antioxidant activities of the protein preparation, the highest values of parameter were obtained in samples fermented by L. helveticus T105 (64.82 ±0.013%), while in the case of α-lactoalbumin (α-la), the strongest free radical scavenging activity (66.67 ±0.020%) was noted for unfermented samples (control). CONCLUSIONS: The greatest increase in DPPH scavenging activity (% of inhibition) was noted for fermented SMP solutions. The highest values of the parameter measured were recorded for SMP fermented by the reference strain (85.98 ±0.009%) and T80 (81.66 ±0.013%). Strain T105 demonstrated the most desirable properties with respect to milk acidifying dynamic and texture properties of fermented skim milk products, while the reference strain (L. helveticus DSMZ 20075) and L. helveticus T80 seem to be more desirable in terms of the possibility of obtaining fermented protein preparations with the best antioxidant properties. The Polish strains analyzed here might find application in dairy products and also in developing functional food products. Furthermore, the preparations of milk protein that were fermented by the strains being tested may be a natural source dietary antioxidants.


Assuntos
Antioxidantes/farmacologia , Fermentação , Lactobacillus helveticus/metabolismo , Proteínas do Leite/farmacologia , Animais , Antioxidantes/análise , Caseínas/análise , Caseínas/farmacologia , Produtos Fermentados do Leite/microbiologia , Microbiologia de Alimentos , Alimento Funcional , Glicopeptídeos/análise , Glicopeptídeos/farmacologia , Concentração de Íons de Hidrogênio , Leite/química , Leite/microbiologia , Proteínas do Leite/análise , Polônia
15.
Food Chem ; 199: 203-9, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26775962

RESUMO

The main objective of this work was to determine the stability of vitamin D2 in dried mushrooms Agaricus bisporus, Pleurotus ostreatus and Lentinula edodes during storage, as well as to examine the possibility of inducing vitamin D2 production in dried mushrooms by UVB irradiation. After 1.5 year storage of dried mushrooms, the level of vitamin D2 in button mushrooms was found to be 6.90 µg/g dw, which is a 48.32% of initial level of vitamin D2. In the case of dried oyster and shiitake mushrooms there was a decrease to the level of 66.90% and 68.40%, respectively. It was determined that dried mushrooms can produce ergocalciferol under UVB irradiation. The highest content of vitamin D2 was observed in A. bisporus. Freeze-dried A. bisporus contained from 42.08 to 119.21 µg/g dw and hot-air dried mushrooms contained from 21.51 to 81.17 µg/g dw vitamin D2.


Assuntos
Agaricales/química , Ergocalciferóis/química , Armazenamento de Alimentos , Agaricales/metabolismo , Agaricales/efeitos da radiação , Liofilização , Humanos , Recomendações Nutricionais , Raios Ultravioleta
16.
Acta Sci Pol Technol Aliment ; 15(1): 29-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28071036

RESUMO

BACKGROUND: The intake of fermented milk products, especially yoghurts, has been systematically increasing for a few decades. The purpose of this work was to obtain milk products fermented with a mix of bacterial cultures (yoghurt bacteria and Lactobacillus acidophillus LA-5) and enriched with selected milk protein preparations. Secondly, the aim of the work was to determine physiochemical and rheological properties of the obtained products. METHODS: The following additives were applied in the experiment: whey protein concentrate (WPC 65), whey protein isolate (WPI), demineralised whey powder (SPD), caseinoglycomacropeptide (CGMP), α-lactalbumin (α-la), sodium caseinate (KNa) and calcium caseinate (KCa). Milk was fermented using probiotic strain Lactobacillus acidophillus LA-5 and a typical yoghurt culture. The products were analysed in terms of the survivability of bacterial cells during refrigerated storage, rheological properties and syneresis. Fermented milk products were obtained using blends of bacterial strains: ST-B01:Lb-12 (1:1), ST-B01:Lb-12:LA-5 (1:1:2). RESULTS: Milk beverages fermented with typical yoghurt bacteria and LA-5 strain showed intensive syneresis. The addition of LA-5 strain caused formation of harder acid gels, comparing to typical yoghurts. Milk products which were prepared from skimmed milk possessed higher values of hardness and consistency coefficient. The increase of concentrations of milk preparations (except of WPI) did not cause significant differences in the hardness of acidic gels obtained by fermentation of mixed culture with a probiotic strain. CONCLUSIONS: The applied preparations improved physiochemical properties of the milk beverages which were prepared with a probiotic strain. The increase of protein milk preparations concentration resulted in a gradual decrease of the secreted whey. Among the products that were made of full milk powder and were subjected to three weeks of refrigerated storage the highest survivability of Lb. acidophilus LA-5 was noticed in the samples fortified with 1% WPC.


Assuntos
Produtos Fermentados do Leite/microbiologia , Armazenamento de Alimentos , Lactobacillus acidophilus/crescimento & desenvolvimento , Proteínas do Leite/metabolismo , Animais , Caseínas/química , Caseínas/metabolismo , Fenômenos Químicos , Produtos Fermentados do Leite/análise , Fermentação , Alimentos em Conserva/análise , Glicopeptídeos/química , Glicopeptídeos/metabolismo , Lactalbumina/química , Lactalbumina/metabolismo , Lactobacillus acidophilus/isolamento & purificação , Lactobacillus acidophilus/metabolismo , Lactobacillus delbrueckii/crescimento & desenvolvimento , Lactobacillus delbrueckii/isolamento & purificação , Lactobacillus delbrueckii/metabolismo , Ligilactobacillus salivarius/crescimento & desenvolvimento , Ligilactobacillus salivarius/isolamento & purificação , Ligilactobacillus salivarius/metabolismo , Fenômenos Mecânicos , Leite/química , Proteínas do Leite/química , Polônia , Refrigeração , Reologia/métodos , Simbiose , Proteínas do Soro do Leite/química , Proteínas do Soro do Leite/metabolismo , Iogurte/microbiologia
17.
Acta Biochim Pol ; 62(4): 713-20, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26601325

RESUMO

Many strains belonging to lactobacilli exert a variety of beneficial health effects in humans and some of the bacteria are regarded as probiotic microorganisms. Adherence and capabilities of colonization by Lactobacillus strains of the intestinal tract is a prerequisite for probiotic strains to exhibit desired functional properties. The analysis conducted here aimed at screening strains of Lactobacillus helveticus possessing a health-promoting potential. The molecular analysis performed, revealed the presence of a slpA gene encoding the surface S-layer protein SlpA (contributing to the immunostimulatory activity of L. helveticus M 92 probiotic strain) in all B734, DSM, T80, and T105 strains. The product of gene amplification was also identified in a Bifidobacterium animalis ssp. lactis BB12 probiotic strain. SDS-PAGE of a surface protein extract demonstrated the presence of a protein with a mass of about 50 kDa in all strains, which refers to the mass of the S-layer proteins. These results are confirmed by observations carried with transmission electron microscopy, where a clearly visible S-layer was registered in all the strains analyzed. The in vitro study results obtained indicate that the strongest adhesion capacity to epithelial cells (HT-29) was demonstrated by L. helveticus B734, while coaggregation with pathogens was highly diverse among the tested strains. The percentage degree of coaggregation was increasing with the incubation time. After 5 h of incubation, the strongest ability to coaggregate with Escherichia coli was expressed by T104. The T80 strain demonstrated a significant ability to co-aggregate with Staphylococcus aureus, while DSM with Bacillus subtilis. For B734, the highest values of co-aggregation coefficient was noted in samples with Salmonella. The capability of autoaggregation, antibiotic susceptibility, resistance to increasing salt concentrations, and strain survival in simulated small intestinal juice were also analyzed.


Assuntos
Promoção da Saúde , Lactobacillus helveticus/fisiologia , Probióticos , Aderência Bacteriana , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Células HT29 , Humanos , Intestinos/microbiologia
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