PhD

The investigation entitled “Profiling bioactive compounds and nutrients in
Jackfruit (Artocarpus heterophyllus Lam.) and developing a jackfruit based
textured vegetable protein‟‟, was carried out at College of Agriculture, Vellayani,
Thiruvananthapuram during the period of 2015-2018. The objectives of the study
were to ascertain the bioactive compounds and nutrients present in different
jackfruit types. The study also envisaged the improvement of digestive quality of
jackfruit through reduction of oligosaccharides and developing a jackfruit based
textured vegetable protein. The study was conducted in three experiments; viz.
analysis of nutrient and chemical profile along with antioxidant activity of the
selected types of jackfruit; analysis of measures for reducing antinutrients in raw
jackfruit and development of raw jackfruit based textured vegetable protein.
For the component wise analysis, five types of jackfruits viz Muttom
varikka, Then varikka, Sindoor, Chempikalom varikka and Local cv Koozha were
selected; their raw and ripe stages as well as both bulbs and seeds were analysed
separately. Analysis of proximate composition, vitamins, minerals, bioactive
compounds, antinutrients and antioxidant activity were covered in the first
experiment. The results showed that nutrient wise, raw seeds of Chempikalom and
ripe bulbs of Sindoor scored higher than the rest of treatments while with respect
to antioxidant activity, ripe seeds of Koozha were better than other treatments.
The profiling of nutrients and bioactive compounds in the each part of the
experiment is an eye opener on specific features of the common jackfruit type that
can be exploited according to varying needs.
The delicacy factor for non acceptability of jackfruit, despite its useful
composition is that, it has a flatulence factor. This study has thrown light in to the
measures to reduce these causative factors. For this purpose in the second part of
the experiment, one treatment is with enzyme α galactosidase and another
treatment with Saccharomyces cerevisiae was carried out on milled raw jackfruit
bulbs and seeds of cv koozha to reduce the level of anti nutrients. Enzyme α
galactosidase was premixed with the dry flour of jackfruit seed and jackfruit bulb
separately in the ratio 1:100 and the moisture level was varied from 25 – 200%
(dough to batter stage). The hydrolysis was carried out for 90 minutes in both
jackfruit bulb flour and seed flour. The products were evaluated for the
breakdown of oligosaccharides (Raffinose) using HPTLC method. The results
showed that the level of Raffinose after treatment with bulb flour and seed flour
was seen to decrease with increase in moisture content (25-100%). Thereafter the
content slightly staggered and then reduced (125%, 150%, 175%, 200%).
However the level of oligosaccharide decreased in comparison to levels in control
(0.97 μg g-1).
When flours were to be made into batter and subjected to fermentation with
Saccharomyces cerevisiae @ 5g/kg for 6 hrs, 8 hrs and 12 hrs and analyzed
through HPTLC assay; raffinose content in jackfruit bulb flour reduced from 0.75
μg g-1 to 0.63 μg g-1, 0.58 μg g-1 and 0.74 μg g-1 after 6, 8 and 12 hours
respectively. Raffinose content in jackfruit seed flour reduced from 1.28 μg g-1 to
0.42 μg g-1, 0.31 μg g-1 and 0.62 μg g-1 respectively after 6, 8 and 12 hours of
fermentation. Considering the reduction of raffinose content and sensory
evaluation of the treated flour, eight hour fermentation (F2) was selected as the
best treatment.
The demand for convenience foods among the literate consumers is on the
rise around the globe.
It has been argued that convenience is a barrier to
achieving proper nutrition using adequate servings. In order to incorporate the
fruit based nutritional benefits, it has become important to develop newer and
novel foods that could reach the consumers‟ acceptance. With this background an
attempt was visualized to develop jackfruit based textured vegetable protein
(TVP) to make jackfruit more popular among the health conscious people.
In the third experiment, Jackfruit based TVP was formulated by using the
ingredients - jackfruit bulb flour and seed flour along with gluten, yeast and soya
flour to form chunks using standardized methods. Totally eleven combinations of
TVP were worked out. All the eleven treatments were cooked and evaluated by a
panel of ten members. Based on the sensory attributes such as appearance, colour,
flavour, texture, taste and overall acceptability, the highest score was obtained for
T7 which was followed by T8 and these two treatments were seen to be on par. The
lowest score was obtained by treatment T4; T7 was taken up for quality analysis, it
had a protein content of 61.50g, carbohydrate content of 34.97g and lesser
cooking time (7.33 minutes). The physico chemical and textural qualities were on
par with soyachunks available in the market. Processed TVP showed good storage
stability up to three months. The third part of the study concluded with a positive
note on scope of commercializing this jackfruit based protein concentrate. The
product is both novel and healthy, raising its popularity for sailing up.
Thus, the study finds that there is variation in jackfruit types with respect
to nutrients, chemical and bioactive compounds. The efficacy of enzyme α
galactosidase and Saccharomyces cerevisiae to reduce oligosaccharide levels in
jackfruit flour is feasible. With high acceptable food like meat analogue was also
standardized based on jackfruit flours, which can be recommended for
commercialization.