Moringa extract enhances the fermentative, textural, and bioactive properties of yogurt

The Effect of Lactiplantibacillus plantarum SHY130 and Konjac Glucomannan on the Physicochemical, Antioxidant, and Sensory Properties of Stirred Yogurt

The impact of konjac glucomannan (KGM)-based synbiotics on yogurt quality is not well understood. This study investigated the effects of a synbiotic mixture of KGM and the selected probiotic Lactiplantibacillus plantarum SHY130 on the physicochemical, antioxidant, and sensory properties of yogurt. The results showed that KGM significantly promoted the growth of Lactiplantibacillus plantarum SHY130. The synbiotics dramatically enhanced the count of lactic acid bacteria in yogurt during the 14 days of storage. Texture analysis indicated that the synbiotic supplement had no impact on springiness and cohesiveness but resulted in notable reductions in hardness, gumminess, and chewiness. The synbiotics did not significantly affect the water-holding capacity and syneresis. While the synbiotics initially decreased yogurt viscosity, it increased with storage time. Furthermore, the synbiotics significantly improved the yogurt's antioxidant capacity. Additionally, the supplementation of the synbiotics did not adversely affect sensory properties, although the synbiotics containing 0.02% KGM negatively impacted overall acceptability. Overall, these findings elucidate the effects of KGM-based synbiotics on yogurt quality, providing a foundation for developing novel synbiotic yogurt products.

Production and Evaluation of Set-Type Yoghurt Fortified with Chlorella vulgaris and Moringa oleifera Powder

Considering the growing popularity of functional foods, fortifying yoghurt with natural ingredients with various flavours and appearances could improve its nutritional and health potential. The current study aimed to evaluate the effect of Chlorella vulgaris (0.3 and 0.5%) and Moringa oleifera (0.3 and 0.5%) on the fermentation kinetics, apparent viscosity, antioxidant activity, microbiological, sensorial, and FTIR properties of yoghurt during storage. The results demonstrated that the incorporation of Chlorella vulgaris and Moringa oleifera into yoghurt increased acidification rate and decreased fermentation time (p < 0.05). Moringa oleifera (0.5%) improved the growth and survival of lactic acid bacteria as well as the phenolic and antioxidant properties of yoghurt. However, Chlorella vulgaris, at a concentration of 0.5% reduced the viability of lactic acid bacteria, viscosity, total phenolic, and antioxidant properties of yoghurt. In conclusion, it was found that Chlorella vulgaris, at 0.3%, and Moringa oleifera improved the phenolic, antioxidant properties, and acidification rate of yoghurt.

Fortified chocolate mousse with powder and extract from Moringa oleifera leaves for nutritional value improvement

This study focuses on the characterisation and incorporation of Moringa oleifera leaf powder (MOP) from Luanda (Angola) and its extract (MOE) in fortified chocolate mousse. Dark green (DG) leaves presented superior nutritional values compared to other leaves. DG contained a higher concentration of mineral salts (10 ± 1 mg/100 g of dry leaves), phenolic compounds (267 ± 4 mg GAE/g), vitamins (1.9 ± 0.2 mg/g of dry extract) and strong antioxidant capacity (IC50, 115 ± 8 µg/mL). Therefore, DG leaves were used to fortify the chocolate mousse. The leaves were prepared in three samples: control, 2 % MOP (w/w) and 2 % MOE (v/v). Textural and rheological analysis of chocolate mousse samples revealed a pseudoplastic profile for all samples, with decreased texture attributes and viscosity due to the incorporation. The sensory evaluation demonstrated that MOP and MOE samples presented 93 % and 88 % resemblance to the original product regarding general acceptance, respectively.

Enhancement of yogurt functionality by adding Mentha piprita phenolic extract and evaluation of its quality during cold storage

New functional food products with health benefits are currently in high demand among health-conscious consumers. The present research aims to improve the functional properties of yogurt by adding peppermint hydroethanolic extract (PHE) at different doses. The impact of PHE (0%, 2%, 4%, and 6%) on yogurt was studied for acidity, pH, organoleptic quality, antioxidant activity, lipid peroxidation, and fatty acid profile. The results revealed that PHE is rich in phenolic compounds, of which rosmarinic acid was the main one (339.88 mg/g lyophilized extract) and has considerable antioxidant potential, which remarkably (p < .01) increased antioxidant capacity in yogurt by over 39.51%, even at a low dose of 2%, giving the product better protection against lipid peroxidation and preserving its physicochemical and sensory quality. At 4%, PHE increased significantly (p < .01) the content of omega-3 fatty acids, notably alpha-linolenic acid, in fortified yogurt compared with the control, and reduced (p < .01) the ratio of omega-6/omega-3, which dropped from 5.21 to 4.11. It looks feasible to prepare a yogurt with health-giving properties by adding Mentha piperita hydroethanolic extract at a concentration of up to 4% as an alternative to synthetic antioxidants, which would also extend its shelf life.

Effect of freeze-dried protectants on the survival rate and fermentation performance of fermented milk's directed vat set starters

A directed vat set (DVS) starter was proposed to improve the drawbacks of liquid starters in fermented production and enhance the survival rates of B. animalis subsp. lactis BZ11, S. thermophilus Q-1, and Lactiplantibacillus plantarum LB12. The protective agent formula was optimized using the response surface method (RSM), with the survival rate as the benchmark. The best combination of cryoprotectants was determined to be BZ11: 10 % skimmed milk powder, 3 % sodium glutamate, and 15 % trehalose; LB12: 10 % skim milk powder, 5 % glutamate sodium, and 10 % trehalose; Q-1: 10 % skimmed milk powder, 3 % sodium glutamate, and 10 % trehalose. The survival rate of BZ11 significantly increased to 92.87 ± 1.25 %. The DVS fermented milk did not differ significantly from the control group regarding cholesterol removal, live cell counts and pH (p > 0.05). All DVS can be stored for at least 2500 d at -20 °C-this DVS starter for fermented milk benefits from its large-scale and automated commercial production.

Bifidobacterium species viability in dairy-based probiotic foods: challenges and innovative approaches for accurate viability determination and monitoring of probiotic functionality

Bifidobacterium species are essential members of a healthy human gut microbiota. Their presence in the gut is associated with numerous health outcomes such as protection against gastrointestinal tract infections, inflammation, and metabolic diseases. Regular intake of Bifidobacterium in foods is a sustainable way of maintaining the health benefits associated with its use as a probiotic. Owing to their global acceptance, fermented dairy products (particularly yogurt) are considered the ideal probiotic carrier foods. As envisioned in the definition of probiotics as "live organisms," the therapeutic functionalities of Bifidobacterium spp. depend on maintaining their viability in the foods up to the point of consumption. However, sustaining Bifidobacterium spp. viability during the manufacture and shelf-life of fermented dairy products remains challenging. Hence, this paper discusses the significance of viability as a prerequisite for Bifidobacterium spp. probiotic functionality. The paper focuses on the stress factors that influence Bifidobacterium spp. viability during the manufacture and shelf life of yogurt as an archetypical fermented dairy product that is widely accepted as a delivery vehicle for probiotics. It further expounds the Bifidobacterium spp. physiological and genetic stress response mechanisms as well as the methods for viability retention in yogurt, such as microencapsulation, use of oxygen scavenging lactic acid bacterial strains, and stress-protective agents. The report also explores the topic of viability determination as a critical factor in probiotic quality assurance, wherein, the limitations of culture-based enumeration methods, the challenges of species and strain resolution in the presence of lactic acid bacterial starter and probiotic species are discussed. Finally, new developments and potential applications of next-generation viability determination methods such as flow cytometry, propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR), next-generation sequencing, and single-cell Raman spectroscopy (SCRS) methods are examined.

Application of soybean isolate protein (SPI) and soy hull polysaccharide (SHP) complex in fermentation products

We investigated the stability of a soy protein isolate (SPI)/soy hull polysaccharide (SHP) composite and its effect on the quality of fermented products. Sonication contributed to a more stable SPI/SHP composite. Increasing SHP concentrations increased the viscoelasticity of the emulsions and decreased turbiscan stability index (TSI) values, indicating that SHP improved the emulsification and stability of the composite emulsions. The fermented products with SHP had an increased ability to bind to water. Hardness, gelling, chewiness, sourness, and astringency increased with polysaccharide addition. Additionally, SHP promoted acid production by lactic acid bacteria during storage. All groups had viscoelastic behavior (G' ˃ G″, tan δ < 1), with viscosity increasing and subsequently decreasing. TSI values were significantly lower in the treated groups than in the control group. The results revealed that SHP improved the sensory quality and storage stability of fermented products.

Investigation of some quality properties of yogurt made from cow and sheep milk fortified with folic acid (B9 ), biotin (B7 ), and vitamin D3

BACKGROUND

The aim of this study was to investigate the effects on some physicochemical properties and starter cultures of yogurts enriched with vitamins at different concentrations during storage. For this purpose, yogurt was produced by adding the vitamins folic acid (B9 ), biotin (B7 ), and vitamin D3 in different concentrations to sheep and cow milk and stored at 4 °C. Physicochemical analyses and microbiological analyses were performed for each group of yogurt on days 0, 7, 14, and 21.

RESULTS

There was no significant difference (P > 0.05) between the groups in pH and titration acidity (%) during storage. It was determined that in the yogurts produced from sheep milk, the groups enriched with vitamins had a higher number of L. bulgaricus than the control group on the 7th day of storage. Moreover, the groups containing vitamin D3 exhibited a higher Lactobacillus bulgaricus count on the 21st day of storage. The highest L. bulgaricus counts on the 7th day in yogurts produced from cow's milk were observed in groups containing 0.5 mL of vitamin B9 and B7 . No mold or yeast growth was observed during storage in any of the yogurt groups made from cow and sheep milk.

CONCLUSION

In conclusion, it was determined that the enrichment of yogurt with vitamins B7 , B9 , and D3 did not adversely affect the quality of the yogurt; rather, it improved. We recommend that yogurt enriched with micronutrients be studied economically, and mass production should be initiated by yogurt companies as soon as possible. © 2023 Society of Chemical Industry.

The effects of Trametes versicolor fermented Rosa roxburghii tratt and coix seed quild on the nutrition, sensory characteristics and physical and chemical parameters of yogurt

Trametes versicolor can produce aromatic flavor in growth and development, widely used in food fermentation. This study used a One-Factor-at-a-Time (OFAT) test and response surface analysis to study the optimum fermentation parameters of Rosa roxburghii tratt and coix seed yogurt by Trametes versicolor. The best fermentation process is as follows: skim milk powder 17 %, sucrose content 4 %, Rosa roxburghii tratt and coix seed liquid 36 %, fermentation temperature 39 °C, inoculum 2 %, strain ratio 2:1:1(LB12: BLH1: Q-1), fermentation time 9.5 h. Under this fermentation process, the sensory score was 82.11, the contents of vitamin C, GABA, and total live bacteria in this yogurt were 13.89, 2.58, and 1.02 times higher than in common yogurt. Correlation analyses showed a significant contribution of the leavening agent to the GABA content of yogurt. This study provides a foundation for producing Rosa roxburghii tratt and coix seed yogurt with high sensory and nutritional value.

Effects of ultrasonic processing on the quality properties of fortified yogurt

This study evaluated the effect of ultrasonic processing on functional yogurts fortified with banana-resistant starch (BRS) and green papaya powder (GPP). Ultrasonication technology (80% amplitude, 8 min at 20 kHz frequency) was utilized as an alternative to conventional thermal treatment (85 °C, 30 min) to improve functional yogurts' physical and textural properties. A total of 6 set-type yogurt groups were prepared by ultrasonication (UT) and conventional treatment (CT). Based on the textural studies and correlation (Pearson's) plots, fortified and UT samples were more stiff, firm, sticky, adhesive, and viscous (least elastic) compared to the CT samples. All of the tested yogurts maintained a remarkable number of viable colony counts (≥7.23 log CFU/mL) during the storage. Ultrasonication significantly (p < 0.05) changed the L, a*, and b* color values. The ultrasonic processing reduced whey syneresis and improved the water-holding capacity in fresh and stored yogurts. Further, it retained the fatty acid profile of fortified yogurts. However, ultrasonication negatively affected, i.e., reduced the total polyphenol content and antioxidant activity of yogurts as compared to the conventionally (thermal) treated counterparts. Overall, ultrasound technology can be a potential alternative to thermal treatment for the improved quality and safety of fortified yogurts.

Physicochemical, antioxidant and microbial properties of sweetened yoghurt produced from partial substitution of sugar with soursop puree

This study was targeted towards evaluating the outcome of partially substituting sugar with soursop puree at different proportions, varying pasteurization temperatures, storage durations and with the application of sodium benzoate and potassium sorbate as chemical preservatives on physiochemical, antioxidant and microbial qualities of yoghurt. There was a strong correlation (R2 = 0.7, Adjusted R2 = 0.65) between the syneresis and the water-holding capacity of the yoghurt as the substitution increased. At 50% soursop puree substitution in the yoghurt production, DPPH radical scavenging activity, total phenolic content, vitamin C, carbohydrate, protein, and ash contents increased to 34.40%, 1.25 mg GAE/L, 58.50 mg/100 g, 29.26, 4.02 and 0.69%, respectively. Storage duration does not have a significant influence on the proximate composition of the yoghurt samples. However, the vitamin C content of the yoghurt decreased when the pasteurization temperature was more than 80 °C. The growth of lactic acid bacteria ranged between 2.9 × 105 and 2.16 × 106 CFU/ml. The use of sodium benzoate inhibited yeast growth more than potassium sorbate while soursop substitution inhibited the growth of mould from 1.0 × 106 CFU/ml to 3.05 × 105 CFU/ml than the preservatives. Coliform was absent in all the yoghurt samples with or without preservatives. This information would be valuable in yoghurt development and quality control.

Graphical Abstract

Potentiality of Moringa oleifera as a Nutritive Ingredient in Different Food Matrices

Given the growing interest of today's society in improving the nutritional profile of the food it consumes, industrial food reformulation is booming. In this sense, due to its high yield, good adaptation to climate change and high nutritional potential, Moringa oleifera may be an alternative means of fortifying products, in order to improve different food matrices. The different parts of this plant (leaves, seeds, flowers, pods, roots…) can be marketed for their nutritional and medicinal attributes. In this analysis, various scientific studies have been compiled that evaluate the potential of Moringa oleifera in terms of its incorporation into food matrices and its influence on the final sensory characteristics. In general, the incorporation of different parts of moringa into products, such as bread, pastries, snacks and beverages, increases the nutritional profile of the product (proteins, essential amino acids, minerals and fiber), the dried leaf powder representing an alternative to milk and eggs and helping vegans/vegetarians to consume the same protein content. In the case of dairy and meat products, the goal is to improve the antioxidant and antimicrobial capacity. In every food product, adding high concentrations of moringa leads to greenish colorations, herbal flavors and changes in the mechanical properties (texture, hardness, chewiness, volume and sponginess), negatively impacting the acceptance of the final product. This bibliographic review highlights the need to continue researching the technological properties with the dual aim of incorporating different parts of moringa into food matrices and increasing consumer familiarity with this product.

Effect of set-type yoghurt supplemented with the novel probiotic Lantiplantibacillus plantarum 200655 on physicochemical properties and the modulation of oxidative stress-induced damage

The present study developed a functional yoghurt supplemented with Lantiplantibacillus plantarum 200655 and evaluated its physicochemical properties and antioxidant activities. Yoghurt samples were prepared using commercial starter cultures and probiotics and grouped as follows: control sample without probiotics (C), GG (supplemented with Lacticaseibacillus rhamnosus GG), R (supplemented with L. plantarum KCTC 3108), and S (supplemented with L. plantarum 200655). The GG, R, and S samples had shorter fermentation time compared with the C sample. Lactic acid bacteria count, pH, and titratable acidity were similar in all samples during refrigerated storage. However, the GG, R, and S samples showed increased viscosity and water holding capacity (WHC), and decreased syneresis. The S sample had no adverse effect on organoleptic properties. Furthermore, the S sample had the highest antioxidant activity and significantly inhibited LPS-induced oxidative stress in intestinal cells. These findings suggest the potential use of L. plantarum 200655 in dairy products with therapeutic benefits.

Bioactive Compounds Extracted from Saudi Dates Using Green Methods and Utilization of These Extracts in Functional Yogurt

The bioactive compounds of four Saudi date flesh extracts (Ambara (AF), Majdool (MF), Sagai (SF), and Sukkari (SKF)) prepared using different extraction methods-namely, supercritical fluid extraction (SFE), subcritical CO₂ extraction (SCE), and Soxhlet extraction (SXE)-were evaluated. A total of 19 bioactive compounds were detected in extracts prepared using SFE and SCE methods, whereas less than 12 compounds were detected in extracts obtained using the SXE method. Both the date variety and extraction method affected the phenolic profile of date flesh extract (p ≤ 0.05). The apparent viscosity, surface color, and bioactive properties of yogurt were affected by both date flesh extracts and storage duration in varied magnitudes (p ≤ 0.05). The incorporation of date flesh extracts into yogurt formulations increased the total phenolic content (TPC), DPPH antiradical activity, viscosity, and redness (a*) and decreased the lightness (L*) and yellowness (b*) of the developed product (p ≤ 0.05). The elongation of storage time progressively (p ≤ 0.05) reduced the pH, TPC, DPPH antiradical activity, bacterial counts, and L* and b* values and increased the acidity, syneresis, viscosity, and a* values with few exceptions. Date flesh extracts can improve the health quality of yogurt without major influence on the sensory attributes while stored at 4 °C.

Biologically Active Supplements Affecting Producer Microorganisms in Food Biotechnology: A Review

Microorganisms, fermentation processes, and the resultant metabolic products are a key driving force in biotechnology and, in particular, in food biotechnology. The quantity and/or quality of final manufactured food products are directly related to the efficiency of the metabolic processes of producer microorganisms. Food BioTech companies are naturally interested in increasing the productivity of their biotechnological production lines. This could be achieved via either indirect or direct influence on the fundamental mechanisms governing biological processes occurring in microbial cells. This review considers an approach to improve the efficiency of producer microorganisms through the use of several types of substances or complexes affecting the metabolic processes of microbial producers that are of interest for food biotechnology, particularly fermented milk products. A classification of these supplements will be given, depending on their chemical nature (poly- and oligosaccharides; poly- and oligopeptides, individual amino acids; miscellaneous substances, including vitamins and other organic compounds, minerals, and multicomponent supplements), and the approved results of their application will be comprehensively surveyed.

Enhancing yogurt products’ ingredients: preservation strategies, processing conditions, analytical detection methods, and therapeutic delivery—an overview

As a dairy product, yogurt delivers nourishing milk components through the beneficial microbial fermentation process, improved by bioavailability and bioaccessibility–an exclusive combined food asset. In recent decades, there has been considerable attention to yogurt product development particularly in areas like influence by antioxidant-rich fruits, different factors affecting its probiotic viability, and the functionality of inulin and probiotics. Essentially, many published reviews frequently focus on the functionalities associated with yogurt products, however, those articulating yogurt ingredients specific to associated preservation strategies, processing conditions, and analytical detection techniques are very few, to the best of our knowledge. The knowledge and understanding of preservation strategies that enhance the ingredients in yogurt products, and their function as modern drug delivery systems are essential, given the opportunities it can provide for future research. Therefore, this overview discussed how yogurt product ingredients have been enhanced, from preservation strategies, processing conditions, analytical detection methods, and therapeutic delivery standpoints. The survey methodology involved major stages, from the brainstorming of research questions, search strategy, effective utilization of databases, inclusion and exclusion criteria, etc. The innovative successes of yogurts would be enhanced via the physicochemical, nutritional and therapeutic aspects of the ingredients/products. Besides processing conditions to influence the yogurt constituents, overall acceptability, quality, and shelf-life, the analytical assays would help detect the hidden product constituents, toxins, and other storage-related changes. The therapeutic role of yogurt-a modern drug delivery system, would be demonstrated via the supplementation (of yogurt) either alone or with bioactive ingredients. The future of yogurt requires the collective action of stakeholders to formulate unique variants with different natural blends, where synthetic ingredients become completely replaced by the plant’s derivatives, which enhance the acidification rate and extend shelf life.

Effects of microencapsulation in dairy matrix on the quality characteristics and bioavailability of docosahexaenoic acid astaxanthin

BACKGROUND

Compared with free astaxanthin (Asta), docosahexaenoic acid astaxanthin monoester (Asta-C22:6) has higher stability and bioavailability. However, Asta-E is still unable to be used in the water system. Hence it is necessary to build a water-soluble delivery system. In this study, Asta-C22:6 microemulsion and microcapsule using whey protein isolate (WPI) and hydroxypropyl-β-cyclodextrin (HPβ-CD) as composite wall material were prepared. They were added to three dairy products (milk powder, yogurt and flavored dairy product). A dairy product rich in Asta-C22:6 with high bioavailability was designed by measuring quality characteristics, sensory evaluation and in vivo experiments.

RESULTS

Compared with spray drying, the freeze-drying microcapsule had a higher encapsulation efficiency (72.5%), water content (4%) and better solubility, and Asta-C22:6 microcapsule (1 g L^-1 ) yogurt had the best quality. The bioavailability of Asta-C22:6 microcapsule yogurt was further evaluated. After a single oral dose in mice, the bioavailability of Asta-C22:6 microcapsule in yogurt was significantly increased (C_max  = 0.31 μg mL^-1 , AUC_0-T  = 3.20 h μg mL^-1 ).

CONCLUSION

We successfully prepared Asta-C22:6 microcapsule yogurt, which improved the stability and bioavailability of Asta. The present research is meaningful for delivering unstable bioactive small molecules based on WPI and HPβ-CD. It provides an experimental basis for the application of Asta-C22:6 and the development of functional dairy products. © 2022 Society of Chemical Industry.

The Improvement of Sensory and Bioactive Properties of Yogurt with the Introduction of Tartary Buckwheat

The incorporation of cereals in yogurt has recently gained increasing consumer approval, for its high nutritional value and health benefits, all over the world. Following this emerging trend, Tartary buckwheat (TB) was supplemented into yogurt as a natural functional ingredient in order to develop a yogurt with enhanced product characteristics and consumer acceptability. The impact of TB addition on physicochemical properties (pH, acidity, apparent viscosity, etc.) and the viability of lactic acid bacteria in yogurt was investigated. It is found that the TB introduction can reduce the pH, increase the acidity and apparent viscosity, and also greatly boost the bioactivities of yogurt. Response surface analysis demonstrated that yogurt with 8 g of TB, 10 g of sugar, and a fermentation duration of 5 h had the highest overall acceptability, and these cultural conditions were chosen as the best. Furthermore, the TB-added yogurt had not only a better sensory and aroma profile, but also good prospective health advantages when compared to regular yogurt. Our research shows that adding TB to yogurt has a significant positive impact on both overall quality and sensory characteristics, making a compelling case for using TB yogurt and developing new fermented dairy products.

Functional dairy products as a source of bioactive peptides and probiotics: current trends and future prospectives

Milk is an incredibly healthy food world-wide. However, the 'lactase deficient' individuals cannot digest milk's carbohydrate lactose. A large part of the world population is depriving of highly beneficial milk proteins like casein, lactoalbumin, lactoglobulin, etc. due to lactose intolerance. Production of functional foods and bioactive peptides from milk with natural antioxidants and the addition of probiotics could be the best alternative to extend the use of milk functionalities. Among different probiotics, the lactic acid bacteria (LAB) like Lactobacillus delbrueckii sub sp. bulgaricus, Streptococcus thermophilus and some species of Bifidobacteria and their metabolites (paraprobiotics and postbiotics) have been given more preference to add in milk-derived functional foods. These species are generally considered as heat-tolerant, highly proteolytic, and peptidolytic towards milk proteins and they liberate smaller molecules of bioactive peptides during fermentation and other processes that stimulate the enzyme lactase to help people in digestion of milk carbohydrate lactose. Moreover, the incorporation of natural antioxidants in yoghurt and other dairy products prevents the rancidity of milk fat. The level of bioactive peptides produced in milk-derived functional foods can be determined by capillary zone electrophoresis, mass spectrometry, fractionation, and other modern assessment techniques. Commercial production of functional probiotic products with bioactive peptides could significantly contribute to reduce milk spoilage, enhance health benefits as well as the growth of the agro-processing industry.

The Effects of Adding a Gel-Alike Curcuma longa L. Suspension as Color Agent on Some Quality and Sensory Properties of Yogurt

Color is an important characteristic of food products. This characteristic is related to consumer acceptability. To use the entire rhizome of Curcuma longa (CL) as a food colorant, a novel gel alike stable suspension (CLS) was previously developed using cellulose nanofibers (CNFs). Therefore, the present study was conducted to evaluate the CLS as a color additive on a stirred yogurt. Three concentrations of CLS were studied (0.1, 0.125, and 0.15 wt. %) and compared to yogurt without CLS. The obtained yogurts were characterized through the determination of pH, titratable acidity, syneresis, color and curcumin content after 1, 7, 14, and 21 days of storage. Additionally, rheological and sensory measurements were performed on the samples after one day of storage. Results show that the addition of CLS does not affect the pH and titratable acidity of the samples, but all the yogurts showed an increase in their syneresis during the storage time, showing a breakdown of the gel structure. Furthermore, the CLS suspension has the ability to impart a yellow color to yogurts, a characteristic that was stable during storage. Finally, the addition of 1 wt. % or 1.25 wt. % of CLS allows the development of a yogurt with adequate sensory perception.

Effect of Supercritical Extract from Black Poplar and Basket Willow on the Quality of Natural and Probiotic Drinkable Yogurt

Yogurt is a fermented milk drink produced by Streptococcus thermophilus, Lactobacillus delbrüeckii ssp. bulgaricus, or Lactobacillus rhamnosus, which can be enriched with polyphenolic compounds to enhance its antioxidant properties. Supercritical (scCO2/H2O) extracts obtained from the mixture of bark and wood of black poplar (Populus nigra) and basket willow (Salix viminalis) are the source of bioactive compounds. The aim of the study was to assess the effect of supercritical extracts from the P. nigra and S. viminalis on the fermentation, quality, and bioactive properties of drinkable natural and probiotic yogurts. The incorporation of scCO2/H2O extracts at a dose of 0.01% (w/v) into milk for the production of natural and probiotic yogurts increases their functional properties by enhancing the antioxidant activity without causing negative effects on the physicochemical and organoleptic properties of products. The antioxidant activity of yogurt with scCO2/H2O extract from P. nigra and S. viminalis was higher than control yogurts by 1.3-13.2% and 4.4-37.5%, respectively. The addition of a supercritical S. viminalis extract reduced the time of natural and probiotic yogurt fermentation. Natural and probiotic yogurt with scCO2/H2O extracts added was characterised by a bacterial population size of over 7 log cfu/g, and the microflora was active throughout the cold storage period. FTIR analysis confirmed the presence of scCO2/H2O extracts from P. nigra or S. viminalis in both types of yogurt. A secondary structure analysis confirmed interactions between compounds of scCO2/H2O extract from P. nigra and S. viminalis extract with milk proteins. These interactions affect the compounds' structural and functional properties by changing, e.g., their digestibility and antioxidant properties.

Yogurt Fortification by the Addition of Microencapsulated Stripped Weakfish (Cynoscion guatucupa) Protein Hydrolysate

The aim of the present work was to fortify yogurt by adding a stripped weakfish (Cynoscion guatucupa) protein hydrolysate obtained with the enzyme Protamex and microencapsulated by spray drying, using maltodextrin (MD) as wall material. The effects on the physicochemical properties, syneresis, texture, viscoelasticity, antioxidant and ACE inhibitory activities of yogurt after 1 and 7 days of storage were evaluated. In addition, microbiological and sensory analyses were performed. Four yogurt formulations were prepared: control yogurt (without additives, YC), yogurt with MD (2.1%, YMD), with the free hydrolysate (1.4%, YH) and the microencapsulated hydrolysate (3.5%, YHEn). Yogurts to which free and microencapsulated hydrolysates were added presented similar characteristics, such as a slight reduction in pH and increased acidity, with a greater tendency to present a yellow color compared with the control yogurt. Moreover, they showed less syneresis, the lowest value being that of YHEn, which also showed a slight increase in cohesiveness and greater rheological stability after one week of storage. All yogurts showed high counts of the microorganisms used as starters. The hydrolysate presence in both forms resulted in yogurts with antioxidant activity and potent ACE-inhibitory activity, which were maintained after 7 days of storage. The incorporation of the hydrolysate in the microencapsulated form presented greater advantages than the direct incorporation, since encapsulation masked the fishy flavor of the hydrolysate, resulting in stable and sensorily acceptable yogurts with antioxidant and ACE inhibitory activities.

Comparison of the Probiotic Potential between Lactiplantibacillus plantarum Isolated from Kimchi and Standard Probiotic Strains Isolated from Different Sources

In the present study, the properties of the Lactiplantibacillus (Lpb.) plantarum WiKim0112 isolated from kimchi were evaluated by comparing its probiotic properties to those of Lpb. plantarum WCFS1 and KACC 11451 isolated from different sources. In both pH 2 and 3, media containing pepsin, Wikim0112, and WCFS1 showed higher cell viability than KACC11451. Viability of all Lpb. plantarum strains in a medium containing pancreatin and bile salt oxgall was significantly decreased compared to the control. WCFS1 showed the highest thermotolerance, followed by Wikim0112 and KACC11451. Wikim0112 showed a similar level of antibacterial activity to WCFS1 and exhibited an overall higher antibacterial activity than KACC11451 against six pathogens. All Lpb. plantatum strains showed high antioxidant activities in SOD, DPPH, and ABTS assays, especially Wikim0112 and WCFS1 exhibited a higher antioxidant activity than KACC11451. All Lpb. plantarum strains showed approximately 60–62% adhesion rates to Caco-2 cells. Moreover, in LPS-stimulated Caco-2 cells, all Lpb. plantarum strains significantly decreased the mRNA expression of pro-inflammatory cytokines (i.e., IL-1β, IL-6, and TNF-α); Wikim0112 significantly increased the mRNA expression of IL-4 and IFN-γ. Wikim0112 was resistant to streptomycin and vancomycin, whereas WCFS1 and KACC11451 were resistant to four (clindamycin, ciprofloxacin, tetracycline, and vancomycin) and three (ciprofloxacin, tetracycline, and vancomycin) antibiotics, respectively. These results, taken together, indicated that compared to Lpb. plantarum strains isolated from different sources, Wikim0112 showed desirable probiotic properties, suggesting its potential applications in the food and pharmaceutical industries.

Effect of Two Combined Functional Additives on Yoghurt Properties

The aim of the research was the analysis of yoghurts enriched with blue honeysuckle berries dry polyphenolic extract and new preparation of resistant starch. The additives were introduced individually at concentration 0.1% (w/v) and in mixture at final concentration of 0.1 and 0.2% of both components. Yogurt microflora, pH, and its physicochemical and antioxidant properties were examined over 14 days of storage under refrigerated conditions. Studies showed that both substances can be successfully used in yoghurt production. Yoghurt microflora es. S. thermophilus and Lb. delbrueckii subsp. bulgaricus counts appeared to be higher in samples supplemented with these additives comparing to control yoghurt by 3-8%. More stimulating effect on their growth, especially on S. thermophilus, revealed resistant starch. Addition of this polysaccharide improved also the rheological properties of yogurts, which showed higher viscosity than samples produced without it. Addition of honeysuckle berries preparation significantly influenced the yogurts' color, giving them deep purple color, and their antioxidant potential. During storage, contents of anthocyanin and iridoid compounds were decreasing, but antioxidant activity in the products remained stable.

Co-fermentation process strongly affect the nutritional, texture, syneresis, fatty acids and aromatic compounds of dromedary UF-yogurt

This work intended to compare dromedary yogurt's characteristics obtained by a co-fermentation process with plant (carob powder) or autochthonous bacteria (Enterococcus faecium and Streptococcus macedonicus). For this reason, the ultrafiltration process (UF) is applied to increase the rate of total solids in dromedary milk within the margin needed to prepare a yogurt. Carob powder or autochthonous bacteria were incorporated at the level of 2% in UF milk. Then mixtures were fermented with the strains Lactobacillus bulgaricus and Streptococcus thermophiles, and the obtained products are named CFC (yogurt with carob), CFS (yogurt with autochthonous strains) and control (yogurt with only L. bulgaricus and S. thermophilus) respectively. All along of 3 weeks at cold, CFC and CFS maintained Streptococcus at appropriate levels (>8 log CFU/g). Moreover, CFC showed the lowest syneresis, highest cohesiveness and springiness values, and oleic acid (C18:1n9; 26.315%). However, CFS yogurt resulted in higher volatile compound formation than CFC and control, where isobornyl propionate was the major one.