Characterization of Probiotic Fermented Milk Prepared by Different Inoculation Size of Mesophilic and Thermophilic Lactic Acid Bacteria

Background and Objectives: Importance of development of novel probiotic fermented milk and challenge made for its acceptability is well known. In this research, the impact of different inoculation sizes of yogurt and DL-type starter culture (mesophilic and thermophilic LAB) on titratable acidity, viscosity, sensorial and microbial properties of fermented milk was investigated; and finally, probiotic Langfil was produced.Materials and Methods: Fermented milk produced by 1, 2 and 3% v v-1 inocula consisting thermophilic: mesophilic starter cultures 10:90 (Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. cremoris, Lactococcus lactis subsp. lactis, Lactococcus lactis subsp. lactis biovar. diacetylactis and Leuconostoc mesenteroides subsp. cremoris. Streptococcus thermophilus and Lactobacillus delbrueckii subsp. Bulgaricus) were analyzed for determination of titratable acidity, viscosity, viability of mesophilic starter cultures and sensory properties on days 5, 10, and 15 of storage at 4°C. Then, the most suitable treatments were selected for the producing probiotic Langfil, containing probiotic starter culture (2% v v-1 inoculums with equal ratio of Lactobacillus acidophilus and Bifidobacterium bifidum. Lactococcus lactis and L. cremoris were counted on M17 agar, while Leuconostoc and Lactobacillus were counted aerobically on tomato juice agar and MRS bile agar, respectively. Bifidobacterium was cultured anaerobically on MRS bile agar. Sensory evaluation was carried out by ten trained panelists, based on a nine-point hedonic scale during the cold storage.Results and Conclusion: According to results, the best organoleptic properties were achieved in the product prepared with 2% the mesophilic and thermophilic starter cultures and 2% probiotic. This product had a high viscosity. An Iranian probiotic Langfil with desired properties was produced using the best treatment prepared.Conflict of interests: The authors declare no conflict of interest

Viability of Starter Bacteria and Anti-Oxidative Activity of a Functional Yogurt Containing Silybum marianum Seed Extract

Background and objective: Silybum marianum seed extract (silymarin) is rich in phenolic compounds with anti-oxidative activity that add beneficial and healthful properties to silymarin-enriched products. The present study investigated effects of silymarin on characteristics of a functional yogurt. Material and methods: In this study, yogurt was enriched with Silybum marianum seed extract at concentrations of 0, 25, 50 and 100 mg l-1 milk and the samples were analyzed for physicochemical and sensory properties and viability of starter bacteria during 21 days at 4°C at 7-day intervals. Results and conclusion: Results showed that increasing silymarin proportion in yogurt samples increased anti-oxidative activity, total phenolic content, total viability of Lactobacillus delbrueckii and decreased pH value, viscosity and sensory attributes (p<0.05). Furthermore, pH, viscosity, anti-oxidative activity, phenolic compounds and sensory attributes decreased during storage (P<0.05). In conclusion, 25 mg Silybum marianum seed extract per one liter of milk can be used for the preparation of yogurts with healthy properties. Conflict of interest: The authors declare no conflict of interest

Karakterizacija jogurta s dodatkom Lacticaseibacillus rhamnosus kao protektivne kulture protiv kvasaca i plijesni

Lactic acid bacteria (LAB) play a very important role as natural bio-preservatives in foods. Accordingly, the inhibitory effect of Lactobacillus rhamnosus (L. rhamnosus) on 4 fungi species of Yarrowia, Penicillium expansum (P. expansum), Saccharomyces cerevisiae (S. cerevisiae), Aspergillus niger (A. niger), Kluyveromyces lactis (K. lactis) was investigated. Then P. expansum was selected as the most important contaminant mould in yoghurt to study the use of L. rhamnosus to reduce selective spoilage of P. expansum in yoghurt. Also, the effect of this bioprotective culture on the count of starter bacteria and some characteristics of yoghurt was determined. L. rhamnosus (106 cfu /mL) was inoculated into the milk along with yoghurt starter bacteria, so that four samples were produced T0 (L. rhamnosus = 0, P. expansum = 0), T1 (L. rhamnosus = 106 cfu/mL, P. expansum = 0), T2 (L. rhamnosus = 0, P. expansum = 105cfu/mL); T3 (L. rhamnosus = 106 cfu/mL, P. expansum = 105cfu/mL). All samples were analysed for pH, acidity, viscosity, syneresis, microbial (survival of Streptococcus thermophilus and Lactobacillus bulgaricus and P. expansum) and overall acceptability. L. rhamnosus had an inhibitory effect on the survival of P. expansum (p<0.05) but was not able to completely control it. L. rhamnosus in T3 sample had an inhibitory effect from the first day to the end of storage. Furthermore, during the storage, the survival of yoghurt starter bacteria in probiotic yoghurt samples was higher than the control (p<0.05). T3 had lower pH, viscosity and overall acceptability score compared to the control and its syneresis was higher (p<0.05). In general, the addition of 106 cfu/mL of L. rhamnosus did not have a complete inhibitory effect on P. expansum (105 CFU/mL) until the end of storage time.Bakterije mliječne kiseline (BMK) igraju vrlo važnu ulogu kao prirodni biokonzervansi u hrani. Prema tome, istražen je inhibicijski učinak Lactobacillus rhamnosus (L. rhamnosus) prema 4 vrste Yarrowia kvasaca i plijesni: Penicillium expansum (P. expansum), Saccharomyces cerevisiae (S. cerevisiae), Aspergillus niger (A. niger), Kluyveromyces lactis (K. lactis). Zatim je P. expansum odabran kao najvažniji kontaminant iz roda plijesni u jogurtu kako bi se istražila upotreba L. rhamnosus za selektivno smanjenje kvarenja jogurta uzrokovanog navedenim sojem plijesni. Također je određivan učinak ove biozaštitne kulture na broj starter bakterija i neke karakteristike jogurta. L. rhamnosus (106 cfu/mL) inokuliran je u mlijeko zajedno s jogurtnom starter kulturom pri čemu su proizvedena četiri uzorka T0 (L. rhamnosus = 0, P. expansum = 0), T1 (L. rhamnosus = 106 cfu/mL, P. expansum = 0), T2 (L. rhamnosus = 0, P. expansum = 105 cfu). /mL); T3 (L. rhamnosus = 106 cfu/mL, P. expansum = 105 cfu/mL). U svim uzorcima je određivana pH vrijednost, viskoznost, sinereza, mikrobiološki parametri tj. preživljavanje Streptococcus thermophilus, Lactobacillus bulgaricus i P. expansum, te ukupna prihvatljivost. L. rhamnosus je inhibiraio preživljavanje P. expansum (p<0,05), ali ga nije mogao u potpunosti kontrolirati. L. rhamnosus je u uzorku T3 pokazao jak inhibicijski učinak od prvog dana do kraja skladištenja. Nadalje, tijekom skladištenja preživljavanje sojeva jogurtne starter kulture u uzorcima probiotičkog jogurta bilo je veće od kontrolnog (p<0,05). T3 je imao niži pH, viskoznost i ukupni rezultat prihvatljivosti u usporedbi s kontrolnim uzorkom, a sinereza mu je bila viša (p<0,05). Općenito, dodavanje 106 cfu/mL L. rhamnosus nije u potpunosti inhibiralo rast soja P. expansum (105 CFU/mL) tijekom perioda skladištenja jogurta

The effect of homogenization on texture of reduced dry matter processed cheese

Abstract Since the cost of processed cheese is high in Iran, in this research we studied the effect of homogenization at the pressures of 100, 150 and 200 bar on the quality and texture of processed cheese followed by reducing dry matter. Results showed no significant difference between the pH and dry matter of processed cheese samples at different pressures (p > 0.05). Also, different pressures of homogenization had no significant effect on overall acceptability (p > 0.05). With increasing homogenization pressure, texture improved significantly (p < 0.05). Homogenization treatment at the pressure of 200 bar had the highest influence on the improvement of the processed cheese texture

The effect of homogenization on texture of reduced dry matter processed cheese

<div><p>Abstract Since the cost of processed cheese is high in Iran, in this research we studied the effect of homogenization at the pressures of 100, 150 and 200 bar on the quality and texture of processed cheese followed by reducing dry matter. Results showed no significant difference between the pH and dry matter of processed cheese samples at different pressures (p > 0.05). Also, different pressures of homogenization had no significant effect on overall acceptability (p > 0.05). With increasing homogenization pressure, texture improved significantly (p < 0.05). Homogenization treatment at the pressure of 200 bar had the highest influence on the improvement of the processed cheese texture.</p></div

Preživljavanje soja Lacticaseibacillus paracasei u ultrafiltiriranom siru u salamuri pakiranom u modificiranoj atmosferi i fleksibilnim višeslojnim filmovima

In this study, two packaging materials, modified polypropylene (MPP) and polyethylene terephthalate/aluminum/ low-density polyethylene (PETFA-Al-LDPE) were studied under various atmospheric conditions: 100% CO2, 70% N2 - 30% CO2, 80% N2 - 20% CO2 for packing probiotic ultrafiltered (UF) white brined cheese. pH, titratable acidity, moisture content, Lacticaseibacillus paracasei viability and overall acceptability were monitored within a 12-week period. The control samples were packaged in atmospheric air. Results revealed that samples packaged in PETFA-Al-LDPE with the combination of 70% N2 - 30% CO2 had the lowest pH, highest acidity and moisture content. The viability of Lacticaseibacillus paracasei was reported to be 4*106 CFU/g within 12 weeks. The highest and lowest overall acceptability was for the cheese packaged in 70% N2 - 30% CO2 and the control sample, respectively.U ovom istraživanju je ispitivana mogućnost primjene dvaju ambalažnih materijala - modificiranog polipropilena (MPP) i polietilen tereftalata/aluminij/polietilen niske gustoće (PETFA-Al-LDPE) u različitim uvjetima modificirane atmosfere (100 % CO2, 70 % N2 – 30 % CO2, 80 % N2 - 20 % CO2) za pakiranje probiotičkog sira iz salamure proizvedenog iz ultrafiltriranog (UF) mlijeka. Tijekom 12 tjedana čuvanja uzorcima sira su određivani pH, titracijska kiselost, sadržaj vlage, preživljavanje soja Lacticaseibacillus paracasei i prihvatljivost. Kontrolni uzorci su pakirani u normalnoj atmosferi (zrak). Dobiveni rezutati ukazuju kako uzorci pakirani u PETFA-Al-LDPE i modificiranoj atmosferi 70 % N2 - 30 % CO2 imaju najniži pH, te najveću kiselost i sadržaj vlage. Preživljavanje soja Lacticaseibacillus paracasei je bilo oko 4x106 CFU/g tijekom 12 tjedana. Najnižu i najvišu prihvatljivost su imali uzorak pakiran u atmosferi 70% N2 - 30 % CO2 te kontrolni uzorak

Improving the microbial quality and sensory properties of pasteurized sweet cream butter during refrigerated storage using chia seed ethanolic extract

Butter is a perishable food, and its microbial deterioration occurs in refrigeration conditions, leading to a reduction in shelf life and a loss of sensory properties. This study aimed to investigate the effect of chia seed extract (CSE) on the microbial and sensory properties of pasteurized sweet cream butter at 2°C. Ethanolic extract of chia seeds was prepared and added to the butter samples in concentrations of 0.05%, 0.1%, 0.25%, and 0.5% (v/w), and its effects on microbiological and sensory quality were evaluated at 15-day intervals during 60-day refrigerated storage. The results indicated that the addition of 0.25% and 0.5% CSE to butter treatments decreased total viable counts by 0.25–0.6 log CFU/g, total psychrotrophic counts by 1–1.5 log CFU/g, and coliform counts by 3–4 log CFU/g compared to the control sample on days 45 and 60 of storage. Moreover, concentrations of 0.1%–0.5% CSE reduced mold and yeast counts by 1.5–2.6 log CFU/g on days 30–60 of storage compared to the control sample. Escherichia coli and Staphylococcus aureus were not detected in any samples during storage. CSE had a significant effect on the sensory properties (except for aroma) of the butter samples during the 60-day storage. The best color, flavor, and overall acceptance scores were assigned to the treatments containing 0.1%–0.5% CSE compared to the control sample. It could be concluded that adding 0.1% and 0.25% CSE to refrigerated and pasteurized butter can retard microbial spoilage and improve its sensory properties at the same time

Canola meal phenolic compounds electrosprayed into capsules to increase the oxidative stability of canola oil

Abstract Nano-encapsulation is a developing area of study across several fields, including the food, pharmaceutical, and cosmetic sectors. In this study, nanocapsules containing polyphenols were made from canola meal by electrospraying, and it was determined how the capsules' walls affected their shape, encapsulation efficiency, ζ-potential, and particle size. Furthermore, the impact of nanocapsules on canola oil was examined using the TBA index, oxidative stability, and iodine value. Our findings demonstrated that spherical nanoparticles were produced using electrospraying, and that the amount of wall materials used to create them had an impact on their size. Maltodextrin/β-cyclodextrin at a ratio of 1:1 resulted in the smallest capsule sizes, with an encapsulation efficiency of 68% and an 80% release over 40 days at ambient temperature. The ζ-potential of each particle was negative. With a PDI of 0.074–0.650 and a mean size of 232.3–659.8 nm, the population of electrosprayed nanoparticles was found to be heterogeneous. By increasing nanocapsules of polyphenols to the canola oil, the oil stability and oil quality were increased. Our results showed that 800 ppm of polyphenols can improve the oil stability similarly to TBHQ, and therefore it is possible to use canola meal polyphenols as natural antioxidants in the oil industry. Graphical Abstrac