Effect of reduced fat content on the physicochemical and microbiological properties of buffalo milk yoghurt

Investigation of the effects of corn flour, Spirulina powder, and buffalo yogurt on the quality characteristics of gluten-free muffins

This study aimed to investigate the properties of buckwheat flour-based gluten-free muffins formulated by using corn flour (CF), Spirulina powder (SP), and buffalo yogurt (BY) levels as the factors in the Box-Behnken experimental design. The color values, total soluble polyphenol content (TPC), radical scavenging activity (RSA), specific volume, moisture content, and baking loss results were evaluated as the response variables in the design. The buckwheat flour in the control sample was substituted with CF and SP. Cow yogurt was used in the control muffin instead of milk and was substituted with BY at different levels in other samples. Among the response variables, TPC and RSA values were selected for the optimization studies. Decreasing the CF and SP levels in the formulations resulted in observing higher TPC and RSA values. Three optimal formulations were obtained by response surface methodology. Both cow and buffalo yogurt did not change the properties of the muffins adversely compared to milk. Increasing the SP content made the muffins firmer and caused a decrease in the L*, a*, b*, and browning index values of the muffins. However, sensory scores of SP-containing muffins were also satisfactory.

Limosilactobacillus fermentum ING8, a Potential Multifunctional Non-Starter Strain with Relevant Technological Properties and Antimicrobial Activity

Lactic acid bacteria (LAB) have gained particular attention among different exopolysaccharide-producing microorganisms due to their safety status and effects on human health and food production. Exopolysaccharide-producing LAB play a crucial role in different ways, such as improving texture, mouthfeel, controlling viscosity, and for low-calorie food production. In this study, we isolated a multifunctional strain with good exopolysaccharide production properties. Limosilactobacillus fermentum ING8 was isolated from an Indian traditional fermented milk (Dahi) and evaluated for its safety, enzymatic activity, NaCl resistance and temperature tolerance, milk coagulation, and storage stability. Finally, the complete genome of this strain was sequenced and subjected to safety in silico evaluation and genomic analysis. The results revealed that L. fermentum ING8 possesses relevant technological properties, such as exopolysaccharide production, antimicrobial activity, and galactose utilization. Besides, this strain showed very high stability to storage conditions at refrigeration temperature. In addition, the genomic analysis did not evidence any possible deleterious elements, such as acquired antibiotic resistance genes, virulence genes, or hemolysis-related genes. However, all structural genes related to the galactose operon and EPS production were detected. Therefore, L. fermentum ING8 can be considered a promising multifunctional bacterium to be proposed as non-starter in different types of dairy productions.

Microstructural and rheological behavior of buffalo milk chocolates

The development of products with buffalo milk has increased due to its peculiar characteristics, such as taste and high content of total solids, which has attracted consumers and the food industry.In this context, the objective was to develop and evaluate the microstructural properties of chocolates with different concentrations of buffalo milk powder (0%, 5%, 10%, 15% and 20%) through polymorphism, microscopy and rheological studies. For the polymorphism, the X-ray diffraction technique (XRD) was performed, while the crystal morphology was observed by scanning electron microscopy (SEM). The addition of levels of more than 10% buffalo milk caused notable changes in XRD diffractograms, demonstrating the appearance of different polymorphic forms. Microscopy analysis revealed changes in the structure of the matrix with an increase in the concentration of buffalo milk, presenting more continuous surfaces, associated with milk proteins, which have emulsifying capacity. The Herschel-Bulkley model adequately described the flow behavior of the formulations. There was an increase in all rheological properties (yield stress, viscosity, thixotropy and loss tangent (tang δ)) in chocolates with higher concentrations of milk. For that, the composition of the milk influences the degree of structuring of the chocolate. Considering this technological information, it is important to highlight that the production of buffalo milk chocolates shows potential for technological innovation.

Buffalo Milk as a Source of Probiotic Functional Products

In the past two decades, consumption of food has been accruing due to its health claims which include gastrointestinal health, improved immunity, and well-being. Currently, the dairy industry is the sector where probiotics are most widely used, especially in fermented milk, cheese, yoghurt, butter, and dairy beverages. Although, it is still necessary to face many challenges regarding their stability and functionality in food. Considering the increasing demand for healthy products, it is necessary to develop strategies that aim to increase the consumption of functional foods in order to meet probiotic usefulness criteria and the consumer market. This review aimed to promote the utilization of buffalo milk considering its probiotic effects as a functional food and natural remedy to various ailments, emphasizing the potential of innovation and the importance of milk-based products as health promoters. The intake of probiotics plays an important role in modulating the health of the host, as a result of a balanced intestinal microbiota, reducing the risk of development of various diseases such as cancer, colitis, lactose intolerance, heart diseases, and obesity, among other disorders. However, further studies should be carried out to deepen the knowledge on the relationship between raw buffalo milk, its dairy products microbiota and consumer’s health beneficial effects, as well as to implement a strategy to increase the variety and availability of its products as a functional food in the market.

Effects of Homogenization and Heat Treatment of Milk with Different Fat Content on Physical Properties of Ayran

In this research, the effects of different homogenization pressure levels (15, 40, 15/3 and 40/8 MPa) and heat treatments (95°C for 90 s and 300 s) of milk containing 1.5 and 2.5% of fat on some physical properties of ayran were investigated during storage at 4°C for 30 days. The individual effects of fat content of milk, homogenization, heat treatment, and storage period on the syneresis, apparent viscosity, consistency constant and thixotropy values of the ayran samples were statistically significant. Based on the results of rheological analysis, the power law model was more appropriate for all ayran samples.

Effect of yam (Dioscorea spp.) starch on the physicochemical, rheological, and sensory properties of yogurt

This study investigated the effect of the addition of starch from “hawthorn” yam (Dioscorea rotundata) and “creole” yam (Dioscorea alata) at different concentrations (0.1%, 0.3%, and 0.5% w/w) on the physicochemical and sensory properties of stirred-type yogurt. Pectin (0.3% w/w) was used as a reference stabilizer. Yogurt with yam starch presented 13.38% less syneresis than yogurts with pectin. At the sensory level, the most accepted treatment was yogurt with “creole” yam starch at 0.1% w/w. During 21 days of storage, yogurt with yam starch (“creole” and “hawthorn”) at 0.1% w/w showed a decrease in syneresis between 7% and 8%, while in those with pectin, syneresis remained practically constant in this period. Yogurt with yam starch was characterized as a pseudoplastic fluid, with a lactic acid bacterial count according to NTC 805. Yam starch can be used as stabilizer because it improves the physicochemical, sensory, and rheological characteristics of stirred-type yogurt. Especially the “creole” yam starch (0.1% w/w), which presents the best preference by consumers.

Effect of Plantago ovata Forsk seed mucilage on survivability of Lactobacillus acidophilus, physicochemical and sensory attributes of produced low-fat set yoghurt

Nowadays, consumers' attention to the functional foods has increased significantly. In this study, the effect of different concentration (0.5, 1, and 2%) of P.ovata Forsk seed mucilage (PFM) on survivability of L.acidophilus, physicochemical, and sensory attributes of produced low-fat yoghurt were investigated in 0, 7, 14, and 21 days of storage period. Results showed that at the beginning of the storage period, the number of L.acidophilus in yoghurt samples containing PFM was significantly higher than control sample. The highest number of L.Acidophilus was observed in yoghurt sample contain 2% PFM (6.68 log CFU/g) on the first day of storage period. The lowest decrease of L.Acidophilus (0.2 log CFU/g) was observed in the sample contain 2% PFM. Treatments containing PFM had lower pH and higher acidity than the control sample. Addition of PFM to the yoghurt samples increased water holding capacity (WHC) during storage period significantly while syneresis decreased. The highest WHC (89%) and the lowest syneresis (6%) were observed in yoghurt sample containing 2% PFM. Sensory evaluation results showed that the treatments containing PFM were not significantly different in taste, but the probiotic yogurt containing 1% PFM had the highest acceptability in terms of total appearance and texture. Evaluation of L, a, and b values indicated that yoghurt sample containing 2% PFM was significantly lower in L and b values and higher in a value than the control sample. Therefore, using P.ovata Forsk seed mucilage in yoghurt sample formulation improved the physicochemical attributes and probiotic survivability of produced yoghurt sample.

Effects of fat content on the textural and in vivo buccal breakdown properties of soy yogurt

This study aimed to evaluate the effects of fat content on the textural and in vivo buccal breakdown properties of soy yogurt (SY) at different pH (5.4, 5.0, and 4.6). The microbial analysis, textural and rheological properties, and interfacial protein composition of all the samples were monitored. Microbial results suggested that the increased fat content in SY-5.0 and SY-4.6 resulted in significantly high viable cell counts of lactic acid bacteria (LAB). Textural studies demonstrated that the presence of a low fat content (1-3%) significantly reduced the hardness, springiness, and gumminess of the sample, but this effect was negligible with the addition of fat content (4-5%). The apparent viscosity and thixotropy of the SY-4.6 sample increased as the fat content increased. in vivo buccal digestion showed that a high fat content (2-4%) reduced the number of chews and chewing durations, which might be correlated with high oil droplet release (%) after mastication.

Effect of milk types on the attributes of a glutinous rice wine-fermented yogurt-like product

This study was conducted to analyze the effect of milk types on the attributes of the glutinous rice wine-fermented yogurt-like product named Kouwan Lao (KWL). Four types of raw milks were used in this study, including high temperature, long time (HTLT: H milk), HTLT milk supplemented with 3% skim milk powder (S milk), pasteurized milk (P milk), and ultra-high temperature milk (U milk). Microbiological compositions of the fermented glutinous rice and KWL at different stages were analyzed using PCR-denaturing gradient gel electrophoresis and gene sequencing based on 16S rRNA and 26S rRNA. The physicochemical properties of KWL samples were determined, and textural properties of those were analyzed using a texture analyzer (Jiawei Innovation and Technology Co. Ltd., Zhejiang Province, China). The microstructure of KWL samples was observed using scanning electron microscopy. The results showed that the milk types had significant influences on the bacterial composition of KWL. In the curdling process, the predominant bacteria of H, S, P, and U KWL samples were Lactobacillus brevis, Janthinobacterium sp., Lactobacillus casei, and Streptococcus agalactiae, respectively. In the ripening process, the main strains in H KWL were Enterococcus faecium and Pediococcus pentosaceus. Lactobacillus casei and Lactobacillus paracasei were the dominant bacteria of U KWL. Lactobacillus casei was the main strain of P KWL, and no bacteria were detected in S KWL. Saccharomyces cerevisiae was the dominant fungus of KWL, and no significant effect of milk types on fungal composition of KWL was found. The results of physicochemical properties showed that significant differences in protein contents were found in the KWL samples, and P KWL had the highest protein content. The fat content of U KWL was significantly higher than that of samples from the other 3 groups. The U KWL and P KWL showed lower moisture than that of the other 2 KWL samples. In addition, no significant difference in pH value was found in all samples. The results of texture analysis and microstructure showed that compared with other 3 types of KWL samples, the related mass parameters of U KWL were more advantageous and improved significantly with the increase of the heat treatment temperature of raw milk and the addition of skim milk powder. Our findings revealed the effects of milk types on microbial composition, physicochemical properties, textural properties, and microstructure of KWL, and provided a basic theory for the optimization and industrial production of KWL.

Comprehensive Evaluation of Microbiological and Physicochemical Properties of Commercial Drinking Yogurts in Korea

Most consumers consider yogurt to be a healthy food because it contains probiotic microorganisms. Although a plethora of commercially produced yogurts exists, nutritional and functional aspects of the commercial yogurts have not been well characterized. In this study, the microbiological and physicochemical properties of popular drinking yogurts in Korea were extensively characterized. The viability of lactic acid bacteria, including lactobacilli and bifidobacteria, varied between yogurt samples. These lactobacilli and bifidobacteria showed effective antimicrobial activities against foodborne pathogenic bacteria. Unlike the titratable acidity and pH, the soluble solids content varied between yogurt samples. All the yogurt samples contained high levels of potassium (average 143.53 mg/100 g) and calcium (average 133.92 mg/100 g), as well as phosphorus and sodium. Lactose, fructose, and glucose were the major sugar components in most yogurt samples, whereas the levels of sucrose and maltose were relatively low. Among several organic acids analyzed in the yogurt samples, lactic acid (average 767.67 mg/100 g) and citric acid (average 170.91 mg/100 g) were the most predominant. Taken together, this study provides preliminary information about the nutritional and functional characteristics of commercially available drinking yogurts.

Texture and sensory characterization of functional yogurt supplemented with flaxseed during cold storage

In this study, flaxseed was used as a functional ingredient in yogurt formulations. The goal of this study was to produce prebiotic yogurt supplemented with flaxseed and investigation of its texture and sensory properties. Yogurt samples containing 0%-4% flaxseed was produced and stored at refrigerator (4-5°C) for 28 days. Textural properties were determined by texture analysis, and sensory characteristics were assessed by 26 trained panelists. Addition of flaxseed to yogurt samples increased the hardness, gumminess, chewiness, cohesiveness, and springiness values in produced yogurt samples. However, adhesiveness level was reduced in a sample enriched with flaxseed. By increasing flaxseed concentration, the color of samples was significantly different than the control sample; L* value was diminished and a* and b* value increased. Sensory scores including taste and mouthfeel, appearance, and overall acceptance showed reduction trend in samples containing a high level of flaxseed. In general, results showed that the addition of 2.63% flaxseed into yogurt samples lead to produce functional food with satisfactory texture, sensory characteristics that sustained these properties until 17.17 days after cold storage.

Effect of short chain inulin on the rheological and sensory characteristics of reduced fat set coconut milk yoghurt

The effect of short-chain inulin on the rheological and sensory properties of reduced fat set coconut milk yoghurt was studied with whole fat coconut milk yoghurt as reference. The concentration of short-chain inulin was varied at 0, 5, 10, 15, and 20% w/v respectively. All the yoghurt samples displayed higher elastic modulus G' than viscous modulus G". However, 15% inulin yoghurt had the highest value for G' & G". The 15 and 20% inulin yoghurts displayed high yield stress (1036.7 ± 2.39 & 368.23 ± 0.30 Pa). Addition threshold of 15% was established, beyond this level there was a significant decrease in the yield stress, firmness, cohesiveness and consistency values of the reduced fat yoghurts. Using Pearson correlation analysis, no correlation was observed between firmness and yield stress, Similarly, there was significant correlation between the yield stress and instrumental viscosity r = 0.957; p < 0.01. Furthermore, all yoghurt samples displayed strain thinning behavior except whole fat yoghurt. Carbohydrate was affected by inulin incorporation. Addition of short chain inulin improved sensorial characteristics such as taste, and flavor, but did not display significant difference in color and odor of yoghurt samples. This article is protected by copyright. All rights reserved.

The combined effect of probiotic cultures and incubation final pH on the quality of buffalo milk yogurt during cold storage

The combined effects of starter culture type (SCT) and incubation final pH (IFpH) on the physicochemical and organoleptic properties of buffalo milk yogurt containing 3 g·100 g⁻¹ milk fat were investigated throughout 20 days of storage at 4°C. The postacidification kinetics fitted to zero‐order reaction for all buffalo milk yogurt samples. The reaction rate constants of the buffalo milk yogurt samples containing YC‐X11, ABY‐2, and ABT‐4 cultures were 0.010, 0.007, and 0.004 g·100 g⁻¹·day⁻¹, respectively. Regardless of the IFpH, the absence of Lactobacillus delbrueckii subsp. bulgaricus in the starter culture increased the syneresis. L*, a*, and b* values were not affected by the IFpH and the SCT. ABY‐2 culture increased the amount of organic acids during cold storage in comparison with the YC‐X11, while its effect on the proportions of saturated and unsaturated fatty acids was not significant. The results of sensory evaluation revealed that a more acceptable buffalo milk yogurt can be manufactured by using probiotic ABY‐2 culture.