Techno-functional properties and enhanced consumer acceptance of whipped fermented milk with Ficus carica L. By-products.

The development of new fermented milks formulations enriched with fruit by-products may widen the existing market offer of products matching consumer demands on novel, and "no artificial added sugars" products. Unmarketable fig fruit, food by-product, could be considered as a potential ingredient to develop a new dairy product. The aim of this study was to study the consumer acceptance of fermented milk enriched with different percentage of pasteurized fig purée (by-products) and their technological properties. It was found that the quantity of fig puree added influenced fermented milks texture and spontaneous syneresis. Formulations containing 40% fig puree showed the highest values of firmness, consistency, cohesiveness, and viscosity index with improvements seen from 20% fig puree addition. Furthermore, the inclusion of fig puree in fermented milks reduced the levels of lactic acid bacteria comparing with control samples, but the microbial load was higher than 106 UFC g-1 LAB (estimated counts in MRS) and 9 UFC g-1 LAC (estimated counts in M17). Polyphenolic content increased with fig puree percentage, enhancing antioxidant activity. Volatile compound analysis identified hexanoic acid, acetoin, and butanoic acid as predominant in enriched fermented milks. It is also worth highlighting that sensory evaluation revealed better ratings for texture and sweetness acceptance in formulations containing 30% and 40% of fig puree, correlating with instrumental data. Overall, the quality parameters were maintained and even improved, leading to high consumer acceptability ratings.

Development and evaluation of fermented milk with Lactobacillus acidophilus added to concentrated cranberry (Vaccinium macrocarpon) juice with the potential to minimize the recurrence of urinary tract infections.

Repeated urinary tract infections affect many people worldwide. A potential strategy to reduce the incidence of these infections is to consume probiotics and cranberry fruit regularly. In this context, this study aims to prepare fermented milk with Lactobacillus acidophilus La-5 added with concentrated cranberry juice in two concentrations (5 and 10 %, corresponding to C1 and C2 samples, respectively) and evaluate different technological aspects of the samples after production and during storage, and comparing with the control sample (C). The juice had pH 1.91, 70.09 % of solids, and total proanthocyanidins and A-type proanthocyanidins (PACs) values of 117.03 mg/100 g and 16.38 mg/100 g, respectively. The higher the juice content added to the product, the higher the acidity (1.4 and 2.6 g of lactic acid in 100 g, corresponding to C1 and C2 on day 1 (D1), respectively), the total proanthocyanidin content (1.96 and 4.01 mg/100 g on D1; and 1.31 and 3.05 mg/100 g on day 28 of storage (D28), corresponding to C1 and C2, respectively) and A-type proanthocyanidin (0.56 and 1.26 mg/100 g in Day 1; and 0.54 and 1.19 mg/100 g in D28, corresponding to C1 and C2, respectively), higher the values of the color parameters (L*a* and C*), and lower pH value, probiotic viability, and sensory acceptance. Furthermore, the rheological parameters demonstrated a stronger protein network due to the addition of cranberry. The new formulations, including samples C1 and C2, are alternatives as functional products, which regular consumption probably has the potential to minimize the recurrence of urinary tract infections.

Novel Insights in the Application of Probiotic Yeast Saccharomyces boulardii in Dairy Products and Health Promotion.

Probiotic organisms are increasingly being incorporated into foods in order to develop products to prevent and reduce many diseases. Saccharomyces boulardii, a probiotic yeast with unique properties, such as viability over a wide pH range, antibiotic resistance, and the ability to reach a steady state, has an advantage over bacterial probiotics. The present review highlights the potential application of S. boulardii in functional fermented dairy products and the genetic engineering of this probiotic microorganism as a therapeutic agent for the treatment of various infectious diseases. It was found that probiotic yeast stimulates the growth of lactic acid bacteria in dairy products, creating favorable conditions and positively affecting the product's sensory characteristics. Moreover, its viability of more than 106 cfu/mL at the end of the yogurt shelf life confirms its probiotic effect. On the other hand, there is a growing interest in the design of probiotic strains to improve their characteristics and fill existing gaps in their spectrum of action such as the inhibition of some bacterial toxins, as well as anti-inflammatory and immunomodulatory effects. The strengthening of immune functions and effective therapies against various diseases by S. boulardii was confirmed. However, considering this yeast species' potential, further research is necessary to accurately determine the functional properties in terms of incorporation into food matrices and from the aspect of health and well-being claims.

Value addition to dietetic frozen yoghurt through use of fruit peel solids.

The study pertains to preparing value added frozen yoghurt through use of orange peel powder (OPP). The quality aspects of medium-fat (6.0% fat) frozen yoghurt prepared using OPP at three levels (1.5, 2.5, 3.5% as T1, T2 and T3 respectively) was studied. Frozen yoghurt was prepared by freezing blend of fermented yoghurt base with ice cream mix (25:75 w/w); other ingredients were sugar, stabilizer-emulsifier and orange crush. Inclusion of OPP in frozen yoghurt impacted the orange flavour favorably and enriched product with ß-carotene and dietary fiber. The control product (TC) was prepared in similar manner, avoiding OPP. As the level of OPP was raised in formulation, there was a marked increase in the protein, carbohydrate, ash and total solids when compared with TC. Presence of OPP markedly affected the acidity, viscosity, overrun and melting resistance of the product; maximum overrun was associated with TC. Product T3 had the maximum acidity and viscosity; T2 had maximum total sensory score. It is recommended to prepare medium-fat frozen yoghurt utilizing 2.5% OPP along with orange crush as flavouring. Such inclusion of peel solids enriched the product with ß-carotene and dietary fiber, contributed to stabilization of product and enhanced the products sensory acceptance.

Comprehensive Analysis of Yoghurt Made with the Addition of Yellow Mealworm Powder (Tenebrio molitor).

The study aimed to be able to incorporate mealworm powder into yoghurts to increase protein content. Tenebrio molitor is gaining popularity as an alternative protein source. In the face of a growing human population and the associated challenges of sustainable nutrition, mealworms offer a promising solution. The mealworm is distinguished by its high protein content and for being rich in essential amino acids, vitamins, and minerals, making it a valuable component of diet. Among others, chemical composition, colour, texture, degree of syneresis, sensory analysis, and microbiological analysis were analysed. As expected, the addition of insect powder increased the protein content from 4.91% (0 TM) to 7.41% (5 TM). It also increased the fat content from 1.67% (0 TM) to 3.88% (5 TM). Furthermore, the addition of mealworm powder resulted in a significant change in the colour of the yoghurt to a darker colour, due to the dark brown colour of the powder. Food with added edible insects is increasingly available but is not always popular due to cultural and psychological barriers. Sensory analysis of yoghurts has shown that the more powder that is added, the less appealing the product becomes and the more bitter the taste.

Use of House Cricket (Acheta domesticus) Powder in Yoghurt Products.

This study aims to implement and increase values regarding the use of cricket powder in food. This is due to the need to increase the range of products enriched with cricket powder in order to increase the market and acceptance of insects in the diet. The work analyzed properties of yoghurt with cricket powder added (chemical composition, acidity, colour, consistency, degree of syneresis, texture and sensory analysis). Research has shown that the greater the addition of cricket powder, the higher the protein, fat and dry matter content and the lower the hardness of the yoghurt. As the content of cricket powder in yoghurt increased, the brightness (L*) and redness (a*) decreased, while the yellowness (b*) of the samples increased. A change in the colour of the yoghurt was observed with the increase in the cricket powder content; the yoghurt had a darker, browner colour. The best overall sensory rating compared to the control variant (6.4) was given to the yoghurt with 1.5% cricket powder added (5.7), while the worst rating was given to the yoghurt with 5% powder added (2 points out of 7).

Investigating the impact of milk protein, inulin, and honey on quality attributes of goat milk yoghurt.

In this present study, a three-factor Box-Behnken, response surface methodology (RSM) design was employed to optimize the skimmed milk powder (SMP)/whey protein concentrate (WPC) ratio (0.25-0.75%w/v) as a source of milk protein, inulin (1-2%w/v), and honey (4-6%w/v) for production of high-quality goat milk yoghurt (GMY). The resulting ANOVA and response surface equations revealed the significant effect (p < 0.05) of these variables on the various attributes such as total solid (%), pH, titratable acidity [(LA) % by weight], syneresis (%), DPPH (% inhibition), viscosity (m.Pa⋅s), whiteness index (WI), and overall acceptability (OA). The coefficient of determination (R2) for all response variables ranged from 0.88 to 0.99. Lack-of-fit tests resulted in non-significant F-values. The optimal conditions were determined as SMP/WPC at 0.36%w/v, inulin at 1.00%w/v, and honey at 6.00%w/v. The optimum values for total solid, pH, titratable acidity, syneresis, DPPH, viscosity, WI, and OA were 22.03, 4.46, 0.77, 6.34, 25.20, 182.30, 76.29 and 8.37, respectively with desirability value of 0.95.

Quality Assessment of Greek-Style Set Yoghurt Fortified with Extracted and Dried Australian Native Fruit, Illawarra Plum.

The Illawarra plum (IP) is native to Australia and has been used as a bush food for centuries. With rich phytochemicals and natural pigments, IP has the potential to be an added ingredient to improve the physicochemical properties of food, including yoghurt. This study prepared dried IP powders through vacuum drying (VD) and freeze drying (FD), produced extracts from these dried powders, and fortified them into Greek-style set yoghurt. The changes in colour, pH, titratable acidity (TA), syneresis, total soluble solids (TS), and phytochemicals were measured throughout a chilled storage period of 28 days. The results showed that FD and FD extract could provide a stable, distinct pink colour to yoghurt. IP powders and their extracts improved TS content and, thus, the consistency of yoghurt. Compared to the control, VD, FD, and FD extract of IP did not significantly affect the level of acidity or syneresis after 28 days of chilled storage. Yoghurt fortified with FD and FD extract had the greatest level of phenolics, anthocyanins, and radical scavenging antioxidant activities. This study revealed that IP powders and their extracts can positively improve the physicochemical properties of Greek-style set yoghurt. FD powder is recommended over its extract to fortify this yoghurt, as it can be cost-effectively prepared by freeze drying and then grinding the fresh fruit into powder. Future studies are needed to evaluate other variables in yoghurt preparation, including the concentration of IP and strains of yoghurt culture. Further, the consumer perception of sensory quality and acceptability of yoghurt fortified with FD IP powder should be investigated.

Consumption of dairy foods to achieve recommended levels for older adults has no deleterious effects on serum lipids.

BACKGROUND AND AIMS: Correction of calcium and protein undernutrition using milk, yoghurt, and cheese in older adults in aged care homes is associated with reduced fractures and falls. However, these foods contain potentially atherogenic fats. We aimed to determine whether this intervention that increased dairy consumption to recommended levels adversely affects serum lipid profiles. METHOD AND RESULTS: This was a sub-group analysis of a 2-year cluster-randomised trial involving 60 aged care homes in Australia. Thirty intervention homes provided additional milk, yoghurt, and cheese on menus while 30 control homes continued with their usual menus. A sample of 159 intervention and 86 controls residents (69% female, median age 87.8 years) had dietary intakes recorded using plate waste analysis and fasting serum lipids measured at baseline and 12 months. Diagnosis of cardiovascular disease and use of relevant medications were determined from medical records. Outcome measures were serum total, HDL and LDL cholesterol and ApoA-1 & B. Intervention increased daily dairy servings from 1.9 ± 1.0 to 3.5 ± 1.4 (p < 0.001) while controls continued daily intakes of ≤2 servings daily (1.7 ± 1.0 to 2.0 ± 1.0 (p = 0.028). No group differences were observed for serum total cholesterol/high-density lipoprotein-C (TC/HDL-C) ratio, Apoprotein B/Apoprotein A-1 (ApoB/ApoA-1) ratio, low-density lipoprotein-C (LDL-C), non-HDL-C, or triglycerides (TGs) at 12 months. CONCLUSION: Among older adults in aged care homes, correcting insufficiency in intakes of calcium and protein using milk, yoghurt and cheese does not alter serum lipid levels, suggesting that this is a suitable intervention for reducing the risk of falls and fractures. CLINICAL TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry (ACTRN12613000228785) 2012; https://www.anzctr.org.au.

Exploratory analysis of swallowing behaviour in community-dwelling older adults using a wearable device: Differences by age and ingestant under different task loads.

Objective: To develop a new method of evaluating swallowing behaviour. Methods: Sixty-nine healthy participants were divided into a younger (16 males and 16 females, mean age 39.09 ± 12.16 years) and older (18 males and 19 females, mean age 71.43 ± 5.50 years) group. The participants ingested water and yoghurt twice (directed and free swallowing) at rest and after performing simple daily life tasks (calculation and exercise). To measure swallowing frequency, we employed a smartphone-based, portable and neck-worn swallowing-sound-monitoring device. This device monitors swallowing behaviour continuously by collecting biological sounds from the neck without imposing behavioural restrictions. A neural network model of swallowing sound identification by deep learning was used for the subsequent evaluation. This device was used to obtain two types of saliva-swallowing sounds associated with different ingestants, at rest and after performing a stimulating task. Furthermore, we assessed the associated subjective psychological states. Results: The younger group showed a higher directed swallowing frequency (for both water and yoghurt) than the older group did. Regarding the type of ingestant, the swallowing frequency for yoghurt was higher during free swallowing in both the young and the older groups. 'Feeling calm' was reported significantly more often in the older group after swallowing yoghurt following exercise. Conclusions: Swallowing status in daily life was measured non-invasively using a wearable mobile device. It is important to consider the type of ingestant, daily living activities, and age when assessing swallowing.

The Physicochemical, Textural, Microbiological and Sensory Properties of Skimmed Buffalo Milk Yoghurt with Tragacanth Gum During Storage.

Research background: In the food industry, research interest in the functional effects of natural polysaccharides from plants has increased in recent years. Tragacanth gum is used in dairy products because of its stabilising, thickening, fat-replacing and prebiotic properties. However, skimmed milk is considered a significant commercial loss in the production of buffalo clotted cream. Therefore, the aim of the present study is to investigate the potential of tragacanth gum in the production of yoghurt from buffalo milk residues with different concentrations of tragacanth gum (0.5, 1 and 1.5 g/L). Experimental approach: Skimmed buffalo milk with different concentrations of tragacanth gum was pasteurised and, after cooling at 45 °C, a starter culture was added to each sample. All samples were fermented to a pH=4.80±0.2. The gross composition, acidity, water activity, water-holding capacity, whey separation, mass fractions of organic acids and volatile aroma compounds, counts of total aerobic mesophilic bacteria, yeasts and moulds, Lactococcus spp. and Lactobacillus spp. as well as sensory and textural properties were analysed during 15 days storage. Results and conclusions: The results showed that the use of tragacanth gum increased the dry matter mass fraction, water-holding capacity and mass fraction of proteins in the samples, while whey separation decreased as the concentration of gum increased. The addition of gum improved textural properties and hardness of the yoghurt. In terms of consistency, the sample with 1 g/L tragacanth gum was the most reliable. In the control group, the total aerobic mesophilic bacteria count was highest on the first and last day of storage. According to the results of the sensory evaluation, the sample with 0.5 g/L tragacanth gum was the most favourable. Novelty and scientific contribution: Research has shown that the use of stabilisers in varying ratios improves the quality of yoghurt made from fat-free buffalo milk, which is a by-product of industrial production. So instead of ending up as industrial waste, it is recycled and its value is increased.

Optimised Formulation of a New Sweet Apricot Kernel-Enriched Yoghurt: Assessment of Physicochemical, Sensory and Antioxidant Properties.

Research background: The addition of sweet apricot kernel powder, a by-product of apricot processing, to yoghurt appears to be particularly interesting option for the innovation of new food products. This study focuses on the formulation of a novel yoghurt enriched with sweet apricot kernel powder, sugar and milk powder. Experimental approach: Different yoghurts were prepared by mixing sweet apricot kernel powder, sugar and milk powder as ingredients based on the simplex-centroid mixture design. The optimisation process took into account the physicochemical, antioxidant and sensory properties of the yoghurt. Results and conclusions: The results showed that the optimum values of sugar, milk powder and apricot kernel powder were 3.07, 2.16 and 2.77 %, respectively. The physicochemical assays showed that the addition of apricot kernel powder led to a significant increase in total phenolic content, antioxidant activity, syneresis, viscosity and acidity. The addition of sugar and milk powder also had a significant effect on the taste, texture and consistency of the yoghurt. Moreover, the enrichment of the product with apricot kernel powder significantly influenced the colour, odour, taste, texture and consistency. In conclusion, the optimised yoghurt enriched with apricot kernel had an interesting phenolic content and antioxidant properties with sensory acceptability, while reducing the amount of sugar and milk powder. This confirms the potential of using sweet apricot kernels as an ingredient in yoghurt production. Novelty and scientific contribution: The use of a simplex-centroid mixture design to optimise a new yoghurt formulation enriched with sweet apricot kernels shows significant improvements in total phenolic content, antioxidant activity and sensory acceptability. In addition, less sugar and milk powder is needed. The addition of sweet apricot kernels to yoghurt is therefore a new approach to improving its nutritional value and sensory appeal.

Encapsulation of debittered pomelo juice using novel Moringa oleifera exudate for enrichment of yoghurt: A techno-functional approach.

Debittering of pomelo juice was conducted using 3.7 g of activated resin, resulting in a 36.8% reduction in bitterness without affecting the bioactive properties of juice. The debittered juice was then encapsulated with Moringa oleifera exudate at various ratios (1-5%), yielding a powder with a slightly rough surface. Total phenol content (TPC) increased by 46-56% compared to the debittered juice. Functional yoghurt containing encapsulates at concentrations of 1% and 2% demonstrated that the 2% concentration led to longer storage duration, resulting in increased acidity and syneresis compared to the control. TPC of the yoghurt (161.89-198.22 µg Gallic acid equivalent (GAE)/g) remained significantly higher (p < 0.05) than that of the control (47.15 µg GAE/g) and acacia gum-based yoghurt (141.89-171.37 µg GAE/g), decreasing with storage duration. Addition of encapsulates significantly altered the yoghurt's texture, resulting in lower firmness (0.57 to 0.64 N) compared to the control, while adhesiveness values remained comparable (6.33 to 6.25 g.s). The highest values of G' and G" were observed in samples containing 2% encapsulates with moringa compared to those with acacia gum. This study suggests potential avenues for further exploration in functional foods with enhanced health benefits.

Development of optimized functional clove fortified probiotic yoghurt.

We focused on assessing the antimicrobial effects of functional yoghurts supplemented with clove and probiotics. The formulation of aqueous clove extract (ACE) incorporated with probiotic yoghurt (Streptococcus thermophilus, Lactobacillus bulgaricus, and Lactococcus lactis) was optimised in terms of aqueous clove extract concentrations (2.5-7.5% v/v), fermentation temperature (32-42 °C), and total culture concentration (1.5-4.5% v/v). pH, titratable acidity, syneresis, water holding capacity, viscosity, springiness, color difference, lactic acid bacteria viability, and the antibacterial property of 17 runs were determined as responses using Box-Behnken design. The results indicate that elevated ACE concentration leads to a significant (p < 0.05) increase in titratable acidity, antibacterial effectiveness (against K. pneumoniae and P. aeruginosa), springiness, and color profile. Conversely, an elevated fermentation temperature significantly (p < 0.05) reduces pH and L. bulgaricus viability (log CFU/mL). Additionally, there is a significant (p < 0.05) decline in S. thermophilus and L. lactis viability (log CFU/mL) as well as springiness with an increased culture concentration. The optimal conditions identified are 7.5% (v/v) ACE concentration, a fermentation temperature of 36.6 °C (37 °C), and a total culture concentration of 4.5% (v/v), resulting in a 79% desirability score. The spectra of components were mainly obtained at wavelength of 3258 cm-1, 1636 cm-1 and 1075 cm-1 in Fourier transform infrared (FTIR) spectroscopy of optimized functional yoghurt. Where, 3258 cm-1 corresponds to the stretching vibration of O-H (hydroxyl) groups, 1636 cm-1 corresponds to the C=O (carbonyl) stretching vibration, and 1075 cm-1 corresponds to the C-O (ether or alcohol) stretching vibration.

The Effect of High-Pressure Processing of Caprine Milk on the Production and Properties of Yoghurt.

The aim of this study was to determine the suitability of HP-treated caprine milk for yoghurt production and to evaluate the effect of HP treatment on yoghurt properties. Reconstituted caprine milk was subjected to HP treatment (350 MPa/10 min/20 °C); a lactic acid starter culture (YC-X16, Chr. Hansen) was added. Milk was fermented at a temperature of 43 °C until pH 4.60. Bacterial counts, pH, color, rheological characteristics, texture, microstructure, and the sensory attributes of the yoghurt were determined after production and after seven days of storage at a temperature of 4 °C. HP treatment increased color saturation and whiteness index and induced a minor increase in milk pH. Minor differences in the acidification curve were noted. During storage, Streptococcus thermophilus counts were significantly higher in yoghurt from HP-treated than from untreated milk, whereas Lactobacillus delbruecki ssp. bulgaricus counts remained stable. A color analysis did not reveal differences between the experimental and control yoghurts. After storage, yoghurt made from HP-treated milk was characterized by thicker consistency and lower rheological stability than the control yoghurt. The micrographs of the yoghurts confirmed the differences in rheological parameters. Yoghurt produced from HP-treated caprine milk and stored for seven days received the highest scores in the sensory evaluation.

Natural approach of using nisin and its nanoform as food bio-preservatives against methicillin resistant Staphylococcus aureus and E.coli O157:H7 in yoghurt.

BACKGROUND: Natural antimicrobial agents such as nisin were used to control the growth of foodborne pathogens in dairy products. The current study aimed to examine the inhibitory effect of pure nisin and nisin nanoparticles (nisin NPs) against methicillin resistant Staphylococcus aureus (MRSA) and E.coli O157:H7 during the manufacturing and storage of yoghurt. Nisin NPs were prepared using new, natural, and safe nano-precipitation method by acetic acid. The prepared NPs were characterized using zeta-sizer and transmission electron microscopy (TEM). In addition, the cytotoxicity of nisin NPs on vero cells was assessed using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The minimum inhibitory concentrations (MICs) of nisin and its nanoparticles were determined using agar well-diffusion method. Further, fresh buffalo's milk was inoculated with MRSA or E.coli O157:H7 (1 × 106 CFU/ml) with the addition of either nisin or nisin NPs, and then the inoculated milk was used for yoghurt making. The organoleptic properties, pH and bacterial load of the obtained yoghurt were evaluated during storage in comparison to control group. RESULTS: The obtained results showed a strong antibacterial activity of nisin NPs (0.125 mg/mL) against MRSA and E.coli O157:H7 in comparison with control and pure nisin groups. Notably, complete eradication of MRSA and E.coli O157:H7 was observed in yoghurt formulated with nisin NPs after 24 h and 5th day of storage, respectively. The shelf life of yoghurt inoculated with nisin nanoparticles was extended than those manufactured without addition of such nanoparticles. CONCLUSIONS: Overall, the present study indicated that the addition of nisin NPs during processing of yoghurt could be a useful tool for food preservation against MRSA and E.coli O157:H7 in dairy industry.

Cholesterol and Its Oxidation Derivatives Content in Market Dairy Products.

Cholesterol oxidation products (COPs) are contaminants of food of animal origin. Increased levels of these compounds in the human body are associated with an increased risk of many non-communicable diseases. Dairy products are mentioned among the main sources of these compounds in the diet. The objective of this study was to evaluate the contents of cholesterol and its oxidized derivatives in eleven groups of dairy products, willingly consumed in European countries. The levels of COPs were determined by applying the GC-TOF/MS method. In the tested products, cholesterol and its oxidation derivatives, such as 7-ketocholesterol, 7α-hydroxycholesterol, 7ß-hydroxycholesterol, 5,6ß-epoxycholesterol and 5,6α-epoxycholesterol, were determined. The studied dairy products differed in their contents and profiles of oxysterols. The highest contents of COPs were found in cheese with internal mold (13.8 ± 2.5 mg kg-1) and Cheddar (11.7 ± 3.5 mg kg-1), while the lowest levels were detected in yoghurt (0.94 ± 0.30 mg kg-1) and kefir (0.57 ± 0.11 mg kg-1). 7-ketocholesterol and 5,6ß-epoxycholesterol were the dominant oxysterols. The ratio of oxidized derivatives to total cholesterol was on average 1.7%. Our results confirmed that dairy products are an important dietary source of COPs. Their levels should be monitored in dairy products to provide the best health quality.

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.

A unique implementation of Hantzsch reaction for determination of natamycin in Yoghurt: Hyphenated with Box-Behnken-design for optimization.

This study aims to develop a novel and selective method for the detection of natamycin (E235) in yoghurt. The suggested method adopts an application of Hantzsch reaction to turn on the fluorescence behavior of natamycin (blue fluorescence), allowing its sensitive and selective determination in yoghurt samples without any overlapping at 485 nm. The originality of the research lies in the fact that this application takes place for the first time, also the detection (LOD) and quantification (LOQ) limits were very low (0.02 and 0.06µg mL-1, respectively) with a linear concentration range of 0.1-1.0 µgmL-1. Moreover, the developed method was employed for the detection of E235 in yoghurt sample with a good recoveries (98.80 ± 1.20-99.20 ± 1.15 (%), over a concentration range of 0.5-1.0 µgmL-1, (LOD = 0.04 and LOQ = 0.12 µgmL-1). Furthermore, the specificity and convenient application of our intended method is an attempt to determine E235 in milk anddairy products with easily followable steps.

A Metabolomics Approach to Establish the Relationship between the Techno-Functional Properties and Metabolome of Indian Goat Yoghurt.

INTRODUCTION: Goat milk has poorer fermentation characteristics due to the absence or only traces of αs1-casein, due to which goat yoghurt contains a less dense gel structure. Moreover, the fermentation characteristics of the milk vary between the breeds of the same species. Therefore, it becomes imperative to explore a few metabolites which could regulate the techno-functional properties of goat yoghurt. OBJECTIVES: This study was aimed at relating the metabolite profile of yoghurt prepared from milk of Barbari, an indigenous goat breed of India, and its techno-functional properties (firmness, whey syneresis, and flow behaviour) using multivariate data analysis and regression models. RESULTS: Goat yoghurt was prepared with two different total solids (TS) levels (12 and 16%) and cultures, namely, commercial culture comprising a thermophilic yoghurt culture (A) and NCDC-263 comprising a mixed yoghurt culture (B). Results demonstrated a significant difference (p < 0.05) in whey syneresis with the increase in the TS level. Flow behaviour of all yoghurt samples showed a decrease in viscosity with an increase in shear rate, which confirmed its non-Newtonian behaviour and shear thinning nature, whereas frequency sweep confirmed its viscoelastic nature. Firmness was the most affected under the influence of different TS and culture levels. It was higher (p < 0.05) for 16-A, followed by 16-3B, and minimum for 12-2B. GC-MS-based metabolomics of the yoghurt revealed a total of 102 metabolites, out of which 15 metabolites were differentially expressed (p < 0.05), including 2-hydroxyethyl palmitate, alpha-mannobiose, and myo-inositol. Multivariate data analysis revealed clear separation among groups using principal component analysis and several correlations using a correlation heat map. Further, regression analysis exhibited methylamine (0.669) and myo-inositol (0.947) with higher regression coefficients (R2 values) exceeding 0.6, thus demonstrating their significant influence on the techno-functional properties, mainly firmness, of the yogurt. CONCLUSION: In conclusion, A gas chromatography-based metabolomics approach could successfully establish a relationship between the metabolome and the techno-functional properties of the yoghurt.