Effect of maleylation on physicochemical and functional properties of rapeseed protein isolateDas Purkayastha, Manashi; Borah, Anuj; Saha, Sougata; Manhar, Ajay; Mandal, Manabendra; Mahanta, Charu
doi: 10.1007/s13197-016-2197-9pmid: 27413206
Influence of maleylation on the physicochemical and functional properties of rapeseed protein isolate was studied. Acylation increased whiteness value and dissociation of proteins, but reduced free sulfhydryl and disulfide content (p < 0.05). Intrinsic fluorescence emission and FTIR spectra revealed distinct perturbations in maleylated proteins’ tertiary and secondary conformations. Increase in surface hydrophobicity, foaming capacity, emulsion stability, protein surface load at oil-water interface and decrease in surface tension at air-water interface, occurred till moderate level of modification. While maleylation impaired foam stability, protein solubility and emulsion capacity were markedly ameliorated (p < 0.05), which are concomitant with decreased droplet size distribution (d
32). In-vitro digestibility and cytotoxicity tests suggested no severe ill-effects of modified proteins, especially up to low degrees of maleylation. The study shows good potential for maleylated rapeseed proteins as functional food ingredient.
Microbiological stability and quality of pulsed light treated cantaloupe (Cucumis melo L. reticulatus cv. Glamour) based on cut type and light fluenceKoh, Pei; Noranizan, Mohd; Karim, Roselina; Nur Hanani, Zainal
doi: 10.1007/s13197-015-2139-ypmid: 27413207
The aim of this study was to investigate the effect of cut type and pulsed light (PL) fluence on microbiological stability and quality of fresh-cut cantaloupes. Fresh-cut cantaloupes with various cut types (cuboid, triangular prism and sphere) were treated with PL technology at 6 J/cm2. Samples were exposed to PL treatment at fluences of 2.7, 7.8, 11.7 and 15.6 J/cm2 followed by storage at 4 ± 1 °C for 28 days. Microbiological quality, headspace composition, firmness, colour, pH, titratable acidity, total soluble solids, total phenolic content and ascorbic acid content of fresh-cut cantaloupes were determined. Spherical shape was found to be the most suitable shape for PL treatment of fresh-cut cantaloupes due to its significantly lowest (p ≤ 0.05) microbial counts before and after the PL treatment. No significant (p > 0.05) effect was observed for firmness, colour, total soluble solids and total phenolic content of fresh-cut cantaloupes throughout the storage study. Pulsed light treatment using 7.8 J/cm2 was the best for extending shelf life of fresh-cut cantaloupes with extension of 8 days longer at 4 ± 1 °C compared to the control while maintaining the ascorbic acid content. In conclusion, PL treatment is a potential technique for extending the shelf life of fresh-cut cantaloupes by inactivating microorganisms without compromising the nutritional value.
Antioxidant activity of various extracts of selected gourd vegetablesYadav, Baljeet; Yadav, Roshanlal; Yadav, Ritika; Garg, Munish
doi: 10.1007/s13197-015-1886-0pmid: 27413209
Study was conducted to evaluate the antioxidative activity of methanolic (ME), ethanolic (EE) and butanolic extracts (BE) of selected gourd vegetables. The antioxidant activity was investigated using different assays namely ferric thiocyanate test (FTC), thiobarbituric acid test (TBA), ferric reducing antioxidant power (FRAP) and DPPH free radicals scavenging test. A densitometric HPTLC analysis was performed for the analysis of phenolic acids and flavonoids. Different extracts of the selected gourd vegetables revealed different antioxidant activity. Different extracts of Lagenaria siceraria, Momordica charantia and Luffa cylindrica revealed significantly higher (p < 0.05) concentrations of total phenols, flavonids, tannins and carotenoids content and also the antioxidant activity in comparison to remaining vegetable extracts. Correlation studies indicated that FRAP test best described the antioxidant activity of phenols, flavonoids and carotenoids (r = 0.854, 0.692 and 0.915 respectively). HPTLC profiles revealed the presence of maximum number of phenolic acids and flavonoids in L. siceraria and M. charantia.
Optimization of food materials for development of nutritious pasta utilizing groundnut meal and beetrootMridula, D.; Gupta, R.; Bhadwal, Sheetal; Khaira, Harjot; Tyagi, S.
doi: 10.1007/s13197-015-2067-xpmid: 27413210
Present study was undertaken to optimize the level of food materials viz. groundnut meal, beetroot juice and refined wheat flour for development of nutritious pasta using response surface methodology. Box-benken design of experiments was used to design different experimental combinations considering 10 to 20 g groundnut meal, 6 to 18 mL beetroot juice and 80 to 90 g refined wheat flour. Quality attributes such as protein content, antioxidant activity, colour, cooking quality (solid loss, rehydration ratio and cooking time) and sensory acceptability of pasta samples were the dependent variables for the study. The results revealed that pasta samples with higher levels of groundnut meal and beetroot juice were high in antioxidant activity and overall sensory acceptability. The samples with higher content of groundnut meal indicated higher protein contents in them. On the other hand, the samples with higher beetroot juice content were high in rehydration ratio and lesser cooking time along with low solid loss in cooking water. The different level of studied food materials significantly affected the colour quality of pasta samples. Optimized combination for development of nutritious pasta consisted of 20 g groundnut meal, 18 mL beetroot juice and 83.49 g refined wheat flour with overall desirability as 0.905. This pasta sample required 5.5 min to cook and showed 1.37 % solid loss and rehydration ratio as 6.28. Pasta sample prepared following optimized formulation provided 19.56 % protein content, 23.95 % antioxidant activity and 125.89 mg/100 g total phenols with overall sensory acceptability scores 8.71.
Geometrical, functional, thermal, and structural properties of oat varieties from temperate region of IndiaShah, Asima; Masoodi, Farooq; Gani, Adil; Ashwar, Bilal
doi: 10.1007/s13197-015-2119-2pmid: 27413212
Geometrical, functional, thermal properties and FTIR analysis of three varieties of oat flour (Sabzaar, SKO20, & SKO90) were investigated. Sabzaar showed highest thickness, geometric mean diameter, arthimetic mean diameter, sphericity and grain volume. The density of oat grains varied from 0.393 to 0.37 g/mL (bulk) and 1.2 to 1.8 g/mL (true). WAC showed significant (P < 0.05) difference among the cultivars with Sabzaar flour showing the highest value (2.36 g/g) and SKO20 (1.98 g/g) the lowest. Peak viscosity of oat flours was in the range of 460.33–489.33 cP. Flour samples showed the presence of small as well as large starch granules, oval or irregular shape with a smooth surface having some dents or fissures and some damaged starch and with varying dimensions. Average granule size of oat starch samples was within the range of 1.5–6.6 μm in Sabzaar, 1.1–5.2 μm in SKO20, and 1.7–6.8 μm in SKO90. The gelatinization transition temperatures onset temperature (To), peak temperature (Tp), and conclusion temperature (Tc) varied significantly (p < 0.05) among three varieties.
Antioxidant and cyto/DNA protective properties of apple pomace enriched bakery productsSudha, M.; Dharmesh, Shylaja; Pynam, Hasitha; Bhimangouder, Shivaleela; Eipson, Sushma; Somasundaram, Rajarathnam; Nanjarajurs, Shashirekha
doi: 10.1007/s13197-015-2151-2pmid: 27413217
Apple pomace (AP), the residue that remains after the extraction of juice from apple accounts for ~25 % of total apple weight. Current study is aimed at identification of phytochemicals and utilization of Dehydrated apple pomace (DAP) in the preparation of bakery products with potential health benefits. DAP was prepared by drying the pomace obtained by crushing peeled apple fruits. DAP was incorporated into bakery products such as bun, muffin and cookies for value addition. Bioactivity such as free radical scavenging, cyto/DNA protectivity was evaluated in these products. DAP contained 17 g/100 g starch, 49.86 g/100 g fructose and 37 g/100 g dietary fibre. The phenolics and flavonoids content was 1.5 mg/g and 3.92 mg/g, respectively. Increase in DAP resulted in decreased volume and enhanced firmness of buns and muffins. DAP at 15 % in buns, 30 % in muffins and 20 % in cookies were found to be acceptable. DAP blended products exhibited better free radical scavenging as well as cyto/DNA protective properties suggesting the retention of bioactivity after baking. Addition of DAP potentially enhanced the bioactivity of the products evaluated.
Malting process optimization for protein digestibility enhancement in finger millet grainHejazi, Sara; Orsat, Valérie
doi: 10.1007/s13197-016-2188-xpmid: 27413219
Finger millet (Eleusine coracana) is a nutritious, gluten-free, and drought resistant cereal containing high amounts of protein, carbohydrate, and minerals. However, bio-availability of these nutrients is restricted due to the presence of an excessive level of anti-nutrient components, mainly phytic acid, tannin, and oxalate. It has been shown that a well-designed malting/germination process can significantly reduce these anti-nutrients and consequently enhance the nutrient availability. In the present study, the effects of two important germination factors, duration and temperature, on the enhancement of in-vitro protein digestibility of finger millet were thoroughly investigated and optimized. Based on a central composite design, the grains were germinated for 24, 36, and 48 h at 22, 26, and 30 °C. For all factor combinations, protein, peptide, phytic acid, tannin, and oxalate contents were evaluated and digestibility was assessed. It was shown that during the malting/germinating process, both temperature and duration factors significantly influenced the investigated quantities. Germination of finger millet for 48 h at 30 °C increased protein digestibility from 74 % (for native grain) up to 91 %. Besides, it notably decreased phytic acid, tannin, and oxalate contents by 45 %, 46 %, and 29 %, respectively. Linear correlations between protein digestibility and these anti-nutrients were observed.
Postharvest shelf-life extension of pink guavas (Psidium guajava L.) using HPMC-based edible surface coatingsVishwasrao, Chandrahas; Ananthanarayan, Laxmi
doi: 10.1007/s13197-015-2164-xpmid: 27413223
Psidium guajava L. var. ‘Lalit’ is a perishable fruit with delicate skin which is prone to damage. The objective of this study was to determine the effect of edible coating made up of hydroxypropyl methyl cellulose and palm oil on ripening of guava. Coating solution was applied over fruits and coated fruits were stored at 24 ± 1 °C and 65 ± 5%RH. Changes in fruit colour, texture softening, respiration rate, weight loss, ascorbic acid content, soluble solids, titrable acidity, chlorophyll content, total reducing sugars, total phenolic content were studied during post-harvest ripening. Fruits coated with 1 % of hydroxypropyl methyl cellulose and 0.3 % of palm oil showed significant delay in weight loss, fruit firmness as well as colour change (p < 0.05). Coating delayed the enzyme activities of peroxidase and polyphenol oxidase of the fruit. Results suggest that overall quality of coated fruit was maintained by edible coating formulation extending the shelf life of fruit up to 12 days with appreciable retention of all quality parameters tested.
Application of edible coating with starch and carvacrol in minimally processed pumpkinSantos, Adriele; Silva, Alex; Amaral, Viviane; Ribeiro, Alessandra; Abreu Filho, Benicio; Mikcha, Jane
doi: 10.1007/s13197-016-2171-6pmid: 27413224
The present study evaluated the effect of an edible coating of cassava starch and carvacrol in minimally processed pumpkin (MPP). The minimal inhibitory concentration (MIC) of carvacrol against Escherichia coli, Salmonella enterica serotype Typhimurium, Aeromonas hydrophila, and Staphylococcus aureus was determined. The edible coating that contained carvacrol at the MIC and 2 × MIC was applied to MPP, and effects were evaluated with regard to the survival of experimentally inoculated bacteria and autochthonous microflora in MPP. Total titratable acidity, pH, weight loss, and soluble solids over 7 days of storage under refrigeration was also analyzed. MIC of carvacrol was 312 μg/ml. Carvacrol at the MIC reduced the counts of E. coli and S. Typhimurium by approximately 5 log CFU/g. A. hydrophila was reduced by approximately 8 log CFU/g, and S. aureus was reduced by approximately 2 log CFU/g on the seventh day of storage. Carvacrol at the 2 × MIC completely inhibited all isolates on the first day of Storage. coliforms at 35 °C and 45 °C were not detected (< 3 MPN/g) with either treatment on all days of shelf life. The treatment groups exhibited a reduction of approximately 2 log CFU/g in psychrotrophic counts compared with controls on the last day of storage. Yeast and mold were not detected with either treatment over the same period. The addition of carvacrol did not affect total titratable acidity, pH, or soluble solids and improved weight loss. The edible coating of cassava starch with carvacrol may be an interesting approach to improve the safety and microbiological quality of MPP.
Preparation, characterization and in vitro antioxidative potential of synbiotic fermented dairy productsShah, C.; Mokashe, N.; Mishra, V.
doi: 10.1007/s13197-016-2190-3pmid: 27413225
The present study, evaluates the antioxidative potential of two synbiotic dairy products viz. synbiotic lassi with honey and whey based synbiotic drink with inulin and orange juice, along with their physicochemical and microbiological activity during storage period. Antioxidative potential of raw ingredients and probiotic cultures used to prepare synbiotic products was also evaluated. Synbiotic lassi with honey was prepared using Streptococcus thermophilus MTCC 5460 (MD2) and Lactobacillus helveticus MTCC 5463 (V3) as probiotics and honey as prebiotic. For preparation of whey based synbiotic drink, Lactobacillus helveticus MTCC 5463 and inulin were used as probiotic and prebiotic, respectively and orange juice was also incorporated. Titratable acidity and pH of both synbiotic products followed a similar pattern of increase or decrease during storage. Furthermore, no major changes were observed in viability of probiotic cultures under storage conditions adapted. The hydroxyl radical scavenging activity of synbiotic lassi with honey was found to significantly decrease from 107.76 to 79.41 % at the end of storage whereas, the activity of whey based synbiotic drink was 100.32 % which declined sharply to 79.21 % on 7th day but further increased to 102.59 % on 14th day. The DPPH (α, α-Diphenyl-β-Picrylhydrazyl) radical scavenging activity of freshly prepared synbiotic lassi with honey was 28.43 % which decreased to 23.03 % on 7th day while for whey based synbiotic drink decreased from 26.85 % (0 day) to 17.12 % (7th day) and continued to decline. Moreover, probiotic strains used for synbiotic preparation also demonstrated good antioxidative activity.