Guest Bee Keeper Posted May 4, 2010 Report Share Posted May 4, 2010 In the United States, high-fructose corn syrup (HFCS) has become a sucrose replacement for honey bees and has widespread use as a sweetener in many processed foods and beverages for human consumption. It is utilized by commercial beekeepers as a food for honey bees for several reasons: to promote brood production, after bees have been moved for commercial pollination, and when field-gathered nectar sources are scarce. Hydroxymethylfurfural (HMF) is a heat-formed contaminant and is the most noted toxin to honey bees. Currently, there are no rapid field tests that would alert beekeepers of dangerous levels of HMF in HFCS or honey. In this study, the initial levels and the rates of formation of HMF at four temperatures were evaluated in U.S.-available HFCS samples. Different HFCS brands were analyzed and compared for acidity and metal ions by inductively coupled plasma mass spectroscopy. Levels of HMF in eight HFCS products were evaluated over 35 days, and the data were fit to polynomial and exponential equations, with excellent correlations. The data can be used by beekeepers to predict HMF formation on storage. Caged bee studies were conducted to evaluate the HMF dose-response effect on bee mortality. Finally, commercial bases such as lime, potash, and caustic soda were added to neutralize hydronium ion in HMF samples, and the rates of HMF formation were compared at 45 degrees C. Obesity is a growing problem. In the broadest strokes, it is due to a small positive energy balance that persists over a sufficiently long time. Some forms of obesity develop independent of the type of diet that is eaten, whereas others are dependent on the diet. Among the former are individuals with leptin deficiency or genetic defects in the melanocortin 4 receptor. Most human obesity, however, occurs in the presence of highly palatable foods--fat and calorically sweetened beverages. The increase in obesity in the last 35 years has paralleled the increasing use of high-fructose corn syrup (HFCS), which first appeared just before 1970. Current soft drinks and many other foods are sweetened with this product because it is inexpensive and has useful manufacturing properties. The fructose in HFCS and sugar makes beverages very sweet, and this sweetness may underlie the relation of obesity to soft drink consumption. Fructose consumption has also been related to the metabolic syndrome and to abnormal lipid patterns. This evidence suggests that we should worry about our current level of fructose consumption, which has been increasing steadily for over 200 years and now represents over 10% of the energy intake of some people. HFCS now represents > 40% of caloric sweeteners added to foods and beverages and is the sole caloric sweetener in soft drinks in the United States. Our most conservative estimate of the consumption of HFCS indicates a daily average of 132 kcal for all Americans aged > or = 2 y, and the top 20% of consumers of caloric sweeteners ingest 316 kcal from HFCS/d. The increased use of HFCS in the United States mirrors the rapid increase in obesity. The digestion, absorption, and metabolism of fructose differ from those of glucose. Hepatic metabolism of fructose favors de novo lipogenesis. In addition, unlike glucose, fructose does not stimulate insulin secretion or enhance leptin production. Because insulin and leptin act as key afferent signals in the regulation of food intake and body weight, this suggests that dietary fructose may contribute to increased energy intake and weight gain. Furthermore, calorically sweetened beverages may enhance caloric overconsumption. Thus, the increase in consumption of HFCS has a temporal relation to the epidemic of obesity, and the overconsumption of HFCS in calorically sweetened beverages may play a role in the epidemic of obesity. Quote Link to comment Share on other sites More sharing options...
Guest Andrea Posted May 4, 2010 Report Share Posted May 4, 2010 A German study showed that bees fed on pollen from genetically-modified, insect-resistant crops were significantly more vulnerable to population collapse when infested by parasites than bees fed on normal crops. The practice of feeding corn syrup derived from genetically-modified maize to bees during winter months is likely to exacerbate this situation. Quote Link to comment Share on other sites More sharing options...
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