The physiological and rheological effects of foods supplemented with guar gum

Recent updates on guar gum derivatives in colon specific drug delivery

Colon specific delivery of therapeutics have gained much attention of pharmaceutical researchers in the recent past. Colonic specific targeting of drugs is used not only for facilitating absorption of protein or peptide drugs, but also localization of therapeutic agents in colon to treat several colonic disorders. Among various biopolymers, guar gum (GG) exhibits pH dependent swelling, which allows colon specific release of drug. GG also shows microbial degradation in the colonic environment which makes it a suitable excipient for developing colon specific drug delivery systems. The uncontrolled swelling and hydration of GG can be controlled by structural modification or by grafting with another polymeric moiety. Several graft copolymerized guar gum derivatives are investigated for colon targeting of drugs. The efficacy of various guar gum derivatives are evaluated for colon specific delivery of drugs. The reviewed literature evidenced the potentiality of guar gum in localizing drugs in the colonic environment. This review focuses on the synthesis of several guar gum derivatives and their application in developing various colon specific drug delivery systems including matrix tablets, coated formulations, nano or microparticulate delivery systems and hydrogels.

Plant-based hydrocolloids for efficient clarification of cane juices: rheological analysis and solidification studies

The present study is designed to study the efficiency of plant-based hydrocolloids for the efficient clarification of sugarcane juice and subsequent production of non-centrifugal sugars (NCSs). NCSs are generally produced with lime or other inorganic solids as a clarification agent, often leading to products with a bland taste and dark color. This work is a first of its kind, where plant-based hydrocolloids such as starch, xanthan gum, and guar gum are used for clarification studies. Clarification efficiency was evaluated in terms of separation efficiency, turbidity removal, sucrose content, color transmittance, and rheology studies. Preliminary studies revealed that starch showed a better separation efficiency of 78% compared to other hydrocolloids, and further rheology studies of starch-clarified juice showed a favourable shear-thickening (dilatant, n = 1.382) behaviour, whereas the other two hydrocolloids showed an unfavourable shear-thinning (pseudo plastic, n < 0.9) behaviour. Eventually, starch was found to be a better clarification agent and is proposed as an alternative to lime-based clarification. Solidification studies were performed with starch at various concentrations (0.02-0.04%), pH (6.8-7.2), and temperature (80 °C-100 °C), and it was found that NCSs produced via starch clarification showed superior properties compared with traditional lime-based clarification processes.

Application of guar (Cyamopsis tetragonoloba L.) gum in food technologies: A review of properties and mechanisms of action

With the world continuing to push toward modernization and the consumption of processed foods growing at an exponential rate, the demand for texturizing agents and natural additives has also risen as a result. It has become increasingly common to use thickening agents in food products to modify their rheological and textural properties and enhance their quality characteristics. They can be divided into (1) animal derived (chitosan and isinglass), (2) fermentation produced (xanthan and curdlan), (3) plant fragments (pectin and cellulose), (4) seaweed extracts (agar and alginate), and (5) seed flours (guar gum and locust bean gum). The primary functions of these materials are to improve moisture binding capacity, modify structural properties, and alter flow behavior. In addition, some have another responsibility in the food sector, such as the main ingredient in the delivery systems (encapsulation) and nanocomposites. A galactomannan polysaccharide extracted from guar beans (Cyamopsis tetragonolobus), known as guar gum (GG), is one of them, which has a wide range of utilities and possesses popularity among scientists and consumers. In the world of modernization, GG has found its way into numerous industries for use in food, cosmetics, pharmaceuticals, textiles, and explosives. Due to its ability to form hydrogen bonds with water molecules, it imparts significant thickening, gelling, and binding properties to the solution as well as increases its viscosity. Therefore, this study is aimed to investigate the characteristics, mechanisms, and applications of GG in different food technologies.

Changes in structure and physicochemical properties of Sophora japonica f. pendula galactomannan in late growth stage

Galactomannan (GM) has been widely applied in food and other fields due to its appealing physicochemical properties. In this work, considering the changes in structural and physicochemical properties of Sophora japonica f. pendula (SJ-GM) with very high mannose to galactose (M/G) ratio in the late deposition stage, extensive exploration is conducted. The core of structural change is the change of M/G ratio (4.94-5.68), which is caused by the loss of galactose side residues modulated by α-d-galactosidase during seed maturation. Afterwards, the more compact conformation, the higher molecular weight, the increased hydrophobicity, and the greater solution viscosity of SJ-GM can be caused. Notably, the gel strength of SJ-GM with the highest M/G surpasses other GMs, including fenugreek gum (M/G = 1.20), guar gum (M/G = 1.80), Gleditsia microphylla gum (M/G = 2.77), and LBG (M/G = 4.00). Finally, SJ-GM is proven to be an attractive alternative to other GMs.

The Effects of Soluble Dietary Fibers on Glycemic Response: An Overview and Futures Perspectives

The properties of each food, composition, and structure affect the digestion and absorption of nutrients. Dietary fiber (DF), especially viscous DF, can contribute to a reduction in the glycemic response resulting from the consumption of carbohydrate-rich foods. Target and control of postprandial glycemic values are critical for diabetes prevention and management. Some mechanisms have been described for soluble DF action, from the increase in chyme viscosity to the production of short-chain fatty acids resulting from fermentation, which stimulates gastrointestinal motility and the release of GLP-1 and PYY hormones. The postprandial glycemic response due to inulin and resistant starch ingestion is well established. However, other soluble dietary fibers (SDF) can also contribute to glycemic control, such as gums, β-glucan, psyllium, arabinoxylan, soluble corn fiber, resistant maltodextrin, glucomannan, and edible fungi, which can be added alone or together in different products, such as bread, beverages, soups, biscuits, and others. However, there are technological challenges to be overcome, despite the benefits provided by the SDF, as it is necessary to consider the palatability and maintenance of their proprieties during production processes. Studies that evaluate the effect of full meals with enriched SDF on postprandial glycemic responses should be encouraged, as this would contribute to the recommendation of viable dietary options and sustainable health goals.

Development of new eggplant spread product: A rheological and chemical characterization

Eggplant (Solanum melongena) is an important vegetable of the Nightshade family with high demand due to its nutritional value and medicinal properties. The principal objective of this work was to develop and standardize a spread eggplant paste (SEP) with the addition of guar gum and evaluate its physicochemical, bromatological, sensory, and rheological characteristics. A two-factor factorial design with three levels was used for the formulation, evaluating the percentage of guar gum and oil. Flow curves in steady-state and small-amplitude oscillatory shear tests were performed to evaluate the rheological properties of the pastes. Sensorial analysis was performed using descriptive analysis. The standardized eggplant showed no signs of phase separation being stable during storage. Samples presented a non-Newtonian shear-thinning behavior described by Ostwald de-Waele model (R² > 0.969). The products exhibit more elastic than viscous behavior, with a higher storage modulus than loss modulus in the evaluated frequency range, where the modules could be well described by a power function of the oscillatory frequency. The sensory evaluation revealed that the product color, odor, taste, and spreadability were acceptable, being an alternative for the transformation and agro-industrial use of eggplant for production chain development.

Storage Behavior of “Seddik” Mango Fruit Coated with CMC and Guar Gum-Based Silver Nanoparticles

Mango fruit (cv. Seddik) is known as a delicate fruit for storage after harvest. Herein, carboxymethyl cellulose (CMC) and guar gum-based silver nanoparticles (AgNPs) were used as fruit coatings, and their effects on postharvest storage behavior and quality attributes were investigated. AgNPs were synthesized using a chemical reduction approach and then combined with CMC and guar gum as coating bases. Mango fruits were coated with the developed and pre-characterized CMC-AgNPs and guar gum-AgNPs, and then packed and stored at 13 °C for 4 weeks. The results showed an increase in weight loss, respiration rate, total soluble solids (TSS), total sugars, and total carotenoids over the storage period. However, this increase was comparatively less significant in coated fruits compared to uncoated fruits. Firmness and titratable acidity (TA) significantly decreased during storage, but this decrease was less in coated fruits. Silver traces in fruit pulp samples were not detected. These findings showed the efficacy of CMC-AgNP and guar gum-AgNP coatings in delaying mango fruit ripening and maintaining fruit quality during cold storage. Therefore, these coatings could be promising alternative materials for extending the postharvest life and marketing period of mango fruit.

The influence of Konjac glucomannan on the functional and structural properties of wheat starch

The aim of this study was to characterize the influence of Konjac glucomannan (KGM) on the functional and structural properties of wheat starch. Results showed that KGM significantly decreased the starch hydrolysis rate, with a lower level of rapidly digestible starch (RDS), and a higher content of slowly digestible starch (SDS). Besides, KGM decreased the content of leached amylose, while enhanced the swelling power, water-holding capacity, freeze-thaw stability, and paste clarity of wheat starch, which indicated a good improvement on the functional properties. Differential scanning calorimetry (DSC) and X-ray diffraction patterns (XRD) manifested that the addition of KGM disrupted the original crystalline structures of wheat starch, which may result in the increased hydrolysis rate of starch. Interestingly, this did not consist with the decreased starch hydrolysis rate showed in the study. Moreover, FTIR results showed the existence of the interaction between KGM and starch. The morphological characterization demonstrated that the addition of KGM contributed to a more compact structure of freeze-dried wheat starch. And KGM inhibited the expansion of starch granules and formed a barrier around the gelatinized starch. Therefore, the barrier around the starch granules and the interaction between KGM and starch were considered to be the important reasons that affected the starch digestibility.

Mannans: An overview of properties and application in food products

This review aims to emphasize the occurrence and abundant presence of mannans in nature, their classification, structural differences and significance in food and feed industry. With rising demand from the consumers' end for novel natural foods, usage of galactomannan and glucomannan has also increased alternatively. Non toxicity of mannans permits their usage in the pharmaceutical, biomedical, cosmetics, and textile industries. In the food industry, mannans have various applications such as edible films/coating, gel formation, stiffeners, viscosity modifiers, stabilizers, texture improvers, water absorbants, as prebiotics in dairy products and bakery, seasonings, diet foods, coffee whiteners etc. Applications and functions of these commonly used commercially available mannans have therefore, been highlighted. Mannans improve the texture and appeal of food products and provide numerous health benefits like controlling obesity and body weight control, prebiotic benefits, constipation alleviaton, prevent occurrence of diarrhea, check inflammation due to gut related diseases, management of diverticular disease management, balance intestinal microbiota, immune system modulator, reduced risk of colorectal cancer etc. Mannan degrading enzymes are the key enzymes involved in degradation and are useful in various industrial processes such as fruit juice clarification, viscosity reduction of coffee extracts etc. besides facilitating the process steps and improving process quality.

Guar Gum as an Edible Coating for Enhancing Shelf-Life and Improving Postharvest Quality of Roma Tomato (Solanum lycopersicum L.)

There exists an increasing interest from consumers and scientific community in developing edible-natural-biodegradable coatings to replace commercial wax-based coatings for maintaining postharvest quality of vegetables. In this work, the effectiveness of guar gum coating on various quality characteristics of Roma tomato at 22±2°C over a 20 d storage period was investigated. Tomatoes were covered with a 1.5% guar gum coating plasticized with glycerol at 30% and stored at 22±2°C and 40% RH for 20-d. Tomatoes covered with edible coating significantly enhanced firmness and reduced weight loss, delayed changes on soluble-solids-content, retarded loss of total acidity, and decreased respiration rate compared with uncoated-control fruit. Sensory analysis by trained panelists revealed that the use of the edible coating influenced the acceptability of tomatoes. There were significant differences on the scores given by panelists when comparing the coated and uncoated tomatoes. It was concluded that guar gum affected favorably the physicochemical, microbial, and sensorial quality properties of Roma tomato and therefore could be beneficial in delaying the ripening process at 22±2°C.

Application of guar-xanthan gum mixture as a partial fat replacer in meat emulsions

The physicochemical, oxidative, texture and microstructure properties were evaluated for low fat meat emulsions containing varying levels of guar/xanthan gum mixture (1:1 ratio) as a fat substitute. Partial replacement of fat with guar/xanthan gum resulted in higher emulsion stability and cooking yield but lower penetration force. Proximate composition revealed that high fat control had significantly higher fat and lower moisture content due to the difference in basic formulation. Colour evaluation revealed that low fat formulations containing gum mixture had significantly lower lightness and higher yellowness values than high fat control formulation. However non-significant difference was observed in redness values between low fat formulations and the high fat control. The pH values of the low fat formulations containing gum mixture were lower than the control formulations (T0 and TC). The MetMb% of the high fat emulsion formulation was higher than low fat formulations. The significant increase of TBARS value, protein carbonyl groups and loss of protein sulphydryl groups in high fat formulation reflect the more oxidative degradation of lipids and muscle proteins during the preparation of meat emulsion than low fat formulations. The SEM showed a porous matrix in the treatments containing gum mixture. Thus, the guar/xanthan gum mixture improved the physicochemical and oxidative quality of low fat meat emulsions than the control formulations.

Sonication-based improvement of the physicochemical properties of Guar Gum as a potential substrate for modified drug delivery systems

Guar Gum is a natural polysaccharide that, due to its physicochemical properties, is extensively investigated for biomedical applications as a matrix for modified drug delivery, but it is also used in the food industry as well as in cosmetics. A commercial sample of Guar Gum was sonicated for different periods of time, and the reduction in the average molecular weight was monitored by means of viscometric measurements. At the same time, the rheological behaviour was also followed, in terms of viscoelasticity range, flow curves, and mechanical spectra. Sonicated samples were used for the preparation of gels in the presence of borate ions. The effect of borax on the new samples was investigated by recording mechanical spectra, flow curves, and visible absorption spectra of complexes with Congo Red. The anisotropic elongation, observed in previous studies with tablets of Guar Gum and borax, was remarkably reduced when the sonicated samples were used for the preparation of the gels.

Food-based ingredients to modulate blood glucose

Maintenance of normal blood glucose levels is important for avoiding chronic diseases such as type 2 diabetes, cardiovascular problems, and obesity. Type 2 diabetes is one of the major health problems affecting the world population and this condition can be exacerbated by poor diet, low physical activity, and genetic abnormalities. Food plays an important role in the management of blood glucose and associated complications in diabetes. This is attributed to the ability of food-based ingredients to modulate blood glucose without causing any adverse health consequences. This chapter focuses on four important food groups such as cereals, legumes, fruits, and spices that have active ingredients such as soluble dietary fiber, polyphenols, and antinutrients with the ability to reduce glycemic and insulin response in humans. Other food ingredients such as simple sugars, sugar alcohols, and some proteins are also discussed in moderation.