Innovation in Inversion
S. Ghosh
Sugar is the most popular sweetener in the market. It
also possesses preservative, bulking, flavour enhancing
and texturing properties. The major reason for its popularity
are its ready availability, low cost, simplicity of production,
purity and long history of usage. If hydrolysed, it produces
invert syrup which manifests the above properties by many
folds.
Innovation is the key to success. Innovation needs to
be persuaded vigorously for the upgradation of technology
so that transformation in product quality and betterment
of life are achieved. A breakthrough innovation has been
achieved in the field of sweetener through biotechnological
production of invert sugar (IS). A radical change in the
quality of food and pharmaceutical products has been achieved
by replacing sugar with invert sugar. The technology has
revolutionised the market in such a way that new industrial
units are being set up to meet the diversified application
of invert sugar. R and B activities are also being carried
out.
Sugar is the most popular sweetener in the market. It also
possesses preservative, bulking, flavour enhancing and texturing
properties. The major reasons for its popularity are its
ready availability, low cost, simplicity of production,
purity and long history of usage. If hydrolysed, it produces
invert syrup which manifests the above properties by many
folds. Although, this information was known, no industrial
unit for IS production was started in the country due to
the absence of proper technology.
The old age method of acid inversion was the main tool
for IS and few actual users adopted this technique for
their requirement. This old age method is crude, results
non uniform products including formation of highly neuro
toxic hydroxy methyl furfural (HMF) and furfural.
The above crude acid hydrolysis can be improvised by
ion exchange resin. The uniform product quality is obtained
by adopting this method. Most of the manufacturers in
the world use the resin technology for IS production.
However, the main constraints of the process are operational
difficulties, above 45% sugar solution leading to blockage
of flow, high cost of resin, carbonisation, high degree
of effluent generation and formation of HMF.
The said coversion can also be achieved by enzymatic
action of invertase on sugar. Enzyme being target oriented
and mild in nature, does conversion with almost same percentage
efficiency without any byproducts formation. However,
for commercial success of the process, it is necessary
to immobilise a cheap source of invertase for its repeated
use and by utilising concentrated sucrose solution to
avoid upstream and down stream processing.
A number of attempts have been made to produce IS using
immobilised enzyme route. Most of the reported work failed
to see the ray of light of commercialisation for a number
of reasons particularly the absence of cheap right quality
food grade, immobilised system having high biocatalytic
activity and stability under practical operating conditions.
A commercially viable technology has been developed by
Food Technology Department of Bhabha Atomic Research Centre
to produce concentrated IS by a single step biocatalytic
process from concentrated aqueous solution of sucrose.
The substrate sucrose is passed through bioreactors containing
immobilized invertase. Yeast cells (S. cerevisiae) are
used as source of enzyme invertase, tailor made to obtain
the maximum biocatalytic activity of the enzyme and then
immobilized in an inexpansive inorganic matrix. The matrix
used is very cheap, easily available, inert, has high
mechanical strength, density and possess high thermal
and dimensional stability. The matrix is resistant to
microbial attack and nontoxic. The bioreactor once packed
can be used continuously for several months (6-8 months).
The product conforms to the BP standards and is absolutely
free from HMF and thus absolutely safe for use. The process
is virtually maintenance free and simple in operation.
It does not create any problem of pollution or effluents
and absolutely free from hazards.
The process was scaled up from bench scale level of 3
Kg/day to 500 Kg/day commercial plant leading to successful
scale up to 10 MT/day. A number of industrial units are
operating based on the technology. The product finds numerous
applications. The process is first of its kind in the
world commercialised for the production of invert sugar
based on whole cell immobilisation of yeast cells.
IS is 1.3 times sweeter than sugar and, therefore the
quantity used for sweetening any item is greatly reduced.
It tastes like honey and therefore can be used as a substitute
for honey. As it is available in a ready-to-use liquid
form, the problem of storing is minimised. It is free
from dental carioneity (commonly known as dental caries)
because of its unique property of not reacting with body
calcium, restricting the formation of dental caries. It
is a natural preservative, and has a longer shelf life.
It does not produce off-odour or off-taste when stored
for a long period of time and used in higher concentration.
It does not crystallise at high concentration and lower
temperatures, thereby minimising crystal formation in
ice-cream. It caramelises at lower temperature, thereby
reducing the baking temperature from 350 degrees to almost
200 degrees, and giving a rapid crust colour. It assimilates
faster in the stomach as compared to ordinary sugar. It
has a higher degree of solubility than sugar. It has higher
osmotic pressure than sugar. It maintains the calcium
balance in the body. IS is better than other sweeteners
that are often used, like saccharine, cyclamate and aspartame
because of the quality of sweetness and also because it
does not produce off-flavour at high usage levels. Its
use leads to formation of spongier cakes and ice-cream
devoid of crystals, crispier and evenly baked biscuits
without cracks, caramalisation at a lower temperature
and therefore, reduced time taken to bake cakes. IS is
India's answer to Europe's High Fructose Corn Syrup (HFCS),
a substitute for sugar. IS is finding new application
in the fields of tobacco, face cream, shoe polish etc.
Initial market data shows that there is a tremendous
growth potential of the product particularly in view of
the changed economic, scenario of our country. Indian
manufacturers can compete in international market by adopting
the technology invented in the country (single step) which
is superior and cheap to multi steps HFCS technology.
Moreover, in India, production of sugarcane, a plant that
fixes more carbon then corn is abundant and thus scope
for production of invert sugar through inversion is the
most appropriate choice of technology.
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Author is a faculty member of Food Technology Division,
Bhabha Atomic Research Centre, Mumbai
