Applications of Food Biotechnology
Siti Nur Jannah
Introduction
• Genetically modified food is synthesized using biotechnological tools.
• Modern Biotechnology is helpful in enhancing taste, yield, shell life and nutritive values.
• This is also useful in food processing (fermentation and enzyme involving processes).
• So Biotechnology is beneficial in erasing hunger,
malnutrition and diseases from developing countries and
third word.
Beneficial microorganisms are used in foods in several ways
1 2 3 4
✓ Actively growing microbial cells (the conversion of milk to yogurt by bacteria)
➢ nongrowing
microbial cells (some bacteria are used to increase shelf life of refrigerated raw milk or raw meat)
➢ metabolic by-products (such as lactic acid, acetic acid, some
essential amino acids, and bacteriocins)
➢ cellular components of microorganisms (single-cell proteins (SCPs), dextran, cellulose, and many enzymes).
Historical Developments
• Historically, Solid-state (substrate) fermentation (SSF) processes have been used since ancient
time for food applications.
• SSF dates back to 6000 BC when Babylonians made beer from natural yeast.
• Egyptians used this technique for bread making in 2600 BC, using brewer’s yeast.
• Cheese making with Penicillium roquefortii was
recorded in Asia before the birth of Christ. Koji
processing reported to be migrated from China
to Japan in the seventh century.
• Fermented foods can be stored for longer
periods and used for food supply during the off season.
• Fermentation also contributes to the
digestibility and enhances the nutritional value of the product.
• It can also increase fibre digestibility.
• However, there are chances of accidental contamination of SSF food products by
mycotoxins, which are a class of unwanted
compounds and could be accidentally present or
produced in SSF products.
• Miso, tempeh, tamari sauce, soy sauce, ang-kak, natto, tou-fu-ru, and minchin are some of the
other ancient fermented foods known for centuries, which are prepared through SSF.
• Tempeh and tamari sauce are soybean products, the former is an Indonesian food fermented by Rhizopus species and the latter is a Japanese food produced by using Aspergillus tamari.
• Soy sauce, a brown, salty, tangy sauce, is
obtained from a sterile mixture of wheat bran and soybean flour, fermented initially by lactic acid bacteria, followed by alcoholic
fermentation and ripening.
Fermentation
• Fermentation in food is the process that produces alcoholic beverages or acidic products or CO2 for some products by the activity of microorganisms
• a process in which raw materials are converted to fermented foods by the growth and metabolic activities of the desirable microorganisms.
• For a cell, fermentation is a way of getting energy without using oxygen
• The microorganisms utilize some components present in the raw materials as substrates to generate energy and cellular components, to increase in population,and to produce many usable by-products (also called end products) that are
excreted in the environment.
• General properties of fermented foods : enhanced preservation, nutritional value, fuctionality,
organoleptic properties, unique, increased economic
value
• Food biotechnology industry now a days is the greatest industry in the world and with the help of food biotechnology
• We improve taste,consistency,colour, nutrition,safety and preservation of food.
• Development in food preservation methods have made many of seasonal foods to be available rounds the year.
• Fruits,vegetables,meats,cereals etc requires some degree of
processing and relatively bulky raw agricultural food materials are transformed into stable,convenient and palatable foods and
beverages…
Lactic acid bacteria (LAB)
• A clade of Gram-positive, acid-tolerant, generally non-sporulating rods or cocci Usually found in decomposing plants and lactic products,
produce lactic acid as the major metabolic end-product of carbohydrate fermentation.
• This trait has, links LAB with food fermentations, as acidification inhibits the growth of spoilage agents.
• Bacteriocins are produced by several LAB strains and provide an additional hurdle for spoilage and pathogenic microorganisms.
• Generally recognized as safe (GRAS) status, due to their ubiquitous appearance in food and their contribution to the healthy microflora of human mucosal surfaces.
Lactic acid bacteria Common genera
• Lactobacillus, Leuconostoc, Pediococcus, Lactococcus,
Streptococcus, Aerococcus, Carnobacterium, Enterococcus,
Oenococcus, Sporolactobacillus, Tetragenococcus, Vagococcus, Weisella
Yogurt
• Fermentation of milk by Lactobacillus bulgaricus and Streptococcus thermophilus at 40-45 ◦C.
• After 4 hrs, sufficient acidity is generated, good to enhance shelf life. Flavour is imparted by accumulation of lactic acid and
acetaldehyde produced by L. bulgaricus.
• Commercially produced from pasteurized skimmed milk with added milk powder.
Cheese
• the milk protein Cheese is a generic term for a diverse group of milk-based food products.
• Cheese is produced throughout the world in wide-ranging flavors, textures, and forms.
• Obtained by milk fermentation Coagulated mixture of proteins including casein Enzymetic process (rennin)
• Cheese Whey Lactic bacteria are used Renin may be obtained From the calf stomach or Produced by microorganisms
Fermented Meats
• A delicacy in some middle-east countries.
• Fermentation of meat is carried out during curing by lactic bacteria and Pedicoccus cerevisiae.
• Several types of salamis and sausages are produced by fermentation
• Gives flavour Preserves food
Leavening bread
• The dough is fermented in the presence of sugar and yeast.
Saccharomyces cerevisiae, the Baker’s yeast is mostly used in leavening process.
• Production of Baker’s yeast Normally grown at 30◦C on molasses which is Having low conc. of sugar (0.5-1.5%) Rich in mineral salts pH about 4.5
• During fermentation, sugar content of molasses is meticulously controlled as higher conc. is deterrent to respiratory enzymes.
Yeast is collected through centrifugation.
Alcoholic beverage:
• They are found in different forms in different regions.. for example in cooler regions of Europe, Poland and Russia production and consumption of beer from barley is more common ;whereas, in warm countries, like Spain, Greece, Italy and France, wines derived from grapes are more common.
• The starting material normally contains either:
• Sugary: Sugary materials,like Apple juice (to get cider), grape, pear, Palmyra juices (to get toddy in India and south Asia), molasses (to get distilled rum,and gins is obtained from distillation of rum in the
presence of juniper berries), honey, sweet potato, etc or Starchy:
• Starchy materials like barley, rye, rice, sorghum, beet root, potato,
etc..and the starchy materials need to be hydrolyzed to simple sugars by some saccharifying agents, like grain malt, aspergillus oryzea, rhizopus, mucor, baccillus, etc..
Wine
• Wine means fermented grape juice and histrorically, it is the Middle Eastern and European drink. France, Italy and Germany are its major producers.
• It is obtained from fruit juices mainly from wine grapes,Vitis vinifera which contains 15-25% sugar.
• Some of important types of wines:
• Red Wine is formed from the fermentation of crushed whole black grapes (with skin); White wine is produced from the black grapes without skin or green grapes; Rose Wine is produced from black grapes with some skin; Dry Wine is obtained from complete fermentation of sugar; Sweet Wine retains some sugar.
• Sparkling Wine is obtained from secondary fermentation of wine containing 1% fermentable sugar and yeast in setteled bottles.
• The CO2 produced due to fermentation of added sugar by yeast, get dissolved under pressure in the bottle.After
fermentation the water in neck of bottle is frozen to form an ice plug.Thus the CO2 is not allowed to escap from
bottle.
• Fortified Wines In which additional alcohol is added after the fermentation thus raising the alcohol content to about 20% e.g, brandy.
Formation of Wine :
• first grapes are crushed and the juice thus obtained called must (containg fructose and glucose) is
sterilized by SO2 to control the natural
fermentation by contaminating yeast .Then it is inoculated with the desired strain of yeast and is subjected to fermentation of the simple sugars glucose ,fructose in tanks or bioreactors for a few days to 14 days (no saccrification is required).After fermentation it is stored for months or years
(aging) for chemical changes to improve the flavor, aroma and for clarification by settling of
impurities.The Alcoholic contents of wine ranges from 7-15%.Moderate wine consumption is
beneficial for Coronary Heart Diseases. Champagne and Brandy are obtained from distillation of wine
• Beer is the world's most widely consumed and probably the oldest alcoholic beverage.
• Third most popular drink overall.
• The production of beer is called brewing, which involves the fermentation of starches.
• Additional carbohydrate sources
BEER
Alcoholic Beverages
• Vinegar is an alcoholic liquid that has been allowed to sour. Used to flavor and preserve foods. Ingredient in salad dressings and marinades. Used as a cleaning agent.
• Two successive fermentations of grape juice, raisins or malt 1. S.
cerevisiae anerobically converts carbs to alcohol 2. Oxidative transformation of alcohol to acetic acid by Acetobacter and Gluconobacter.
• Starting material includes Citrus fruits Apple Pear Vegetables like potatoes Malted cereals Sugary syrups such as molasses, honey etc.
Coffee, Tea and Cocoa:
• Coffee, tea and cocoa are very popular nonalcoholic fermented beverages, and extensively consumed
throughout the world.
• When the tea leaves are crushed, the chemical
components of tea are released by enzymatic activity.
For coffee and cocoa, a natural fermentation process (by bacteria, yeast and fungi) on the pulp surrounding beans results in the development of flavour and aroma.
Production of Amino Acids
• Amino acids are consumed in a variety of markets. The largest by volume is the food flavoring industry.
• Monosodium Glutamate, alanine, aspartate, arginine are all used to improve the flavor of food. L-lysine is directly produced from carbs by using Corynebacterium glutamcum, an auxotroph MSG is produced by Arthrobacter, Corynebacterium and Brevibacterium
Single-cell protein (SCP)
• SCP refers to the dried microbial cells or total protein extracted from pure microbial cell culture (monoculture – Algae, bacteria, filamentous fungi, yeasts, etc…), which can be used as food
supplement to humans (Food Grade) or animals (Feed grade).
• SCP contains high protein content (60 – 80% of dry cell weight), fats, carbohydrates, nucleic acids, vitamins, and minerals. It is also rich in essential amino acids such as Lys and Met.
• The three main applications of SCP are its use as protein
supplements in human foods, as protein supplements for livestock feeding, and as functional ingredients in foods. In the first two
cases, emphasis must be laid on the nutritional properties of the biomass, whereas for functional applications, the functional
behavior of the biomass ingredients in the food products has greater importance.
• With all three, however, the product must be free of toxins or other undesirable metabolites, heavy metals, and pathogens; it must have acceptable sensory properties, and a low viable cell count.
FERMENTED FOODS INDUSTRY : PAST AND PRESENT
TRADITIONAL MODERN
✓ Small scale (craft industry)
✓ Non-sterile medium
✓ Manual
✓ Insensitive to time
✓ Exposure to contaminants
✓ Varying quality
✓ Safety a minor concern
➢ Large scale (in factories)
➢ Heat-treat medium
➢ Automated
➢ Time-sensitive
➢ Contaminants excluded
➢ Consistent quality
➢ Safety major concern
Biotechnology in Food Processing
Fermentation Enzym
✓ Different yeast strains are used to make breweries at commercial level.
✓ Genetic engineering has enabled us to make light wine.
✓ Yeast is genetically modified through foreign gene encoding glucoamylase.
✓ During process of fermentation yeast expresses glucoamylase that convert starch into glucose
➢ Enzymes are used in production and processing of food items specifically produced at industrial level
➢ These enzymes comprises of proteases and
carbohydrases. Genes for these enzymes have been cloned so as to get higher production in less time period.
These enzymes include rennin and α-amylase.
Catalase used in mayonnaise production and it removes hydrogen peroxide, Chymosin useful in cheese production as it coagulates milk, Glucose oxidase is used in baking as it stabilizes the dough, Protease used for meat
tenderization process, baking and dairy products
Biotechnology: Improving Food Nutrition
Proteins and essential amino acids: Vitamins and minerals:
More than half of worldwide
protein production is attained from plants but plant proteins lack some essential amino acids like lysine and sulphur containing amino acids. To overcome the deficiency of essential amino acids, different biotechnological molecular processes are used and given below
Rice is one of the foods used as staple food in many countries of world. But being deficient in Vitamin A, rice is not a perfect staple food. The first provitamin rich transgenic rice was produced by incorporating crtI
gene and psy gene from bacteria and daffodils.
Scientists are working on introduction of other
vitamins and macronutrients (iron, zinc etc.) genes in vitamin deficient food articles
Biotechnology: Enhancing Taste
• Biotechnology has allowed scientists to produce fruits with better taste.
• GM foods with better taste include seedless watermelon, tomato, eggplant, pepper and cherries etc.
• Elimination of seed from these food articles resulted in more soluble sugar content enhancing sweetness
• Fermentation pathways are modified using biotechnology to add aroma
Biosensor in food
• A biosensor can be defined as a quantitative or semi-quantitative analytical
instrumental technique containing a sensing element of biological origin, which is either integrated within or is in intimate contact with a physico-chemical
transducer.
• A chemical sensor is a device that transforms chemical information, ranging from the concentration of a specific sample component to total composition analysis, into an analytically useful signal.
• Chemical sensors usually contain two basic components connected in series: a chemical (molecular) recognition system (receptor) and a physicochemical transducer. Similarly, biosensors are chemical sensors in which the recognition system utilizes a biochemical mechanism interfacing the optoelectronic system.
A device that uses specific biochemical reactions mediated by isolated enzymes, immunosystems, tissues, organelles or whole cells to detect chemical
compounds usually by electrical, thermal or optical signals
Biosensors for pesticide monitoring in food and environmental samples
• A highly sensitive immuno-sensor system was developed for the
detection of ethyl and methyl parathions, 2,4-Dichlorophenoxyacetic acid and atrazine at picograms concentration (ppt) based on the
immuno-chemiluminescence principle. Antibodies against pesticides were raised in chicken (IgY) and rabbit (IgG). An economical IgY was produced for highly sensitive detection system based on immuno-
chemiluminescence biosensor (Chouhan et al. 2006). The high sensitivities of pesticides detection achieved in the project show promise of excellent applications of our immunosensors for field application.
Why genetically modify food?
Food biotechnology is and will continue to be an important area in science as the world’s human population continues to increase and the world’s
agricultural lands continue to decrease.
The following are reasons why
“we” genetically modify food.
1) Extended Shelf Life
• The first steps in genetic modification were for food producers to ensure larger
profits by keeping food fresher, longer.
• This allowed for further travel to and longer availability at markets, etc…
Extended Shelf Life Milk
Example: Long Shelf Tomatoes
These genetically modified
tomatoes promise less waste and higher profits.
Typically, tomatoes produce a protein that softens them after they have been picked.
Scientists can now introduce a gene into a tomato plant that blocks synthesis of the softening protein.
Without this protein, the genetically altered tomato softens more slowly than a
regular tomato, enabling farmers to harvest it at its most flavorful and nutritious vine-ripe stage.
2) Efficient Food Processing
• By genetically modifying food producing organisms, the wait time and quantity of certain food processing necessities are optimized.
• Again this is a money saver.
Although efficient, this type of food processing is not an example of
biotechnology.
Example: Rennin Production
The protein rennin is used to coagulate milk in the
production of cheese.
Rennin has traditionally been made in the stomachs of calves which is a costly process.
Now scientists can insert a copy of the rennin gene into bacteria and then use bacterial cultures to mass produce
rennin.
This saves time, money, space and animals.
Rennin in the top test tube… not there in the bottom one.
3) Better Nutrient Composition
Some plants, during
processing, lose some of the vital nutrients they once
possessed.
Others are grown in nutrient poor areas.
Both these problems can be solved by introducing genes into plants to increase the amount or potency of
nutrients.
“Biofortification”
Example: Golden Rice
Scientists have engineered "golden rice", which has received genes from a daffodil and a bacterium that enable it to make beta-
carotene.
This offers some promise in helping to correct a worldwide Vitamin A deficiency.
4) Efficient Drug Delivery
• Inserting genes into
plants/animals to produce
essential medicine or vaccines.
• “Biopharming”
Many Unpatented Examples
• A cow with the genetic equipment to make a vaccine in its milk could provide both nourishment and immunization to a whole
village of people now left unprotected because they lack food and medical help (in progress).
• Bananas and potatoes make hepatitis vaccines (done).
• Making AIDS drugs from tobacco leaves (done).
• Harvest vaccines by genetically altering hydroponically grown tomato plants to secrete protein through their root systems into the water (done).
Potential Problems???
• With every technology there is an associated risk involved.
• The following are some
examples of potential problems associated with food
biotechnology.
1) Creating “Superbugs”
Since many of the “vectors”
used to introduce genes to plants and animals are
bacteria and viruses, it is realistic to think there is a chance they could undergo a mutation and prove harmful or become recombinant like the H1N1 virus and thus more
virulent.
However, the bacteria and viruses used in these
procedures are usually non- pathogenic.
Viruses Bacteria
2) Negative Affects on Human Health
• Most of these food products undergo testing to see if any adverse health effects
occur.
• However, allergies were not thought of in one case
where a gene from a brazil nut was transferred to soy bean plants!
• Thankfully a food product was not pursued as someone came to their senses!
• Important to note that not all genes from a potential allergenic food will cause an allergy.
3) Ethics
How many human genes would an organism have to have
before you consider it human???
The following food types have a variety with human genes added: rice (immune system genes that prevent diarrhea), baby food (lactoferrin and
lysozyme) and any farm animal (Human growth hormone).
