It has been found that probiotic-fermented carrot pulp has a beneficial effect in reducing blood glucose, more so than unfermented pulp. This paper explores the reason for this by looking at fermentation-induced changes in nutritional components and hypoglycemic effects of its polysaccharides. Micronutrient content showed minor changes, except for titratable acidity. Fat and protein decreased, while total carbohydrates increased. These polysaccharides are pectinic, and the number of total polysaccharides rose after fermentation. Scanning electron microscopy showed that the morphology changed from filamentous solid to spiral. The molecular weight of water-soluble polysaccharide (WSP) diminished after fermentation, while those of acid- and alkali-soluble polysaccharides increased. WSP had stronger hydroxyl radical scavenging activity in vitro, and WSP from probiotic-fermented carrot pulps showed better hypoglycemic effects than WSP from non-fermented carrot pulps in animal experiments. Thus, the fermentation-induced improvement in diabetes control from fermented carrot pulp probably arises from its WSP.
Keywords: carrot; diabetes; nutritional component; polysaccharides; probiotics fermentation; structural characteristic.