Why carbohydrate did not give a positive result?
Let us first look at the simple chemistry of Benedict's reagent: It contains blue copper 2+ ion which is reduced to red copper1+ oxide by sugars(carbohydrates) when its treated with a carbohydrate.This is actually done by aldehyde and keto groups present in carbohydrates (such carbohydrates with these groups are called Reducing Sugars). During this reducing reaction, the keto and aldehyde ends of these reducing sugars get oxidized themselves to carboxylic groups.The copper oxide(1+) is insoluble in water and so precipitates and renders the colour to the solution. The color of the final solution ranges from green to brick red depending on how many of the copper ions are present. On boiling a sugar with acids like HCL or H2SO4, you are actually dehydrating the carbohydrate. The water from the sugar is lost and you get what is called a "Furfural derivative" Thus your Benedict's reagent fails to give a reactrion with them. Additional info: (this might help in your exam) If such an acid-treated carbohydrate is then treated with "alpha naphthol" or "thymol" or "resorcinol", you can get coloured condensation precipitates. This is the basis of several other tests like "Molisch test" "seliwanoff's test " etc. Hope that's useful ! Bye.
Fat is a more efficient store of energy than carbohydrate. Which of the following is NOT a factor in this?
Fat is a more efficient store of energy than carbohydrate. Which of the following is NOT a factor in this? Carbohydrates are polar, hydrophilic molecules. Fat is catabolized only aerobically; carbohydrate can be catabolized anaerobically. Fatty acids are more highly reduced than carbohydrates. Per gram, fatty acids contain twice as many calories as glucose.
Why are reducing and non-reducing ends of sugars named so?
sugar molecules combine with each other with a glycosidic linkage or bond. a linkage between C-1 of one monosaccaride (monomer sugar) unit and C-4 of another is called 1,4 linkage and if this linkage is between two hydrfoxyl groups in alpha position is called alpha 1,4 linkage. Likewise there is beta linkage. this bond is formed when hydroxyl group on one sugar reacts with the anomeric carbon on other. when an anomeric carbon is involved in glycosidic bond, it cannot be oxidized by cupric or ferric ion. this end called non reducing sugar end.
When people say reduce carbs could that mean not eating rice if you eat a lot of rice? Does rice have a lot of carbs?
"Reducing carbs" means dramatically reducing or eliminating from your diet in the short-term, all forms of refined and/or high-glycemic carbohydrates, including rice, potatoes, wheat, tapioca, cous cous, bread (especially white bread), sugar and foods that contain sugar, corn syrup and foods containing it (e.g. condiments, instant soup, instant sauces), glucose, dextrose, fructose and foods containing these. All carbohydrates have both a glycemic index, and a glycemic load. Glycemic index is defined as "a figure representing the relative ability of a carbohydrate food to increase the level of glucose in the blood". Essentially, it refers to the molecular structure of the sugar molecule and how easily digestible it is. Glucose has a glycemic load of 100, is digested instantly, and it is used as the bench-mark standard for other foods.Glycemic load is "the theoretical cumulative exposure to glycemia over a period of time and is derived as glycemic index × carbohydrate intake." In other words, glycemic load refers to the glycemic content of the food itself, i.e. how heavily loaded the food is with sugar or starch, and the portion size.For example, watermelon has a very glycemic index, but a low glycemic load. You would be eating a high-glycemic carbohydrate, but it wouldn't result in fat gain. While the sugar in watermelon has a high GI, it contains a relatively small load of it, because watermelon is mostly water.A rice dish, on the other hand, can be converted to a low- or a medium-glycemic food, provided that one ate brown rice with a lot of roughage and protein, and mixed in low-glycemic starches like lentils and split beans. Adding plant oils to the rice further reduces the glycemic index. You would feel fuller for longer, and you would have fewer carb cravings and hence would be less inclined to snack. However, if you ate this often you would nonetheless gain weight, because all rice -- whether brown or white -- packs a high glycemic load.
How do I determine if a compound is a reducing sugar?
all those carbohydrates which contain aldehydic or ketonic group in hemiacetal or hemiketal form and reduce tollen's reagent or fehling's solution are called reducing carbohydrates or sugars....while others which do not reduce these reagents are called non reducing sugars....all monosaccharides whether aldoses or ketoses are reducing sugars...diasaccharide such as sucrose in which the two monosaccharide units are linked through their reducing centres,i.e. aldehydic or ketonic group are non reducing while others in which these groups are in hemiacetal or hemiketal form are reducing sugars..maltose is a reducing sugar.....however all polysaccharides(for ex-starch,cellulose,glycogen,dextrins etc) are non-reducing sugars... Both maltose and cellobiose are reducing sugars because the anomeric carbons on the right-hand sugar are part of a hemiacetal.... see this link-- http://www.ausetute.com.au/redsugar.html
What is the difference between reducing and non-reducing sugars? How can you identify the difference between the 2 of them?
Thanks for A2A.Any carbohydrate which is capable of being oxidized and causes the reduction of other substances without having to be hydrolysed first is known as reducing sugar, but those which are unable to be oxidised and do not reduce other substances are known as non-reducing sugars. Generally, all the free monosaccharides having free aldehyde or hydroxyl ketonic group are capable of being oxidised. After being oxidised they cause the reduction of the other substances and so known as reducing sugars.Fehling’s solution and Benedict’s solution are carry out the oxidation e.g.,Reducing carbohydrate + Fehling’s solution (Deep blue) -> Oxidised Carbohydrates + 2 Cu+2Cu+ + 2OH -> 2CuOH (Light yellow or green) -> Cu2O (Red) + H2OC6H12O6 (Glucose) + 2Cu(OH)2-> C6H12O7 (Gluconic acid) + Cu2O (Red) + H2ODifferences between reducing and non-reducing sugars are:Reducing1. Possess a free aldehyde(-CHO) or ketone (-C=0) Group.2. Can reduce the Cu2+ cupric ions (blue)in Fehling’s or Benedict’s Solution to Cu+ cuprous ions (reddish) that precipitate out as Cu2O(cuprous oxide).3. Maltose. lactose, melibiose, gentiobiose, cellobiose, mannotriose, rhamnotriose.Non-reducing1. A free aldehyde or ketonic group is lacking.2. No such reaction.3. Sucrose, trehalose,raffinose, gentiarose, melezitose. I hope it will help.
What are reducing and non-reducing sugars?
Sugar is a type of carbohydrate. There are many different types of sugars. Some sugars are simple sugars with a simple structure. They are known as monosaccharides. Some common examples for monosaccharides include glucose, fructose, and galactose. Some sugars are formed by the bonding of two monosaccharides. They are known as disaccharides. Some common disaccharides are sucrose, maltose, and lactose. What we use as table sugar is obtained from plants such as sugar cane. Sugars can be divided into two groups depending on their chemical behaviors: reducing sugars and nonreducing sugars. The main difference between reducing and nonreducing sugar is that reducing sugars have free aldehyde or ketone groups whereas nonreducing sugars do not have free aldehyde or ketone groups.Reducing sugars are carbohydrates that can act as reducing agents due to the presence of free aldehyde groups or free ketone groups. These are sugars because this group of compounds has a sweet taste as other sugars. All monosaccharides and some disaccharides are reducing sugars.Reducing sugars can be oxidized by weak oxidizing agents. In aqueous medium, reducing sugars generate one or more compounds containing an aldehyde group. This is a characteristics property of reducing sugars. Examples of reducing sugars include glucose, fructose, galactose as monosaccharides and lactose, maltose as disaccharides.Nonreducing sugars are carbohydrates that cannot act as reducing agents due to the absence of free aldehyde groups or free ketone groups. Some disaccharides and all polysaccharides are reducing sugars. In basic aqueous media, nonreducing sugars do not generate any compounds containing an aldehyde group.
Does reducing carbs intake instead of outright eliminating them help lose weight?
Low carb diets work because carbs are "easy energy" and the body is a very efficient machine. Proteins and fats actually use more energy (calories) to digest and store than you get from them- it's pretty simple physics.So if you cut carbs- especially simple carbs- your body is using calories to get fewer calories. That's why low-carb diets "work".But, there's a downside, and you've run into it: The body WANTS carbs. The body is efficient- it wants to STORE energy, not use it to get even less energy. So if you sneak in a few extra carbs, the body's going to store them- after all, as far as the body's concerned, you've been starving it! The more carbs you eat, the more the energy the body stores. And stored energy is adipose tissue- or fat.If you do not have the will-power to stick to a very low-carb diet (and, personally, who would want to??) simply stop eating crazily and start eating sensibly.Determine your caloric need: How Many Calories Do I Need?(Don't cheat and say you're very energetic because you plan on starting to exercise; be honest so you succeed).Learn about portion control: http://www.mayoclinic.com/health...Divide your calories into 6 small meals daily, taking in the majority of your calories before late afternoon.Increase your intake of waterAvoid artificial sweeteners; they actually cause the munchies. Jae Starr's answer to I am a freelance computer programmer and I am constantly munching on something as I work from home. What foods can I eat in 'unlimited' quantities without putting on weight?Walk. Walk walk walk walk. 2 miles in 30 minutes- everyone has 30 minutes.
What is the best rice to eat if you should reduce carb intake?
When it comes to weight loss, the first thing that always come to our mind is to start avoiding rice in our daily diet. We always keep lingering over the same question – Is rice fattening? Well the answer to that question depends upon the kind of rice you opt for in your daily diet.There are different types of rice which have different nutritional functionalities, but the rice that is essentially the most helpful in weight loss and has numerous health benefit brown rice.But to actually understand why we say that we need to understand some basics like-Nutritional difference of the various types of rice availableMore facts about riceRice and its fattening reality.Nutritional Value and FactsA. White long grained riceCalories (one cup of cooked rice, 158 gm)= 206 kcal.Type of cooking=When boiled or steamed, white rice contains less than 0.5g fat.Proteins content=4.3gMost important: but unlike proteins from animal products or meat, the protein of rice lacks a wholesome amount of amino acids and hence for full nutritional benefit should be eaten in combination with an animal or a plant derived protein.Carbohydrates=53 g, which is actually 18% of our recommended* daily carbohydrate intake.The dietary fibre =is < 1g per serving.Full of vitamins and minerals such as folate, thiamine, niacin, iron and selenium. These play a highly important role in maintaining a healthy body.RELATED ARTICLES:"20 Secret tips to lose belly fat fast""20 most annoying things that people do in a gym""20 Open Secret Weight Loss Diet""20 Most Important Habits For Eating Healthy And Losing Weight""20 Proven Ways to Motivate Yourself to Go to the Gym"
How many carbs should I eat to reduce belly fat and not loose muscle mass?
The recommended carbohydrate intake for the general population is 45–65% of your daily caloric intake.Specifically, below is the recommendation taken from The 2010 Dietary Guidelines for Americans:Carbohydrates: 45-65% of caloriesFat: 20-35% of caloriesProtein: 10-35% of caloriesFor a more exact ratio for weight loss purposes, I recommend the lower end for both carbs and fat: 50% carbs, 15% fat, and at least 35% protein.With that said, there are many low-carb diet programs that recommend as little as 5% carbohydrates, such as the Keto Diet or the Atkins Diet. You are welcome to do your own research on this matter, and decide whether they are right for you.My two cents: Be wary of programs that suggest eliminating or severely limiting carbohydrate or fat from your diet. Both of these macronutrients are essential to the way our body function, and there are plenty of healthy sources for both. Good sources of fat include avocados; olives; nuts; peanut butter; walnuts; tofu; sunflower, sesame, flax, and pumpkin seeds; and fatty fish like salmon, tuna, mackerel, and herring. Good sources of carbohydrates include vegetables, whole fruits and grains, legumes, nuts, seeds, and potatoes.WHAT ABOUT REST AND TRAINING TO PREVENT MUSCLE LOSS?Of course, rest is important. After all, most of the protein synthesis in your body takes place during sleep. Studies have proven that insufficient sleep is related to a number of factors that impair hypertrophy.One particular study found that when 10 men reduced their amount of sleep from 9 to 5 hours their testosterone levels dropped by up to 14% during the day. To make matters worse, a lack of sufficient sleep also hinders fat loss effortsThe basic idea behind training is still the same, cutting or not: Train hard, strive for progressive overload or at least strength maintenance, and do High Intensity Interval Training for cardio.Since you may be a little low on energy when in a caloric deficit, I recommend you focus on compound movements to get the biggest bang for your buck.Good luck :)