Recent advancments in food and dairy microbiology

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Recent Advancements In Food And Dairy Microbiology
Much advancement is achieved in food and dairy microbiology. Some resent advancements are
discussed below.
Fermentation
Fermentation is one way microorganisms can change a food. Yeast, especially Saccharomyces
cerevisiae, is used to leaven bread, brew beer and make wine. Certain bacteria, including lactic
acid bacteria, are used to make yogurt, cheese, hot sauce, pickles, fermented sausages etc. A
common effect of these fermentations is that the food product is less hospitable to other
microorganisms, including pathogens and spoilage-causing microorganisms, thus extending the
food's shelf-life. Some cheese varieties also require molds to ripen and develop their
characteristic flavors.
Food safety
Food safety is a major focus of food microbiology. Pathogenic bacteria, viruses and toxins
produced by microorganisms are all possible contaminants of food. However, microorganisms
and their products can also be used to combat these pathogenic microbes. Probiotic bacteria,
including those that produce bacteriocins, can kill and inhibit pathogens. Alternatively, purified
bacteriocins such as nisin can be added directly to food products. Finally, bacteriophages, viruses
that only infect bacteria, can be used to kill bacterial pathogens. Thorough preparation of food,
including proper cooking, eliminates most bacteria and viruses.
Microbial biopolymers
Several microbially-produced polymers are used in the food industry.
Alginate
Alginates can be used as thickening agents. Although listed here under the category 'Microbial
polysaccharides', commercial alginates are currently only produced by extraction from brown
seaweeds such as Laminaria hyperborea or L. japonica.
Cellulose
Cellulose is a simple polysaccharide, in that it consists only of one type of sugar (glucose), and
the units are linearly arranged and linked together by β-1,4 linkages only. The mechanism of
biosynthesis is, however, rather complex, partly because in native celluloses, the chains are
organized as highly ordered water-insoluble fibers. Currently, the key genes involved in cellulose
biosynthesis and regulation are known in a number of bacteria, but many details of the
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biochemistry of its biosynthesis are still not clear. In spite of the enormous abundance of
cellulose in plants, bacterial celluloses are being investigated for industrial exploitations.
Poly-γ-glutamic acid
Poly-γ-glutamic acid (γ-PGA) produced by various strains of Bacillus has potential applications
as a thickener in the food industry.
Biofertilizers
A biofertilizer (also bio-fertilizer) is a substance which contains living microorganisms which,
when applied to seed, plant surfaces, or soil, colonizes the rhizosphere or the interior of the plant
and promotes growth by increasing the supply or availability of primary nutrients to the host
plant.[1]
Bio-fertilizers add nutrients through the natural processes of nitrogen fixation,
solubilizing phosphorus, and stimulating plant growth through the synthesis of growth-
promoting substances. Bio-fertilizers can be expected to reduce the use of chemical fertilizers
and pesticides. The microorganisms in bio-fertilizers restore the soil's natural nutrient cycle and
build soil organic matter. Through the use of bio-fertilizers, healthy plants can be grown, while
enhancing the sustainability and the health of the soil. Since they play several roles, a preferred
scientific term for such beneficial bacteria is "plant-growth promoting rhizobacteria" (PGPR).
Therefore, they are extremely advantageous in enriching soil fertility and fulfilling plant nutrient
requirements by supplying the organic nutrients through microorganism and their byproducts.
Hence, bio-fertilizers do not contain any chemicals which are harmful to the living soil.
Bio-fertilizers eco friendly organic agro-input and more cost-effective than chemical fertilizers.
Bio-fertilizers such as Rhizobium, Azotobacter, Azospirillum and blue green algae (BGA) have
been in use a long time. Rhizobiuminoculant is used for leguminous crops. Azotobacter can be
used with crops like wheat, maize, mustard, cotton, potato and other vegetable crops.
Azospirillum inoculations are recommended mainly for sorghum, millets, maize, sugarcane and
wheat. Blue green algae belonging to a general cyanobacteria genus, Nostoc or Anabaena or
Tolypothrix or Aulosira, fix atmospheric nitrogen and are used as inoculations for paddy crop
grown both under upland and low-land conditions. Anabaena in association with water fern
Azolla contributes nitrogen up to 60 kg/ha/season and also enriches soils with organic matter.
Other types of bacteria, so-called phosphate-solubilizing bacteria, such as Pantoea agglomerans
strain P5 or Pseudomonas putida strain P13, are able to solubilize the insoluble phosphate from
organic and inorganic phosphate sources.
Biopesticides
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Biopesticides, a contraction of 'biological pesticides', include several types of pest management
intervention: through predatory, parasitic, or chemical relationships. The term has been
associated historically with biological control - and by implication - the manipulation of living
organisms.
Examples: Bacillus thuringiensis, a bacterial disease of Lepidoptera, Coleoptera and Diptera, is
a well-known insecticide example. Because it has little effect on other organisms, it is considered
more environmentally friendly than synthetic pesticides. The toxin from B. thuringiensis (Bt
toxin) has been incorporated directly into plants through the use of genetic engineering.
Plant disease control agents: include Trichoderma spp. and Ampelomyces quisqualis (a hyper-
parasite of grape powdery mildew); Bacillus subtilis is also used to control plant pathogens.
Beneficial nematodes attacking insect (e.g. Steinernema feltiae) or slug (e.g. Phasmarhabditis
hermaphrodita) pests
Weeds and rodents have also been controlled with microbial agents.
Biopesticides are typically microbial biological pest control agents that are applied in a manner
similar to chemical pesticides. In order to implement these environmentally friendly pest control
agents effectively, it can be important to pay attention to the way they are formulated[5]
and
applied.
Veterinary microbiology
The role of microbes in veterinary medicine development is apparent e.g. bird flu vaccines.
Preservation methods: like gamma radiations for meat, freezing, refrigeration,
Plant and animal tissue culturing: For new pharmaceutical products, production of disease
resistant plants and animals etc
Canning: used for dinks and food preservation and long shelf-life
Sterilization of Milk through Pasteurization
New milk products like chesses etc
Dried milk
Milk along with supplements like vitamins etc
Sterile packing
Amjad Khan Afridi 10th
May, 2017