**1.7 The probiotics of next generation**

The idea of traditional probiotic products, taken from a limited number of microorganisms, is connected to the observation of the health benefits to both humans and *Probiotics in Processed Dairy Products and Their Role in Gut Microbiota Health DOI: http://dx.doi.org/10.5772/intechopen.104482*

animals from the daily consumption of LAB-fermented food. The word 'probiotic' was therefore associated with bacteria that promote health [18]. The development of knowledge of human microbiota of intestine and its importance for disease and health has led to the discovery of several new bacteria that plays a significant role in the health of human through therapeutic modulation of the intestinal microbiota and are called NGP. The study is very much in the interest of investigating the probiotic potential of commensal bacteria. NGPs are defined as "living micro-organisms identified by comparative analyses which provides benefits to health of the host when properly administered".

### **1.8 Probiotics in fermented milk**

The largest existence of probiotic products in the dairy sector is fermented milk. Several studies have successfully applied probiotic strains to milk fermentation and have induced desirable textural properties, that is apart from inducing health-promoting effects. Highly nutritional value makes its widespread availability and the most widely utilized probiotic milk products. Many commercially manufactured probiotics fermented dairy products are commonly used throughout the world (**Table 2**). Gao in 2019 described that the probiotic products of Kefir and Koumiss are the natural fermented milks mostly used in many parts of the world. Many studies have indicated that probiotic strains are incorporated in traditionally fermented milks that aids to improve their positive health impacts. For example, in a natural milk product (lait curd) of Senegal, Parker et al. [19]


**Table 2.**

*Probiotics in the dairy industry.*

integrated *L. rhamnosus* GG. B. lactic Bi-07 and *L. acidophilus* NCFM, Wang et al. [20] have been integrated into natural milk that aids to improve health of intestine and the immunity of host cell. Many probiotic bacteria in conjunction with traditional probiotic bacteria that are reported to be use in fermented milk to improve the flavor and other characteristics [21, 22], that was linked with functional food. In yogurt*, Streptococcus Thermophilus* and *Lactobacillus delbrücckii* sub specie *bulgaricus, Lactobacillus plantarum* P-8 fermentation have the capacity to improve the yogurt flavor profile by producing 3-methylbutan, acetone, onanal, 2-heptanone, hexanale, (E)-2-octenal and 2-nonanone, compared to controls [23]. In the same way, a high acetic acid, acetoin, 2-butanone, caproic acid, butyric acid, and 2-pentanone content were found in fermented milk containing *L. casei* DN-114001 compared to control group [24].

#### **1.9 Probiotics in yogurt**

Yogurt is a functional ingredient that contain probiotics, so there is great interest in producing probiotic yogurts that are either fermented or incorporated into yogurts with different strains of probiotic. Several commercially produced probiotic yogurts are widely utilized worldwide. A standard yogurt is a fermented milk product traditionally made of *L. delbrueckii* subsp. *bulgaricus* and *S. thermophilus* by fermenting the milk. As yogurt starter cultures can survive in human GI tract [25]. These may be considered probiotic because they have health-promoting effects [26]. However, all the strains of the yogurt starter culture worldwide are not identical and, therefore, the probiotic potential of yogurt starter culture in general remains controversial.

The physiochemical, sensory, and microbial characteristics of the yogurts produced by many probiotic strains comparable to the traditionally produced yogurts are much better in many cases. Of course, certain probiotics, such as *L. plantarum* and *L. acidophilus*, can reduce the bisphenol A (estrogenic substance) content of yogurts considerably [27]. The yogurt metabolism leads to large amounts of unmetabolized lactose and residual galactose in yogurts, which have been shown to be more metabolized (full use of lactose and efficient galactose degradation) by probiotic *L. plantarum* WCFS11 [28].

#### **1.10 Probiotic butter and cream**

There have been several products in which probiotic products have been incorporated due to its widespread benefits, and butter is also used. This is not limited to fermented milk, yogurt, and cheese. Butter, mainly made up of fats, has many

#### *Probiotics in Processed Dairy Products and Their Role in Gut Microbiota Health DOI: http://dx.doi.org/10.5772/intechopen.104482*

health advantages. Emergent evidence, however, suggests that many cardiovascular diseases and diabetes have a high content of saturated fatty acids in butter [29]. Some probiotic bacteria have been reported to reduce the cholesterol content of cream and butter [30] *(L. casei* subsp. For example, in cultivated cream creams high contents of capric, butyric and caproic acid were produced when a blend of probiotic strains, including *Bifidobacterium bifidum, L. acidophilus, S. thermophilus,* and *L. bulgaricus*, was used in the fermentation of creams enriched by 2% (each) sunflower oil, hazelnut oil and soy oil [31]. The increase of the contents of linoleic and α-linolenic acid in probiotic cream in relation to control cream was observed in another study following Bifidobacterium lactis fermentation [32]. In nondairy butters, for instance the peanut and sunflower-produced butters, cocoa and flaxseed oils, probiotics are more commonly used.

#### **1.11 Probiotics in powdered milk and infant formulas milk powder**

Probiotics aid in development of an effective immune system by changing the microflora of the intestine in infants. Probiotics and prebiotics are increasingly added to infant formulae. Probiotic dispensation of bifidobacterial and the strains of lactobacilli in neonatology has developed in worldwide. *B. bifidum* and *L. acidophilus,* dispersed into infant formula (109 CFU/250 mg tablet), have been reported to continue to be more resistant by comparing with breast milk, after storage capacity at 4°C or 6 h [33].

### **1.12 Technological challenges for dairy products viability**

The survival of probiotics is highly crucial as it provide the highly recommended efficiency of probiotics products. During food manufacturing, storage, and gastrointestinal movement, probiotics face multiple stress situations [34]. A minimum of 106 CFU/g of B. bifidum and 107 CFU/g of L. acidophilus in fermented milk are required for several international standards. The probiotic fermented milk should contain at least 107 CFU/ml of live bifidobacteria at the time of consumption in Japan (according to its Association of fermented milk and lactic acid drinking) [35]. The incidence of oxygen in processed dairy products has an impact on most of the probiotic strains and their survival. The oxygen-induced toxicity in milk products poses a major technological obstacle to the development of probiotic fermented milk and yogurt. *Bifidobacterium* species have an anaerobic metabolism of an intestinal origin, which implies that they depend completely on fermentation.
