**2.** *Lactobacillus* **in food industry**

*Lactobacillus* has a long history of use in biotechnology predominantly in manufacturing and conserving food ingredients by the process of fermentation, yoghurt, cheese, kefir, sauerkraut and many other fermented food products productions with the addition of animal feeds manufacture [13]. Further bioprocess technology has developed the specified production aids and procedures for food and feed ingredients [14].

*Lactobacilli* were the first microbes used by human beings for processing foods and preservation of foods by inhibiting other microbial invasions that can cause food spoilage and ultimately results in foodborne illness [15, 16]. *Lactobacillus* is a significant genus to recent food and feed technologies, not only because of its cumulative interest in valuable functional properties. The dairy industry and self-care health productions are dynamically engaged in promoting the usage of *Lactobacilli* in food, [17]. Some traditional fermented foods (**Table 1**) based on *Lactobacillus* fermentation from different origins, cultures, civilizations, customs, social relations and sometimes customized with religions were reported by Food and Drug Administration [18, 19]. Because of the characteristic to produce organic acids by using carbohydrates *Lactobacilli* have extensive application in the food industry [20].

*Lactobacilli: Application in Food Industry DOI: http://dx.doi.org/10.5772/intechopen.106856*


#### **Table 1.**

*Traditional foods containing lactobacilli.*

#### **2.1 Lactobacilli as starters in food processing industries**

*Lactobacilli* are mainly used as a starter culture in the contemporary food processing industry. The starter culture may contain only one pure strain or a combination of strains from different species of microbes [20]. Starter cultures can be well-defined as the enormous number of cell preparations, any of a single strain type or an assortment of two or more microbial strain/species that are supplemented in foods to get the advantage of consequent products or compound obtained from their metabolic or enzymatic activity [21]. Since starter cultures are used in food production settings to accomplish processes of fermentation, their usage is globally a common practice in food manufacturing industry. This has led to the commercialization of numerous products such as probiotics or starters, bio-protective cultures that are intended to deliver foods with specific nutritional and sensual characteristics, prospective health benefits and assurance of food safety [22]. Starter cultures are practically applied in a wide array of food industries such as the dairy productions for the manufacture of yoghurt, cheese and other fermented

**Figure 1.** *Application of lactobacillus in food industry.*

products from dairy milk [23], sausage manufacture in meat industry [24], in wine and beer industry for the production of alcohol [25, 26], production of vinegar [27], preparation of soy and rice-based oriental foodstuffs [28], fermented cereals and bakery products [29], and in making of fermented products from fruits and vegetables [30–32]. **Figure 1** clearly illustrates the industrial potential of lactobacilli.

Starter cultures may contain any type of microbes such as bacteria, yeast, mold or any type of fungal culture. But the species of *Lactobacilli* reported in the literature have vast potential for usage as starter culture because of its antimicrobial effects which ultimately prove beneficial for food safety. Potential antimicrobial properties of some lactobacilli have been described by scientists such as *Latilactobacillus sakei* isolated from meat sausages have an antimicrobial effect against *Listeria monocytogenes*, *Salmonella spp.* and *E. coli* in combination of garlic powder and wine [33]. Another strain of *lactobacillus* i.e. *Lactiplantibacillus plantarum* was found effective against pathogenic bacteria of the *Enterobacteriaceae* family when used as a starter in Vacuum packaged products [34].

#### **2.2 Lactobacilli in dairy industry**

The *Lactobacillus* genus comprise a large number of diverse species with relatively large degree of variation and diversity. It is one of the largest genus in the group of lactic acid bacteria of over fifty species [35]. *Lactobacilli* are the important lactic acid producing bacteria and are responsible for the development of microflora in the most dairy products particularly cheese and fermented milk. *Lactobacillus* is

#### *Lactobacilli: Application in Food Industry DOI: http://dx.doi.org/10.5772/intechopen.106856*

the significant microorganism for development of color, flavor and texture of dairy products via acidification owed to lactic acid and by metabolizing milk proteins. The commonly used species of *L***actobacilli** in the dairy industry are *Lb. lactis*, *Lb. casei*, *Lb. rhamnosus*, *Lb. helveticus*, *Lb. plantarum* and *Lb. curvatus* [36]. Moreover, *lactobacilli* are incorporated in the preparation of cheese, yoghurt and fermented milk as probiotic cultures because of their potential benefits for the treatment of acute and chronic inflammation of the gastrointestinal tract [37]. *Lactobacilli* can additionally be used for the preservation of dairy products as they can produce bacteriocins which are usually inhibiting the growth of other non-desired microbes [38]. The species of *Lb. delbrueckii* encompasses three subspecies that is *subsp. bulgaricus*, subsp. *delbrueckii* and subsp. *lactis* [35] are used as a starter culture for yoghurt preparation. The information related to the use of other cultures for yoghurt manufacturing and safety is scarce.

The strain *Lb. paracasei subsp. paracasei* is recovered commonly from ripened cheese and forms a constitute with *Lb. curvatus*, *Lb. plantarum*, *Lb. casei* and *Lb. rhamnosus* is the primary microbiota of the non-starter Lactic acid bacteria group contributing to the process of cheese maturation [39, 40]. Among the species of lactobacilli *Lb. rhamnosus* is one that has been applied as a probiotic organism in functional foods. The strain *Lb. rhamnosus* has been identified and designated with a number HN001, has both probiotic and flavor improving qualities, hence, it can be useful as an adjunct in the manufacturing of cheese to decrease dangerous microflora, improve the flavor of cheese and increase the speed of cheese ripening [41, 42]. *Lactobacillus johnsonii* formerly known as *Lb. acidophilus* has been widely studied because of its probiotic characteristic and is commercialized for production of fermented milk (LC1) products [43]. The *Lb. johnsonii* displays antimicrobial [44–46] and immunomodulatory properties [47, 48] properties. A thermophilic starter culture of *Lactobacillus helveticus* is used in the production of a numeral fermented products of dairy [49] and develops on a comparatively limited number of carbohydrates such as galactose and lactose with typical requirement of few vitamins for growth [50, 51]. Knowledge about the biodiversity of *Lactobacillus* can be employed as a starter culture in different dairy products described in previous literature is provided in the tabulated form (**Table 2**).

#### **2.3 Lactobacilli in non-dairy food products of plant and animal origin**

The species of *Lactobacillus* are useful for production of fermented foods other than dairy such as sauerkraut by fermenting cabbage. Usually, normal microflora of cabbage with added *Lb. plantarum* act as starter and salt like sodium chloride is used for preventing the growth of foodborne pathogenic microorganisms [68]. An additional study reported the use of both *Lb. plantarum* and *Lb. brevis* for production of sauerkraut [69]. Another food product in which the genus *lactobacillus* is involved is pickle where the propagation of starter culture of *Lb. plantarum* is responsible for achieving the desired effect. Another investigation reported the involvement of *Lb. versmoldensis* sp. nov.; *Lb. plantarum*; *Lb. casei*; *Lb. pentosus* for the production of fermented green olives [70–72]. The *Lactobacillus* species such as *Lb. sakei* and *Lb. curvatus* were found in dry sausages [73–75]. A previous study reported the presence of *Lb. sanfranciscensis*, *Lb. reuteri* and *Lb. pontis* in sourdough [76].

*L. acidophilus* was reported in chocolate by Rosell [77] and *Lb. plantarum* was found in juice drinks [78] as well as *Lb. rhamnosus* was described as a microbe found in juice drinks (Valio Gelfilus) GG (ATCC 53103) [64].



#### **Table 2.**

*Species of lactobacilli present naturally or added as starter in dairy products.*

*L. fermentum* has been used extensively as a probiotic strain and may be found in cereal-based fermented foods and many other vegetables [79]. The predominant bacteria of sourdough and cereal based fermented products is *Lb. plantarum* and is a leading microbe because it applied for producing corn dextrins after the reduction of fermentable sugars [80] *Lactobacillus sanfranciscensis* is the leading lactic acid bacteria in sourdough [80] and 14 genome assemblies of *Lb. sanfranciscensis* have been reported [35].

A fermented beverage tea known as Kombucha is prepared by the traditional fermentation process of fermenting sweetened black tea with tea fungus which contains a consortium of yeasts and acetic acid-producing bacteria. The viability of selected strains of *Lactobacilli* throughout the fermentation process of Kombucha and their interaction with tea fermenting fungus and their role in obtaining a tea beverage with improved functional properties were tested by scientists [81] Five wild strains (*Lactobacillus hilgardii*, *L. fermentum*, three strains of *L. plantarum*) isolated from conventional fermented foods and were added separately in Kombucha on the second day of fermentation. The addition of wild species of *Lactobacillus* during fermentation of Kombucha contributed significantly to increasing the lactic acid content of the tea beverage. The strain of *Lactobacillus plantarum* was reported for the highest lactic acid production during Kombucha fermentation. The *L. hilgardii* strain isolated from sour dough exhibited the highest sustainability in Kombucha and also has possible probiotic characteristics. So this strain can be used in Kombucha fermentation.
