Development of yogurt fortified with four varieties of common bean (Phaseolus vulgaris) whey by using response surface methodology: a preliminary study

In recent years, there has been a growing interest in developing novel foods with improved health and nutritional characteristics, particularly through the supplementation and development of dairy products with plant-based ingredients. In this study, the response surface methodology (RSM) was employed to optimize the ingredient formulation and processing parameters of common bean whey-fortified yogurt (CBWFY) production containing Lactobacillus bulgaricus, and common bean whey (CBW) with a high probiotic count, superior physicochemical and textural properties, and desirable sensory attributes. The experiments were planned using the "box-Behnken design" (BBD) with three independent variables: fermentation time (0-10 h), common bean ratio (25-100%), and the amount of starter culture (1-5%). To assess the physicochemical properties of the yogurt, such as pH, titratable acidity, viable cell count, and syneresis of the CBWFY, they were determined and optimized. In all the common bean whey samples, the optimum conditions were obtained by supplementing cow milk with 25% common bean whey (CBW), an inoculation ratio of 1-4%, and fermentation for 5.54 h. Fermentation time and CBW concentration significantly affected the viability of L. bulgaricus and the physicochemical attributes of yogurt. This study demonstrated that the addition of cow milk with 25% CBW from the white bean variety produced probiotic yogurt with the highest L. bulgaricus population (up to 8.55 log CFU/mL) compared to the other varieties and an enhancement in the yogurt's pH and acidity, while a decrease in yogurt syneresis occurred. In general, the results of the current study showed that adding up to 25% white common bean whey to probiotic yogurt can be an option for producing yogurt with potential functional and sensory quality.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05876-z.

Polysaccharides from Brasenia schreberi with Great Antioxidant Ability and the Potential Application in Yogurt

Brasenia schreberi is a widely consumed aquatic plant, yet the knowledge regarding its bioactive components, particularly polysaccharides, remains limited. Therefore, this study aimed to optimize the extraction process of polysaccharides from B. schreberi using the response surface method (RSM). Additionally, we characterized the polysaccharides using various methods and assessed their antioxidant capabilities both in vitro and in vivo, employing cell cultures and Caenorhabditis elegans. Furthermore, these polysaccharides were incorporated into a unique yogurt formulation. Our findings demonstrated that hot water extraction was the most suitable method for extracting polysaccharides from B. schreberi, yielding samples with high sugar content, significant antioxidant capacity, and a well-defined spatial structure. Moreover, pectinase was employed for polysaccharide digestion, achieving an enzymolysis rate of 10.02% under optimized conditions using RSM. Notably, the results indicated that these polysaccharides could protect cells from oxidative stress by reducing apoptosis. Surprisingly, at a concentration of 250 μg/mL, the polysaccharides significantly increased the survival rate of C. elegans from 31.05% to 82.3%. Further qPCR results revealed that the polysaccharides protected C. elegans by up-regulating the daf-16 gene and down-regulating mTOR and insulin pathways, demonstrating remarkable antioxidant abilities. Upon addition to the yogurt, the polysaccharides significantly enhanced the water retention, viscosity, and viability of lactic acid bacteria. These outcomes underscore the potential of polysaccharides from B. schreberi as a valuable addition to novel yogurt formulations, thereby providing additional theoretical support for the utilization of B. schreberi.

Sweeteners in food samples: An update on pretreatment and analysis techniques since 2015

Sweeteners play an irreplaceable role in daily life and have been found in multitudinous food products. However, excessive or unreasonable intake of sweeteners as food additives brings about untoward problems due to the accumulation in the human body. Therefore, a comprehensive review of different sweeteners' pretreatment and determination methods is urgently needed. In this review, we comprehensively reviewed the progress of different pretreatment and detection methods for sweeteners in various food, focusing on the latest development since 2015. Current state-of-the-art technologies, such as headspace single-drop microextraction, ultrasound-assisted emulsification microextraction, solid-phase microextraction, two-dimensional liquid chromatography, and high-resolution mass spectrometry, are thoroughly discussed. The advantages, disadvantages, critical comments, and future perspectives are also proposed. This review is expected to provide rewarding insights into the future development and broad application of pretreatment and detection methods for sweeteners in different food samples.

The Impact of Sweetener Type on Physicochemical Properties, Antioxidant Activity and Rheology of Guava Nectar during Storage Time

This study aimed to evaluate the differences in physicochemical properties, antioxidant properties, and rheology between guava nectar with sucrose and guava nectar with neotame and stevia addition (0.01% and 0.05%). All parameters were investigated during refrigerated storage at 4 °C for 15 days. The result showed that all sweetened guava juice samples led to the juice with the greatest presence of overall appearance and antioxidant property. The flow behavior of sweetened guava juice was shear-thinning which was not different from guava juice without sweetener. However, the major volatile flavor compounds identified in all guava juice samples were β-caryophyllene, α-caryophyllene, bisabolene, aromadendrene, α-humulene, and nerolidol, which is not different from guava juice without sweeteners during storage. It indicated that stevia and neotame are good alternative sweeteners to produce low caloric juice production.

An Overview of Sensory Characterization Techniques: From Classical Descriptive Analysis to the Emergence of Novel Profiling Methods

Sensory science provides objective information about the consumer understanding of a product, the acceptance or rejection of stimuli, and the description of the emotions evoked. It is possible to answer how consumers perceive a product through discriminative and descriptive techniques. However, perception can change over time, and these fluctuations can be measured with time-intensity methods. Instrumental sensory devices and immersive techniques are gaining headway as sensory profiling techniques. The authors of this paper critically review sensory techniques from classical descriptive analysis to the emergence of novel profiling methods. Though research has been done in the creation of new sensory methods and comparison of those methods, little attention has been given to the timeline approach and its advantages and challenges. This study aimed to gather, explain, simplify, and discuss the evolution of sensory techniques.

Physicochemical and microbiological characteristics of camel milk yogurt as influenced by monk fruit sweetener

Camel milk, similar to cow milk, contains all of the essential nutrients as well as potentially health-beneficial compounds with anticarcinogenic, antihypertensive, and antioxidant properties. Camel milk has been used for the treatment of allergies to cow milk, diabetes, and autism. Camel milk helps decrease cholesterol levels in blood and improves metabolism. One of the most desirable food tastes is sweetness. However, the excessive ingestion of sugar negatively affects human health. Monk fruit sweetener is a natural, 0-calorie sweetener with many health-beneficial functions. Monk fruit sweetener helps decrease symptoms of asthma and diabetes, prevents oxidation and cancer, protects the liver, regulates immune function, and lowers glucose levels. Monk fruit sweetener is 100 to 250 times sweeter than sucrose. The objective of this study was to examine the influence of different concentrations of monk fruit sweetener on the physicochemical properties and microbiological counts of drinking yogurt made from camel milk. Camel milk drinking yogurt was produced with 0, 0.42, 1.27, and 2.54 g/L of monk fruit sweetener and stored for 42 d. The physicochemical characteristics and microbiological counts of yogurts were measured at d 1, 7, 14, 21, 28, 35, and 42. For the physicochemical characteristics, pH, titratable acidity, viscosity, and color [lightness-darkness (L*), red-green axis (a*), yellow-blue axis (b*), chroma (C*), and hue angle (h*)] values were evaluated. The counts of Streptococcus thermophilus, Lactobacillus bulgaricus, Lactobacillus acidophilus, coliforms, and yeast and mold were determined. Three replications were conducted. The sweetener addition significantly influenced pH, viscosity, and color (a*, b*, C*, and h*) values. Control samples had significantly higher pH values, lower viscosity, lower b* and C* values, and higher h* values than the samples with 1.27 and 2.54 g/L of monk fruit sweetener. Growth of S. thermophilus, L. bulgaricus, and probiotic culture L. acidophilus was not affected by the incorporation of monk fruit sweetener. Monk fruit sweetener can be added in camel milk yogurts as a health-beneficial 0-calorie sweetener.

Strategies for lowering the added sugar in yogurts

The rising awareness about the adverse health effects of high sugar consumption has led to regulatory amendments for triggering sugar reduction in food products. Sugar reduction in yogurt is a challenging endeavor due to the changes in taste, flavor, texture, maintenance of food functionality, shelf-life, cost and consumer acceptability. A review of the scientific literature, patents, and web articles revealed several approaches being explored by the dairy industry to reduce the sugar addition. A careful assessment of these strategies and their critical analysis is presented in this review. The strategies for sugar reduction involve multifaceted approaches including the use of alternative low-calorie sweeteners, honey, fruit preparations, novel cultures, lactase addition, inulin fiber addition, and flavor interventions. Much of the work so far has focused on development of low-calorie alternative sweeteners, and novel sweeteners-based solutions are evolving. The use of food structuring approaches remains to be explored for sugar reduction in yogurt.

Gelation and microstructural properties of a millet-based yogurt-like product using polymerized whey protein and xanthan gum as thickening agents

Cereal-based fermented products are becoming popular in the world. A millet-based yogurt-like product (MYP) using polymerized whey protein (PWP) and xanthan gum (XG) as thickeners was developed. The present study aimed to investigate the effects of PWP (0.3 to 0.5%, w/v) and XG (0 to 0.2%, w/v) on the gelation properties and microstructure of MYP. All samples were analyzed for rheological properties, textural properties, microstructure, and pH value during fermentation. The MYP Ⅲ (0.4% PWP and 0.1% XG) registered the highest elastic modulus (G') throughout the fermentation and cooling steps (P < 0.05), but MYP Ⅳ (0.35% PWP and 0.15% XG) had the highest apparent viscosity compared with the other samples. No significant differences in the pH values among the samples were observed during the fermentation process (P > 0.05). The hardness value of MYP Ⅳ reached a maximum after 4 hr and then stabilized during fermentation. Scanning electron microscopy showed a compact and uniform network for the MYP with PWP and XG. MYP Ⅳ had the best texture properties (hardness, springiness, and gumminess). Overall, PWP (0.35%, w/v) and XG (0.15%, w/v) were the best combination for MYP as a thickening system. PRACTICAL APPLICATION: Cereal-based fermented products have attracted much attention in the food industry. However, due to absence of a natural protein network, it is hard to produce a set-type millet-based yogurt with a firm texture under the studied conditions without adding any thickening agents. In this study, PWP (0.35%, w/v) and XG (0.15%, w/v) can be used for fermentation of millet-based yogurt-like products. The new cereal-based fermented product would be a promising food in the market.

Physiochemical, rheological, microstructural, and antioxidant properties of yogurt using monk fruit extract as a sweetener

A yogurt using monk fruit extract (MFE) as a sweetener was developed. The aim of the study was to investigate the viability of using MFE to develop sweetened yogurts without the calories of added sugar. The physiochemical, rheological, microstructural, and antioxidant properties of yogurt were studied. Rheological results showed that MFE affected the yogurt fermentation process and its rheological properties. Yogurt sweetened with MFE had similar microstructural properties to yogurt sweetened with sucrose. Yogurt with MFE showed higher levels of gly-pro-p-nitroanilide and dipeptidyl peptidase IV inhibitory activities, 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity, α-glucosidase inhibitory activities, and superoxide anion radical scavenging ability compared with other yogurt samples. Results indicated that MFE could be a novel sweetener and a food antioxidant for functional yogurt and related products.

High-level production of single chain monellin mutants with enhanced sweetness and stability in tobacco chloroplasts

MAIN CONCLUSION

Plastid-based MNEI protein mutants retain the structure, stability and sweetness of their bacterial counterparts, confirming the attractiveness of the plastid transformation technology for high-yield production of recombinant proteins. The prevalence of obesity and diabetes has dramatically increased the industrial demand for the development and use of alternatives to sugar and traditional sweeteners. Sweet proteins, such as MNEI, a single chain derivative of monellin, are the most promising candidates for industrial applications. In this work, we describe the use of tobacco chloroplasts as a stable plant expression platform to produce three MNEI protein mutants with improved taste profile and stability. All plant-based proteins were correctly expressed in tobacco chloroplasts, purified and subjected to in-depth chemical and sensory analyses. Recombinant MNEI mutants showed a protein yield ranging from 5% to more than 50% of total soluble proteins, which, to date, represents the highest accumulation level of MNEI mutants in plants. Comparative analyses demonstrated the high similarity, in terms of structure, stability and function, of the proteins produced in plant chloroplasts and bacteria. The high yield and the extreme sweetness perceived for the plant-derived proteins prove that plastid transformation technology is a safe, stable and cost-effective production platform for low-calorie sweeteners, with an estimated production of up to 25-30 mg of pure protein/plant.

Comparison of rapid descriptive sensory methodologies: Free-Choice Profiling, Flash Profile and modified Flash Profile

Rapid sensory methods have been developed as alternatives to traditional sensory descriptive analysis methods. Among them, Free-Choice Profiling (FCP) and Flash Profile (FP) are two that have been known for many years. The objectives of this work were to compare the rating-based FCP and ranking-based FP method; to evaluate the impact of adding adjustments to FP approach; to investigate the influence of the number of assessors on the outcome of modified FP. To achieve these aims, a conventional descriptive analysis (DA), FCP, FP and a modified version of FP were carried out. Red wines made by different grape maturity and ethanol concentration were used for sensory testing. This study showed that DA provided a more detailed and accurate information on products through a quantitative measure of the intensity of sensory attributes than FCP and FP. However, the panel hours for conducting DA were higher than that for rapid methods, and FP was even able to separate the samples to a higher degree than DA. When comparing FCP and FP, this study showed that the ranking-based FP provided a clearer separation of samples than rating-based FCP, but the latter was an easier task for most assessors. When restricting assessors on their use of attributes in FP, the sample space became clearer and the ranking task was simplified. The FP protocol with restricted attribute sets seems to be a promising approach for efficient screening of sensory properties in wine. When increasing the number of assessors from 10 to 20 for conducting the modified FP, the outcome tended to be slightly more stable, however, one should consider the degree of panel training when deciding the optimal number of assessors for conducting FP.