2.1 Microencapsulated probiotic mixed fruit juice

their functionalities during food processing and storage [17]. Several strains of Lb. plantarum, Lb. acidophilus, and Lb. casei can grow in fruit matrices due to their

ria, such as probiotic strains used, pH, the presence of hydrogen peroxide and dissolved oxygen, buffering form, storage temperature, the nature of the ingredi-

In order to exert beneficial effects on health, the number of viable cells of probiotic microorganisms should be located above 10<sup>6</sup> CFU.g<sup>1</sup> in the product for consumption, available over the entire shelf life. Therefore, the preservation of probiotic cultures in products during storage is of extreme importance [49].

During food storage different factors may affect the viability of probiotic bacte-

In this context, microencapsulation of probiotic cells has been widely studied as a technique to improve the stability of these microorganisms by protecting them from unfavorable environments [17]. Microencapsulation also has a potential effect on reducing post-fermentation acidification and possible negative sensory effects of

Among the microencapsulation technologies, spray drying and freeze drying are the most commonly used. However, spray drying is the most effective for largescale industrial production because it is a continuous, rapid process and has relatively low cost and high reproducibility [51, 52]. It is suggested as a technique that improves the survival of probiotics during food processing and storage, as well as confers protection of probiotics against subsequent exposure to the harsh conditions of the gastrointestinal tract, as this process gives a coating to the cells, protecting

Among the advantages of atomization, a distinguished one is the ability to handle heat-sensitive materials with high surface area/droplets volume ratio, resulting in shorter time of exposition to drying temperature [54]. Besides

protecting probiotic cells from adverse conditions, powders obtained through spray dryer have good reconstitution and low water activity and are suited for storage at ambient temperature, what it is desirable, especially in commercial applications, due to higher operational costs associated with cooled storage, transport, and dis-

The characteristics of the powder produced in driers depend mainly on the operational variables of the drier (air inlet and outlet temperatures), on the product composition, solid concentration, feed flow rate, and also on the type of encapsu-

Several studies reported that microencapsulation by spray dryer might provide a more favorable anaerobic environment for sensitive probiotic bacteria, as well as a physical barrier from the harsh acidic conditions of fruit juice [58]. The addition of probiotics in different fruit juices to produce functional beverages microencapsulated by spray drying has also been reported [21, 25, 27, 29].

The most commonly used carrier materials for encapsulation are maltodextrin. Maltodextrin (MD) is a polysaccharide, which molecular weight and properties depend on the hydrolysis process employed to obtain it from starch. Maltodextrin is classified by its dextrose equivalent (DE) which measures the amount of reducing

The wall material is one of the most important parameters in the food microencapsulation processes. Its chemical composition and structure can affect the quality of the powdered product and criteria, such as solubility, apparent density, absolute density, porosity, particle size distribution, morphology, hygroscopicity, cell via-

However, to date there are no reports on the use of various probiotic microor-

sugars present in a sugar product, relative to dextrose [59–61].

bility, water activity, moisture content, and sensory evaluation [61, 62].

ganisms incorporated into a mixed beverage. In view of this, aiming at

tolerance to acidic environments [46].

probiotic food products [50].

tribution difficulties [55, 56].

38

ents added, and food matrices [23, 47, 48].

Prebiotics and Probiotics - Potential Benefits in Nutrition and Health

them from the outside environment [53].

lating agent used in the formulation [57].

In recent years our research group has been carrying out studies with microencapsulation of juices from various fruits, using maltodextrin as the main encapsulating agent. In a recent study [63], with mixed juice of tropical fruits, the process was optimized in order to obtain products with better sensorial and nutritional characteristics. Based on these results, in order to meet the growing demand for functional foods, probiotic microorganisms were added.

The study related to the process of addition of probiotics to mixed juice in powder is an innovation, consisting of a new food product. Thus, the patent of product and process category was registered, at Brazil's National Institute of Industrial Property with Patent nature of Invention, under register number BR 102019 009006 5.

The objective was to develop a novel nondairy probiotic product, composed of mixed juice with three Lactobacillus microencapsulated by spray drying using maltodextrin DE 5.

Currently there is a growing market for juices composed of more than one fruit, and this tendency is most observed in products that use tropical fruits. Tropical fruits are widely accepted by consumers and are important sources of antioxidant compounds. For this reason the acerola and siriguela were selected.

Acerola (Malpighia emarginata D.C.) is a fruit native to Central America and Northern South America, with some of its largest plant area in Brazil, which has been increasingly produced, because of their high vitamin C contents from 700 to 1400 mg/100 g<sup>1</sup> [64–66]. The siriguela (Spondias purpurea L.) is a fruit from Anacardiaceae family originally from Central America and widespread in all tropical countries, mainly in the northeast region of Brazil. It is a small yellow fruit, with a pleasant aroma and taste, being a source of carotenoids [67, 68]. Thus, acerola and siriguela juice is an interesting nondairy matrix for a probiotic beverage.

The viability of probiotic bacteria is the most important parameter in the spray drying process using microorganisms due to heat inactivation and exposure to dehydration, and maximum viability is there for the major goal for this type of product [25, 69]. Probiotic mixed powder juice with maltodextrin DE 5 presented viable cell counts above 6.0 log CFU.g<sup>1</sup> (Table 2), which is the minimum


#### Table 2.

Physical properties and microbial viability of acerola and siriguela probiotic mixed juice microencapsulated by spray drying using air inlet temperature 140°C, feed flow rate 0.60 L/h, and 10% maltodextrin DE 5.

recommended level for probiotics in food products necessary to produce therapeutic benefit [25, 70].

Probiotics'survival during spray drying can also be attributed to the strong adherence to the carrier, which protects cells from high acidic and bile conditions. Overall, maltodextrin is confirmed to serve as a good encapsulating matrix as well as a moderate prebiotic for high survival of probiotics. The sugars present in juice may also have contributed to the survival during spray drying since sugars act as thermoprotectants [71].

Moisture and water activity are important indexes for spray-dried powders due to their effects on the shelf life of the product; a large amount of retained water can accelerate degradation reactions and microorganism growth [72]. It is necessary that its equilibrium moisture content is less than 5 g water/100 g of dry solid and its water activity is in the range from 0.1 to 0.4, ensuring greater stability for dry food [73]. The moisture and water activity for probiotic mixed powder juice (Table 2) are in agreement with the study of [73]. Values similar were obtained by [20, 27, 30] studying orange, lychee, and orange juice probiotic microencapsulated by spray drying, respectively.

Hygroscopicity is the ability of a material to attract and hold moisture from the environment. It is generally calculated from the weight gain after storing the food powder in a high humid desiccator (relative humidity more than 60%) for a period (generally 1 week) [74, 75]. The hygroscopicity value (Table 2) was similar compared to other probiotic microencapsulated formulation [27] and much larger than [21]. The hygroscopicity can be easily controlled by using suitable packaging, maintaining the integrity of the product without significant changes.

Solubility, the ability of a powder to form solution or suspension in water, is defined as the most reliable criterion to evaluate the behavior of powder in an aqueous solution. This parameter shows the ability of the spray-dried powder to form solution or suspension in water [76]. Solubility of powders can be affected by many parameters such as initial composition of the raw material to be microencapsulated by spray-dried, compressed airflow rates, low feed rates, and the carrier agents [77]. In this study, high solubility values were obtained with maltodextrin DE 5 (Table 2). The characteristics of solubility normally contradict to apparent density; the powder showing high solubility should have low apparent density [78].

on the surface of the microparticles may be associated with shrinkage of the wall material during initial stages of the process and temperature used in the drying chamber [83, 84]. With these results, a great potential for the use of such powders

Scanning electron microscopy (SEM) photographs of acerola and ciriguela probiotic mixed juice microencapsulated by spray drying using air inlet temperature 140 °C, feed flow rate 0.60 L/h and 10%

Particle size distribution of acerola and ciriguela probiotic mixed juice microencapsulated by spray drying using

air inlet temperature 140 °C, feed flow rate 0.60 L/h and 10% maltodextrin DE 5.

Prebiotics and Probiotics - Potential Benefits in Human Nutrition and Health

DOI: http://dx.doi.org/10.5772/intechopen.89155

The development of new functional food products is very challenging, and it has to complete the consumer's expectations for palatable and healthy products. Probiotic cells can be stabilized with microencapsulation to preserve them from detrimental processing and storage factors such as high acidity and low pH. Therefore, there is a potential market for nondairy probiotics such as vegetable-based products, fruit-based products, cereal- and legumes-based products, confectionary products, and breakfast cereals. The present investigation concludes that it is possible to obtain probiotic foods from several matrices, including fruit juice. The acerola and siriguela mixed juice is a suitable medium for the incorporation of Lactobacillus

for the culture of probiotics, since it already contains beneficial nutrients such as minerals, vitamins, dietary fibers, and antioxidants. The microencapsulation by spray drying of probiotics in acerola and siriguela mixed juice is a viable alternative,

), demonstrating to be an ideal substrate

in the food industry is observed (Figure 2).

spp. with suitable counts (>6 log CFU.g<sup>1</sup>

3. Conclusion

41

maltodextrin DE 5.

Figure 1.

Figure 2.

The absolute density of the particle matches the actual density of the solid and does not consider the spaces present between the particles, unlike the apparent density. A similar result with this study (Table 2) was reported by [75] using maltodextrin DE 10 for açai pulp drying.

The higher values of porosity indicate the presence of a larger number of spaces between the particles, containing oxygen available for degradation reactions [79]. In this study (Table 2), lower value of porosity was obtained. In this way, the maltodextrin DE 5 is suitable for the spray dryer process. The efficacy of low-DE maltodextrin as drying carriers is due to the encapsulating property and low moisture diffusivity [80].

Particle size distribution is an important physical property that directly affects the application of microcapsules into food formulations [81]. The microcapsules exhibited lower particle size distribution (7.07 μm 0.03). Small particles are preferred in food formulations for ensuring homogeneity and quality, since they have large surface area and enable interaction with microorganisms favoring the microbial reactivation [82] (Figure 1).

The morphological characteristics of the particles showed spherical shapes with various sizes that are features of spray-dried powders and surfaces with wrinkled predominance and few particles with smooth surface. The occurrence of roughness Prebiotics and Probiotics - Potential Benefits in Human Nutrition and Health DOI: http://dx.doi.org/10.5772/intechopen.89155

Figure 1.

recommended level for probiotics in food products necessary to produce therapeu-

Prebiotics and Probiotics - Potential Benefits in Nutrition and Health

Probiotics'survival during spray drying can also be attributed to the strong adherence to the carrier, which protects cells from high acidic and bile conditions. Overall, maltodextrin is confirmed to serve as a good encapsulating matrix as well as a moderate prebiotic for high survival of probiotics. The sugars present in juice may also have contributed to the survival during spray drying since sugars act as

Moisture and water activity are important indexes for spray-dried powders due to their effects on the shelf life of the product; a large amount of retained water can accelerate degradation reactions and microorganism growth [72]. It is necessary that its equilibrium moisture content is less than 5 g water/100 g of dry solid and its water activity is in the range from 0.1 to 0.4, ensuring greater stability for dry food [73]. The moisture and water activity for probiotic mixed powder juice (Table 2) are in agreement with the study of [73]. Values similar were obtained by [20, 27, 30] studying orange, lychee, and orange juice probiotic microencapsulated by spray

Hygroscopicity is the ability of a material to attract and hold moisture from the environment. It is generally calculated from the weight gain after storing the food powder in a high humid desiccator (relative humidity more than 60%) for a period (generally 1 week) [74, 75]. The hygroscopicity value (Table 2) was similar compared to other probiotic microencapsulated formulation [27] and much larger than [21]. The hygroscopicity can be easily controlled by using suitable packaging,

Solubility, the ability of a powder to form solution or suspension in water, is defined as the most reliable criterion to evaluate the behavior of powder in an aqueous solution. This parameter shows the ability of the spray-dried powder to form solution or suspension in water [76]. Solubility of powders can be affected by

microencapsulated by spray-dried, compressed airflow rates, low feed rates, and the carrier agents [77]. In this study, high solubility values were obtained with maltodextrin DE 5 (Table 2). The characteristics of solubility normally contradict to apparent density; the powder showing high solubility should have low apparent

The absolute density of the particle matches the actual density of the solid and does not consider the spaces present between the particles, unlike the apparent density. A similar result with this study (Table 2) was reported by [75] using

The higher values of porosity indicate the presence of a larger number of spaces between the particles, containing oxygen available for degradation reactions [79]. In this study (Table 2), lower value of porosity was obtained. In this way, the maltodextrin DE 5 is suitable for the spray dryer process. The efficacy of low-DE maltodextrin as drying carriers is due to the encapsulating property and low moisture

Particle size distribution is an important physical property that directly affects the application of microcapsules into food formulations [81]. The microcapsules exhibited lower particle size distribution (7.07 μm 0.03). Small particles are preferred in food formulations for ensuring homogeneity and quality, since they have large surface area and enable interaction with microorganisms favoring the

The morphological characteristics of the particles showed spherical shapes with various sizes that are features of spray-dried powders and surfaces with wrinkled predominance and few particles with smooth surface. The occurrence of roughness

maintaining the integrity of the product without significant changes.

many parameters such as initial composition of the raw material to be

tic benefit [25, 70].

thermoprotectants [71].

drying, respectively.

density [78].

diffusivity [80].

40

maltodextrin DE 10 for açai pulp drying.

microbial reactivation [82] (Figure 1).

Particle size distribution of acerola and ciriguela probiotic mixed juice microencapsulated by spray drying using air inlet temperature 140 °C, feed flow rate 0.60 L/h and 10% maltodextrin DE 5.

#### Figure 2.

Scanning electron microscopy (SEM) photographs of acerola and ciriguela probiotic mixed juice microencapsulated by spray drying using air inlet temperature 140 °C, feed flow rate 0.60 L/h and 10% maltodextrin DE 5.

on the surface of the microparticles may be associated with shrinkage of the wall material during initial stages of the process and temperature used in the drying chamber [83, 84]. With these results, a great potential for the use of such powders in the food industry is observed (Figure 2).
