Dr. D. K. AntalaKhira Samir Mulchand2021-06-042021-06-042019-08https://krishikosh.egranth.ac.in/handle/1/5810169547India is the one of the largest producer of banana (Musa paradisiac L.) in the world. Banana is considered a common man’s fruit and is rightly called the dessert fruit. Banana, being a tropical fruit, has a very short shelf life. Foam mat drying allows dehydration of heat sensitive, high sugar content and viscous food like banana which is difficult to dry. The foam mat dried products are cost effective and highly stable against deteriorative microbial, chemical and biochemical reactions. The banana powder can be used as food ingredient and natural flavouring agent in other products during off season. This reduces the glut in the market and farmers fetch remunerative price during harvesting season in the domestic market. High yielding banana variety of Grand Naine which is most commonly grown in Saurashtra region was selected for the experiment. The ripened banana (stage-5) was procured from the local market of Junagadh, Gujarat. The experiment was carried out in the Department of Processing and Food Engineering, College of Agricultural Engineering and Technology, Junagadh Agricultural University, Junagadh during the year 2018-19. Fruits having 15 ± 1 °Brix TSS were cut into small slices of 3-5 mm and dipped in 1% (w/w) solution of sodium meta bisulphite for 2 min and then rinsed in water for 30 s. Blending and whipping of pulp was carried out with a portable hand blender for proper mixing of air with the pulp. The effect of three foaming parameters viz., foaming agent (2.5, 4.53, 7.5, 10.47 and 12.5%), foaming stabilizer (0.1, 0.18, 0.3, 0.42 and 0.5%) and whipping time (5, 9, 15, 21 and 25 min) were optimized on foam expansion, foam stability and foam density of banana pulp using response surface methodology. Whey protein isolate was used as foaming agent and methyl cellulose was used as foaming stabilizer. The optimum treatment conditions were found to be 5.35% foaming agent, 0.45% foaming stabilizer and 9.43 min whipping time with foam expansion of 138.95%, foam stability of 96.33% and foam density of 0.43 g/cc. The performance of this model was also verified by conducting an experiment at the optimized condition. It could reveal that the experimental value was very close to the predicted value that confirmed the validation of derived model. Optimized parameters for foaming properties of banana pulp were selected for further drying of foamed banana. Drying of foamed banana pulp was carried out at four ii levels of drying temperature (55, 60, 65 and 70 °C) and three levels of foam thickness (2, 4 and 6 mm) in a tray dryer. After drying, dried sample was scrapped, grinded and sieved through mesh no. 35 sieve. Drying characteristics viz., drying time, drying rate and moisture ratio of foam mat drying of banana pulp were evaluated. Maximum drying time (300 min) was observed at 55 °C drying temperature and 6 mm foam thickness while minimum drying time (120 min) was observed at 70 °C drying temperature and 2 mm thickness. Drying time for drying temperature 60 °C and 2 mm foam thickness was recorded 180 min. Maximum drying rate (0.310 g water/g dry matter/min) was found for 70 °C for drying temperature for 2 mm foam thickness and minimum drying rate (0.113 g water/g dry matter/min) was recorded for 55 °C drying temperature for 6 mm foamed thickness of banana pulp. There was rapid decrease in moisture ratio with faster rate at initial stage of 50 to 70 min of drying in all cases, however in later stage of drying, the decrease in moisture ratio was at slower rate. Quality parameters viz., physical properties, biochemical properties, functional properties and sensory characteristics of banana powder were carried out after drying of banana foam. Maximum recovery (37.86%), total sugars (39.25%), non-reducing sugar (39.14%), ascorbic acid (0.89 mg/100 g), pH (4.53), water solubility index (66.10%), water absorption index (408.48%) and minimum reducing sugar (0.11%), titratable acidity (0.35%) of banana powder was found for treatment combination T1t1 (55 °C and 2 mm) and it was found at par with treatment combination T2t1 (60 °C and 2 mm) for most of the case. Maximum sensory score (8.2) in term of appearance, texture, flavour, taste and overall acceptability of foam mat dried banana powder was observed in treatment combination T2t1 i.e., 60 °C drying temperature and 2 mm foam thickness. Longer drying time (300 min), more moisture content (5.38) and low sensory score (7.6) was found for treatment combination T1t1 (55 °C and 2 mm) while moderate drying time (150 min), physico-chemical properties and maximum sensory score (8.2) was found for treatment combination T2t1 (60 °C and 2 mm). From the above study, it could be concluded that treatment combination T2t1, i.e., 60 °C drying temperature and 2 mm foam thickness was found to be best among all the treatments considering overall quality and drying time for preparation of banana powderEnglishThesis