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It is to be noted from various studies that the protein content of wheat grains and flour do not change significantly over time (Kim et al 2003). While protein quantity may not change, protein quality does. In one of the studies it was noted that total content of starch gets reduced after certain time when the grains are kept within controlled temperature. In India, wheat gets harvested in the months of March and early April. The atmospheric temperature varies from 25℃ – 45℃ in summer in different parts of India. The total starch content of the flour got decreased by 50 % when stored at 50℃ in comparison to the freshly harvested wheat grains<ref>Seguchi, M. 1993. Effect of wheat flour aging on starch-granule surface proteins. J.Cereal Chem. Vol.70: 362-364.  </ref>  <ref> Shearer, G., Patey, A. L., and McWeeney, D. J. 1975. Wheat flour proteins: The selectivity of solvents and the stability of gliadin and glutenin fractions of stored flours. J. Sci. Food Agric. 26:337-344. </ref>. This is a significant change that occurs due to aging of wheat. If the starch content of wheat is reduced with time, aged wheat will have lower calorific value and lower glycemic index. It will also be easier to digest. Similar changes have been observed in rice after aging. Post harvest storage has, it has been observed, significant effect on eight known textural properties that are important to the sensory characteristics of cooked rice: adhesion to lips, hardness, cohesiveness of mass, roughness of mass, toothpull, particle size, toothpack, and loose particles<ref> sourced from : https://www.uark.edu/ua/uarpp/Publications/Sensory/Meullenet%20et%20al%202000%20Cereal%20Chem.pdf downloaded on 24/12/2016 </ref>. A difference is observed between ageing of rice flour and rice starch. It is evident that pasting properties of fresh and aged rice are different. It is also reported that the cell wall structure is decomposed by endo –xylanase during storage which led to the changes in amylograms of rice fours<ref> Shibuya, N. and Iwasaki, T. Eff ect of cell wall degradingenzymes on the cooking properties of milled rice and the texture of cooked rice. J Jpn Soc Food Sci Technol 31(1984) 656–660.  </ref>.  
 
It is to be noted from various studies that the protein content of wheat grains and flour do not change significantly over time (Kim et al 2003). While protein quantity may not change, protein quality does. In one of the studies it was noted that total content of starch gets reduced after certain time when the grains are kept within controlled temperature. In India, wheat gets harvested in the months of March and early April. The atmospheric temperature varies from 25℃ – 45℃ in summer in different parts of India. The total starch content of the flour got decreased by 50 % when stored at 50℃ in comparison to the freshly harvested wheat grains<ref>Seguchi, M. 1993. Effect of wheat flour aging on starch-granule surface proteins. J.Cereal Chem. Vol.70: 362-364.  </ref>  <ref> Shearer, G., Patey, A. L., and McWeeney, D. J. 1975. Wheat flour proteins: The selectivity of solvents and the stability of gliadin and glutenin fractions of stored flours. J. Sci. Food Agric. 26:337-344. </ref>. This is a significant change that occurs due to aging of wheat. If the starch content of wheat is reduced with time, aged wheat will have lower calorific value and lower glycemic index. It will also be easier to digest. Similar changes have been observed in rice after aging. Post harvest storage has, it has been observed, significant effect on eight known textural properties that are important to the sensory characteristics of cooked rice: adhesion to lips, hardness, cohesiveness of mass, roughness of mass, toothpull, particle size, toothpack, and loose particles<ref> sourced from : https://www.uark.edu/ua/uarpp/Publications/Sensory/Meullenet%20et%20al%202000%20Cereal%20Chem.pdf downloaded on 24/12/2016 </ref>. A difference is observed between ageing of rice flour and rice starch. It is evident that pasting properties of fresh and aged rice are different. It is also reported that the cell wall structure is decomposed by endo –xylanase during storage which led to the changes in amylograms of rice fours<ref> Shibuya, N. and Iwasaki, T. Eff ect of cell wall degradingenzymes on the cooking properties of milled rice and the texture of cooked rice. J Jpn Soc Food Sci Technol 31(1984) 656–660.  </ref>.  
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These changes in physiochemical properties of grains exert their effect on digestibility of the food. It has been studied through experiments that the moisture content is higher in new grains indicating predominance of ''apa'' and ''prithvi mahabhuta'' which again tends towards ''santaparana''. Aging of rice has an impact on its glycemic index and glycemic load. New grain may have higher glycemic index than the older grain. Due to the effect of time on these food stuffs there are greater possibilities that certain amino acids and phyto chemicals get stabilized in the grain that make them safe for consumption.  
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These changes in physiochemical properties of grains exert their effect on digestibility of the food. It has been studied through experiments that the moisture content is higher in new grains indicating predominance of ''apa'' and ''prithvi mahabhuta'' which again tends towards ''santarpana''. Aging of rice has an impact on its glycemic index and glycemic load. New grain may have higher glycemic index than the older grain. Due to the effect of time on these food stuffs there are greater possibilities that certain amino acids and phyto chemicals get stabilized in the grain that make them safe for consumption.  
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''Navamadya''/fresh wine: New or fresh wines should not be consumed because they cause heaviness and create imbalances in all the three ''doshas'' while old wines promote circulation in the body, increase digestion, lightness and enhance taste in food. The effect of aging on tannins and resveratrol has been studied and shows significant difference between old and fresh wine. Aging results in altered and reduced phenolic contents in red wine. Anthocyanin tannin complexes can be formed which can stabilize the colour of red wines resulting in wines that are tasteless, fruity and less astringent after aging<ref> Scudamore-Smith PD, Hooper RL, McLaran ED (1990) Color and phenolic changes of Cabernet Sauvignon wine made by simultaneous yeast/bacterial fermentation and extended pomace contact. American Journal of Enology and Viticulture 41, 57-67 </ref>.  Oxidation reactions involving phenolics might also change the chemical and sensory profile of wines<ref> Bisson LF, Waterhouse AL, Ebeler SE, Walker MA, Lapsley JT (2002) The present and future of the international wine industry. Nature418, 696-699 </ref>.  Oxygen in the air is always ready to react with unprotected juice or wine and many of the substances present get adversely affected by oxidation, producing unpleasant, bitter, off-odours and off-tastes. However, it is recognized that some degree of oxygenation may be beneficial for the formation of red wine, but the quality of white wines is generally impaired by excessive air exposure. As tannins and anthocyanins interact with oxygen, which diffuses during barrel storage, these compounds further polymerize and become less astringent. Red wines become lighter in colour, and proanthocyanidins and other polyphenolics eventually aggregate in larger molecules which accumulate as sediment over time at the base of the bottle. In contrast, white wines often deepen in colour, turning darker honey colours as they oxidize andage <ref>sourcedfrom:http://www.academia.edu/8191054/Biochemical_Changes_throughout_Grape_Berry_Development_and_Fruit_and_Wine_Quality downloaded on 24/12/2016 </ref>.   
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''Navamadya''/fresh wine: New or fresh wines should not be consumed because they cause heaviness and create imbalances in all the three ''doshas'' while old wines promote circulation in the body, increase digestion, lightness and enhance taste in food. The effect of aging on tannins and resveratrol has been studied and shows significant difference between old and fresh wine. Aging results in altered and reduced phenolic contents in red wine. Anthocyanin tannin complexes can be formed which can stabilize the colour of red wines resulting in wines that are tasteless, fruity and less astringent after aging<ref> Scudamore-Smith PD, Hooper RL, McLaran ED (1990) Color and phenolic changes of Cabernet Sauvignon wine made by simultaneous yeast/bacterial fermentation and extended pomace contact. American Journal of Enology and Viticulture 41, 57-67 </ref>.  Oxidation reactions involving phenolics might also change the chemical and sensory profile of wines<ref> Bisson LF, Waterhouse AL, Ebeler SE, Walker MA, Lapsley JT (2002) The present and future of the international wine industry. Nature418, 696-699 </ref>.  Oxygen in the air is always ready to react with unprotected juice or wine and many of the substances present get adversely affected by oxidation, producing unpleasant, bitter, off-odours and off-tastes. However, it is recognized that some degree of oxygenation may be beneficial for the formation of red wine, but the quality of white wines is generally impaired by excessive air exposure. As tannins and anthocyanins interact with oxygen, which diffuses during barrel storage, these compounds further polymerize and become less astringent. Red wines become lighter in colour, and proanthocyanidins and other polyphenolics eventually aggregate in larger molecules which accumulate as sediment over time at the base of the bottle. In contrast, white wines often deepen in colour, turning darker honey colors as they oxidize and age <ref>sourcedfrom:http://www.academia.edu/8191054/Biochemical_Changes_throughout_Grape_Berry_Development_and_Fruit_and_Wine_Quality downloaded on 24/12/2016 </ref>.   
    
The phenolic compound present in a bottle of wine slowly changes as it ages. The most important component of wine is tannin which binds with proteins. High tannin containing wine inhibits saliva’s ability to lubricate mouth and imparts astringent feeling in mouth. Aged wine undergoes polymerization of tannins. This makes tannin sediments settle to the bottom of the container and lose its property to bind with proteins. Aged wines are very aromatic and possess fruity flavors.  
 
The phenolic compound present in a bottle of wine slowly changes as it ages. The most important component of wine is tannin which binds with proteins. High tannin containing wine inhibits saliva’s ability to lubricate mouth and imparts astringent feeling in mouth. Aged wine undergoes polymerization of tannins. This makes tannin sediments settle to the bottom of the container and lose its property to bind with proteins. Aged wines are very aromatic and possess fruity flavors.  

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