Comparative studies of xanthan, guar and tragacanth gums on stability and rheological properties of fresh and stored ketchup

Evaluation of multicomplex systems on pomegranate concentrate loaded alginate hydrogels by low-field NMR relaxometry: physicochemical characterization and controlled release study

Alginate (ALG) and various gums are potential biomaterials to be employed in hydrogel designs for both food and biomedical applications. This study evaluated a multicomplex design by combining food grade polymers to examine their polymer-polymer interactions and design an oral delivery system for pomegranate concentrate (PC). ALG was replaced with gum tragacanth (GT), xanthan (XN) and their equal combinations (GT:XN) at 50% ratio in hydrogel fabrication. In addition to CaCI2 in binding solution, honey (H) and chitosan (CH) were also used during physical crosslinking. Relaxation time constants in NMR indicated poor ability of GT for water entrapment especially in the presence of honey (S2H). They also confirmed FTIR results indicating similar trends. Strong negative correlations were observed between T2 and texture results. GT replacement of ALG especially in the use of single CaCI2 (S2) promoted higher PC release up to 80% in digestive media compared to XN substitution (S3). This study promoted use of LF NMR as an indicator for polymer mixture characterization in complex gels. ALG based gels could be modified by replacing ALG with different kinds of gums and with use of different binding solutions to regulate target compound release in food and pharmaceutical fields.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05730-2.

Effect of partial substitution of tomato for avocado on physico-chemical and sensory aspects of sweet-and-sour sauce

This study aimed to develop sweet-and-sour sauces with partial substitution of tomato for avocado. Four sauces formulations containing 0%, 25%, 50%, and 75% avocado pulp were prepared. The pH, titratable acidity (TA), sugar: acid ratio, color, consistency, and syneresis analyses were performed. Sensory acceptance was measured by the hedonic, Just-about-right (JAR), and purchase intent scales. Besides, a check-all-that-apply (CATA) form was applied to obtain description data on the formulations. The results of the color parameters showed that treatments containing avocado had higher (p < 0.05) lightness and yellowness. The avocado addition improved the rheological measurements. There was an increase in the consistency of the sauces when the avocado concentration increased. The opposite was observed for syneresis, which decreased (p < 0.05) as the avocado pulp concentration increased. Sensory evaluation revealed good consumer acceptance, and purchase intent analysis showed that most consumers would buy this product. For JAR data, sauces with 50 and 75% avocado had highest values of consistency in the JAR region. The consumers who reported the formulation with 25% avocado to be "not enough" penalized its acceptance, reducing the overall acceptance. Based on the frequency of terms cited by consumers in the CATA, it was possible to consider specific terms for each formulation. The terms pleasant color, good taste, brightness, and good consistency were associated with high overall acceptance. These terms were mostly used for sauces with 25% and 50% avocado. Therefore, sweet-and-sour sauces based on a combination of tomato and avocado has proven to be a viable alternative to traditional ketchup.

Using the mixture design approach to predict the rheological properties of low-calorie dairy desserts containing gum tragacanth exuded by three Iranian Astragalus species

In this study, the flow behavior and creep parameters of saffron desserts containing gum tragacanth combinations of three species were modeled by the mixture design approach. Flow behavior and creep-recovery experiments were performed and models were predicted for apparent viscosity, consistency index, flow index, instantaneous compliance, and viscoelastic compliance. Five representative samples regarding the range of apparent viscosity at the shear rate of 50 s^-1 were subjected to sensory evaluation. According to rheological measurements, the addition of GT species of A. gossypinus led to the production of a dessert with a strong structure. Then, two samples with the highest consistency index and the lowest creep parameters were compared with two commercial saffron desserts. The results revealed that the overall acceptance of the two selected samples [containing 4% (w/w) A. gossypinus or 2.66% (w/w) A. gossypinus and 1.33% (w/w) A. fluccosus] was similar to those of the two commercial samples.

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.

Determination of relationship between sensory viscosity rating and instrumental flow behaviour of soluble dietary fibers

The shear-thinning low, medium and high-viscosity fiber preparations (0.15-1.05 % psyllium husk, 0.07-0.6 % guar gum, 0.15-1.20 % gum tragacanth, 0.1-0.8 % gum karaya, 0.15-1.05 % high-viscosity Carboxy Methyl Cellulose and 0.1-0.7 % xanthan gum) showed that the consistency coefficient (k) was a function of concentration, the relationship being exponential (R(2), 0.87-0.96; P < 0.01). The flow behaviour index (n) (except for gum karaya and CMC) was exponentially related to concentration (R(2), 0.61-0.98). The relationship between k and sensory viscosity rating (SVR) was essentially linear in nearly all cases. The SVR could be predicted from the consistency coefficient using the regression equations developed. Also, the relationship of k with fiber concentration would make it possible to identify the concentration of a particular gum required to have desired consistency in terms of SVR.