This document discusses probiotics and fermented foods. It defines probiotics as live microorganisms that are similar to beneficial microorganisms found in the human gut. Probiotics must be able to survive passage through the digestive system, attach to intestinal cells, and exert beneficial health effects. Fermented foods are produced through the metabolic process of microbes like bacteria and yeast, through processes like lactic acid fermentation. Fermented foods can provide health benefits like improved nutrient absorption and promotion of a healthy gut microbiome. Examples of fermented foods mentioned include yogurt, sauerkraut, and kefir.
2. Probiotics
Probiotics are live microorganisms that are
similar to beneficial microorganisms found in the
human gut. They are also called “friendly
bacteria” or “good bacteria.
Latin word pro means "for"and the Greek letter
bios means "life".
The term contrasts with the term antibiotic
3. Definition
Experts have debated how
to define probiotics
One widely used definition,
developed by the World
Health(WHO)
“Live microorganisms,
which, when administered
in adequate amounts, confer
a health benefit on the host ”
4. Properties of Effective Probiotics
Non pathogenic and non toxic
Able to survive the passage through the digestive system.
Able to attach to the intestinal epithelia and colonise.
Able to maintain good viability.
Able to utilise the nutrients and substrates in a normal diet.
Capable of exerting a benificial effect on the host.
Stability of desired characteristics during processing, storage and
transportation.
Anti-inflammatory, antimutagenic, immunostimulatory.
6. Advantages
Increased nutritional value
Promotion recovery of diarrhea
Inhibition of pathogen growth and translocation
Produce vitamins (especially Vitamin B and vitamin K)
Enhancing specific and nonspecific immune response
Stimulation of gastrointestinal immunity
Decreasing prevalence of allergy in susceptible
individuals
7. Isolation and identification of
Lactobacillus
Collection of Samples:- fecal ,milk,yoghurt
samples
Media :-MRS
Identification:
Gram Staining,
catalase test
8. How is yogurt different from curd?
1.Curd
( i) Obtained by coagulation of milk by harmless
lactic acid bacteria like Lactobacillus Lactococcus
lactis.
(ii) It may contain a wide variety of bacteria, which
are not defined qualitatively/quantitatively
2.Yoghurt
( i) Obtained by lactic acid fermentation of milk by
Lactobacillus bulgaricus and Streptococcus
thermophillus
10. Yakult is a probiotic dairy product made
by fermenting a mixture of skimmed milk with a
special strain of the bacterium Lactobacillus
casei Shirota.
It was created by Japanese scientist Minoru
Shirota , who graduated from the Medical School
of Kyoto University in 1930
12. Fermentation: Defined
Transformation of food using bacteria, fungi, or
the enzymes they produce via anaerobic
metabolism to produce acid or alcohol
Examples of fermented foods: Sauerkraut, yogurt,
kombucha, miso, kefir, tempeh, kim-chi
But also bread, cheese, beer, wine
13. Science of Fermented Foods
Lacto-fermentation most common
Lactobacillus bacteria
Sugar Lactic acid
Acetic acid fermentation
Acetobacter bacteria
Ethanol Vinegar
Alcohol fermentation
Strains of yeast
Juice Ethanol
14. Science of Fermented Foods
Lacto-fermentation:
Create a selective environment lactic acid bacteria to thrive; molds &
other oxygen-dependent organisms unable to grow
Lacto bacteria anaerobic, salt tolerant
Wild fermentation
Veggies naturally covered in bacteria, molds, and yeasts
Cultured fermentation
Whey
Dried starter cultures
Brine from a previous ferment
Kombucha SCOBY
Kefir grains
15. Health Benefits of Fermented Foods
Breakdown of nutrients
Grain, milk intolerances – many people able to tolerate
fermented versions
Breakdown of phytic acid
Nutrient enhancement & production of micronutrients
Example: B vitamins, vitamin K2
Iron, Mg, Ca, Zn more bioavailable
Can detoxify certain foods
Example: Cassava tubers, some exotic nuts
Live, lactic acid bacteria cultures
Promotes healthy microbiome
