Lactic Acid Bacteria: Their Applications in Foods

Mini Reviewe

J Bacteriol Mycol. 2018; 5(2): 1065.

Lactic Acid Bacteria: Their Applications in Foods

Bintsis T*

¹Department of Agricultural Technology, TEI of West Macedonia, Kozani, Greece

*Corresponding author: Bintsis T, Department of Agricultural Technology, TEI of West Macedonia, Kozani, Greece

Received: February 27, 2018; Accepted: March 29, 2018; Published: April 05, 2018

Abstract

Lactic acid bacteria (LAB) are a heterogeneous group of bacteria which plays a significant role in a variety of fermentation processes. They ferment food carbohydrates and produce lactic acid as the main product of fermentation.

The main application of LAB is as starter cultures, with an enormous variety of fermented dairy, meat, fish, fruit, vegetable and cereal products. Besides, LAB contribute to the flavor, texture and nutritional value of the fermented foods, and such applications as adjunct, bio-protective, probiotic cultures and various applications in food industry are discussed.

Keywords: Lactic Acid Bacteria; Applications; Fermented Foods

Introduction

Lactic acid bacteria (LAB) play an important role in food, agricultural, and clinical applications. The general description of the bacteria included in the group is gram-positive, nonsporing, nonrespiring cocci or rods, which produce lactic acid as the major end product during the fermentation of carbohydrates [1]. The common agreement is that there is a core group consisting of four genera; Lactobacillus, Leuconostoc, Pediococcus and Streptococcus. Recent taxonomic revisions have proposed several new genera and the remaining group now comprises the following: Aerococcus, Alloiococcus, Carnobacterium, Dolosigranulum, Enterococcus, Globicatella, Lactococcus, Oenococcus, Tetragenococcus, Vagococcus, and Weissella [2]. Their importance is associated mainly with their safe metabolic activity while growing in foods utilizing available sugar for the production of organic acids and other metabolites. Their common occurrence in foods along with their long-lived uses contributes to their natural acceptance as GRAS (Generally Recognized as Safe) for human consumption [3]. The EFSA’s ‘Panel on Biological Hazards (BIOHAZ)’ has concluded that the fermenting bacteria associated with food, whether resistant to antibiotics or not with the possible exception of enterococci do not pose a clinical problem [4]. However, they can act as a reservoir for transferable resistance genes. Strains with genes transferable in such a way could inter the food chain and increase the probability of a transfer to food associated intestinal pathogenic organisms.

The three main pathways which are involved in the manufacture and development of flavour in fermented food products are 1) glycolysis (fermentation of sugars), 2) lipolysis (degradation of fat) and 3) proteolysis (degradation of proteins) [1,5-9]. Lactate is the main product generated from the metabolism of carbohydrates and a fraction of the intermediate pyruvate can alternatively be converted to diacetyl, acetoin, acetaldehyde or acetic acid (some of which can be important for typical yogurt flavours). The contribution of LAB to lipolysis is relatively little, but proteolysis is the key biochemical pathway for the development of flavour in fermented foods [10,11]. Degradation of such components can be further converted to various alcohols, aldehydes, acids, esters and sulphur compounds for specific flavour development in fermented food products [10,11].

The genetics of the LAB have been reviewed [12-18] and complete genome sequences of a great number of LAB have been published [19] since 2001, when the first genome of LAB (Lactococcus lactis ssp. lactis IL1403) was sequenced and published [20].

Applications of LAB

Starter cultures for fermented foods

Fermented foods are produced through fermentation of certain sugars by LAB and the origins of them are lost in antiquity. The most commonly LAB used, nowadays, as starter cultures in food fermentations are shown in Table 1. For a detailed classification of starter cultures see [21,41,42].

Citation: Bintsis T. Lactic Acid Bacteria: Their Applications in Foods. J Bacteriol Mycol. 2018; 5(2): 1065.