FOS are receiving attention and importance not merely because of their application as alternative sweeteners but rather for the accompanied desirable characteristics. The earlier known health benefits of FOS were inhibitory effect on pathogens and stimulatory effect on Bifidobacterium. The FOS was analyzed further to highlight its detailed interaction with Bifidobacterium (probiotics) which paved a pathway for the concept of synbiotics (Perrin et al. 2001; Vander et al. 2004). The health benefits of FOS have been reviewed by many workers (Antosova and Polakovic 2001; Hernandez et al. 2009; Patel and Goyal 2011; Ganaje et al. 2014).

Some of the evident health benefits observed by consumption of fructooligosaccharides include the following:

Promotes growth of the gut micro flora

Studies on Bifidobacterium species revealed that fructooligosaccharides preferred those carbohydrates which allow maximum growth and metabolic activities of this beneficial flora in human intestine (Palframan et al. 2003). The diet and its composition have an impact on gut and its microflora. It has been observed that any kind of change in the diet affects the metabolism of the inhabitants. The dietary fibres like oligosaccharides exert a combined effect on both the pH environment of the gut and the metabolism of bacterial community (Chen et al. 2000; Flint et al. 2007).

Prebiotics have multidimensional effect on host-bacteria interaction

It is now well established fact that host bacteria interactions are highly specific with varied dimensions. The digestion resistant carbohydrates in the gut are fermented in the colon which causes increase in the serum lactate levels. The study was conducted on horses by injecting fructooligosaccharides directly in caecum and acidotic state was maintained. Its effect on caecum bacteria and metabolites were analyzed. Streptococcal species (EHSS) showed positive relation with caecum lactate and negative response with serum lactate; however, serum lactate has a positive influence on Enterobacteriaceae (Rudi 2010).

Genetic features direct the probiotic effect of bacteria

Excellent studies on genomics of lactic acid bacteria in relation to their role in functional foods have been done by Klaenhammer et al. (2005). Their findings discovered that many genetic features exert control over the bacterial metabolic and probiotic process.

Development of resistance to ill effects of bile salts

Fructooligosaccharides and their monomeric derivatives offer resistance against the ill effects of bile salts on Bifidus group of intestinal inhabitants. Perrin et al. (2001) studied the inhibitory effect of bile salts on three strains of Bifidobacterium in medium containing any carbohydrate source. In presence of fructooligosaccharides in the medium the Bifidobacterium improved their resistance and demonstrated better growth in presence of bile salts. Macfarlane et al. (2008) studied the effect of inulo, galacto and fructooligosaccharides was extremely favorable for Bifidobacterium and also Lactobacilli but to a lesser extent. Their health benefits encompass features like putative anti-cancer properties, mineral absorption, lipid metabolism, anti-inflammatory and other immune effects such as atopic disease.

Promotes preferential growth of Bifidus

A statistical model was used by Shuhaimi et al. (2009) for the study of growth of Bifidobacterium pseudocatenulatum G4 under the influence of prebiotic. The physiological effect of inulin and fructooligosaccharides were investigated with sorbitol, arabinan and inoculum rate. Fractional factorial design was used to determine their effect on growth of selected bacterium in skimmed milk. They optimized their growth conditions and concluded that in 1 L fermentor, the yield increase and Central Composite Design was very effective in optimization of medium for growth of Bifidus. In a similar study, Ketabi and Dieleman (2011) investigated the effect of isomalto-oligosaccharides on intestinal microflora of rats and inferred that it specifically stimulated the growth of Lactobacilli.

Removal of cholesterol

Cholesterol was found to be evidently removed by Lactobacillus acidophilus ATCC 4962 in the presence of prebiotics in a study conducted by Liong and Shah (2005). The effect of six prebiotics including fructooligosaccharides was used to investigate the best combination for effective removal of cholesterol. The first-order model, the second-order polynomial regression model and quadratic models were used in their study.

Artificial sweetness

Apart from all the above stated prime health benefits fructooligosaccharides also has artificial sweetness and low caloric value. Artificial sweeteners are constantly in demand due to need of diabetics and health conscious consumers. Initially the demand was satisfied by aspartame agent or natural sweeteners like palatinose. Due to their popular use all types of oligosaccharides remained poorly exploited despite their functional properties (Mussatto et al. 2009).

Role in osteoporosis

The most recent trial of fructooligosaccharides supplemented with calcium in post menopausal women have registered beneficial effects in bone mineral density which is highly significant in osteoporosis (Slevin et al. 2014).