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

High performance poly(L-lactic acid)-based film by one-step synthesis of poly (L-lactic acid-co-butylene itaconate-co-glycolic acid) for efficient preservation of yogurt storage

Biodegradable poly(L-lactic acid) (PLLA) has seldom used for dairy packaging due to medium permeability and brittleness. Novel PLLA copolymers, poly (L-lactic acid-co-butylene itaconate-co-glycolic acid) (PLBIGA), were developed by integrating glycolic acid (GA) and poly(butylene itaconate) (PBI) into PLLA's structure using low molecular weight PLLA as a key initiator. Then, packaging materials with better barrier and mechanical properties were obtained by blended PLBIGA with PLLA. Both PLLA/PLBIGA films and polyethylene nylon composite film (PE/NY) were used for stirred yogurt packaging and storage at 4 °C for 25 days. Results revealed that yogurt packed by PLLA/PLBIGA films maintained stabler water-holding capacity, color, and viscosity over the storage period. Moreover, the integrity of the gel structure and the total viable count of lactic acid bacteria in yogurt packaged in PLLA/40-PLBIGA8 were also found to be superior to those in PE/NY packages, highlighting its eco-friendly advantages in dairy packaging.

Siraitia grosvenorii As a Homologue of Food and Medicine: A Review of Biological Activity, Mechanisms of Action, Synthetic Biology, and Applications in Future Food

Siraitia grosvenorii (SG), also known as Luo Han Guo or Monk fruit, boasts a significant history in food and medicine. This review delves into SG's historical role and varied applications in traditional Chinese culture, examining its phytochemical composition and the health benefits of its bioactive compounds. It further explores SG's biological activities, including antioxidant, anti-inflammatory, and antidiabetic properties and elucidates the mechanisms behind these effects. The review also highlights recent synthetic biology advances in enhancing the production of SG's bioactive compounds, presenting new opportunities for broadening their availability. Ultimately, this review emphasizes SG's value in food and medicine, showcasing its historical and cultural importance, phytochemistry, biological functions, action mechanisms, and the role of synthetic biology in its sustainable use.

A review on natural sweeteners, sweet taste modulators and bitter masking compounds: structure-activity strategies for the discovery of novel taste molecules

Growing demand for the tasty and healthy food has driven the development of low-calorie sweeteners, sweet taste modulators, and bitter masking compounds originated from natural sources. With the discovery of human taste receptors, increasing numbers of sweet taste modulators have been identified through human taste response and molecular docking techniques. However, the discovery of novel taste-active molecules in nature can be accelerated by using advanced spectrometry technologies based on structure-activity relationships (SARs). SARs explain why structurally similar compounds can elicit similar taste qualities. Given the characterization of structural information from reported data, strategies employing SAR techniques to find structurally similar compounds become an innovative approach to expand knowledge of sweeteners. This review aims to summarize the structural patterns of known natural non-nutritive sweeteners, sweet taste enhancers, and bitter masking compounds. Innovative SAR-based approaches to explore sweetener derivatives are also discussed. Most sweet-tasting flavonoids belong to either the flavanonols or the dihydrochalcones and known bitter masking molecules are flavanones. Based on SAR findings that structural similarities are related to the sensory properties, innovative methodologies described in this paper can be applied to screen and discover the derivatives of taste-active compounds or potential taste modulators.

Effect of Whole Egg Liquid on Physicochemical, Quality, Fermentation and Sensory Characteristics of Yogurt

With the purpose of developing an alternative set yogurt with high consumer acceptability, liquid whole egg (LWE), at levels that varied from 0 to 30%, was incorporated into set yogurt, and the effects on the physicochemical, quality, fermentation, and sensory characteristics of yogurt were evaluated. The fat content was lower in egg yogurt than in control yogurt. All color variables were significantly affected by LWE amount. The amount of bacteria in the egg yogurt was greater than in the control yogurt. Sensory analysis data suggested that color, odor, and texture consistently impacted the overall acceptability of the egg yogurt. The addition of 5% whole egg, which resulted in an increase of 6.28-fold in hardness, increase of 6.1-fold in viscosity, decrease in pH values, and a 5.6% decline in water-holding capacity (WHC). The aroma and flavor of the set yogurt was improved as well. LWE addition significantly increased the protein content and dynamic rheology. More importantly, the addition of LWE increased the protein content of the set yogurt. This investigation demonstrated the feasibility of fabricating LWE-enriched set yogurt and its superior quality compared with the corresponding normal product. It also emphasized the reconstruction of LWE with enhanced properties.

Low Fat Yoghurts Produced with Different Protein Levels and Alternative Natural Sweeteners

The food industry is looking for substitutes for sucrose in food items due to the excessive consumption of products with added sugar and the demand for healthier products. Alternative natural sweeteners can help achieve this goal. Different types of low-fat yoghurts (1% fat), with low-protein and high-protein levels (3% and 4.5-6.5% protein, respectively), were produced using alternative natural sweeteners. The low-protein yoghurts were made with stevia (0.03% w/w) or agave syrup (4.5% w/w). The high-protein yoghurts were made with stevia (0.04% w/w), xylitol (6% w/w) or honey (6% w/w). Sucrose (6% w/w) was used as a control in both trials. pH and titratable acidity, CIEL*a*b* color parameters, syneresis index, rheology and the texture profile of the low-fat yoghurts were evaluated over refrigerated storage. All products underwent sensory evaluation by an untrained panel. The high-protein yoghurts were found to be more acidic (>1% as lactic acid), had a lower syneresis index (between 2.1 and 16.2%) and a better consistency (stronger gel structure) than the low-protein yoghurts. In terms of rheological parameters, stevia-sweetened yoghurts scored higher than the other sweetened yoghurts, showing a better gel structure. The different sweeteners tested did not significantly affect the sensory properties of the yoghurts, although the high-protein yoghurts scored higher for most of the attributes evaluated. Overall, consumers preferred stevia-sweetened yoghurts to yoghurts sweetened with sucrose or agave for the low-protein yoghurts. Of the tested formulations, those containing high protein with the alternative natural sweetener xylitol received higher scores in all attributes. These results reveal the potential of the tested natural sweeteners as sucrose substitutes, while contributing to improving the nutritional value of yoghurts.

Application of natural and modified additives in yogurt formulation: types, production, and rheological and nutraceutical benefits

Yogurt, a popular fermented dairy product, is of different types and known for its nutritional and nutraceutical benefits. However, incorporating additives into yogurt has been adopted to improve its functionality and nutraceutical properties. Additives incorporated in yogurt may be natural or modified. The incorporation of diverse natural additives in yogurt formulation, such as moringa, date palm, grape seeds and argel leaf extracts, cornelian cherry paste, mulberry fruit and leaf powder, lentil flour, different types of fibers, lemongrass and spearmint essential oils, and honey, has been reported. Similarly, modified additives, such as β-glucan, pectin, inulin, sodium alginate, and gelatin, are also added to enhance the physicochemical, textural, sensory, and rheological properties of yogurt. Although additives are traditionally added for their technological impact on the yogurt, studies have shown that they influence the nutritional and nutraceutical properties of yogurt, when added. Hence, yogurts enriched with functional additives, especially natural additives, have been reported to possess an improved nutritional quality and impart several health benefits to consumers. These benefits include reducing the risk of cardiovascular disease, cancer, osteoporosis, oxidative stress, and hyperglycemia. This current review highlights the common types of yogurt, the production process, and the rheological and nutraceutical benefits of incorporating natural and modified additives into yogurt.

Analysis of metabolites of bactrain camel milk in Alxa of China before and after fermentation with fermenting agent TR1 based on untargeted LC-MS/MS based metabolomics

Camel milk produces many beneficial functional compounds and affects body health through metabolism. The differential metabolites of bactrain camel milk in Alxa before and after fermentation were identified by liquid chromatography-tandem mass spectrometry based metabolomics (LC-MS/MS). The differential metabolite pathway types were also identified in this paper. We obtained the following results that 148 and 82 differential metabolites were detected in positive and negative ion mode respectively, 85 differential metabolites were shown a significant upward trend and 63 with downward trend after fermentation in positive ion mode. Meanwhile, 32 differential metabolites characterized upward trend and 50 characterized downward trend in negative ion mode. The differential metabolites were mainly organic acids, amino acids, esters, vitamins and other substances contained in camel milk. Among them, most up-regulated substances had the functions of lowering blood pressure, lowering blood sugar, treatment of inflammation, antibiosis and other effects. Many harmful substances were significantly down-regulated after camel milk fermentation. However, there were also some metabolites whose prebiotic functions have been weakened by camel milk fermentation, which may provide reference values for healthcare function, exploitation and application of camel milk.

Isolated Fraction of Gastric-Digested Camel Milk Yogurt with Carao (Cassia grandis) Pulp Fortification Enhances the Anti-Inflammatory Properties of HT-29 Human Intestinal Epithelial Cells

Functional foods have recently generated a lot of attention among consumers looking for healthy options. Studies have examined yogurt with carao to increase health benefits and probiotic characteristics. It has been determined that carao fruit and camel milk have high phenolic compound and antioxidant activity concentrations. The objective of this study was to examine if carao (0, 1.3, 2.65, and 5.3 g/L) incorporated into yogurt enhances anti-inflammatory stimulus and antioxidant activity and impacts the physio-chemical and sensory properties of camel milk yogurt. HT-29 cells were used as a model of anti-inflammatory response, including cytokine responses of IL-8 and mRNA production of IL-1β and TNF-α in gastric digested isolated fraction. In addition, pH, titratable acidity, Streptococcus thermophilus counts and Lactobacillus bulgaricus counts of camel yogurts were examined during the fermentation process in 0, 2.5, 5, and 7 h whereas viscosity, syneresis, and radical scavenging assay evaluations were determined at hour 7. Furthermore, a consumer study was performed. Compared to control samples, the incorporation of carao into yogurts did not lead to a significant (ρ > 0.05) difference in the pH. In contrast, titratable acidity (TA), viscosity, syneresis, and antioxidant capacity significantly increased with the inclusion of 2.65 and 5.3 g/L carao, while 5.3 g/L carao significantly (ρ < 0.05) increased the counts of both bacteria. The inflammatory response of IL-8 and the level of mRNA production of IL-1β and TNF-α was significantly (ρ < 0.05) lower with 2.65 and 5.3 g/L carao yogurt compared to control camel yogurt. Sensory attributes were not impacted by the addition of 1.3 and 2.65 g/L carao. Carao could be a possible ingredient to consider when improving the nutrition value of yogurt.

Assessment of the physicochemical and sensory characteristics of fermented camel milk fortified with Cordia myxa and its biological effects against oxidative stress and hyperlipidemia in rats

Natural feed additives and their potential benefits in production of safe and highly nutritious food have gained the attention of many researchers the last decades. Cordia myxa is a nutrient-dense food with various health benefits. Despite this fact, very limited studied investigated the physicochemical and sensory impacts of incorporation of fermented camel milk with Cordia myxa and its biological effects. The current study aimed to assess the physical, chemical, and sensory characteristics of fermented camel milk (FCM) fortified with 5, 10, and 15% Cordia myxa pulp. The study demonstrated that fortification of camel milk efficiently enhanced protein, total solids, ash, fiber, phenolic substance, and antioxidant activity. When compared to other treatments, FCM supplemented with 10% Cordia myxa pulp had the best sensory features. In addition, FCM fortified with 10% Cordia myxa pulp was investigated as a potential inhibitor of hypercholesterolemia agents in obese rats. Thirty-two male Wistar rats were split into two main groups including normal pellet group (n = 8) served as negative control group (G1) and a group of hyperlipidemic animals (n = 24) were feed on a high-fat diet (HFD). Hyperlipidemic rats group (n = 24) were then divided into three subgroups (8 per each); second group or positive control (G2) which include hyperlipidemic rats received distilled water (1 mL/day), the third group (G3) involved hyperlipidemic rats feed on FCM (10 g/day) and the fourth group (G4) included hyperlipidemic animals feed on 10 g/day FCM fortified with 10% of Cordia myxa pulp by oral treatment via an intestinal tube for another 4 weeks. In contrast to the positive control group, G4 treated with Cordia myxa showed a substantial decrease in malondialdehyde, LDL, cholesterol, triglycerides, AST, ALT, creatinine, and urea levels, while a significant increase in HDL, albumin, and total protein concentrations. The number of large adipocytes decreased while the number of small adipocytes increased after consumption of fortified FCM. The results indicated that fermented milk fortified with Cordia myxa pulp improved the functions of the liver and kidney in hyperlipidemic rats. These results demonstrated the protective effects of camel milk and Cordia myxa pulp against hyperlipidemia in rats.

A Review on Processing Opportunities for the Development of Camel Dairy Products

Camel milk has a significant and pivotal role in the diet of people residing in semi-arid and arid regions. Ever since ancient times, marketing of camel milk has remained insignificant due to nonexistence of processing amenities in the camel nurturing areas, hence the utilization of unprocessed camel milk has continuously remained limited at family level by the nomads. Due to the superior medicinal values and health promoting effects, incredible growth in the demand of camel milk and dairy products have been noticed all over the world during last two decades. Such emergence has led dairy industry to provide diversified camel dairy products to the consumers with superior nutritional and functional qualities. In contrast to bovine, very few food products derived from camel milk are available in the present market. With the advancements in food processing interventions, a wide range of dairy and non-dairy products could be obtained from camel milk, including milk powder, cheese, yogurt, ice cream, and even chocolate. In some regions, camel milk is used for traditional dishes such as fermented milk, camel milk tea, or as a base for soups and stews. Current review highlights the processing opportunities regarding the transformation of camel milk into various dairy products via decreasing the inherent functionality that could be achieved by optimization of processing conditions and alteration of chemical composition by using fortification method. Additionally, future research directions could be devised to improve the product quality.

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 Fermented Camel Milk Supplemented with Sidr Fruit (Ziziphus spina-christi L.) Pulp on Hyperglycemia in Streptozotocin-Induced Diabetic Rats

Diabetes is one of the most common chronic metabolic diseases, and its occurrence rate has increased in recent decades. Sidr (Ziziphus spina-christi L.) is a traditional herbaceous medicinal plant. In addition to its good flavor, sidr has antidiabetic, anti-inflammatory, sedative, analgesic, and hypoglycemic activities. Camel milk has a high nutritional and health value, but its salty taste remains the main drawback in relation to its organoleptic properties. The production of flavored or fortified camel milk products to mask the salty taste can be very beneficial. This study aimed to investigate the effects of sidr fruit pulp (SFP) on the functional and nutritional properties of fermented camel milk. SFP was added to camel milk at rates of 5%, 10%, and 15%, followed by the selection of the best-fermented product in terms of functional and nutritional properties (camel milk supplemented with 15% SFP), and an evaluation of its hypoglycemic activity in streptozotocin (STZ)-induced diabetic rats. Thirty-two male adult albino rats (weighing 150–185 g) were divided into four groups: Group 1, nontreated nondiabetic rats (negative control); Group 2, diabetic rats given STZ (60 mg/kg body weight; positive control); Group 3, diabetic rats fed a basal diet with fermented camel milk (10 g/day); and Group 4, diabetic rats fed a basal diet with fermented camel milk supplemented with 15% SFP (10 g/day). The results revealed that supplementation of camel milk with SFP increased its total solids, protein, ash, fiber, viscosity, phenolic content, and antioxidant activity, which was proportional to the supplementation ratio. Fermented camel milk supplemented with 15% SFP had the highest scores for sensory properties compared to other treatments. Fermented camel milk supplemented with 15% SFP showed significantly decreased (p < 0.05) blood glucose, malondialdehyde, low-density lipoprotein-cholesterol, cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, creatinine, and urea, and a significantly increased (p < 0.05) high-density lipoprotein-cholesterol, total protein content, and albumin compared to diabetic rats. The administration of fermented camel milk supplemented with 15% SFP in diabetic rats restored a series of histopathological changes alonsgside an improvement in various enzyme and liver function tests compared to the untreated group, indicating that fermented camel milk supplemented with 15% SFP might play a preventive role in such patients.

Probiotic survival, biological functionality and untargeted metabolomics of the bioaccessible compounds in fermented camel and bovine milk after in vitro digestion

This study investigated probiotic survival and biological functionality of the bioaccessible fraction of fermented camel milk (FCM) and fermented bovine milk (FBM) after in vitro digestion. Furthermore, untargeted metabolomic analysis was performed to identify the bioaccessible compounds in FCM and FBM, which were produced using starter bacteria (SC), a potential probiotic (Pro) or a combination thereof (SC + Pro), followed by storage (21 d). Survival of Pro and SC + Pro bacteria in FCM was higher than in FBM throughout in vitro digestion. The antioxidant activities of the bioaccessible fractions differed slightly between culture types, whereas the antiproliferative activity of SC was highest, followed by SC + Pro. Antiproliferative activity of the bioaccessible fractions of FCM was greater than for FBM. Untargeted metabolomics of FCM demonstrated discrimination between cultures and from FBM. FCM produced with SC + Pro and Pro had closer clustering than with SC. The bioaccessible fraction of FCM exhibited higher biological functionality compared to FBM.

Recent Advances in Camel Milk Processing

Simple Summary

The camel milk market was limited for a long time by its almost exclusive self-consumption use in nomadic camps. Significant development has been observed for the past two or three decades, including internationally, boosted by its reputation regarding its health effects for regular consumers. Such emergence has led the stakeholders in the sector to offer diversified products corresponding to the tastes of increasingly urbanized consumers, more sensitive to “modern” products. Thus, traditionally drunk in raw or naturally fermented form, camel milk has undergone unprecedented transformations such as pasteurization, directed fermentation, cheese or yoghurt processing, and manufacture of milk powder for the export market. However, the specific characteristics of this milk (composition, physical properties) mean that the technologies applied (copied from technologies used for cow milk) must be adapted. In this review, some technological innovations are presented, enabling stakeholders of the camel milk sector to satisfy the demand of manufacturers and consumers.

Abstract

Camel milk is a newcomer to domestic markets and especially to the international milk market. This recent emergence has been accompanied by a diversification of processed products, based on the technologies developed for milk from other dairy species. However, technical innovations had to be adapted to a product with specific behavior and composition. The transformation of camel milk into pasteurized milk, fermented milk, cheese, powder, or other products was supported, under the pressure of commercial development, by technological innovations made possible by a basic and applied research set. Some of these innovations regarding one of the less studied milk sources are presented here, as well as their limitations. Technical investigations for an optimal pasteurization, development of controlled fermentation at industrial scale, control of cheese technology suitable for standardized production, and improvements in processes for the supply of a high-quality milk powder are among the challenges of research regarding camel milk.