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Aim of this work was the development of integrated and complex encapsulating systems that will provide more efficient protection to the probiotic strain Bifidobacterium animalis subsp. lactis (BB-12) in comparison to the conventional plain alginate beads. Within the scope of this study, the encapsulation of BB-12 through emulsification followed by external gelation was performed. For this purpose, a variety of alginate-based blends, composed of conventional and novel materials, were used. The results demonstrated that alginate beads incorporating 1% carrageenan or 2% nanocrystalline cellulose provided great protection to the viability of the probiotic bacteria during refrigerated storage (survival rates of 50.3% and 51.1%, respectively), as well as in vitro simulation of the gastrointestinal tract (survival rates of 38.7 and 42.0%, respectively). The incorporation of glycerol into the formulation of the beads improved the protective efficiency of the beads to the BB-12 cells during frozen storage, increasing significantly their viability compared to the plain alginate beads. Beads made of milk, alginate 1%, glucose 5%, and inulin 2% provided the best results in all cases. The microstructure of beads was assessed through SEM analysis and showed absence of free bacteria on the surface of the produced beads. Consequently, the encapsulation of BB-12 through emulsification in a complex encapsulating system was proved successful and effective.

Probiotic strains are claimed to confer health benefits to human organisms when consumed in adequate amounts. Thus, over the last decades there has been an increased interest in the production of functional foods containing probiotic bacteria. However, in order to display optimal probiotic functionality, these bacteria should survive through the gastrointestinal tract (GI) in high populations, reaching 106-107cfu (colony-forming unit)/g or mL at the end of product's shelf life. The food products that can be used as probiotic bacteria carriers exhibit limitations concerning the viability of the cells, associated with parameters such as the acidity of the food matrices or their processing and storage conditions. Moreover, the acid environment of the GI system may be crucial for their survival. Thus, techniques such as microencapsulation and enrichment with prebiotic substances are proposed for their protection. Aim of this review is to present the bacterial strains exhibiting probiotic properties, the microencapsulation techniques which are applied for their protection, as well as their advantages and disadvantages. Finally, the characteristics of the most important food products that have been used as possible matrices for microencapsulated probiotic cells are described.

The aim of this work was the evaluation of the breadmaking potential of spelt flour when combined with wheat flour in various proportions, both in freshly baked and frozen form, and determine the optimal ratio for products with satisfactory quality characteristics. Freshly baked samples were prepared using different spelt–wheat flour mixtures ranging from 0 to 100% spelt at 10% intervals, while batches containing 0, 30, 50, 80, and 100% spelt were prepared in the case of frozen dough samples. The characteristics of the final baked products (dough volume expansion, specific volume, crust and crumb color, hardness, and water activity) were evaluated. Results showed that spelt flour proportions up to 20% provide bread with quality and sensory characteristics similar to wheat, while proportions higher than 70% lead to products with inferior properties. Therefore, samples with spelt content between 30 and 60%, although slightly degraded, remained highly acceptable.

Spelt flour has become increasingly popular due to its superior nutritional properties. Aim of this work was to conduct a comparative evaluation of the chemical composition of wheat and spelt flour, their dough rheology and breadmaking properties. Flours’ comparison included the determination of their moisture, ash, protein, gluten, gliadin, glutenin, starch and total carbohydrates content. Their rheological properties were also analyzed through farinograph and extensiograph. The protein fractions of the two flours were evaluated by electrophoresis. Finally, each flour was separately used for breadmaking and the characteristics of the resulting bakery products (specific volume, dough swelling, crust and crumb color, hardness and water activity), were evaluated. Although spelt flour has higher protein content, it contains less gluten, while wheat flour provides a stronger and more elastic dough with superior breadmaking properties. Bread from spelt flour exhibits lower specific volume, darker crumb and crust color and increased crust and crumb hardness.

Due to the shift towards healthy lifestyles, the food industry focuses on expanding the production of probiotic food products. Τhe incorporation of probiotic bacteria into the food matrix is challenging because various processes can damage cells’ viability. In this study, an innovative and advanced encapsulation approach combining the extrusion technique with the technique of double emulsification (W1/O/W2 emulsion system) is proposed for the protection of Bifidobacterium lactis (BB-12). Different W1/O/W2 emulsion formulations were investigated using various encapsulating agents as wall materials for satisfactory encapsulation of BB-12 cells. The probiotic cells were incorporated in the double emulsion prior to extrusion and their viability was evaluated by exposing them to different storage temperatures and various pH values, as well as to simulated gastrointestinal fluids. The results demonstrated that the viability of probiotics, when using the proposed encapsulation system, maintained above 6 log cfu g−1 during storage at 4 °C and −18 °C for 4 weeks, while the BB-12 cells encapsulated through conventional extrusion were decreased significantly (survival rate 46.8%) after 15 days of storage. Moreover, this novel system provides high survival rates during the in vitro simulation of the gastrointestinal system (up to 86.1%) and at various pH environments (up to 98.5%).