Calories or calories??

There are millions of people for whom it is almost impossible to arrange two square meals for the families. So they don’t have any choice of what they eat. On the other hand, there are affluent people for whom what to eat or what not to eat is a big problem. They are grappling with obesity problems which are the precursor of so many lethal ailments like heart attack, blood pressure, backache and diabetes. They are always conscious of the calorific value of the foods they consume.

Any student of science or health conscious person is aware that calorie is unit of energy. Our bodies continuously require energy to properly perform normal functions of the body. Even while doing nothing, our body consumes energy called basal metabolic rate.

Calorie and calorie are slightly different. In nutrition science, Calorie with capital C is equal to 1000 calories. Sometimes, Calorie is also called kilo calorie. 1 Calorie is the amount of energy it takes to raise 1 kilogram of water 1 degree centigrade at sea level.

The calorie content of foods consumed  by a human being was determined in the late 1800s by Wilbur O. Atwater, an agricultural chemist. He built a device called a “Respiration Calorimeter” to make direct measurements of heat released by humans from the food they consumed. At 4 feet by 8 feet, Atwater’s calorimeter was big enough to allow a person to step into it. The device measured the amount of heat released by that person, along with the amount of oxygen consumed and carbon dioxide given off.

Wilbur Olin Atwater
Wilbur Olin Atwater (Photo credit: Wikipedia)

Using this device, Atwater was able to measure the precise amount of energy contained in thousands of food items. He found that carbohydrates and proteins are worth 4 Calories per gram and fats about 9 Calories per gram. This 4-9-4 system is how labels are determined today. In some cases, dietary fiber is subtracted from the total carbohydrate count because it is assumed that it provides no nutritional calories. Also, alcohol, if present, is accounted for as 7 Calories per gram.

Basal metabolism reactions occurring inside our bodies consume 70% of the calories. Rest 30% if not consumed shall be deposited in the body mostly in the form of fat.

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Wasabi: The Real Stuff is in short supply

There is a Wasabi restaurant in Taj Hotel in Bombay. We can never afford to go to such hotels but heard the name in context of the terrorist attack on the hotel. Actually Wasabi is root stem like ginger and its name is Wasabia Japonica. All this indicates that the whole thing is about Japanese food especially Sushi. Wasabi is used as one of the ingredients in the form of paste of pistachio-green color. It adds the zing to the food.

The real thing is in the short supply even in Japan its home itself.  So at most places what is served as wasabi paste is most likely just a mix of European horseradish, mustard, and food coloring.

As a member of the Cruciferae family, it is related to such plants as cabbage, cauliflower, broccoli, and mustard. Its distant cousin European horseradish (Armoracia rusticana) often substitutes for it.

Wasabi grows naturally in mountain streambeds, and the Japanese have cultivated it for more than a millennium. Wasabi grown in semiaquatic conditions is known as sawa, whereas wasabi grown in fields is called oka. The stream-grown wasabi produces larger rhizomes and is generally considered to be of higher quality.

The heat of real Wasabi lasts at the most for 15 minutes after grating. But its imitations like horseradish stays for long periods. The components of both wasabi and horseradish can be stabilized by acids, such as vinegar or lemon juice.

The key chemicals that give wasabi its characteristic heat and flavor aren’t present until the wasabi is macerated. When the cell wall is disrupted, it releases the enzyme myrosinase, which hydrolyzes glucosinolates, a group of sulfur-containing glucose derivatives, to produce isothiocyanates that provide wasabi’s spicy zing. The most abundant of these is allyl isothiocyanate. Horseradish has a different profile of isothiocyanates. One of the by-products of the myrosinase reaction is glucose.

The flavor is affected by how finely the wasabi is grated. The traditional way to grate wasabi is with a sharkskin grater, called an oroshi, which resembles fine sandpaper. Because the flavor and heat dissipate so rapidly, it’s best to grate it as you need it.

Scientific studies carried out by Savage and his coworkers show comparison of seven isothiocyanates in wasabi and horseradish. The horseradish contained 1.9 g total isothiocyanate/kg, whereas wasabi contained nearly 10% more (2.1 g/kg). Allyl isothiocyanate was the major component in both. The second most abundant isothiocyanate was 2-phenylethyl isothiocyanate, but it was found only in the horseradish. It, therefore, probably plays a major role in the flavor differences between the two plants. Every other isothiocyanate was present at higher concentrations in wasabi than in horseradish.

Honey: A Food fit for Gods

Honey is thought to be very healthy sweetener. It is produced by bees as their food source and made from nectar sucked from the flowers with the help of enzymes. The final product is made of roughly 80% sugar, 17% water and a number of trace compounds. It is these trace compounds that are responsible for honey’s varied flavors and colors. The most abundant sugars in honey are fructose and glucose. Among the myriad minor complex sugars in the honey are maltose, sucrose, and other disaccharides, as well as trisaccharides such as erlose.

The nectar is mixed with enzymes, Invertase being the most critical, in their stomach-like honey sacs. Invertase splits the sucrose in the nectar into fructose and glucose and also produces some erlose. Back at the hive, the bees pass the digested material to house bees who reduce the moisture content of the mixture by ingesting and regurgitating it. They then deposit concentrated drops into honeycomb cells. Over the next few days, bees fan the fluid with their wings to further concentrate it, and finally, they cap the cells with wax. At the same time, enzyme-mediated changes produce a range of sugars and acids in the honey. Bee enzymes also show up in the finished product. Another enzyme, glucose oxidase, converts glucose to gluconolactone, which is then hydrolyzed to give gluconic acid, the principal acid in honey. Formic, acetic, butyric, and lactic acids are also found in honey, which explains why its pH typically measures 3.8-4.0 which is quite acidic and inhibits the growth of any bacteria in it.

Honey also contains small amounts of minerals and proteins. About 0.2% of honey is ash, probably originating in the flower nectar. Potassium accounts for about one-third of the ash. Other trace elements in honey include iron, manganese, copper, and silicon. The sweetener also contains up to 1% nitrogen, which comes principally from proteins. These proteins can cause honey to foam and form tiny air bubbles.

Of the more than 100 compounds found in honey, many are volatile organic compounds, such as phenylethyl alcohol, that contribute to flavor. The honey flavor is dependent on the flavor compounds and aroma compounds that come from a flower.

Because weather and geography affect flowers, each batch of honey can have a slightly different makeup of flavor chemicals.

Plants are very Smart Indeed

Plants are very smart, efficient and unforgiving in the energy management. Unlike the animals, who cannot regrow their limbs, plants see to it that inefficient leaves are cast off and replaced by new efficient one’s so that the food making machine continue to run smoothly. The leaves make the food by combining carbon dioxide and water in the presence of chlorophyll which shepherds the energy from sun and store it in the plant. Animals make use of this energy by eating the plant parts. This pigment imparts green color to the leaves and masks the faint colors of other chemicals like caroteneoids.

As soon as, the plant know that the a given leaf is under performing, it gradually decrease the supply of chlorophyll and also reclaims whatever it can of the other components. Gradually the color of leaf begins to become yellowish and it looses it strength and fall off the branch. Older leaves are constantly replenished and plant continues to make its food.

When the winter comes, the Sun is hardly visible because sky is mostly overcast. So the plants plan to shut down the food making factories. They withdraw the chlorophyll from the leaves and like polar bears go into a state of hibernation. Leaves acquire beautiful brown, reddish and yellowish hues due to the waning of the effect of chlorophyll. As the winter recedes, Sun comes out, the food making is resumed.

Hummingbirds: The extraordinary birds

Hummingbirds are most beautiful birds endowed with dazzling colors and hues. But these birds seem to be consigned to the extreme life because at the end of the day, they are so exhausted that it is not sure whether or not they will live to see the another day. Their humming near the flowers in which they insert their specialized beaks to suck the nectar while steadying themselves by constantly flapping their wings, seems like a fluid motion poetry. It is sight to behold. They can fly forward and backward, up and down manoeuvrings come as easily to them.

So they are not the ordinary birds but take the definition of extraordinary to a whole new level. They are the smallest warm-blooded creatures on the planet, but they are also among the fastest. They measure on the average 4-5 centimeters. They can  With wings that beat up to 200 times every second, they are among nature’s most accomplished athletes, the only birds able to hover, fly backwards, and even upside down.

Hummingbird metabolisms are set in permanent overdrive, requiring them to consume more than half their body weight in nectar every day. Some researchers say that nectar consumption for providing energy to fuel the furious activity during the day time, may be equal to their own weights. Since nectar provides them only sugars for energy, they have to supplement it with insects for getting proteins and other nutrients.

To survive the night, they fluff up their feathers and adjust their body thermostats, and reduce their body temperatures by half and reduce their heart rate from 600 beats per minute to a mere 36 to save the energy for survival  and begin their struggle for life next morning.

Due to their small size and dizzying speeds, human beings know only the crude facets of their sizes. PBS has sponsored a study to peer closely into their lives. By using state of the art technology and high definiton cameras, they have been able to delve deep into the private lives of hummingbirds. With  cameras able to capture over 500 images a second, the hummingbirds’ magical world can finally be seen and appreciated. Amazing footage shows these little powerhouses are far more than delicate nectar gatherers — they are also deadly predators. And watch as the birds display their elaborate mating rituals, showing off with nose dives that subject them to over ten G’s of force — enough to cause an experienced fighter pilot to black out!

These tiny marvels dazzle and delight bird watchers all over the world, and NATURE reveals their stunning abilities as they have never been seen before. The whole story is available at the PBS website page. Please go through and if you can watch the video you are lucky because video is blocked in our region, God knows for whatever reasons.

Slow Food Movement & Navdanya

The world, especially in the cities, is becoming a busy place. The system of joint families exist now largely in the villages. As more and more people are becoming qualified, they migrate towards the cities where their education  can earn them a good living. As the cities are becoming overcrowded, the cost of living increases and ultimately migrants are not in much better condition than they were at the native places.

The life has become so much hectic in the cities that the food for which we all are toiling day and night has taken a back seat in the list of preferences of human beings. The people are always in a rush. You can easily figure out children munching pieces of bread, apple or chocolates on their way to school. In India, food is linked with pious and religious feelings and is partaken after thanksgiving. Hands and face are washed before taking the food. Members present in the house prefer to sit on the mats on cleaned floor and see to it that they eat together. All this is changing rapidly due to the fact that more and more members of the family are employed somewhere and their schedules are different. People don’t enjoy their food. Some eat it while walking or doing office work.

Due to this, it  has become a world of fast food. The foods which are available within a few minutes after ordering. These are generally addictive type of foods because they appeal to taste buds. They are very high in fat and other harmful ingredients and contribute a great deal in the problem of obesity. The concept of fast food also means eating out. Eating out the bad food at a very cost. Results of all this become apparent when health problems like stress, obesity, blood problem and diabetes occur at an early age.

Many groups of people are making efforts to reverse this pernicious trend. One such movement is Slow Food movement. It was started by Carlo Petrini in 1986 in Italy. This movement strives to preserve tradition and regional cuisine of a region. It encourages the residents to preserve and grow the local varieties of seeds. The movement has since expanded globally to over 100,000 members in 132 countries. Its goals of sustainable foods and promotion of local small businesses are paralleled by a political agenda directed against globalization of agricultural products.

In India, efforts are on to hark back to good old days and traditions followed in those days. One such movement is Navdanya (nine seeds) movement. It has been started by Dr. Vandana Shiva, in Dehradun. Dr.Shiva has analyzed in depth the green revolution in Punjab which ushered the country into self dependence in foodgrains. She has concluded that examined in the broader and long time context, it has done more harm to the land of state than the benefit. Results are indicating it to be true. Green revolution crops used single strains of seeds which necessiated the need of using very high quantities of insecticides. They also high amounts of fertilizers and water.

Results are not a happy augury. Water table has gone down. High amount of dangerous contaminants have seeped into the earth and underground water causing high instances of diseases like cancer. Even the vegetables and grains contain high amount of banned insecticides and pesticides. Ultimate cost the nation is going to pay is very high. It is another matter that whatever our elders sowed has to be eaten by the coming generations. The biggest culprit in this fiasco is the government which has closed their eyes to the use of dangerous pesticides. The others are agriculture Universities because it is these universities which teach the illiterate farmers.

Navdanya movement strives to preserve and multiply the local seed varieties. In fact, it has successfully saved the many varieties from extinction. In nutshell, the strategy is to sow mixed crops. Such crops are less prone to be affected en-masse and in fact grow successfully utilizing the different nutrients from the soil. The fertilizers are dung manure and pesticides are prepared from the leaves of trees like neem. The movement has revived the organic farming in the region.

Pavlovian Conditioning

Sometimes, a discovery seems too simple to believe its applications. This is the case with Pavlovian conditioning named after the doctor Ivan Pavlov. He was a doctor and besides his research  on the secrets of digestive system, he was interested in knowing what signals triggered the related phenomena such as secretion of saliva.

We know that saliva is secreted whenever food is presented before animals. This is called drooling. In us humans, an enzyme called Amylase is present in the saliva which breaks down the starch we eat into lower sugars which are sources of energy for sustaining our bodies. Similarly, dogs begin to drool whenever food is presented before them. But what strange thing he observed was that dog also began to drool whenever it saw the doctor’s coat. He concluded that dog formed an association with lab coat and associated it with food. He did more experiment of different kind. He will ring a bell and immediately present food to dog. After some days, he observed that dog began to secret saliva on ringing the bell even if he was not presented with food. This time dog has formed an association between ringing of bell and presentation of food. Pavlov’s discovery was that the environmental events that previously had no relation to a given reflex (such as a bell sound) could, through experience, can be made to trigger a reflex (salivation). This kind of learnt response is called conditioned reflex, and the process whereby dogs or humans learn to connect a stimulus to a reflex is called conditioning.

Animals generally learn to associate stimuli that are relevant to their survival. Food aversion is an example of a natural conditioned reflex. If an animal eats something with a distinctive vanilla taste and then eats a tasteless poison that leads to nausea, the animal will not be particularly eager to eat vanilla-flavoured food the next time. Linking nausea to taste is an evolutionarily successful strategy, since animals that failed to learn their lesson did not last very long.

This work has great spin off studies and changing of behavior.  An important principle in conditioned learning is that an established conditioned response (salivating in the case of the dogs) decreases in intensity if the conditioned stimulus (bell) is repeatedly presented without the unconditioned stimulus (food). This process is called extinction.

In order to treat phobias evoked by certain environmental situations, such as heights or crowds, this phenomenon can be used. The patient is first taught a muscle relaxation technique. Then he or she is told , over a period of days, to imagine the fear-producing situation while trying to inhibit the anxiety by relaxation. At the end of the series, the strongest anxiety-provoking situation may be brought to mind without anxiety. This process is called systematic desensitization.

Pavlovian conditioning is used in effective commercial advertising.  An effective commercial should be able to manipulate the response to a stimulus (like seeing a product’s name) which initially does not provoke any feeling. The objective is to train people to make the “false” connection between positive emotions (e.g. happiness or feeling attractive) and the particular brand of consumer goods being advertised.