48 research outputs found
The Relationship Between Protein Fractions of Wheat Gluten and the Quality of Ring-Shaped Rolls Evaluated by the Echolocation Method
This paper presents the results of the relationship between separate protein fractions and the quality of baked ring-shaped rolls. The qualitative and quantitative protein composition of flour derived from some wheat varieties grown in Lithuania has been determined. The protein properties are evaluated by SDS-PAGE. A new method of the analysis of swelling, based on the principle of echolocation, has been used to determine the quality of this specific kind of baked goods. For the application of this method the wheat flour, which is most suitable for the production of ring-shaped rolls, made from the wheat variety Portal (Pasvalys PVRS), has been selected. This flour has the following quality parameters: proteins 10.5 %, gluten 22.0 %, gluten index 47 r.u. Correlation between the flour quality parameters and the quality of the final bread product shows that γ-gliadins (r=–0.63), LMM glutenins (r=0.55), HMM glutenins (r=0.63) and the content of gluten (r=0.87) have the greatest influence on the quality of the ring-shaped rolls
Utjecaj novih fermentiranih proizvoda, koji sadržavaju ekstrudiranu pšenicu, na kakvoću pšeničnoga kruha
Lactobacillus sakei MI806, Pediococcus pentosaceus MI810 and Pediococcus acidilactici MI807, able to produce bacteriocin-like inhibitory substances, were originally isolated from Lithuanian spontaneous rye sourdough and adapted in the novel fermentation medium containing extruded wheat material. The novel fermented products (50 and 65 % moisture content) were stored at the temperatures used in bakeries (15 days at 30–35 °C in the summer period or 20 days under refrigeration conditions at 0–6 °C). The number of lactic acid bacteria (LAB) was determined during the storage of fermented products for 15–20 days. Furthermore, the effect of novel fermented products stored under different conditions on wheat bread quality was examined. Extruded wheat material was found to have a higher positive effect on LAB growth compared to the control medium by lowering the reduction of LAB populations in fermented products with the extension of storage time and increase of temperature. During storage, lower variation and lower decrease in LAB count were measured in the novel fermented products with a moisture content of 65 % compared to those with 50 %. Furthermore, this humidity allows for the production of a product with higher moisture content in continuous production processes. The addition of the new fermented products with 65 % humidity to the wheat bread recipe (10 % of the quantity of flour) had a significant effect on bread quality: it increased the acidity of the crumb and specific volume of the bread, and decreased the fractal dimension of the crumb pores and crumb firmness. Based on the microbiological investigations of fermented products during storage and baking tests, the conditions of LAB cultivation in novel fermentation media were optimized (time of cultivation approx. 20 days at 0–6 °C and approx. 10 days at 30–35 °C).Lactobacillus sakei MI806, Pediococcus pentosaceus MI810 i Pediococcus acidilactici MI807, bakterije koje proizvode inhibitore slične bakteriocinu, izolirane su iz litvanskoga kiselog tijesta što se proizvodi od raženoga brašna, te prilagođene za uporabu u novoj fermentacijskoj podlozi s ekstrudiranom pšenicom. Da bi se ispitala mogućnost njihove primjene u pekarama, ti novi fermentirani proizvodi (s 50 i 65 % vlažnosti) skladišteni su 15 dana pri ljetnim temperaturama od 30 do 35 °C i 20 dana u hladnjaku pri 0 do 6 °C. Tijekom tih 15 do 20 dana ispitivan je broj mliječno-kiselih bakterija u fermentiranim proizvodima, te njihov utjecaj na kakvoću kruha. Dodatak ekstrudirane pšenice bitno je utjecao na rast mliječno-kiselih bakterija, u usporedbi s kontrolnom podlogom, smanjujući njihovo odumiranje u fermentiranim proizvodima tijekom duljeg skladištenja pri povišenoj temperaturi. Tijekom skladištenja primijećene su manje promjene broja mliječno-kiselih bakterija u novim fermentiranim proizvodima sa 65 % vlažnosti nego u onima s 50 % vlažnosti, pa je zaključeno da se njihovim dodatkom u kontinuiranom procesu može proizvesti kruh s većim udjelom vlage. Dodatak 10 % novih fermentiranih proizvoda sa 65 % vlažnosti pšeničnom brašnu bitno je utjecao na kakvoću kruha: povećali su se kiselost krušnih mrvica i specifični volumen kruha, a smanjila fraktalna dimenzija pora te čvrstoća mrvica. Na osnovi mikrobioloških istraživanja fermentiranih proizvoda tijekom skladištenja te pokusnog pečenja kruha optimirani su uvjeti uzgoja mliječno-kiselih bakterija u novim fermentiranim proizvodima (optimalno vrijeme uzgoja bilo je otprilike 20 dana pri 0-6 °C i 10 dana pri 30-35 °C)
Poboljšanje kakvoće mljevenog mesa dodatkom praha rajčice fermentiranog s pomoću bakterija Pediococcus pentosaceus i Lactobacillus sakei
In this study, the infl uence of lactic acid fermentation on the quality of tomato powder was evaluated. The eff ect of adding fermented tomato powder to ready-to-cook minced pork meat to improve its nutritional value and sensory characteristics was also analysed. The cell growth of Lactobacillus sakei (7.53 log CFU/g) was more intense in the medium containing tomato powder, compared to the growth of Pediococcus pentosaceus (6.35 log CFU/g) during 24 h of fermentation; however, higher acidity (pH=4.1) was observed in the tomato powder samples fermented with Pediococcus pentosaceus. The spontaneous fermentation of tomato powder reduced cell growth by 38 % and pH values slightly increased to 4.17, compared to the fermentation with pure LAB. The lactofermentation of tomato powder increased the average β-carotene and lycopene mass fractions by 43.9 and 50.2 %, respectively, compared with the nonfermented samples. Lycopene and β-carotene contents in the ready-to-cook minced pork meat were proportional to the added tomato powder (10 and 30 %). Aft er cooking, β-carotene and lycopene contents decreased, on average, by 24.2 and 41.2 %, respectively. The highest loss (up to 49.2 %) of carotenoids was found in samples with 30 % nonfermented tomato powder. Tomato powder fermented with 10 % Lactobacillus sakei KTU05-6 can be recommended as both a colouring agent and a source of lycopene in the preparation of ready-to-cook minced pork meat.U ovom je radu ispitan utjecaj mliječno-kiselog vrenja na kakvoću praha rajčice, te utjecaj dodatka fermentiranog praha rajčice na poboljšanje kakvoće, hranjive vrijednosti i senzorskih svojstava mljevenog svinjskog mesa. U podlozi je s dodatkom praha rajčice tijekom 24 sata fermentacije zamijećen veći rast stanica bakterije Lactobacillus sakei (7,53 log CFU/g) od onog Pediococcus pentosaceus (6,35 log CFU/g). Međutim, u podlozi s dodatkom praha rajčice fermentiranoj s pomoću P. pentosaceus izmjerena je veća kiselost (pH=4.1). Spontanom je fermentacijom praha rajčice rast stanica smanjen za 38 %, a pH-vrijednost je bila neznatno veća (4,17) od one uzoraka fermentiranih s pomoću čiste kulture bakterija mliječno-kiselog vrenja. Osim toga, povećani su prosječni maseni udjeli β-karotena za 43,9 i likopena za 50,2 %. Udjel je β-karotena i likopena u mljevenom svinjskom mesu bio proporcionalan masenom udjelu dodanog praha (10 i 30 %), a nakon kuhanja se smanjio za 24,2 odnosno 41,2 %. Najveći je gubitak (do 49,2 %) karotenoida zabilježen u uzorcima s 30 % nefermentiranog praha rajčice. Zaključeno je da se prah rajčice fermentiran s pomoću 10 % Lactobacillus sakei KTU05-6 može upotrijebiti kao bojilo i izvor likopena u mljevenom svinjskom mesu
Ovisnost količine lignana, dobivene in vitro fermentacijom, o udjelu neškrobnih polisaharida u žitaricama
Recently special attention has been paid to dietary fibre-associated phytoestrogens such as plant lignans, which are related to the prevention of different hormone-dependent diseases. Therefore, phytoestrogens associated with dietary fibre and their metabolites are of interest for investigation. The aim of this work is to investigate the formation of enterolignans: enterolactone (ENL) and enterodiol (END) from their precursors by the action of intestinal microflora and their relationship with non-starch polysaccharides (NSP) in various cereal products from wheat, rye, barley and oats. For the investigation of the bioconversion of plant lignans, a technique of in vitro fermentation was used and the quantitative analysis of their metabolites ENL and END was performed by high-performance liquid chromatography (HPLC) with coulometric electrode array detection. The enterolignan formation in various cereal products ranged from 78.3 to 321.9 nmol/g depending on the product type: END from 8.7 to 149.3 nmol/g and ENL from 64.4 to 278.3 nmol/g. The lignan production in bran was about two times higher than that in whole flour of the same kind of cereals. Close correlations were found between the total NSP content and the total amount of enterolignans and ENL; between pentoses and the total amount of enterolignans and ENL; between arabinose or xylose and ENL; and between galactose and END values. Considering the correlations between hexoses and END as well as between pentoses and ENL found in cereals, it can be assumed that pentoses are closely related to the quantities of plant lignans in cereal products and their conversion to enterolignans.U posljednje se vrijeme sve više pozornosti posvećuje istraživanju lignana, tj. prehrambenih biljnih vlakana bogatih fitoestrogenima, koja sprečavaju razvoj različitih bolesti uzrokovanih hormonskim poremećajem. U radu su istraženi fitoestrogeni iz prehrambenih biljnih vlakana te njihovi derivati. Svrha je rada bila utvrditi ovisnost količine enterolignana, nastalih iz njihovih prekurzora pod utjecajem crijevne mikroflore, i to enterolaktona i enterodiola, o udjelu neškrobnih polisaharida u različitim žitaricama (pšenica, raž, ječam i zob). Pritom je provedena in vitro fermentacija žitarica, a nastali enterolaktoni i enterodioli kvantitativno su određeni pomoću visokodjelotvorne tekućinske kromatografije (HPLC) s kulometrijskim detektorom. Količina se lignana u raznim proizvodima od žitarica razlikovala od 78,3 do 321,9 nmol/g, i to od 8,7 do 149,3 nmol/g enterodiola i od 64,4 do 278,3 nmol/g enterolignana. Utvrđeno je da je količina lignana u mekinjama dvaput veća od one u integralnom brašnu. Ustanovljena je neposredna ovisnost udjela neškrobnih polisaharida o količini enterolignana i enterolaktona, zatim udjela pentoza o količini enterolignana i enterolaktona, udjela arabinoze ili ksiloze o količini enterolaktona, te udjela galaktoze o količini enterodiola. Dobiveni rezultati pokazuju da količina lignana u proizvodima od žitarica ovisi o udjelu pentoza i njihovoj konverziji u enterolignane
The Use of Lactic Acid Bacteria in the Fermentation of Fruits and Vegetables — Technological and Functional Properties
Fermentation Processes Using Lactic Acid Bacteria Producing Bacteriocins for Preservation and Improving Functional Properties of Food Products
Non-alcoholic beverages from fermented cereals with increased oligosaccharide content
The aim of this study is to develop a new technology for making traditional Lithuanian non-alcoholic beverage kvass from fermented cereals by extending the spectrum of raw materials (extruded rye) and applying new biotechnological resources (xylanolytic enzymes and lactic acid bacteria (LAB)) to improve its functional properties. Arabinoxylans in extruded rye were very efficiently hydrolysed into oligosaccharides by xylanolytic complex Ceremix Plus MG. Using Ceremix Plus MG and LAB fermentation, the yield of arabinoxylooligosaccharides and xylooligosaccharides in beverage was increased to 300 and 1100 mg/L, respectively. Beverages fermented by LAB had lower pH values and ethanol volume fraction compared to the yeast fermented beverage. The acceptability of the beverage fermented by Lactobacillus sakei was higher than of Pediococcus pentosaceus- or yeast-fermented beverages and similar to the acceptability of commercial kvass made from malt extract. The results showed that extruded rye, xylanolytic enzymes and LAB can be used for production of novel and safe high-value non-alcoholic beverages.Peer reviewe
Utjecaj mliječno-kiselog vrenja rajčice na omjer cis/trans izomera likopena i udjele β-karotena te L(+)- i D(-)-mliječne kiseline
Fermentation of tomato pulp by the bacteriocin-producing lactic acid bacteria (Lactobacillus sakei KTU05-6, Pediococcus acidilactici KTU05-7 and Pediococcus pentosaceus KTU05-8) was applied as a preservation method for the production of tomato products. The changes in L- and D-lactic acid contents during fermentation of different tomato varieties (Ronaldo and Cunero) were analysed. Additionally, the effects of lacto-fermentation on the cis/trans lycopene ratio, β-carotene content, and their relation to colour characteristics of fermented tomato products were investigated. Mass fractions of L- and D-lactic acid in the fermented tomato products varied from (4.25±0.04) to (7.19±0.08) mg per 100 g, and from (4.05±0.05) to (6.34±0.04) mg per 100 g, respectively. Fermentation with P. acidilactici or L. sakei culture resulted in the the decrease of D-lactic acid content by 43.6 and 37.7 %, respectively, compared to spontaneous fermentation. The fermentation with P. pentosaceus or L. sakei increased the content of lycopene on average from 3.70 to 5.68 mg per 100 g, and β-carotene from 0.89 mg per 100 g (in Cunero var.) and from 0.28 mg per 100 g (in Ronaldo var.) to 1.14 mg per 100 g. Fermentation of tomato with selected lactic acid bacteria resulted in a greater lycopene bioavailability accompanied by an increase in cis-lycopene isomer content.Fermentacijom pulpe rajčice s pomoću bakterija mliječno-kiselog vrenja koje proizvode bakteriocin (Lactobaccilus sakei KTU05-6, Pediococcus acidilactici KTU05-7 i Pediococcus pentosaceus KTU05-8) produljen je rok valjanosti proizvoda od rajčica. Određeni su udjeli L- i D-mliječne kiseline tijekom fermentacije dvaju sorata rajčice (Ronaldo i Cunero). Osim toga, ispitan je i utjecaj mliječno-kiselog vrenja na omjer cis/trans likopena i udjel β-karotena, te boju fermentiranih proizvoda. Udjel L-mliječne kiseline u 100 g fermentiranih proizvoda rajčice bio je u rasponu od (4.25±0.04) do (7.19±0.08) mg, a D-mliječne kiseline u rasponu od (4.05±0.05) do (6.34±0.04) mg. U usporedbi sa spontanom fermentacijom, udjel se D-mliječne kiseline nakon fermentacije s pomoću bakterije P. acidilactici smanjio za 43,6 %, a nakon fermentacije s pomoću bakterije L. sakei za 37,7 %. Fermentacijom s pomoću bakterije P. pentosaceus ili L. sakei povećao se udjel likopena u 100 g proizvoda, prosječno u rasponu od 3,70 do 5,68 mg, te β-karotena od 0,89 mg u sorti Cunero i 0,28 mg u sorti Ronaldo na 1,14 mg u 100 g. Fermentacijom rajčice s odabranim bakterijama mliječno-kiselog vrenja povećan je udjel iskoristivog likopena te cis-izomera likopena