Lecture 3 Benefits of - PowerPoint Presentation

Slide1

Lecture

3Benefits of Fermenting Foods

FE308

- Fermentation TechnologySpring 2016

Slide2

1.Improving Food Security

a)Food Preservationb)Salvaging waste foodsc) Removal of anti-nutritional factorsd)Antimicrobial activities Organic acids

Bacteriocins Hydrogen peroxide Diacetyl Ethanol2.Increasing income and employment3.Health benefits a)İmproving nutrition b)Vitamin c)Digestibility d)Lactose intolerance

e)Probiotics f) Cholesterol g)Anticancer effects h)Stimulation of immunological system ı)Medicinal benefits. j)Other4.Improving cultural and social well being5.Malolactic fermentation

Slide3

1.Improving Food Security

Fermentation technologies play an important role in ensuring the food security around the world through improved food preservation, increasing the range of raw materials that can be used to produce edible food products and removing anti nutritional factors.a)Food Preservationb)Salvaging waste foods.

A wide range of waste products are fermented to produce edible food productsc) Removal of anti-nutritional factors.For ex:in Kawal fermentation toxins are romoved from leaves.d)Antimicrobial activities

Organic acids- LAB produce lactic acid, formic acid, propionic acid, acetic acid and it reduce pH and can inhibit undesirable m.o’s. Bacteriocins-Bactericidal polypeptides or proteins and heat stable at acid pH. Hydrogen peroxide-It is bacteriostatic at low concentration and bactericidal at high concentrations

Diacetyl-produced by several species of LAB through metabolism of citrate. Ethanol-inhibitory to other m.o’s.

Slide4

Bacteriocins are ribosomally synthesized single polypeptides or posttranslationally modified ones that are usually inhibitory only to closely related bacterial species

Bacteriocins

Slide5

Bacteriocins of LAB

Main

category

Characteristics

Subcategory

Examples

Class I

Lantibiotics

Type A

Type B

Nisin

Mersacidin

Class II

Nonmodified heat-stable bacteriocins containing

peptides with molecular masses of 10 kDa

Subclass IIa

Subclass IIb

Pediocin AcH

Enterocin FH99

Pediocin 34

Lactacin F and Lactococcin G

Class III

Protein bacteriocins

with molecular masses

of 30 kDa

Helveticin J

Lactacins A and B

Class IV

Bacteriocins that form large complexes with other macromolecules

Leuconosin S

Lactococcin 27

Slide6

SOME USEFUL BACTERIOCINS FOR THE DAIRY & FOOD INDUSTRY

Genus of Bacteria

Lactococcus lactis

subsp. lactisPediococcus acidilactici

Pediococcus peantosaceusLeuconostoc spp.Lactabocillus

sakeLactabocillus plantarumLactabocillus

helveticus Carnabacterium piscicola

Bacteriocin

Produced

Nisin

A,Z

Pediocin

PA-1,

AcH

Pediocin

34

Leucocins

Sakacin

APlantaricinHelveticin JCarnocin/piscicolin

Slide7

Hydrogen Peroxide

Strong oxidising effect on the bacterial cell wall

Can oxidise sulfhydryl groups of cell proteins and membrane lipids

H

2

O

2 producing reactions scavenge oxygen, thereby creating anaerobic environment that is unfavourable for some microorganisms

Antimicrobial activity is enhanced by the presence of Lactoperoxidase and thioccyanate

SCN

-

+ H

2

O

2

OSCN

-

+H

2

O

Slide8

Diacetyl

Identified By Van Neil et al.(1929) as the aroma and flavor component in butter

Produced by species and strains of genera

Lactobacillus

,

Leuconostoc

, Pediococcus and Streptococcus More active against Gram negative bacteria, Yeasts and molds than against Gram Positive bacteria

Reacts with the arginine binding protein of Gram negative bacteria, thereby interfering with the utilization of arginine

Slide9

3.Health benefits

a)İmproving nutritionLactic fermentatiom improves

nutritional value thgrogh incerasing level of aminoacids.Again, they break down large

molecular sized nutrients and incerase digestibility and reduces toxic

metabolites b)VitaminSac. cerevisiae is able to concentrate large

quantities of hiamin,nicotinic acid,biotin an thus form enriched products

.Palm wine inWest Africa is high in vitami B12,which is very important for

people

with

low

meat

intake

.

c)DigestibilityM.o’s produces ceratin enzymes which arenot synthesized by humans such as cellulases.

Slide10

What are Probiotics?

Probiotics are defined as live microbes which when administered in adequate amounts confer a beneficial health effect on the host--- WHO 2002

Lactobacillus

species

L. acidophilusL. casei (rhamnosus)

L. reuteriL. bulgaricusL. plantarumL. johnsonii

L. lactis

Bifidobacterium species

B.

bifidum

B.

longum

B.

breve

B.

infantis

B.

lactis

B. adolescentisOthersBacillus cereus

Non pathogenic Escherichia coli

Saccharomyces

cerevisiae

Enterococcus

faecalis

Streptococcus

thermophilus

Slide11

The Probiotic History

Ellie Metchnikoff, the first scientist who proposed the therapeutic use of lactic acid bacteria.

Lactic acid bacteria were first discovered by Pasteur in 1857

Their isolation from rancid milk was reported in 1878 by Lister.

In 1889 Tissier discovered Bifidobacterium spp.

The first stable cultures of

Lactobacillus casei

strain Shirota were made in 1930 by Dr. Minoru Shirota

Slide12

Why are Probiotics important for Human health?

Antibiotics

Alcohol consumption Stress

Destroy the gut micro flora

Problems in digestion

Problems in absorption of nutrients in the body

Emergence of antibiotic resistant strains

Probiotics

Slide13

Lactobacillus strains:

Acid tolerant

Lactic acid as the major metabolic end product

Bifidobacterium

strains:

Saccharolytic organisms

Produce acetic and lactic acids without generation of CO2

They are lactic acid bacteria (LAB)

Source:

Raw and fermented dairy products

Fresh and fermented plant products

The reproductive and intestinal tracts of humans and other animals

.

Slide14

Features of Probiotics

Non-pathogenicNontoxicResistant to gastric acid

Adhere to gut epithelial tissueProduce antibacterial substancesIt should persist for short periods in the gastro-intestinal tractAble to resist the antibacterial mechanisms that operate in the gutNeed to avoid the effects of peristalsis, which tend to flush out bacteria with foodResistant to the bile acid

Slide15

Mechanism of action of Probiotics

Production of low-molecular-weight antibacterial substance that inhibits both gram-positive and gram-negative enteric bacteria

Also use enzymatic mechanisms to modify toxin receptors and block toxin-mediated pathologyAlso prevent colonization of pathogenic microorganisms by competitive inhibition for microbial adhesion sites

Slide16

Slide17

Mechanism of cholesterol assimilation by Probiotics

Direct

Indirect

Inhibiting the

de novo

synthesis of cholesterol

Decreasing the intestinal absorption of dietary cholesterol

Lactose,

calcium hydroxyl methyl glutarate, uric acid,

whey proteins

Assimilation

Binding

Degradation

Deconjugating the cholesterol to bile salts

Cholesterol assimilation

Slide18

Anticancer effects

Activity of L

. acidophilus and L. casei supplementation in humans helped to decrease levels of these enzymes.

High animal fat and protein DietIncrease the susceptibility to colon cancer by conversion of pre-carcinogens to carcinogens by the intestinal micro flora

=

Enzymes

(Glycosidase, B-

glucuronidase

,

azoreductase

, and

nitroreductase

)

Pre-carcinogens

Active carcinogens

Slide19

Lactose- intolerant individuals

tolerate yogurt mainly due to the supply of lactase activity from the lactic acid bacteria present in the yogurt itself. Lactose deficiency leads to calcium malabsorption Acidic condition = Calcium absorption is more

Production of lactic acid by hydrolysis of milk lactose by Probiotics.

Slide20

Allergy

Degradation/structural modification of antigens.

Normalization of the properties of aberrant indigenous microbiota.Regulation of the secretion of inflammatory mediators.Stimulating immune response and reduction of serum IgE levels.Lactobacillus

and Bifidobacterium improve mucosal barrier function. Probiotics have been shown to reduce the incidence of childhood eczema. Probiotics have been shown to control lactose intolerance.

Slide21

Commercial Probiotic Strains

Probiotic StrainCommercial Product

L. acidophilus LA-5; NCDO 1748Saccharomyces cerevisiae (boulardii) Florastor

Biocodex (Creswell OR) L. casei ShirotaB. breve strain Yakult YakultL. johnsonii Lj-1 (same as NCC533 and formerly L. acidophilus La-1)

LC-1Nestlé (Lausanne, Switzerland) L. reuteri ATCC 55730 ("Protectis") BioGaia Probiotic chewable tablets or drops Streptococcus

oralis KJ3Streptococcus rattus JH145 ProBiora3

Oragenics Inc. (Alachua FL) Lactobacilli rhamnosus PBO1Lactobacilli gasseri EB01 EcoVagBifodan (Denmark)

Slide22

4.Improving cultural and social well being

Fermantation can imrove the flavor and apperance of food.For ex: Furundu, a meat substitute, is traditionally prepared by cooking the karkade

(Hibiscus sabdariffa L.) seed and then fermenting it for 9 days. Fermented vegetables such as pickles,gundruk and sauerkraut are used to as condiments to enhance

theoverall flavor of the meal.Gundruk is fermented green vegetables like mustard, turnip, radish, cauliflower leaves or any green leaves like spinach (

Saag). It is one of the famou s foods in Nepal.

Slide23

5.Malolactic fermentation

Malolactic fermentation (also known as malolactic conversion or MLF) is a process in winemaking in which tart-tasting malic acid, naturally present in grape must, is converted to softer-tasting lactic acid

.LAB can decarboxylate L-malic acid to produce L-Lactate in malolactic fermentation. This fermentation associates with wines. It promotes to provide bacteriological stability to the bottled product. It may also improve body and flavor.

Slide24

Main Fermented

Foods produced around worldFermented foods and beverages are part of nutrition culture o

f societies in all over the wMilk (kurut, kefir, koumiss), cereals (tarhana, boza, mahewu, idli,dosa), meat

(sucuk, pastırma), fish (fish sauce), soy (soy souce, natto, C), vegetables and fruits(kimchi, sauerkraut, gundruk, sunki

) based fermented products are produced in both around the worldand our country.

Slide25

mahewu

is a traditional Southern African non-alcoholic drink made from maize meal. Home production is still widely practiced, but the drink is also available at many supermarkets, being produced at factories.

Slide26

idli

Idli is a very popular fermented breakfast food consumed in the Indian subcontinent made mainly of rice and black gram.

rice

Black gram

idli

Slide27

Dosa

Dosa—a rice-based crepe from fermented batter of rice and lentil—were highly popular, and also consumed as breakfast food

rice

Black

lentil

dosa

Slide28

Tempeh

is a traditional soy product originating from

Indonesia. It is made by a natural culturing and controlled fermentation process that binds soybeans

into a cake form.

Slide29

Sunki

Sunki is a non-salted and fermented vegetable product prepared from the leaves of "Otaki-turnip" in Kiso district, Nagano prefecture, Japan. he Otaki-turnip is boiled, inoculated with "Zumi" (a wild small apple) dried

Sunki from the previous year and allowed to ferment for one to two months. Sunki is produced under low temperature (in winter season).