TAGATOSE-A PREBIOTIC OR A SWEETENER?

Food industry and the Pharmaceutical companies are continuously looking for newer non-calorie sweeteners with least harmful side effects and off taste. There are already half a dozen such sweeteners popular with weight watchers and diabetic people though each one of them cannot be considered as perfect in all respects. Latest to arrive is Tagatose a natural sugar obtained by isomerization of galactose under alkaline condition or through use of isomerase enzymes derived from yeast. It appears Tagatose occurs in small quantities in most dairy products though its presence is not felt by the consumer. As its sweetness index is 92 compared to 100 for cane sugar and its calories content is only 1.5 kC per gm lot of attention is being focused on this new sweetener. Though Tagatose is not produced commercially as of now, its emergence in future as a major player in low calorie foods cannot be ruled out. Here is a report on this natural sugar substitute.

"It's not quite as sweet as table sugar, but it's very close. It works well in baked goods and beverages for sweetening, but it hasn't become common yet. Besides the food industry, tagatose has caught the interest of medical researchers for a couple of reasons. One is that we don't absorb it very well. That means that we don't get as many calories from tagatose as we do from fructose or glucose — only about half as many. And if we don't absorb it, it doesn't have as much effect on our blood sugar. So it has been getting some interest for use in weight-control foods and for people with diabetes. The other effect of not being absorbed is that when it gets farther down in our gut, the friendly bacteria can use it. So some producers are trying to promote it as a prebiotic, something to help the good gut bacteria grow better. The flip side of that is that bacteria produce gas when they grow. Some people have found that eating foods sweetened with tagatose gives them gas, bloating, stomach rumbles and even diarrhea. As with many dietary fibers that are also prebiotics, the effects depend on the dose. Eat a lot and you're more likely to feel an effect than eating just a little bit. Yogurt doesn't bother most people, and neither does tagatose. It's not commonly used yet, but don't be surprised if it starts to appear in more and more foods".

Tagatose is not absorbed across the intestinal wall and hence passes into large intestine with no calorie effect in the blood. But it has been pointed out that the Tagatose molecules can be physically transported across the intestine, eventually getting into the blood though in relatively small concentrations. Without adequate safety studies and enough understanding of its metabolism once it enters the blood stream, its universal use should not be permitted. As its sweetness is only 92% that of sugar, large amounts are needed to perceive the sweetness effect and with average consumption of 75 gm of sugar by an individual Tagatose can never be an alternate sugar substitute unless its consumption at high levels is proved safe. Of course cost is another factor which may come in the way of commercializing this new sweetener. Since it has been approved as a GRAS ingredient in the US in 2001, food industry may still try it out for special applications. Probably use of Tagatose as a base for carrying other sweeteners like Aspartame, Sucralose, Stevia etc may be more feasible.  

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

PREBIOTICS FOR PROTECTION OF PROBIOTICS-NEW INSIGHT INTO THEIR SYNERGY

Probiotic microorganisms are promoted in a big way by the food industry with wide ranging claims regarding the benefits flowing out of consuming foods containing these bacteria regularly. It is true that the GI tract in human beings houses more than 500 strains of microbes, some considered good while a few can be pathogenic to varying extent. Delivering probiotic bugs to the intestinal area through food poses some logistical problems because of high acidic content of the stomach juice that can kill them. Probably the resident organisms that colonize the gut can multiply their number if substrates like milk and derived products are consumed abundantly and frequently. Freeze dried culture encapsulated for protection against stomach acidity is often resorted to under rehabilitation regime, especially after consumption of antibiotic medicines. The present trend in designing non-dairy products with high bacterial density capitalizes on the ability of the fiber to protect the live cells while traversing through the hostile environment in the stomach

"The growing interest in healthy food has widened the scope for probiotics. However, the viability of probiotic products in the food matrix depends both on the strain used and the characteristics of the food itself. The introduction of probiotic cultures into non-dairy products therefore remains a challenge for the functional food industry. The use of prebiotics, which selectively stimulate the growth of one or more bacteria in the colon, may facilitate the incorporation of probiotics into such foods. Food fibres consist of non-starch polysaccharides and are widely found in fruit, vegetables, cereals and legumes. Fibres can help reduce blood pressure, improve serum cholesterol levels and intestinal functions, and control weight. Some fibres also have prebiotic effects. Synbiotic products, which contain both probiotic and prebiotic ingredients, may increase the survival of probiotic bacteria under gastrointestinal conditions and help protect the probiotic during freeze drying".

Dietary fiber has other roles also as mentioned above and thousands of foods are now being formulated containing fiber from a variety of sources like fruits, vegetables, food grains and others. There are some species of bacteria that converts part of the dietary fiber into nutrients like vitamins, amino acids and essential fatty acids making them truly prebiotic substances of immense value to maintain good health. Where the industry is going wrong is making tall claims about the effect of probiotics forcing food safety authorities in the EU to come down heavily on such practices and health claims if and when made must be substantiated by scientific evidence. Consumers can heave a sigh of relief if products with dubious claims are weeded out of the market.

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com