This work underlines that the role of water, its flow properties and its expulsion from the spatial network during oral processing, cannot be neglected in understanding the relation between gelled food structures and its sensory perception. It is shown that the properties of the included water phase of semi-solids are important as this phase can boost the water content in the oral cavity, and thereby increase taste sensations like sweetness. Moreover, the included water phase also plays a crucial role in how the energy exerted onto the gel during palating is used for either fracture, stored or dissipated in or by the network. To demonstrate this, a series of mixed whey protein/polysaccharide cold-set gels have prepared that were studied for a number of rheological and sensorial properties. Also, information on the expulsed serum volume during uniaxial compression and the breakdown pattern of these gels in the oral cavity was determined. It is shown that expulsion of serum from a gel during oral processing can be substantial and set by the morphology of the formed gel and the stiffness of the matrix. This expulsed serum volume is directly proportional to taste response. Moreover, it is found that both the viscous and elastic flow of serum through the gel upon deformation contribute to the perceived crumbliness of gels by lowering the recoverable energy. The elastic contribution of polysaccharides in the serum impairs with the energy available for fracture during oral processing, thereby affecting the sensory spreadability of the product.

Gels are viscoelastic systems built up with a liquid phase entrapped in a three-dimensional network, which can behave as carriers for bioactive food ingredients. Many attempts have been made to design gel structures in the water phase (hydrogels, emulsion gels, bigels) or oil phase (organogels, bigels) in order to improve their delivery performances. Hydrogels are originated from proteins or polysaccharides, which are suitable for the delivery of hydrophilic ingredients. Organogels are mainly built up with the self-assembling of gelator molecules in the oil phase, and they offer good carriers for lipophilic ingredients. Emulsion gels and bigels, containing both aqueous and oil domains, can provide accommodations for lipophilic and hydrophilic ingredients simultaneously. Gel structures (e.g. rheology, texture, water holding capacity, swelling ratio) can be modulated by choosing different gelators, modifying gelation techniques, and the involvement of other ingredients (e.g. oils, emulsifiers, minerals, acids), which then alter the diffusion and release of the bioactive ingredients incorporated. Various studies have proved that gel-based delivery systems are able to improve the stability and bioavailability of many bioactive food ingredients. This review provides a state-to-art overview of different gel-based delivery systems, highlighting the significance of structure–functionality relationship, to provide advanced knowledge for the design of novel functional foods.

The work is intended to explore the suitability of underutilized coconut water (a byproduct of food industry) for the production of exopolysaccharides (EPS) by Agrobacterium sp. CFR 24. Besides checking the suitability of coconut water for the production of water-soluble (WS) and water-insoluble (WIS) EPS, certain fermentation parameters, such as initial pH, incubation period and kinetics of EPS production were investigated. The coconut water medium was found to support the production of both types of EPS. The optimal initial pH and temperature was found to be 6·0 and 30°C, respectively. In shake flask (150 rev min[superscript [-]1]) studies, high-cell density inoculum resulted in the production of 11·50 g l[superscript [-]1] of WIS-EPS and 4·01 g l[superscript [-]1] WS-EPS after 72 and 96 h of fermentation, respectively. Coconut water was found suitable for the production of microbial EPS by Agrobacterium sp. CFR 24 strain. Under optimum conditions, it produced a good amount of WIS-EPS, which is comparable with that of the sucrose medium (11 g l[superscript [-]1]). This is the first report on the use of coconut water as a fermentation medium for the production of any microbial EPS. Besides producing value-added products, use of this food industry byproduct, which is often being drained out, can significantly reduce the problem of environmental pollution.

There has been a growing interest in developing effective strategies to inhibit lipid oxidation in emulsified food products by utilization of natural phenolic antioxidants owing to their growing popularity over the past decades. However, due to the complexity of emulsified systems, the inhibition mechanism of phenolic antioxidants against lipid oxidation is rather complicated and not yet fully understood. In order to highlight the importance of polarity of phenolic antioxidants in emulsified systems according to the polar paradox, this review covers the recent progress on chemical, enzymatic, and chemoenzymatic lipophilization techniques used to modify the polarity of antioxidants. The partitioning behavior of phenolic antioxidants at the oil–water interface, which can be influenced by the presence of synthetic surfactants and/or antioxidant emulsifiers (e.g., polysaccharides, proteins, and phospholipids), is discussed. In addition, the emerging phenolic antioxidants among phenolic acids, flavonoids, tocopherols, and stilbenes applied in food emulsions are elaborated. As well, the interactions of polar–nonpolar antioxidants are stressed as a promising strategy to induce synergistic interactions at oil–water interface for improved oxidative stability of emulsions.

Algae can be used as an ingredient for food production, as well as a source of marine hydrocolloids and various biologically active substances. There is a lack of studies on the significant floral diversity of the northern seas. It justifies the need not only to determine the species composition of common red algae species, but also to scrutinize its chemical composition and methods to obtain sulfated polysaccharides for further use in the food industry. The chemical composition of a natural mixture consisting of two species of red algae – Ptilota serrata and Ptilota gunneri - gathered in the littoral near Bolshoy Solovetsky Island in the period 2019–2023 had been explored. The research demonstrated that there were no significant differences in the content of ash, protein, carbohydrates and fiber in the mixtures, depending on the month of gathering. When developing a production technology for a water-soluble polysaccharide from a P. serrata and P. gunneri mixture, it was revealed that the rational algae pretreatment mode was maintaining the pH level, duration 1 hour, temperature (22 ± 2) deg C. The polysaccharide extraction modes are the following: temperature (120 ± 2) deg C, duration 1 hour and pH medium level 7. To purify the polysaccharide extract, it is most rational to use activated carbon in an amount of 0.5–1.0% by extract weight, duration (60 ± 5) minutes, temperature (98 ± 2) deg C. The water-soluble polysaccharide should be dried using freeze-drying or spray dryers. The authors recommend using a water-soluble polysaccharide from a P. serrata and P. gunneri red algae mixture as a thickener in production such foods as fruit desserts, sauces and jelly-like soft drinks. | Морские водоросли могут использоваться для производства продуктов питания, как источник морских гидроколлоидов и различных биологически активных веществ. Значительное флористическое многообразие северных морей практически не изучено, что обосновывает необходимость не только определения видового состава массовых видов красных водорослей, но и исследования их химического состава и способов получения сульфатированных полисахаридов с целью их дальнейшего применения в пищевой промышленности. Представлены результаты исследования химического состава природной смеси, состоящей из двух видов красных водорослей – Ptilota serrata и Ptilota gunneri, собранных на литорали у о. Большой Соловецкий в период 2019–2023 гг. Показано, что в смесях отсутствуют значимые различия в содержании золы, белка, углеводов и клетчатки в зависимости от месяца их сбора. При разработке технологии получения водорастворимого полисахарида из смеси P. serrata и P. gunneri, установлено, что рациональным режимом предобработки водорослей является поддержание рН среды, продолжительность 1 ч, температура (22 ± 2) град. С. Экстрагирование полисахарида следует проводить при температуре (120 ± 2) град. С, продолжительности 1 ч и рН среды 7. Для очистки экстракта полисахарида наиболее рационально использовать активированный уголь в количестве 0,5–1,0% к массе экстракта, продолжительность (60 ± 5) мин, температура (98 ± 2) град. С. Сушку водорастворимого полисахарида следует проводить с использованием сублимационной или распылительной сушилок. Рекомендовано использовать водорастворимый полисахарид из смеси красных водорослей P. serrata и P. gunneri в качестве загустителя при изготовлении таких пищевых продуктов, как десерты фруктовые, соусы и кисели питьевые.