The aim of this study was to investigate the survival of probiotics (Lactobacillus acidophilus NCFM, Lactobacillus rhamnosus HN001 and Bifidobacterium lactis HN019) in milk chocolate masses prepared at temperatures 35 °C and 40 °C. The influence of probiotics and preparation temperature on rheology, particle size distribution and sensory properties of the chocolates, was examined during 6 months of storage at 20 ± 2 °C. An inoculation temperature of 40 °C significantly improves the rheological and sensory properties of probiotic chocolate, as well as leading to the survival of L. acidophilus NCFM and L. rhamnosus HN001 strains. After 6 months of storage, the survival of these strains was above 90%, with a viable cell count of about 8.1 log(CFU g⁻¹). An inoculation temperature of 40 °C provides higher scores of overall sensory quality (4.52–4.68), higher quality category (excellent), lower maximal viscosity (for 1.2 Pa s) of chocolates, than a temperature of 35 °C. Compared to the chocolate without probiotics, those inoculated at 40 °C achieved less increase in volume weighted mean diameter distribution (average 0.8%) than chocolates inoculated at 35 °C. Based on the results reported in this paper, seeding of the probiotics in industrial conditions can be done in the mixing tank (at 40 °C) before the phase of chocolate shaping. Addition of probiotics at this stage facilitates the manufacturing process, improves the overall quality of chocolate and preserves the probiotics as a key component of this type of product.

Beverages produced by fermentation of whey have significantly lower viscosity, milder flavour and less viability of probiotic microorganisms compared to those obtained by fermentation of milk. Therefore, it is necessary to choose an adequate combination of cultures and supplements that can enhance these characteristics of the final product. The main objectives of this paper were to study the influence of milk and additional probiotic strain Lactobacillus rhamnosus ATCC 7469 on the quality attributes of a fermented whey-based beverage containing commercial ABY-6 starter culture. To formulate a beverage that meets the required criteria for probiotics, supplementation of whey with 30% milk and its fermentation by ABY-6 co-cultured with L. rhamnosus is advisable. The obtained whey-based beverage has desirable texture and sensory quality attributes similar to traditional products and meets consumers' demands. The beverage contains 7.49 log(CFU mL⁻¹) probiotic bacteria, expresses antioxidant activity of 45.1%, satisfactory sensory characteristics and has a shelf life of at least 20 days.

The aim of this study was to improve the mechanical stability of biopolymer carriers and cell viability with addition of chitosan coating during fermentation process and product storage. Dairy starter culture (1% (w/v)) was diluted in whey and mixed with sodium alginate solution and the beads were made using extrusion technique. The mechanical stability of coated and uncoated beads, the release behavior, and the viability of encapsulated probiotic dairy starter culture in fermented whey beverages were analyzed. The mechanical properties of the beads were determined according to force-displacement and engineering stress-strain curves obtained after compression testing. It was observed that addition of chitosan as a coating on the beads as well as the fermentation process increased the elastic modulus of the calcium alginate-whey beads and cell survival. The current study revealed that the coating did not significantly improve the viability of probiotics during the fermentation but had an important influence on preservation of the strength of the carrier during storage. Our results indicate that whey-based substrate has positive effect on the mechanical stability of biopolymer beads with encapsulated probiotics.

This study compares the rheological, thermal, and textural characteristics of four types of chocolate—white, milk, ruby, and dark—produced by the same manufacturer. White, milk, and ruby chocolates contain 36% fat, while dark chocolate has 39%. Cocoa content varies from 28% in white, 33% in milk, 47% in ruby, to 70% in dark chocolate. Rheological properties were assessed with a rotational rheometer, while density was measured with a gas pycnometer. Particle size distribution (PSD) was evaluated using laser diffraction, and thermal properties were analyzed with differential scanning calorimetry (DSC). The DSC results indicated that enthalpy increased with cocoa content, whereby dark chocolate showed the highest value (55.04 J g⁻¹) and white chocolate the lowest (35.3 J g⁻¹). PSD followed a monomodal pattern; dark chocolate had the smallest particles, leading to the highest hardness. Density ranged from 1.2773 to 1.2067 g∙cm⁻³. The results from classical rotational rheological measurements were in accordance with oscillatory measurements. Rheological measurements confirmed that the Casson yield stress was the highest for milk chocolate (17.61 Pa). The viscosity values decreased with increasing shear rate for all chocolates. All chocolate samples showed strong shear-thinning behavior up to a 100 s⁻¹ shear rate. Oscillatory measurements showed the paste-like nature of all samples, i.e., storage modulus G’ dominates loss modulus G’’ at small shear stress values, and the complex modulus G*, which represents the stiffness, varied as follows: milk > white > dark > ruby. This study offers valuable insights into the properties of chocolates during production and storage, helping manufacturers anticipate key characteristics for new confectionery products.