Assam Agricultural University is the first institution of its kind in the whole of North-Eastern Region of India. The main goal of this institution is to produce globally competitive human resources in farm sectorand to carry out research in both conventional and frontier areas for production optimization as well as to disseminate the generated technologies as public good for benefitting the food growers/produces and traders involved in the sector while emphasizing on sustainability, equity and overall food security at household level.
Genesis of AAU -
The embryo of the agricultural research in the state of Assam was formed as early as 1897 with the establishment of the Upper Shillong Experimental Farm (now in Meghalaya) just after about a decade of creation of the agricultural department in 1882. However, the seeds of agricultural research in today’s Assam were sown in the dawn of the twentieth century with the establishment of two Rice Experimental Stations, one at Karimganj in Barak valley in 1913 and the other at Titabor in Brahmaputra valley in 1923. Subsequent to these research stations, a number of research stations were established to conduct research on important crops, more specifically, jute, pulses, oilseeds etc. The Assam Agricultural University was established on April 1, 1969 under The Assam Agricultural University Act, 1968’ with the mandate of imparting farm education, conduct research in agriculture and allied sciences and to effectively disseminate technologies so generated. Before establishment of the University, there were altogether 17 research schemes/projects in the state under the Department of Agriculture. By July 1973, all the research projects and 10 experimental farms were transferred by the Government of Assam to the AAU which already inherited the College of Agriculture and its farm at Barbheta, Jorhat and College of Veterinary Sciences at Khanapara, Guwahati.
Subsequently, College of Community Science at Jorhat (1969), College of Fisheries at Raha (1988), Biswanath College of Agriculture at Biswanath Chariali (1988) and Lakhimpur College of Veterinary Science at Joyhing, North Lakhimpur (1988) were established. Presently, the University has three more colleges under its jurisdiction, viz., Sarat Chandra Singha College of Agriculture, Chapar, College of Horticulture, Nalbari & College of Sericulture, Titabar. Similarly, few more regional research stations at Shillongani, Diphu, Gossaigaon, Lakhimpur; and commodity research stations at Kahikuchi, Buralikson, Tinsukia, Kharua, Burnihat and Mandira were added to generate location and crop specific agricultural production packages.
Makhana, an underutilize aquatic crop of Nympheaceae family, has various medicinal properties but has not gain much attention in the field of processed products and marketing. Value added product from makhana can be envisaged; however development of suitable processing technique for the same is still lacking. The objective of the study is to develop nutritious ready –to-reconstitute mix formulation using makhana as the prime ingredient. Makhana seed was ground into flour which was found to contain high amount of carbohydrate (69.06%) and protein (~9.69%). Makhana flour was subjected to two processing techniques i.e. roasting (100o C for 1, 3 and 5min) and steaming (100o C for 10, 15, 30, 45 and 60 min) for improving resistant starch (RS) content. RS was found to be highest in S8 (steaming for 60 min), followed by S2 (roasting for 3min) and S3 (roasting for 5min). Though steaming improved the RS content in makhana flour upto 0.92%, however the off-odour of steamed samples made them organoleptically unacceptable. While roasting eliminated the off-odour of makhana and also improved the RS value (0.58% to 0.84%); wherein S2 (0.84%) had the highest overall acceptability. As such S2 was selected for formulating ready-to-reconstitute mix by adding it with fig and banana flour at different proportion .These formulations were reconstituted in water /milk for assessing rehydration ratio, viscosity and sensory analysis. Rehydration ratio and viscosity were found maximum in T9 (60% makhana, 30% fig,10% banana) followed by T8 (60% makhana, 10% fig, 30% banana).High viscosity and rehydration ratio in these formulations were attributed to the presence of high amount of fig and banana flours having high crude fiber (2.08 % in banana and 4.14 % in fig).All the formulations received high mean score for colour, appearance and texture, taste, flavor and overall acceptability except T1 (contain makhana flour as control). The comments from the panelist revealed that natural sweetness of fig and banana sufficed the need of any extraneous sweetener in the formulations excluding the control (T1), where makhana gave a bland taste. T8 (60% makhana, 10% fig, 30% banana) scored the highest overall acceptability and was thus found to be suitable for making ready-to-reconstitute mix. Hence, suitably makhana flour (roasting) can be blended with other fruits and vegetables for making convenient foods.
The consumer demand is increasing for bakery products having high nutritional value and potential health benefit. The primary objective of the study is to produce baked goods using partial substitution of fat with papaya pulp concentrate and wheat flour with buckwheat and defatted soya flour. Cookies and muffins were prepared with different composite flour treatments of refined wheat flour, buckwheat flour and defatted soy flour in the ratio of 80:10:10 (T1). 70:20:10 (T2) and 60:30:10 (T3). Papaya pulp concentrate was obtained after drying papaya pulp at 60°±2°C for a period of 60, 90 and 120 minutes. The pulp concentrate with 120 minutes of drying was selected which contained total soluble solid content (20.5 ⁰Brix) double than that of the fresh pulp. This papaya pulp concentrate was used at 20%, 30%, 40% and 50% levels for replacing fat during baking. The organoleptic evaluation using 9 point hedonic scale revealed that cookies from the three composite flour treatments with 30% level of fat replacement scored highest in all the sensory attributes while for muffins, the composite flour treatments with 40% level of fat replacement received the highest scores. The physico-chemical analysis indicated that cookies and muffins of composite flour treatment T1 had the lowest fat content whereas composite flour treatment T3 for both the products were higher in nutritional composition. The protein, fiber and ash content of cookies increased to 17.82 g/100g, 2.27 g/100g and 1.56 g/100g with DPPH inhibition % 60.13% respectively and fat content decreased to 19.37 g/100g in comparision to control with 23.82 g/100g. For muffins, the protein, fiber and ash content increased to 19.02 g/100g, 2.35 g/100g and 1.79 g/100g with DPPH inhibition % 61.07% respectively and fat content decreased to 13.84 g/100g in comparision to control with 18.77 g/100g. The shelf-life of papaya pulp concentrate with different treatments was upto 5 days after which visible growth appeared. The pulp concentrate with preservative stored in refrigerator had the least microbial count on fifth day. The shelf-life of cookies packaged in air tight container and HDPE packages were upto 90 days in regard to both microbial load and sensory evaluation. The muffins were acceptable up to 14 days after which visible growth was visible. The overall acceptability of the bakery products decreased with increase in storage period. Thus it can be concluded that use of composite flour and papaya pulp concentrate in baked foods causes increased overall nutritional quality, decreased fat content and thereby trans fat and calorie content.
Investigations were carried out at the Departments of Horticulture and
the Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat,
during 2016-2018 on yoghurt developement from non-dairy plant sources like taro
and tapioca. The yoghurts were prepared by infusing taro and tapioca in soymilk
using bacterial cultures collected from the Depatment of Agricultural Biotechnology
and isolates from commercial yoghurts. Isolated strains were identified as
Streptococcus thermophilus PD5 MH569615, L. delbrueckii subsp. lactis PD7
MH569616 and L. brevis PD8 MH569617 for milk fermentation with the help of 16S
rDNA gene sequencing. Those strains were phylogenetically similar with their related
species. Through sensory evaluation of yoghurt samples, four yoghurts were selected
as best and those samples were AB9 (1:9 taro-soy yoghurt; 1:1 S. thermophilus and L.
delbrueckii subsp. lactis), CD19 (1:9 tapioca-soy yoghurt; 1:1 S. thermophilus and L.
delbrueckii subsp. lactis), CDY (1:9 tapioca-soy yoghurt; 1:1 S. thermophilus and L.
brevis), and CDZ (1.5:8.5 tapioca-soy yoghurt; 1:1 S. thermophilus and L. brevis).
The selected yoghurt samples were subject to physio-biochemical and microbiological
analysis which revealed that yoghurt AB9 contained the highest protein (6.47 g 100
g-1), fibre (0.25 g 100 g-1), viscosity (684.03 cP); but with the lowest moisture
(81.73%), carbohydrate (3.66 g 100 g-1), fat (0.28 g 100 g-1), acidity (0.34%) and pH
(4.20). On the basis of sensory evaluation and physio-biochemical properties, AB9
(1:9 taro-soy yoghurt; 1:1 S. thermophilus and L. delbrueckii subsp. lactis) was
considered as the best. The microbiological examination revealed that yoghurt had a
shelf life of 6 days with Lactobacilli count of 6.63 log cfu mL-1, S. thermophilus count
of 6.84 log cfu mL-1 with absence of coliform bacteria.
Chepa guti, a byproduct of the Xaj-brewing process is the lees left behind after
the liquid is separated from the fermented product. The technological advance in the
field of rice brewing is expected to witness an upsurge in brewing plant and an increase
generation of this byproduct. Chepa guti is specifically seen to retain starch and
fermentable sugars which can be used to produce down stream products like acetic acid.
Chepa guti collected from different localities were used as a source for isolation of
acetic acid bacteria. Three isolates that matched acetobacter species on biochemical
level were further characterized at the molecular level through 16SrDNA gene
sequencing and identified as Acetobacter indonesiensis, Acetobacter spp. and
Acetobacter tropicalis. The collected chepa guti was initially characterized at the
biochemical level and subjected to hydrolysis with commercial alpha-amylase at
different concentration for generating maximum amount of reducing sugar. The aamylase
at 0.3 per cent concentration in 1:1.5 substrate dilution (substrate : water) along
with fungal culture Amylomyces rouxii ABT82 (NCBI KP790015) at 48 hours of
incubation time produced maximum reducing sugars (73.41 mg 100mL-1). Simultaneous
saccharification and fermentation using the yeast isolate Saccharomyces cerevisiae ADJ
5 (NCBI KX904349) produced 8.19 % ethanol. This substrate was used to produce
acetic acid by inoculating pure culture of isolated acetic acid bacteria viz., Acetobacter
indonesiensis , Acetobacter spp , Acetobacter tropicalis along with a control inoculated
with reference strain Acetobacter aceti ATCC 15973 and treatment combination. Acetic
produced by the pure culture of Acetobacter tropicalis was significantly higher in terms
of acetic acid content of (9.08 %). It had pH (2.68), residual alcohol of (0.52 %), TSS of
(0.91 ˚Brix), residual reducing sugar of (0.25 mg 100 mL-1) and protein content of
(68.09 μg 100 mL-1). The LC-MS analysis of the produced acetic acid showed the
presence of compounds like O-Phosphoserine, 2',3'-Dideoxyadenosine, Phenylalanine,
2-(4-Hydroxyphenyl) propionic acid, Creatine, N-Tigloylglycine, S-Sulforaphene,
Triethyl phosphate, Metazachlor-OXA, Histidinol, Indole, Indoline, L-verbenone,
Indole-3-carbinol, DL-Pipercolic acid, 1-Aminocyclopropane carboxylic acid. The
Acetobacter tropicalis isolate was used in the scale up process where acetic acid content
of (11.26 %) was achieved by increasing the inoculum size. The study reveals the
potential of native acetic acid bacteria and development of a technology to produce
organic acetic acid from bio-waste. The study was successful in isolating and
identifying native acetic acid bacteria in Chepa guti and also was able to standardize the
production of vinegar from the biowaste.
An experiment entitled “Utilization of fruits and vegetables waste in cereal based food” was conducted in the Department of Horticulture during 2016 -2018. Powder from the mango kernel, pineapple pomace, carrot pomace, banana peel and orange peel was prepared. The wheat flour in the cookies and cakes formulation was substituted by MKP (mango kernel powder), PPP (pineapple pomace powder), CPP (carrot pomace powder), BPP (banana peel powder) and OPP (orange peel powder) at the rate of 0, 10, 20 and 30 per cent. Cookies and cakes were prepared and were analyzed for its physical (diameter, thickness and spread ratio), functional (water holding capacity, oil holding capacity and swelling capacity), chemical (moisture, ash, protein, fat, fibre, carbohydrate) and sensorial characteristics (appearance, colour, Flavour, taste, texture, overall acceptability). On the basis of overall sensory attributes, cookies prepared with incorporation of 10 per cent of MKP, PPP, CPP, BPP and OPP recorded higher acceptability scores as compared to other samples. In case of cakes the basis of overall sensory attributes, cakes prepared with 10 per cent of, PPP, CPP, BPP, OPP and 20 per cent MKP recorded higher acceptability values as compared to other samples. The water absorption capacity differed significantly. The highest value of (2.66 ml/g) was recorded in CPX (wheat flour substituted with 10% carrot pomace powder), the lowest value of 1.10 ml/g was recorded in wheat flour cookies. The spread ratio of cookies increased with incorporation fruits and vegetable waste powder. However, the differences in spread ratio of cookies were non-significant. The peroxide values and moisture content of cookies and cakes increased with increasing storage time. Cookies containing 10 per cent mango kernel powder and cakes containing 20 per cent mango kernel powder scored higher values in sensory evaluation.