Antioxidants and Natural Compounds

Oxidative stress happens in body when the production of oxidants exceeds the antioxidant capacity of body system and plays a role in pathogenesis of several chronic diseases such as diabetes, cardiovascular diseases, stock, and renal failure. Tea, sesame seed, and burdock root (Arctium lappa L.) may improve oxidative stress and suppress the side effects of diabetes, rheumatoid arthritis and osteoarthritis. Total extract of black tea and its fractions can increase antioxidants such as Super oxide Dismotase (SOD), Glutathione Peroxides (GPX) and total antioxidants and can decrease oxidants like malondialdehyde (MDA). So, these herbal compounds can improve oxidative stress in diabetes rats. The injection of total extract and 20% fraction of black tea had positive effect on blood lipid profile in diabetic rats. Sesame seeds improved the antioxidants capacity in arthritis; therefore, decreased pain. Burdock root, in arthritis patients improved the antioxidants capacity and decreased the intensity of the pain. It can be concluded that the positive effects of these herbal components are due to the presence of antioxidants. The aim of this chapter is to review the antioxidant capacity of tea, sesame seed, and burdock root as well as to discuss their biological effects in human being

Fluctuations in the Phenolic Content and Antioxidant Capacity of Nettle (Urtica dioica L.) Drink in Refrigerated Storage

The aim of this study was to analyze the total phenolic content and antioxidant activity of refrigerated nettle drinks stored at 4°C for 3 months. The antioxidant properties determined by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assays and total phenolic contents of the nettle drinks were evaluated using Folin-Ciocalteu method. In addition, correlations between antioxidant activity and total phenolic content were assessed. The results showed a significant increase for the refrigerated nettle drinks (p<0.05) in the case of total phenolic content and antioxidant activity in two months. It was concluded that the nettle drink should be treated as a short shelf-life product (2-month)

Investigating of drying kinetics and mathematical modeling of turnip

The drying process of turnip and drying rate curves were investigated at different temperatures (55, 70 and 85°C) with air flow rate of 1.5 m/s.  Also effective diffusion coefficient and activation energy were calculated by using Arrhenius equation and Fick’s second law for infinite slab.  The effective diffusivity varied between 5.471×10-10 and 8.966×10-10 in the range of (55°C to 85°C).  The value of activation energy was found to be 16.013 kJ/mol.  The mathematical models (Newton, Page, Modified Page, Henderson and Pabis, Logarithmic, Two term, Two term exponential, Wang and Singh, Simplified Fick’s diffusion, Modified Page –II, Verma, Midilli–Kucuk, Hii, Law and Cloke, Approximation of diffusion, Modified Henderson and Pabis) were fitted to the experimental data.  Sigmaplot v10.0 software was used to find the best model for evaluating the rate of moisture change.  Decency of fit by these models was based on comparing the coefficient of determination (R2), reduced chi-square (χ2), mean bias error (MBE) and root mean square error (RMSE) between the observed and predicted variables.  Among 15 evaluated models, Modified Henderson and Pabis in 85°C and Hii, Law and Cloke in 55°C and 70°C with highest R2 and lowest MBE, χ2 and RMSE were selected to better estimate the drying curves.Keywords: Turnip, hot air convective drying, modeling, drying rate, effective diffusivity, activation energ

Development of Synbiotic Milk Chocolate Enriched with Lactobacillus paracasei, D-tagatose and Galactooligosaccharide

Background and Objective: Prebiotics are food ingredients that induce the growth or activity of beneficial bacteria (Bifidobacteria and Lactobacilli). Galactooligosaccharide and tagatose are two main prebiotic compounds which are used in the food industry. Chocolate is widely consumed all over the world and could be used as an excellent vehicle for delivery of prebiotics. Furthermore, the incorporation of probiotics into chocolate, allows broadening the health claims of chocolate. The aim of the current study was to investigate the effect of tagatose and galactooligosaccharide on the physicochemical and sensory properties of milk chocolate and the survivability of Lactobacillus paracasei in the optimized formulation. Material and Methods: Probiotic milk chocolate containing Lactobacillus paracasei were formulated by replacing a portion of the sucrose with the galactooligosaccharide powder and tagatose. For this purpose various concentrations of galactooligosaccharide and tagatose (2.5, 5 and 7.5% w w-1) along with stevia were used in chocolate formulation. Nine formulations were examined to determine some physicochemical, mechanical and sensory properties in order to find the optimum concentrations of these components. The lyophilized Lactobacillus paracasei were incorporated in the optimal formulation of prebiotic milk chocolate. The viability of probiotic bacteria in milk chocolate was carried out during storage at 22°C for up to 6 months.Results and Conclusion: In general, chocolate formulations with high levels of galactooligosaccharide, achieved the highest plastic viscosity and yield stress. The lowest viscosity and yield stress were observed for the samples containing high concentrations of tagatose and in control. In addition, galactooligosaccharide at higher ratios induced the least desirable sensorial effects, whereas tagatose improved the overall acceptability. It can be concluded that the overall acceptability of milk chocolate samples were with (7.5), tagatose: galactooligosaccharide ratios of 2.5%-2.5%, presenting the optimal applicable range as prebiotic compounds. Numbers of live Lactobacillus paracasei cells remained above 8.0 log CFU g-1 until 6 months under ambient conditions. Milk chocolate was shown to be an excellent vehicle for the delivery of Lactobacillus paracasei, and the prebiotic ingredients galactooligosaccharide and tagatose did not interfere in its viability. Conflict of interest: The authors declare no conflict of interest

Effects of Adding Non-viable Lacticaseibacillus casei and Lactobacillus acidophilus on Physicochemical, Microbial, Chemical and Sensory Attributes of Probiotic Doogh

  Background and Objective: Inactivated probiotics provide various health and technological benefits, making them appropriate for the production of functional dairy products. The aim of this study was to investigate effects of adding nonviable probiotics (Lactobacillus acidophilus LA-5 and Lacticaseibacillus casei 431) to doogh (a typical Iranian fermented milk drink). Material and Methods: Probiotics were inactivated by heat or sonication and added to the samples before or after fermentation. Various parameters such as pH, titratable acidity, redox potential, antioxidant capacity, color, viscosity, and phase separation, viability of traditional starter bacteria and probiotics and sensory characteristics were assessed during fermentation and refrigerated storage at 5 °C. Results and Conclusion: Sonicated probiotic-containing treatments included the highest pH decrease rate (0.011 pH min-1) during fermentation, as well as the highest antioxidant capacity (16.45%) and viscosity (35.15 mPa.s), while heat-inactivated probiotic- containing treatments included the lowest viscosity (17.60 mPa.s). Treatments with viable probiotics reasonably included the highest post-acidification rate during storage (4.14 °D d-1), compared to those containing nonviable cells, as well as the minimum phase separation rate. The b* and L* values of color did not differ significantly within treatments, but the highest a* value was observed in the treatments with sonication. The highest populations of Lactobacillus delbrueckii ssp. bulgaricus (log 11,891 cfu ml-1) and Streptococcus thermophilus (log 14,977 cfu ml-1) at the end of the storage were observed in treatments with heated probiotics (compared to viable probiotics) and treatments with sonicated probiotics, respectively. In addition, Lactobacillus acidophilus was more susceptible than Lacticaseibacillus case and included lower viability. Taste, mouth feeling and total acceptance of all samples did not differ significantly within treatments. The present study suggests that inactivated probiotics can successfully be used for the production of fermented milk beverages with appropriate sensory characteristics and higher antioxidant capacity, compared to the control group. Conflict of interest: The authors declare no conflict of interest.   Introduction   Recently, it has been suggested that probiotics, viable or non-viable, are bacterial cells that include positive effects on human health. By this general definition, probiotics are divided into two categories of viable and non-viable probiotics [1, 2]. The idea of using non-viable probiotics in food industries is originated from the fact that probiotic bacteria are susceptible to environmental conditions during passage through the gastrointestinal tract (GIT), include limited stability over a wide range of pH and temperature, include a shorter shelf-life and need refrigerated storage. Therefore, their use in various industries is further technologically and economically feasible [3-6]. Additionally, it has been verified that non-viable probiotics include beneficial effects for humans such as immunostimulating activity [7], cholesterol decrease [8], anticancer characteristics [9], healing gastrointestinal disorders [10] and suppression of pro-inflammatory cytokine production [11]. There are several available methods to inactivate probiotics, including heat treatment, ultraviolet (UV) irradiation, irradiation, sonication (ultrasound), high pressure, ionizing radiation, pulsed electric field (PEF), supercritical CO2, drying and changes in pH [8,12]. Sonication and heating are the most commonly used methods for inactivating probiotics, majorly because they are cost-effective and time-efficient. Ultrasound at frequencies of 20–40 kHz can be lethal to microorganisms by creating acoustic cavities on their cell membrane (CM), leading to the release of their contents [13]. In contrast, during heating, intracellular contents are not released. Doogh is a fermented beverage whose major ingredients include yogurt, water, salt and flavoring agents [14]. However, studies on adding non-viable probiotics to fermented foods are limited. Parvayi et al. studied effects of inactivated Lactobacillus acidophilus ATCC SD 5221 and Bifidobacterium lactis BB-12 on yogurt characteristics and reported that incorporation of heat-inactivated probiotics to yogurts included less technological challenges and could be deliberated as an appropriate alternative for probiotics in functional yogurts [15]. Overall, there is still a research gap in the development and commercialization of inactivated probiotic dairy products in food industries. While interests in probiotics and prebiotics are increasing, inactivated probiotics have not received much attention for product development and market availability. In addition, knowledge on specific inactivated probiotic compounds in dairy products and their potential effects on human health is limited. Further research are needed to identify and characterize these compounds and assess their potential health benefits and uses in functional foods [16,17]. Moreover, there is a lack of standardized methods for the production and quality control of inactivated probiotic dairy products, which limits their widespread commercialization. Research in this area is essential to establish industry standards and guidelines for the production and commercialization of inactivated probiotic dairy products. The aim of this study was to assess effects of adding non-viable forms of Lacticaseibacillus casei 431 and lactobacillus acidophilus LA-5 probiotics inactivated by heating or sonication on the quality characteristics of doogh, a traditional fermented milk beverage from Iran. Probiotics were added before or after the milk fermentation processes. Materials and Methods Materials Skim milk powder was purchased from Pegah, Tehran, Iran. Starter culture included Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus (YF-3331) and the probiotics (Lacticaseibacillus casei 431 and Lactobacillus acidophilus LA-5) were provided by Chr. Hansen, Copenhagen, Denmark. De Man-Rogosa-Sharpe (MRS) agar and M17 agar were purchased from Quelab, Montreal, Canada, and salt from a local market. Preparation of nonviable probiotics Probiotic suspension was subjected to thermal inactivation by heating at 121 °C for 15 min [18]. To achieve ultrasound inactivation, probiotic suspension was exposed to ultrasound waves at a frequency of 250 kHz for 25 min [19]. Preparation of doogh To prepare doogh, skim milk powder was reconstituted and diluted to a total solid content of 3.5%. Mixture was heated to 90 °C and set for 15 min before cooling down to 45 °C. Probiotics in viable or nonviable form were added before heat treatment (B) or after fermentation (A). Mixture was incubated at 42 °C until the pH reached 4.5, cooled down to 5 °C and stored in refrigerator for 28 d, as presented in Fig. 1. Assessment of pH, redox potential and titratable acidity The pH, RP (redox potential) and titratable acidity of the doogh samples were checked every 30 min during fermentation. After fermentation, doogh samples were cooled and stored in refrigerator for 28 d, during which, pH, RP (redox potential) and titratable acidity were assessed every 7 d to monitor the shelf life. The pH and RP were assessed using pH meter at room temperature (RM). Titratable acidity was assessed by titrating with 0.1 M NaOH solution and 0.5% phenolphthalein indicator [20]. Increase in acidity, decrease in pH value (pH value min-1) and increase in redox potential (mV min-1) were calculated using Eqs. 1, 2 and 3: Figure 1. Study design of the present study.   Serum separation analysis After cooling down, samples were stored in 10 ml vials and incubated at 5 ºC to assess serum separation. During the shelf-life period, height of the supernatant was assessed every 7 d to assess degrees of serum separation that were expressed as proportions using the following Eq. 4 [21]:                   Eq. 4 Rheological assessment Rheological assessments were carried out using Brookfield viscometer at refrigerator temperature, one day after the samples were prepared [22]. Briefly, no. 2 cylindrical spindle and spindle speeds of 0.3, 0.6, 1.5, 3, 6, 12, 30 and 60 rpm were used during 90 s if the torque to rotate the spindle in the samples was between the 15.0 and 85.0% of the maximum torque. Assessment of antioxidant capacity To assess antioxidant capacity of the samples, a method was used based on the ability of antioxidants to scavenge the stable radical DPPH (1,1-diphenyl2-picrylhydrazyl). This method was described by Farahmandfar et al. essentially, sample ability to reduce the concentration of DPPH was assessed by measuring absorbance of the solution before and after exposure to the samples [23]. Antioxidant capacity of all samples and inactivated bacterial suspension were assessed on two occasions. The first assessment was carried out on the day of production, while the second assessment was carried out on Day 28 of the shelf-life.        Eq. 5 Color assessment Color characteristics of doogh were assessed using Hunter Lab Color Flex EZ explained by Milovanovic et al. [24]. Color parameters were L* (brightness, white = 100, black = 0), a* (+, red; -, green) and b* (+, yellow; -, blue). Bacterial enumeration Pour plate method was used to count numbers of L. delbrueckii subsp. bulgaricus, S. thermophilus and L. casei [25]. The L. bulgaricus, starter bacteria of doogh, was cultured in MRS-bile agar at 42 ºC for 72 h under anaerobic conditions using Gas Pac system. Enumeration of S. thermophilus was carried out using M17 agar at 37 ºC for 24 h under aerobic conditions [26]. Lactobacillus acidophilus LA-5 and L casei were cultured in MRS agar with added bile (0.15% w w-1) to prepare selective media of probiotic enumeration at 37 ºC for 72 h under aerobic conditions [27, 28]. The initial counts of L. acidophilus and L. casei were 107 CFU ml-1. To calculate the viability proportion index, final cell population of the microorganisms was divided into the initial cell population based on the Eq. 6 [25].                                                            Eq. 6 Sensory evaluation Taste, mouth feel and overall acceptance of doogh were assessed using 5-point hedonic scale rating test (with 5 excellent, 4 good, 3 acceptable, 2 bad and 1 very bad) [29]. Twenty consumers assessed the sensory attributes of doogh samples after the first day of preparation. Statistical analysis All experiments were carried out in triplicate and expressed as mean ±SD (standard deviation) (n = 3). Data were analyzed using univariate analysis of variance (Tukey test) AND SPSS statistical software v.26 (SPSS, Chicago, USA). Generally, p < 0.05 was addressed as the significance threshold. Results and Discussion Assessments of pH, redox potential and titratable acidity During milk fermentation, growth of starter bacteria leads to the conversion of lactose into various compounds such as lactic acid, acetate, formate, acetaldehyde and ethanol. This process results in lactic acid production, causing decreases in pH and increases in redox potential and titratable acidity [30]. Figure 2 illustrates changes in pH, redox potential and titratable acidity during the fermentation process. The initial pH of milk at the beginning of fermentation was 6.8, dropping to 4.5 by the end of fermentation. As shown in Fig. 2, and Table 1 fermentation process included three distinct phases of lag, log and constant phases. During the first 30 min, the lag phase, no significant changes were seen, possibly due to the adaptation of the starter bacteria and buffering characteristics of milk [31]. The fastest decrease in pH and increase in redox potential were observed in sample with ultrasound-inactived L. casei. This might be attributed to the ultrasound treatment, which caused puncturing of the membrane of the probiotics, resulting in the release of their cell contents into doogh [5,13]. Feeding the starter bacteria resulted in decreases in the rate of pH and pH of BUC reached 4.5 as the fastest rate (after 210 min). However, BUA included the highest titratable acidity, indicating that the type of probiotic bacteria included major effects on the rate of pH drop and acidity increase. Similarly, Tian and colleagues (2017) reported that the type of bacteria included effects on the quantification of organic acids [32]. In addition, postbiotics produced from L. acidophilus LA-5, L. casei 431 and L. salivarius included 62 vrious components, including alcohols, terpenes, norisoprenoids, acids, ketones and esters [33]. Hence, these compounds were available in the environment and might improve the fermentation stage. Based on Fig. 2, BHC included similar rates of pH decrease and increase in redox potential through the fermentation process as the sample without probiotics. However, BHA showed the lowest rate of acid increase at the end of the fermentation, indicating that the starter bacteria alone were responsible for lactic acid production and the intact cells of the probiotic bacteria included no significant effects on acid production. Furthermore, heat-inactivated L acidophilus demonstrated the antibacterial activity [34]. Samples containing live probiotics needed longer times (240 min) to reach pH 4.5. This finding was similar to the finding of Parvayi (2021), who reported that live probiotic samples needed longer times to reach pH 4.5, compared to paraprobiotic samples [15]. Based on a study by Vinderola et al. (2002), adding L. casei and L. acidophilus to the media with the starter bacteria included negative effects on the growth of the starter bacteria, resulting in decreases in lactic acid production [35]. Statistical analysis showed no significant differences in redox potential between various types of bacteria (p>0.05). However, L. acidophilus resulted in further decreases in pH and increases in titratable acidity during the storage, compared to that L. casei did (p<0.05) as represented in Table 2. These results suggested that the selection of probiotic bacteria should carefully be considered based on the specific goals of the fermentation process [36]. Throughout the storage, the highest level of titratable acidity was seen in sample containing live probiotics of L. acidophilus (181AD∘), which could be attributed to the ongoing acid production by the live probiotics at the refrigerated storage. In contrast, BUC sample included the lowest acidity (117A∘), suggesting that the addition of probiotics after the fermentation process could lead to uncontrolled increases in acidity and continued fermentation during cold storage [15]. Moreover, samples containing sonicated and live probiotics included the maximum and the minimum RP increasing rates because of producing the minimum and the maximum lactic acid quantities during storage (p<0.05). Serum separation The study detected that the activity of starter bacteria and their ability to generate acids included significant effects on the separation of serum in the samples [37]. Data of Table 3 show increases in serum separation values for all samples during the storage. The initial and the final separation rates of BUC were the highest (32.4%), suggesting that the released intracellular contents were heavier than the whole bacterial cells, causing further sedimentations. In addition, Samples containing live probiotics included smaller serum separation ratios at the end of storage, indicating that they frequently produced lactic acid and their pH was further different from the isoelectric pH [38]. Relatively, Amani et al. reported effects of the activity of starters during storage due to their protein hydrolyzing characteristics on phase separation [37]. In addition, L. casei was reported to include lower serum separation ratios than that L. acidophilus did (p<0.05). This suggested that the type of bacteria in the samples played important roles in the serum separation rate because various strains of probiotic bacteria included various abilities to ferment and break down organic compounds and producing exo-endo polysaccharides as discussed in viscosity section [39]. However, np statistically significant differences were detected between the sequences of probiotic additions (p> 0.05). Viscosity Naturally, acidification and lowering of pH during fermentation cause milk casein proteins to clump, affecting viscosity of the final products. Figure 3 shows assessed viscosity of the samples. Sonicated probiotic-containing treatments (BUC and BUA) included the highest viscosity (3.083 ±0.6 and 3.515 ±0.5, respectively). Additionally, addition of live probiotics during fermentation led to increased viscosity, compared to samples without probiotics. It was reported that the release of exopolysaccharides and intracellular polysaccharides from the probiotics significantly increased viscosity [40, 41]. Exopolysaccharides secreted by Lactobacillus spp. during their growth affect viscosity of dairy products [42]. Moreover, "intracellular polysaccharides" are polysaccharides that accumulate within cells. The intracellular biosynthetic process involves transferring sugar residues into the cell, converting them into various monomeric units, partially polymerizing them and attaching them to isoprenoid lipid carriers [43]. Viscosity of heat-inactivated treatments was similar to that of control treatment, possibly because intact cells of probiotic bacteria did not release biopolysaccharides into doogh samples. Furthermore, type of bacteria significantly affected the viscosity (p<0.05). It was previously reported that variations in the viscosity values could be affected by characteristics of the probiotics cultures as well as adaptability of the bacteria [44]. Antioxidant activity assessment The DPPH radical scavenging method, widely used to assess antioxidant activities, is simple, rapid, sensitive and reproducible compared to other methods [45]. Figure 4 shows antioxidant capacities of the samples on Days 1 and 28. Antioxidant capacity of the samples decreased significantly during the storage due to inappropriate sealing, oxygen entry into the samples and uncontrolled bacterial activity. Sonicated probiotic-containing treatments increased the antioxidant capacity, as the intracellular content of lactic acid bacteria (LAB) demonstrated greater antioxidant characteristics than that the whole cell or the extracellular metabolites did [46,47]. Antioxidant activity of the intracellular contents of LAB was linked to the activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), nicotinamide adeninedinucleotide (NADH)-oxidase, NADH-peroxide and glutathione (GSH) enzymes [48]. In addition, use of live or heat-inactivated probiotics did not result in significant differences (p>0.05). This was due to the cell contents that were not released. Relatively, lyophilized cells of Lactococcus lactis subsp. cremorishave included the highest antioxidant capacity, compared to those the heat-killed and intact cells did [49]. In contrast, use of L. acidophilus rather than L. casei significantly increased the antioxidant capacity (p<0.01). Amdekar et al. assessed antioxidant and anti-inflammatory potentials of L. casei and L. acidophilus in in-vitro models of arthritis. Results indicated that arthritic rats treated with L. acidophilus included higher glutathione peroxidase and decreased glutathione concentration, compared to that arthritic rats treated with L. casei did [50]. Additionally, adding probiotics before fermentation improved the antioxidant capacity of doogh samples (p>0.05). Color analysis   Color is a critical characteristic in assessing quality of products such as yogurts and doughs. The L* parameter indicates lightness or darkness of the color, the a* parameter shows redness or greenness of the color and the b* parameter represents yellow or blueness of the color [51]. The color values are shown in Fig. 5. Integration of probiotics inactivated using ultrasound resulted in increases in a* value, indicating release of probiotic contents into the doogh sample (p<0.05) and showing that green pigment substances such as thiamine were present in intracellular probiotics [52]. However, no significant differences were reported between the paraprobiotics and probiotics in a* value (p>0.05). Additionally, no significant differences were demonstrated between the sequential additions of probiotics in a* value (p > 0.05). Type of the probiotics in doogh samples included significant effects on a* value (p < 0.05). It has previously been suggested that various types of bacteria with special characteristics can affect color of the products [53]. In L* and b* values, no differences were observed within the addition of active/inactivated probiotics into doogh samples (p>0.05). Furthermore, types of probiotic bacteria (L. casei or L. acidophilus) and probiotic adding sequences did not include significant effects on L* and b* values (p > 0.05). Viable counts of the starter bacteria and probiotics The L. bulgaricus and S. thermophilus are critical for acidification and production of doogh [54]. Survival of the starter and probiotic bacteria in yogurts depends on various factors such as the specific strains, interactions between the species, chemical compositions of the yogurts, the culture conditions, production of hydrogen peroxide during bacterial metabolism, final acidity of the yogurts, rates of lactic and acetic acids, nutrient availability and the storage temperature [46]. Table 4 shows the number of L. delbrueckii subsp. bulgaricus and S. thermophilus for all samples during the st

EVALUATION OF SURVIVABILITY AND BIOACTIVITY OF SACCHAROMYCES CEREVISIAE IN BREAD DOUGH

One of the most significant current discussions in dough fermentation is survivability and bioactivity of Saccharomyces cerevisiae. In this study, four samples of instant dry yeast (all the yeast strains are active dry type) were evaluated by epifluorescence light microscopy using 0.2 % fluorescein diacetate. Microbial tests were carried out in order to count the number of viable cells yeast. Gasograph used to measuring CO2 produced during fermentation. Bread volume and height were assessed. Yeast (A) had the highest number of green cells (178 ± 7) due to its more bioactivity as compared to types B, C and D (P<0.05) and yeast (D) had the lowest number of green yeast cells (48 ± 8). In microbial tests, the number of viable yeast in yeast (A) was highest (15×1010 cfu‧mg-1) and in yeast (D) was the lowest (9×1010 cfu‧mg-1). In gasography yeast (A) produced the highest amount of CO2 (163 ± 2 mL CO2/3h) and in yeast (D) produced the lowest amount of CO2 (140 ± 2 mL CO2/3h). Bread (A) (that made by yeast A) had the highest volume (132 ± 1.0 cm3) and height (4.8 ± 0.3 cm) and bread (D) (that made by yeast D) had the lowest volume (102 ± 6cm3) and height (3.7 ± 0.2 cm). High survivability and bioactivity of baker’s yeast leads to more CO2 production that leads to high volume and height in bread

Folate bio-fortification of yoghurt and fermented milk: a review

International audienceAbstractFolate, an essential vitamin, plays an important role in human life for the synthesis of nucleotides, vitamins and some amino acid. This vitamin cannot be synthesized by humans and must be obtained exogenously to prevent folate deficiency, neural tube defects (NTDs) and other related diseases. Folic acid, the chemically synthesized form of folate, is used for fortification and supplementation, but it can cause adverse effects such as vitamin B12 deficiency in high intake. Therefore, novel methods to increase concentrations of naturally occurring folate in foods have grabbed the interest of researchers. The application of bacterial cultures in food fermentation is a novel strategy to increase “natural” folate levels. Dairy products, especially yoghurt, are an appropriate choice for bio-fortification of folate as they contain folate-binding protein which improves folate bioavailability. This study will review the folate production by probiotic bacteria in fermented milk based on various strains and culture conditions

Fabrication of UF-white cheese: Obtaining a different proteolysis rate, texture, and flavor via using combinations of mesophilic starter culture and Lactobacillus helveticus

The effect of using mesophilic starter culture (Lactococcus lactis ssp. lactis and Lactococcus lactis ssp. cremoris) and Lactobacillus helveticus (L. helveticus) at different ratios (100:0, 75:25, 50:50, 25:75, and 0:100) on the quality properties of UF-white cheese during 90 days of ripening was studied. The results revealed that an increase in L. helveticus ratio caused a significant decrease in the pH and total protein contents of the cheeses (p &lt; .05). No significant changes were observed in the dry matter content of the cheeses (p &gt; .05). The use of higher ratios of L. helveticus led to a noticeable increase in proteolysis and lipolysis indices in the cheeses (p &lt; .05). The cheese produced with higher ratios of L. helveticus had less storage (G′) and loss (G″) moduli compared to other cheeses. The more open structure was seen in the cheeses produced using higher ratios of L. helveticus. Regarding sensory properties, lower scores of body and texture, and higher scores of odor and flavor were assigned to the cheeses produced using higher ratios of L. helveticus. In conclusion, the use of combinations of mesophilic starter culture and L. helveticus at specific ratios (75:25 and 25:75) led to improve quality characteristics of UF-white cheese

The effect of probiotic supplementation on episiotomy wound healing among primiparous women: a triple-blind randomized clinical trial

Abstract Background Probiotics increase the defense power of immune system and accelerate the wound healing process by anti-inflammatory mechanisms at the wound site. The present study aimed at evaluating the effect of Lactobacillus casei oral supplementation on episiotomy wound healing among primiparous women. Methods This triple-blind randomized clinical trial was performed on 74 primiparous women delivered in Alzahra Hospital, Tabriz, Iran. Participants with mediolateral episiotomy (incision length equal to and less than 5 cm) were randomly assigned to the probiotic and placebo groups. The probiotic group received Lactobacillus casei 431 with 1.5 * 109 colony-forming unit /capsule once a day from the day after birth to 14 days. Wound healing as a primary outcome was measured by Redness, Edema, Ecchymosis, Discharge, Approximation and pain as a secondary outcome by the Visual Analogue Scale before discharge, 5 ± 1 and 15 ± 1 days after birth. The data were analyzed using independent t-test and repeated measures one way analysis of variance. Results The mean (standard deviation: SD) score of wound healing in the probiotic group altered from 4.91(1.86) before discharge to 1.55 (0.99) during 5 ± 1 days after birth and reached to 0.95 (0.27) during 15 ± 1 days after birth. Further, the mean (SD) score of wound healing in the placebo group altered from 4.62 (1.99) before discharge to 2.80 (1.20) during 5 ± 1 days after birth and reached to 1.45(0.71) during 15 ± 1 days after birth (adjusted mean difference: -0.50, confidence interval 95%: -0.96 to -0.05, P = 0.03). Conclusion Lactobacillus casei oral supplementation is effective in healing episiotomy wounds. It is suggested to evaluate the effect of topical use of Lactobacillus casei on episiotomy repair and pain in further studies. Trial registration Iranian Registry of Clinical Trials (IRCT): IRCT20170506033834N7. Date of registration: 11/08/2021