Characterization of volatile components from ginger plant at maturity and its value addition to ice cream.

Ginger is widely consumed spice across the globe and especially in Asian countries routinely employed in various culinary preparations. Ginger possesses many distinct bioactive molecules, have shown marked therapeutic benefits. The ginger aroma is mainly due to the volatile compounds present in the rhizome. The current paper focuses on comparison of volatile constituents present in different plant parts of ginger concerning maturity and effect of incorporation of freeze-dried ginger extract into ice cream. Fresh ginger was collected for 5 months (every 30 days) and analysed for their differences in volatile composition with respect to maturity. Later ginger juice was extracted from fresh ginger and freeze-dried. Freeze-dried ginger powder was incorporated into icecream at various concentrations and studied the microbiological and sensory quality. Results from GC-MS profiles revealed the dominance of sesquiterpenes. Zingiberene a major volatile compound, increased from 2.52 to 18.15% with an increase in maturity days, whereas ar-curcumin decreased from 12.58 to 3.84%. The freeze-dried ginger powder yielded 10.2 ± 0.1% of oleoresin, which consists of 3.6 ± 0.2% of 6-gingerol. The value added ice cream with gingerols had the desirable sensory attributes with the novelty of natural ginger flavour. Icecream was pleasant, with attractive visual appeal, which is an essential determinant for consumer acceptance. The microbial quality of the ice cream was compared with the FSSAI standards, and the study was found to be within acceptable limits.

Effect of normal/dehydrated greens on the rheological, microstructural, nutritional and quality characteristics of paratha-an Indian flat bread.

The leaves of dill (Anethum graveolens) and fenugreek (Trigonella foenum-graecum L. Leguminosae) were dehydrated using low temperature low humidity dryer, packed in polypropylene bags and stored at refrigerated conditions. Dehydration process marginally reduced the chlorophyll, carotenoid and ascorbic acid contents. Replacement of whole wheat flour with dehydrated leaves (dill-DDL, fenugreek leaves DFL) at 0, 5, 7.5 and 10 % increased the water absorption (68.5 to 70.2 %), dough development time (3.5 to 5.9 min) and mixing tolerance index values (78 to 98 BU). Pasting temperature increased (69 to 74.1 °C), whereas the hot paste viscosity (255 to 210 BU) and cold paste viscosity values (355 to 295 BU) decreased with increase in the DDL/DFL content in the blend. Sensory evaluation of parathas prepared with either normal dill/fenugreek leaves (NDL/NFL) at 0, 12.5, 25 and 37.5 % or dehydrated leaves at 0, 5, and 7.5 % showed that parathas with 25 % of normal leaves and 7.5 % of dehydrated leaves were acceptable. Microstructure of the fenugreek leaves had more porous structure on dehydration. Parathas enriched with either of leaves were rich in dietary fiber, chlorophyll and carotenoid content.

Effect of pretreatments on extraction of pigment from marigold flower.

Marigold flower (Tagetes erecta L) is one of the richest sources of xanthophylls. An enzymatic pretreatment method was developed for improved extraction of pigments from marigold flowers. Pretreatment with enzyme solution increased the diffusion coefficient from 1.56 x 10(-9) m(2)/s to 4.02 x 10(-9) m(2)/s and mass transfer coefficient from 0.14 h(-1) to 0.36 h(-1) coefficients. At the same time, dry yield, resin yield and pigment yield were also found to increase along with increased retention of colour. Sodium hydroxide or citric acid pretreatments increased the diffusion coefficient during drying, but resulted in lower dry yield due to loss of soluble compounds whereas, pigment yield was higher as compared to control. The enzyme treated and air dried sample, stored at 4 °C was found to be the most stable, as indicated by a low (0.0006 day(-1)) degradation constant. Pretreatment of marigold flowers with an aqueous enzyme solution (0.2%) results in improved resin, pigment yield and retention of pigment during storage. Pretreatment of marigold flowers with sodium hydroxide citric acid followed by hydraulic pressing resulted in a significant reduction of water and also indicated improved dry yield, resin yield and pigment yield as compared to control sample.

Simple HPLC method for resolution of curcuminoids with antioxidant potential.

Development of methodology for qualitative analysis and quantitative separation of individual curcuminoids in curcumin removed turmeric oleoresin (CRTO) and study of antioxidant activity of individual curcuminoids have been achieved in the present study. A simple HPLC protocol was outlined for optimal resolution of curcuminoids (I), (II), and (III) on an Exil-NH(2) column using isocratic elution with a mixture of isopropanol and water. CRTO is shown to be good source for the compounds II and III, as they are in an enriched form. The optimum resolution of the curcumin and its analogs in the present method developed, affords a facile method for estimation of individual curcuminoids in turmeric samples, which is an improvement over the standard AOAC method which estimates only total curcuminoids. The free radical scavenging capacity of pure curcuminoids I, II, and III, as determined by DPPH method at 100 ppm concentration was 88%, 80%, and 68% with IC(50) values being 56, 62, and 73 ppm, respectively. Their antioxidant potential could render them useful as important nutraceuticals or functional food ingredients.

Studies on the antioxidant activities of natural vanilla extract and its constituent compounds through in vitro models.

Vanilla extract was prepared by extraction of cured vanilla beans with aqueous ethyl alcohol (60%). The extract was profiled by HPLC, wherein major compounds, viz., vanillic acid, 4-hydroxybenzyl alcohol, 4-hydroxy-3-methoxybenzyl alcohol, 4-hydroxybenzaldehyde and vanillin, could be identified and separated. Extract and pure standard compounds were screened for antioxidant activity using beta-carotene-linoleate and DPPH in vitro model systems. At a concentration of 200 ppm, the extract showed 26% and 43% of antioxidant activity by beta-carotene-linoleate and DPPH methods, respectively, in comparison to corresponding values of 93% and 92% for BHA. Interestingly, 4-hydroxy-3-methoxybenzyl alcohol and 4-hydroxybenzyl alcohol exhibited antioxidant activity of 65% and 45% by beta-carotene-linoleate method and 90% and 50% by DPPH methods, respectively. In contrast, pure vanillin exhibited much lower antioxidant activity. The present study points toward the potential use of vanilla extract components as antioxidants for food preservation and in health supplements as nutraceuticals.