Patel et.al.
Guava ( Psidium guajava L.) is one of the most well
India. Five years old bearing plant of eleven
known edible tree fruits grown widely in more
genotypes of guava viz., RCG-1, RCG-2, RCG-3,
than sixty countries throughout the tropical and
RCG-11, RCGH-1, RCGH-4, RCGH-7, Allahabad
subtropical regions of the world. The fruits are
Safeda, Lucknow-49, Lalit and Sangam were
delicious, rich in vitamin ‘C’, pectin and minerals
selected for this study. The experiment was laid out
like calcium, phosphorus and iron. Guava fruits are
in randomized block design with three replications
used as fresh as well as for making jam, jelly, nectar,
and three plants per replication. One hundred fruits
paste etc. (Patra et al. , 2004). Furthermore, high
just after fruit set were tagged on each of the three
concentrations of pectin in guava fruit may play a
selected plant in each replication of all the genotypes.
significant role in the reduction of cholesterol and
Ten randomly selected fruit amongst tagged fruits
thereby decrease the risk of cardiovascular disease.
from all directions of each plant and genotype at 30,
Considered as “poor man’s apple”, the guava truly
60, 90, 105, 120 and 127 days after fruit set (DAFS)
happens to be the fruit for masses in terms of its
were harvested for study the fruit size, weight and
availability in the market and accessibility to the
biochemical parameters.
poor (Jayachandran et al. , 2005). Since, guava plants
bears flowering and fruiting once in a year during
Physical changes
April-May and October-November respectively in
Fruit length and diameter were measured from
this region as compared to twice or thrice crops per
randomly selected fruit during study. The length from
year in other parts of the India. Standardization of the
base of fruit to the base of the calyx and diameter
external features, physical characters and chemical
at the maximum bulge of fruit from both side were
composition of commercially important guava
measured with help of ‘digital vernier caliper’ and
cultivar is therefore needed. It is known that the
mean values of length and diameter were presented
quality and storage life of fruits depend on various
in cm. The weight of the fruits was calculated on the
physiological and biological changes, which occur
basis of 10 representative fruits and the mean was
during fruit growth, development and maturity
expressed in gram.
(Harding and Hatoon 1967). Harvesting at correct
stage of maturity has great bearing on the quality of
Biochemical changes
fruits. The information pertaining to the physical and
biochemical changes in guava at different stages of
Biochemical parameters i.e., total soluble solids
fruit growth and maturity is very scanty under mid
(TSS), acidity and TSS: acid ratio of guava fruits were
hillsofnortheasternregionofIndia.Suchinformation
estimatedat30,60,90,105,120and127daysafterfruit
are required because physico-chemical changes
set (DAFS) for all genotypes. The pulp was extracted
during maturity can be used as important criteria for
from fruits by crushing and squeezing through
determining the optimum stage of fruit harvesting
muslin cloth. The total soluble solids (TSS) of the
for better quality and extended shelf life. Therefore,
pulp were determined by placing the small quantity
keeping these facts in view a comprehensive study
of pulp on the prism of digital refractometer. Total
was carried out on various physical and biochemical
titratable acidity was determined by dissolving a
changes at different stages of fruit maturity to
known weight of pulp in a known volume of distilled
determine the appropriate maturity standards so as
water. The aliquot was titrated against 0.1 N sodium
to harvest the fruits in appropriate time for better
hydroxide using phenolphthalein as indicator. The
quality and desirable shelf life.
acidity was recorded in terms of percent citric acid
on fresh weight basis (AOAC 2000. The TSS: acidity
Materials and Methods
ratio was calculated by dividing the value of TSS by
that of titratable acidity.
An experiment was conducted at ICAR Research
Complex for NEH Region, Umiam, Meghalaya,
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