Nutritional and Microbiological Quality of Tiger Nut Tubers (Cyperus esculentus), Derived Plant-Based and Lactic Fermented Beverages

A review on the biological and bioactive components of Cyperus esculentus L.: insight on food, health and nutrition

Tiger nut (Cyperus esculentus L.) is a small, tuberous root vegetable that has gained increasing attention in recent years due to its potential health benefits. This review article provides an elaborate overview of tiger nut, including its botany, historical uses, nutritional composition, potential health benefits and traditional medicinal uses. This review article comprehensively discusses the nutritional profile of tiger nut, providing a detailed understanding of its nutrient content. Furthermore, the potential health benefits of tiger nut are thoroughly reviewed, including its effects on digestive health, cardiovascular health, blood sugar control, immune function and other potential therapeutic uses. Scientific articles used for this review were retrieved from ScienceDirect, Google Scholar, PubMed and SciELO databases. Only articles published between 1997 and 2022 were used for research. This review contributes to a better understanding of tiger nut and its prospective uses in functional foods and medicine by combining the available scientific material. © 2024 Society of Chemical Industry.

Microbial exopolysaccharides in the biomedical and pharmaceutical industries

The most significant and renewable class of polymeric materials are extracellular exopolysaccharides (EPSs) produced by microorganisms. Because of their diverse chemical and structural makeup, EPSs play a variety of functions in a variety of industries, including the agricultural industry, dairy industry, biofilms, cosmetics, and others, demonstrating their biotechnological significance. EPSs are typically utilized in high-value applications, and current research has focused heavily on them because of their biocompatibility, biodegradability, and compatibility with both people and the environment. Due to their high production costs, only a few microbial EPSs have been commercially successful. The emergence of financial barriers and the growing significance of microbial EPSs in industrial and medical biotechnology has increased interest in exopolysaccharides. Since exopolysaccharides can be altered in a variety of ways, their use is expected to increase across a wide range of industries in the coming years. This review introduces some significant EPSs and their composites while concentrating on their biomedical uses.

Biosynthesis of exopolysaccharide from waste molasses using Pantoea sp. BCCS 001 GH: a kinetic and optimization study

The bacterium Pantoea sp. BCCS 001 GH produces an exopolysaccharide (EPS) named Pantoan through using sugar beet molasses (SBM) as an inexpensive and widely available carbon source. This study aims to investigate the kinetics and optimization of the Pantoan biosynthesis using Pantoea sp. BCCS 001 GH in submerged culture. During kinetics studies, the logistic model and Luedeking–Piret equation are precisely fit with the obtained experimental data. The response surface methodology (RSM)-central composite design (CCD) method is applied to evaluate the effects of four factors (SBM, peptone, Na₂HPO₄, and Triton X-100) on the concentration of Pantoan in batch culture of Pantoea sp. BCCS 001 GH. The experimental and predicted maximum Pantoan production yields are found 9.9 ± 0.5 and 10.30 g/L, respectively, and the best prediction factor concentrations are achieved at 31.5 g/L SBM, 2.73 g/L peptone, 3 g/L Na₂HPO_4, and 0.32 g/L Triton X-100 after 48 h of submerged culture fermentation, at 30 °C. The functional groups and major monosaccharides (glucose and galactose) of a purified Pantoan are described and confirmed by ¹HNMR and FTIR. The produced Pantoan is also characterized by thermogravimetric analysis and the rheological properties of the biopolymer are investigated. The present work guides the design and optimization of the Pantoea sp. BCCS 001 GH culture media, to be fine-tuned and applied to invaluable EPS, which can be applicable in food and biotechnology applications.

Multimycotoxin Analysis in Oat, Rice, Almond and Soy Beverages by Liquid Chromatography-Tandem Mass Spectrometry

This study developed and validated an analytical methodology for the determination of aflatoxins, enniatins, beauvericin, zearalenone, ochratoxin-A, alternariols, HT-2 and T-2 toxin in soy, oat, rice and almond beverages, based on solid phase extraction columns (SPE) and analyzed by liquid chromatography coupled to mass spectrometry in tandem. C18 SPE was successfully applied, obtaining recoveries that range from 72 ± 12% (ochratoxin-A) to 99 ± 4% (ENA1) at high level (L1) and 65 ± 8% (T-2) to 128 ± 9% (alternariol monomethyl ether) at low levels (L3). The methodology was validated according to Commission Decision 2002/657/EC, with limits of quantification ranging from 0.3 (AFs in oat beverages) to 18 ng/mL (HT-2 in rice beverage). The analysis of 56 beverage samples purchased from Valencia (Spain) showed at least one mycotoxin occurring in 95% of samples, including carcinogenic aflatoxins, and oat beverage was the most contaminated. This is a newest validated methodology for the quantification of sixty mycotoxins in oat, rice, almond and soy beverages.

Tiger nut (Cyperus esculentus): Nutrient profiling using HPLC and UV-spectroscopic techniques

Food insecurity and undernourishment constitute a major challenge in Africa and the world at large. To meet key nutritional targets and tackle the menace of undernourishment, we need to exploit available but underutilised food crops. A common underutilised food crop with the potential to improve daily nutrition is tiger nut. This potential is evidenced in the number of essential amino acids detected, which constitute 74.425% of the entire amino acids detected, in addition to important minerals and vitamins. The nutritional composition of the yellow variety of tiger nut (Cyperus esculentus) was determined using the standard methods of high-performance liquid chromatography and UV-spectroscopy. Ten amino acids were identified and quantified, including six essential amino acids, of which valine had the highest concentration (67.59 μg/100 g), followed by leucine (3.019 μg/100 g), phenylalanine (1.767 μg/100 g), lysine (0.946 μg/100 g), histidine (1.048 μg/100 g) and tryptophan (0.055 μg/100 g). The other amino acids were proline (24.124 μg/100 g), cysteine (1.269 μg/100 g), glycine (0.024 μg/100 g), and glutamine (0.022 μg/100 g). Monosaccharides detected were ribose (41.76%), glucose (21.52%), sedoheptulose (17.94%), fructose (4.566%), rhamnose (1.78%) and mannose (1.58%), whilst disaccharides detected were sucrose (87.66%) and maltose (11.39%). Mineral concentrations were K 144.80 ± 1.10 mg/100 g, Ca 94.39 ± 0.02 mg/100 g, Na 83.92 ± 0.04 mg/100 g, Fe 19.36 ± 0.54 mg/100 g, Mg 17.63±0.13 mg/100 g, Cu 13.28±0.05 mg/100 g and Zn 5.18±0.01 mg/100 g Vitamins A, B2, C and E were detected and quantified as 53.93±1.03, 7.61±1.20, 31.70±1.25 and 128.75±0.74 μg/100 g, respectively. The chemical and nutritional properties of the yellow variety of tiger nut suggest that it is rich in essential amino acids, minerals, and some vitamins. Hence, it should be recommended to persons with nutritional deficiencies as it is cheap and available all year round.

Ingredients, Processing, and Fermentation: Addressing the Organoleptic Boundaries of Plant-Based Dairy Analogues

Consumer interest and research in plant-based dairy analogues has been growing in recent years because of increasingly negative implications of animal-derived products on human health, animal wellbeing, and the environment. However, plant-based dairy analogues face many challenges in mimicking the organoleptic properties of dairy products due to their undesirable off-flavours and textures. This article thus reviews fermentation as a viable pathway to developing clean-label plant-based dairy analogues with satisfactory consumer acceptability. Discussions on complementary strategies such as raw material selection and extraction technologies are also included. An overview of plant raw materials with the potential to be applied in dairy analogues is first discussed, followed by a review of the processing steps and innovative techniques required to transform these plant raw materials into functional ingredients such as plant-based aqueous extracts or flours for subsequent fermentation. Finally, the various fermentation (bacterial, yeast, and fungal) methodologies applied for the improvement of texture and other sensory qualities of plant-based dairy analogues are covered. Concerted research efforts would be required in the future to tailor and optimise the presented wide diversity of options to produce plant-based fermented dairy analogues that are both delicious and nutritionally adequate.

Histomorphometric and biochemical activities of bioactive component of Cyperus esculentus tubers extract on letrozole-induced polycystic ovarian syndrome and cholesterol homeostasis in female Sprague-Dawley rats

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine and metabolic disorder, causes irregular menstrual cycles, dyslipidemia, excessive body weight, oxidative stress, hyperandrogenism, and infertility. This study focused on the impact of Cyperus esculentus (CES) on letrozole-induced PCOS in female Sprague-Dawley rats. Twenty (20) normal rats and twenty (20) PCOS rats (150–200 g, 8 weeks old) were randomly divided into four groups of ten ( n = 10) rats each. Group A served as normal control group received 2 mL of normal saline, group B treated with 500 mg/kg body weight of CES , group C PCOS control group received 2 mL of normal saline, and group D PCOS rats post-treated with 500 mg/kg body weight of CES daily through gastric gavage for 30 days. Estrus cyclicity, body and ovaries weights, biochemical and histological parameters were measured. Observed irregular estrus cyclicity and multiple cysts in PCOS rats, increase glycemia, ovarian weight, triglycerides, total cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, malondialdehyde, luteinizing hormone (LH), testosterone, and decrease high-density lipoprotein cholesterol, estradiol, progesterone, catalase, reduced glutathione (GSH), and superoxide dismutase levels, compared with control. The intervention of CES ameliorated and restored the estrus cyclicity reproductive hormone, biochemical, and structural alterations. Moreover, CES significantly decreased cystic follicles, LH, and testosterone levels, but increased estradiol concentration. This plant may be beneficial in the management and treatment of PCOS-related reproductive and metabolic disorders.

Microbial Exopolysaccharides in Traditional Mexican Fermented Beverages

Exopolysaccharides (EPS) are biopolymers produced by many microorganisms, including some species of the genus Acetobacter, Bacillus, Fructobacillus, Leuconostoc, Lactobacillus, Lactiplantibacillus, Pediococcus, Pichia, Rhodotorula, Saccharomycodes, Schizosaccharomyces, and Sphingomonas, which have been reported in the microbiota of traditional fermented beverages. Dextran, levan, glucan, gellan, and cellulose, among others, are EPS produced by these genera. Extracellular biopolymers are responsible for contributing to specific characteristics to fermented products, such as modifying their organoleptic properties or contributing to biological activities. However, EPS can be easily found in the dairy industry, where they affect rheological properties in products such as yogurt or cheese, among others. Over the years, LAB has been recognized as good starter strains in spontaneous fermentation, as they can contribute beneficial properties to the final product in conjunction with yeasts. To the best our knowledge, several articles have reported that the EPS produced by LAB and yeasts possess many both biological and technological properties that can be influenced by many factors in which fermentation occurs. Therefore, this review presents traditional Mexican fermented beverages (tavern, tuba, sotol, and aguamiel) and relates them to the microbial EPS, which affect biological and techno-functional activities.

Obtaining Antioxidants and Natural Preservatives from Food By-Products through Fermentation: A Review

Industrial food waste has potential for generating income from high-added-value compounds through fermentation. Solid-state fermentation is promising to obtain a high yield of bioactive compounds while requiring less water for the microorganism’s growth. A number of scientific studies evinced an increase in flavonoids or phenolics from fruit or vegetable waste and bioactive peptides from cereal processing residues and whey, a major waste of the dairy industry. Livestock, fish, or shellfish processing by-products (skin, viscera, fish scales, seabass colon, shrimp waste) also has the possibility of generating antioxidant peptides, hydrolysates, or compounds through fermentation. These bioactive compounds (phenolics, flavonoids, or antioxidant peptides) resulting from bacterial or fungal fermentation are also capable of inhibiting the growth of commonly occurring food spoilage fungi and can be used as natural preservatives. Despite the significant release or enhancement of antioxidant compounds through by-products fermentation, the surface areas of large-scale bioreactors and flow patterns act as constraints in designing a scale-up process for improved efficiency. An in-process purification method can also be the most significant contributing factor for raising the overall cost. Therefore, future research in modelling scale-up design can contribute towards mitigating the discard of high-added-value generating residues. Therefore, in this review, the current knowledge on the use of fermentation to obtain bioactive compounds from food by-products, emphasizing their use as natural preservatives, was evaluated.

Development of Probiotic Almond Beverage Using Lacticaseibacillus rhamnosus GR-1 Fortified with Short-Chain and Long-Chain Inulin Fibre

Plant-based beverages are growing in popularity due to the rise of vegetarianism and other health trends. A probiotic almond beverage that combines the properties of almonds, inulin, and Lacticaseibacillusrhamnosus GR-1 may meet the demand for a non-dairy health-promoting food. The purpose of this study was to investigate the viability of L. rhamnosus GR-1 and pH in five fermented almond beverage samples, supplemented with either 2% or 5% (w/v) short-chain or long-chain inulin over 9 h of fermentation and 30 days of refrigerated storage. All almond beverage samples achieved a mean viable count of at least 107 CFU/mL during 9h of fermentation and 30 days of refrigerated storage. The probiotic almond beverage supplemented with 2% (w/v) short-chain inulin had a significantly higher mean microbial count (p = 0.048) and lower pH (p < 0.001) throughout fermentation, while the control and the long-chain inulin treatments had the lowest viable counts and acidity, respectively. This study shows that the addition of short-chain and long-chain inulin had no adverse effects on the viability of L. rhamnosus GR-1. Therefore, the probiotic almond beverage has the potential to be a valid alternative to dairy-based probiotic products.

Sensory Acceptability and Proximate Composition of 3-Blend Plant-Based Dairy Alternatives

Limitations of plant-based dairy alternatives as sustainable foods are their relatively low protein content and low sensory appeal. In this study, we used a consumer-led product development approach to improve the sensory appeal of existing prototypes of 3-blend dairy alternatives produced from melon seeds, peanuts and coconut. We used Relative Preference Mapping (RPM) and consumer acceptance testing using the 9-point hedonic scale to respectively identify innovative flavours and deduce the effect of ingredient components on consumer sensory appeal. Mixture design was used as the formulation tool to obtain optimized prototypes of the 3-blend dairy alternatives. Proximate analysis of the new prototypes, instrumental color assessment and consumer testing provided a basis to select a sustainable 3-blend dairy alternative. This prototype had a relatively high protein content (2.16%), was considered innovative by target consumers and also had a moderate liking score (6.55 ± 1.88) on the 9-point hedonic scale. Prototypes with higher protein content had low sensory appeal and were not considered innovative. Other prototypes with innovative sensory appeal had low protein content. By combining different plant raw materials and utilizing different sensory testing methods, we were able to design sustainable plant-based dairy alternatives which can be further optimized.

Berrios J. Tiger Nut (Cyperus esculentus) as a Functional Ingredient in Gluten-Free Extruded Snacks

Tiger nut (TN) is a nutritious source of gluten-free flour, used generally in healthy beverages, but its incorporation in gluten-free extruded snacks has not been explored. TN flour was blended at different concentrations (up to 70%) with rice flour and soluble fiber, for the development of gluten-free snacks on a twin-screw extruder. The effect of TN inclusion in the formulations was evaluated on relevant physiochemical characteristics of the snacks. Viscoamylograph of the raw formulations showed that TN addition increased (p < 0.01) onset temperature and delayed peak viscosity. In the extruded flours, TN contributed to limit the starch degradation during extrusion. Diameter, expansion ratio, true density, and total pore volume of the extrudates were reduced (pf < 0.01) by the increased TN content in the formulations, while bulk density rose. The surfaces of the extruded snacks were modified by the increasing inclusion of TN in substitution of rice in the formulations. Extrudates containing 10% TN showed the best overall texture profile. Moreover, TN addition enhanced the ash and protein content of the snacks and increased their total antioxidant activity. This study demonstrated that incorporation of 10% TN flour into rice-based formulation was suitable for making gluten-free snacks with acceptable physical properties.

Traditional and Artisanal Beverages in Nigeria: Microbial Diversity and Safety Issues

A review of up to 90 articles on the microorganisms associated with important artisanal or traditional beverages in Nigeria was carried out. This resulted in an overview of the prevalent microorganisms associated with soymilk, nono (fermented cow milk), tiger nut milk, yoghurt, kunu, zobo, palm wine and the local beers pito and brukutu. The bacteria genera, namely Bacillus, Escherichia, Lactobacillus, Staphylococcus, and Streptococcus, were detected in all nine beverages. On the contrary, this survey resulted in finding that the genera Saccharomyces, Aspergillus, Candida, and Penicillium were the eukaryotic microorganisms isolated in all beverages. The occurrence of fungal isolates, which can be responsible for producing mycotoxins, is a concern and shows the need for post-production tests. Overall, there is a low prevalence of bacteria associated with hygiene, especially the Escherichia genus in alcoholic beverages such as palm wine, pito and burukutu, which may be due both to a low acidity and high ethanol content. However, the prevalence of hygiene indicator genera was higher in nonalcoholic drinks, probably because of incorrect practices during processing. The magnitude of the production and sales of unregulated local beverages in Nigeria has reached the stage where significant regulation and food safety standards are required to safeguard public health. An opportunity exists to monitor and characterize the microbial flora of the artisanal beverages using molecular methods at all stages of production and storage.

Mycotoxins in Functional Beverages: A Review

Consumer dietary habits have drastically changed in recent decades and functional beverages now have a strong position in the market. The majority of these beverages are produced using simple processes that use raw products, such as cereals, legumes, fruits, and nuts, among others, and these are known to be frequently contaminated with mycotoxins. This review is focused on the occurrence of these toxic compounds in plant-based milks, fruit juices, and herbal teas. The fate of the toxins during processing is discussed to establish the potential risk posed by the consumption of these kind of beverages regarding mycotoxin uptake.

Ready to Use Therapeutical Beverages: Focus on Functional Beverages Containing Probiotics, Prebiotics and Synbiotics

The growing global interest in functional foods containing nutrients capable of adding possible beneficial health effects is rapidly increasing both interest and consumer demand. In particular, functionalized beverages for their potential positive effect on health e.g., decreasing cholesterol level, lowering sugar, high fiber content, ability to enhance the immune system, and help digestion, have recently received special attention. Among the different beverages available on the market, probiotic dairy and non-dairy products have attracted much attention because of their affordable cost and their numerous therapeutic activities. Fermented milk and yogurt are currently worth €46 billion, with 77% of the market reported in Europe, North America, and Asia. Consumption of dairy beverages has some limitations due for example to lactose intolerance and allergy to milk proteins, thereby leading consumers to use non-dairy beverages such as fruit, grains, and vegetable juices to add probiotics to diet as well as driving the manufacturers to food matrices-based beverages containing probiotic cultures. The purpose of this review article is to evaluate the therapeutic performance and properties of dairy and non-dairy beverages in terms of probiotic, prebiotic, and synbiotic activities.

Use of Tiger Nut (Cyperus esculentus L.) Oil Emulsion as Animal Fat Replacement in Beef Burgers

The present study evaluated the replacement of beef fat in beef burgers using a tiger nut (Cyperus esculentus L.) oil emulsion, in order to reduce total fat and saturated fatty acids in the studied samples. Three formulations were processed: Control—100% beef fat; tiger nut 50% (TN50)—50% of beef fat replaced using tiger nut oil emulsion and tiger nut 100% (TN100)—100% of beef fat replaced by tiger nut oil emulsion. The physicochemical parameters were affected after fat replacement. Moreover, the protein and fat contents decreased in those sample with tiger nut oil emulsion, thus the formulation TN100 can be considered as “reduced fat content”. Regarding color, an increased L* and b* value parameters was observed after TN100 while the values of a* remained similar to the Control samples. The hardness, cohesiveness, gumminess and chewiness were similar in all formulations. The addition of tiger nut oil emulsion as a substitute for beef fat reduced saturated fat and increased the mono- and polyunsaturated fatty acids. Oleic acid was found to be in highest proportions in burgers. The TN100 samples were considered as acceptable by consumers. Therefore, total replacement of beef fat using tiger nut oil emulsions in beef burger resulted in a well-accepted and healthier meat product with reduced total and saturated fat contents, as well as increased unsaturated fatty acids.

Enhanced Aromatic Profile and Functionality of Cheese Whey Beverages by Incorporation of Probiotic Cells Immobilized on Pistacia terebinthus Resin

: In the present study, cheese whey was utilized for the development of a novel functional beverage, using Lactobacillus casei ATCC 393 probiotic cells immobilized on Pistacia terebinthus resin (pissa Paphos). Evaluation of shelf life of the produced beverages showed that spoilage microorganisms were not observed in beverages containing P. terebinthus resin. Terpenes' rich content might have contributed to the antimicrobial activity of the produced beverages; however, no significant effect on the viability of the immobilized probiotic cells was obtained. Whey beverages containing the immobilized biocatalyst retained a high viability (>1 × 106 CFU/g) of probiotic cells during a storage period of 30 days at 4 °C. The superiority of whey beverages containing the immobilized biocatalyst was also highlighted by GC-MS analysis, while the enhanced aromatic profile, which was mostly attributed to the higher concentration of terpenes, was also detected during the sensory evaluation performed. Conclusively, this study indicated the high commercialization potential of these novel functional whey beverages, within the frame of a sustainable dairy waste valorization approach. To the best of our knowledge, this is the first food-oriented approach within the guidelines of the circular economy reported in the literature, using the autochthonous Pistacia terebinthus resin for the production of functional whey beverages.

Development, Characterization, and Bioactivity of Non-Dairy Kefir-Like Fermented Beverage Based on Flaxseed Oil Cake

Flaxseed oil cake (FOC) was evaluated as a potential substrate for the production of a novel kefir-like fermented beverage. Three variants containing 5%, 10%, and 15% (w/w) of FOC were inoculated with kefir grains and incubated at 25 °C for 24 h. After processing, beverages were stored in refrigerated conditions (6 °C) for 21 days. Changes in microbial population, pH, acidity, levels of proteins, polyphenolics, flavonoids, ascorbic acid, and reducing sugars were estimated. Additionally, viscosity, firmness, color, and antioxidant properties were determined. Results showed that lactic acid bacteria as well as yeast were capable of growing well in the FOC without any supplementation. During refrigerated storage, the viability of the microorganisms were over the recommended minimum level for kefir products. As a result of fermentation, the beverages showed excellent antioxidant activity. Because of the functional characteristics conferred to the FOC beverages, the use of kefir grains showed adequate potential for the industrial application. Therefore, this beverages could be used as a new, non-dairy vehicle for beneficial microflora consumption, especially by vegans and lactose-intolerant consumers.

Safety and Microbiological Quality

Food fermentation aims, primarily, to increase the shelf life of perishable foodstuffs [...]