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Harvest maturity was specified for 'Langra', 'Dusehri' and 'S.B. Chaunsa' mango varieties with 1-methylcyclopropene (1-MCP) application for preserving maximum postharvest quality of mango during low temperature storage (30 days). 1-MCP was applied at 0, 250, 500, 1000 and 2000 nL·L-1 concentration. Ripening indices were observed of each variety at every 10th day for mature green (M1) and sprung (M2) maturity stages. Total soluble solids (TSS) and titratable acidity (TA) decreased with the passage of time, while 1-MCP treated fruit retained higher TSS and TA during storage. Rate of respiration (mmoles CO2·kg-1·h-1) increased gradually till climacteric rise occurred but less peak height was observed at M1 under 1-MCP application. Physiological weight loss (%) of 1-MCP treated fruit reduced, resultantly less wilting and skin shriveling was observed at M1. Peel color changes in control treatment was rapid (yellow color with black spots) with increased ripening index at M2 stage. Peel color of 'Langra' mango remained green among treatments, while fruit of 'Dusehri' and 'S.B. Chaunsa'when subjected to 1-MCP showed least color score (51 to 75 % yellowing) at M1 and M2, respectively. 1-MCP delayed ripening of mango fruit at low to moderately high concentration depending upon the fruit variety for 15 (M2) to 20 days (M1). 'Langra' mango showed best response to 500 while 'Dusehri' and 'S.B. Chaunsa' varieties at 1000 nL·L-1 concentration of 1-MCP. It can be concluded that 1-MCP in combination with other postharvest strategies found effective in maintaining good keeping quality of mango when fruit harvested at mature green stage (M1). [ABSTRACT FROM AUTHOR]

Milk is a highly nutritious and valuable food throughout the world. A major portion of its production is wasted due to low processing rate and if processed then the high temperature affects its nutritional quality. This study was specifically designed to process buffalo milk by ultraviolet (UV) radiation and checking its effect on the fatty acid profile of the milk as compared to heat treatment. Two variables were used each at three levels that were UV intensity (1780uW/cm², 2300uW/cm² and 3000uW/cm²) and time duration (5min, 10min, 15min). The results of these UV treatments were compared with the thermal treatment (82oC for 15 seconds). It was observed that the heat treatment had a significant effect on the Total Solids changed from 15.88-18.57%), total fat (changed from 6.35-6.78%) and Solids not fat (changed from 9.61-10.63%) content of the milk. Whereas, the heat treatment had non-significant effect on the pH (changed from 7.11-7.32) and titratable acidity (changed from 0.09-0.08) of the milk. Fatty acid profile was also significantly affected by heat treatment as a lot of isomerization took place that also caused the increase in the trans fatty acids (content of Linoleic acid trans increased from 0.14 to 0.45). Oxidation was also responsible for the changed fatty acid profile of the buffalo milk. Whereas, UV light treatment did not affect the fatty acid profile of the milk significantly. Sensory characteristics of the milk were significantly changed by the action of the heat treatment as compared to the UV treatments that did not have any impact on the sensory characteristics of the milk. Conclusively, the UV treatment had far better results on the physicochemical properties and fatty acid profile of the milk as compared to the heat treatment. [ABSTRACT FROM AUTHOR]

Pesticides are applied on grapevines to combat various pests which are catastrophic for grapes and cause menace for farmers. Hence, to investigate the fate of difenconazole and cymoxanil their supervised trial was conducted on 2 grape varieties with 3 doses of each. Perlette variety is elliptical and sweet in taste with greenish color whereas black grapes are round and have blackish appearance with sweet and sour taste. Moreover, black grape has thick skin as compared to perlette. The residues (mg Kg-1) of cymoxanil dissipated from 2.44±0.11 to 0.18±0.02 at recommended dose (RD), 3.08±0.25 to 0.21±0.02 at double dose (DD) and 5.70±0.29 to 0.26±0.02 at triple dose (TD) on perlette while 2.42±0.14 to 0.078±0.007 at RD, 3.45±0.28 to 0.003±0.001 at DD and 5.71±0.28 to 0.083±0.008 at TD on black grape, correspondingly showing greater dissipation. Similar trend was witnessed from perlette where difenconazole residues (mg Kg-1) dissipated from 9.41±0.24 to 0.45±0.03 at RD, 15.98±1.42 to 0.66±0.023 at DD while 23.93±0.31 to 0.74±0.040 at TD. Nonetheless, on black grapes difenconazole disappeared more as compared to perlette from initial to final residues (mg Kg-1) i.e.9.64±0.21 to 0.26±0.015 at RD, 16.13±0.42 to 0.53±0.048 at DD but 24.15±1.57 to 0.026±0.002 at TD, respectively. Mathematical first order model having exponential decay was best fitted to forestated residues where allied parameters (half-life, end point identifier i.e. DT90) were calculated for both varieties and pesticides. Cymoxanil dissipated earlier than difenconazole and black grapes represented excellent pesticide loss than perlette. [ABSTRACT FROM AUTHOR]

The objective of the current research was to assess the optimal extraction conditions with respect to ethanol concentration and time to recover betalains from red beetroot (Beta vulgaris L.). Purposely, betalains were extracted from beetroot using water and ethanol based solvent modules at three different time intervals i.e., 20, 40 and 60 min and the obtained extracts were analyzed for betacyanins, betaxanthins and total betalains. The obtained data was further analyzed using three level-two factor central composite design using response surface methodology. The data was fitted to second order polynomial equation by applying multiple regression analysis. The optimal conditions were obtained using maximum desirability function that found to be 31.03, 45.01 and 35.34% aqueous ethanol for betacyanins, betaxanthins and total betalains, respectively whilst, optimum extraction time was recorded to be around 43 min. The experimental values were close to the predicted values that proves the adequacy of the model employed. It was suggested that aqueous-ethanol is suitable for maximal recovery of beetroot betalains instead of ethanol or water as a sole solvent. [ABSTRACT FROM AUTHOR]

1-Methylcyclopropene (1-MCP) was used as an ethylene antagonistic in the present research to suppress the ethylene induced ripening and preserve the post-harvest quality of guava. Physiologically mature guava (cvs. 'Gola' and 'Surahi') were exposed to 1-MCP with different levels (0, 200, 500 and 800 nL·L-1). Samples were held at 10°C and 80% RH and ripening indices were measured every 6 days for 1 month. The patterns for soluble solids and ethylene were typical of climacteric fruit for both cultivars. Results illustrated that ripening advanced rapidly for the fruits without 1-MCP. 1-MCP significantly reduced the weight loss, which was higher in 'Gola' compared to 'Surahi'. Control fruits started to decay at day 12, whereas, treated decayed on day 18. Low to intermediate levels of 1-MCP was effective in preserving desirable firmness. Control fruits showed change in Hue angle from yellowish green to ripe yellow at 6th day compared to 1-MCP treated which delayed the color change to 12-18 days. The data suggest that dose levels of 1-MCP below 800 nL·L-1 were not sufficient to saturate the response to 1-MCP. [ABSTRACT FROM AUTHOR]

The aim of this research was to isolate lactic acid bacterial (LAB) strains, characterize them and classify the bacteriocin producing LAB strain from indigenous dairy sources. Antimicrobial potential of LAB strain was tested against L. monocytogens. The antimicrobial compound was also tested for maintaining the decreased colony forming unit (CFU) for minimally processed vegetables like carrots, cabbage and lettuce in second phase of the research. The initial identification was based on conventional morphological and biochemical analysis while the final confirmation was done by utilizing advanced molecular tools. Prior to all these manipulations the growth conditions were carefully optimized for the respective strains. The study finally led us to conclude that Lactococcus lactis subsp. lactis was the most abundant type of lactic acid bacteria found in indigenous dairy products (sour cream and cheese) samples studied. A bacteriocin (Lacticin SC07) produced during the growth of Lactococcus lactis subsp. lactis was purified partially by using biochemical technique ammonium sulfate precipitation in different percentages (60% and 80%). These precipitations lead to a 437-fold increase in total lacticin SC07 activity. SDS-PAGE electrophoretic pattern of lacticin showed that it is a single peptide band of 1.7 kDa. But, 3.7 kDa dimers also showing lacticin SC07 activity. The findings of my research revealed that the isolated LAB strain has good potential for bacteriocin production and antimicrobial potential that exerts in the usage of this bacteriocin (lacticinSC07) as a natural preservative in minimally processed vegetable industry. [ABSTRACT FROM AUTHOR]

Low sugars and light frying color are key traits to be observed during storage while assorting the potatoes for chips/fries preparation. Selecting the best cultivars reflects an important element for effective and economical processing by the industry. Six commercial potato cultivars were selected to evaluate their behavior and chipping potential regarding sugar accumulation during storage for a period of 160 days at various temperatures (3, 7 and 11°C). All the temperatures posed significant effect on sugar contents during storage however, high sugar accumulation was noticed at 3°C for all the cultivars ranged from 29.03 to 255.38 for glucose, 26.78 to 253.11 for fructose and 55.33 to 114.45 mg100-1 g fresh weight for sucrose. Storage at 11°C had least effect on sugar accumulation than 3°C and 7°C. Chips color was used as an index to evaluate the processing quality as well as sugar accumulation. At the end of storage, sugar accumulation and chips color were found in order of (low to high) Lady Rosetta < Hermes < Crozo < Asterix < Santé < Kuroda. Consequently, significant variability among the cultivars was observed whereas Lady Rosetta (golden yellow), Hermes (slightly yellow) and Crozo (yellow) were found to be the most suitable cultivars for fries/chips preparation. [ABSTRACT FROM AUTHOR]

Volatile compounds in fermented sourdoughs were formed by using starter cultures [Lactobacillus brevis (St-I), Lactobacillus fermentum (St-II) and Lactobacillus plantarum (St-III)] along with control starter culture (Saccharomyces cerevisiae). Sourdough samples were obtained by fermenting the dough with starter cultures at different fermentation times (12, 18 and 24 hrs). Furthermore, the fermented samples were analyzed for pH, total titratable acidity (TTA), organic acids, sugars and volatile compounds. From the results, it is noticed that the pH decreased as a function of fermentation time in all starter cultures and maximum pH drop was observed in St-II after 24 h of fermentation followed by St-I at the same time interval. However, least drop in pH was recorded in the control starter culture. Moreover, highest TTA (10.30%) was produced by St-I after 24 h of fermentation followed by the same culture at 18 h of fermentation (9.90%). Conversely, the control samples yielded lowest TTA. In case of organic acids and sugars after evaluating by HPLC depicted that St-I gave more concentrations of sugar fractions (maltose and fructose) and St-II produce higher concentrations of organic acids, all sugar contents and organic acids increased with passage of time. Sourdough samples were analyzed for volatile compounds by GC-MS through headspace analysis. Sourdough produced by the addition of starter cultures yielded 1-hexanol, hexanal, octanal and ethyl acetate in general whereas, diacetyl was produced in St-III ferments only. [ABSTRACT FROM AUTHOR]

Roller flour milling separates wheat components through series of break and reduction rolls along with different sifting operations. Protein (13.70%) and moisture (13.60%) contents were highest in Inqulab 91 break stream blend. Break flour blend of wheat variety Inqulab 91 had Zeleny value of 41mL and gluten content 33% that was found an equivalent to mean for gluten content and Zeleny value in AS 02 break stream blend. Cookie thickness (7.06mm) was highest in cookies made from AS 02 straight grade flour, diameter (25.77mm) and spread factor (41.48) in AS 02 sizing blend while cookie weight (8.24g) in AS 02 break blend. Among sensory characteristics, mean for cookie colour (7.80) was highest in AS 02 break blend while score for crispness (7.80), taste (7.20), surface characteristics (7.60) and overall acceptability (8.00) was maximum in AS 02 middling blend. It is concluded from results that physical parameters of cookie like diameter, spread factor and weight improved with blending while cookie thickness decreased. Cookies made from blended flours exhibited better color, crispness, taste, surface characteristics and overall acceptability. Cookies made from AS 02 middling stream blend were preferred by judges on overall sensory profile basis. [ABSTRACT FROM AUTHOR]