Biosurfactants in the Food Industry - Biosurfactants: Research Trends and Applications - page 190

Huge amounts of water are used during the process producing effluents con-
taining dissolved sugars and proteins, fats, and possibly residues of additives.
Besides, these effluents are characterized by their high BOD value, and their incor-
rect disposal represents an environmental problem.
Cheese whey was used as a substrate to BS production in a two-step batch cultiva-
tion process by C. bombicola and Cryptococcus curvatus . In the first step, C. curvatus
was grown on deproteinized whey concentrates; the cultivation broth was disrupted
with a glass bead mill, and it served a medium for growth and sophorolipid produc-
tion by C. bombicola (Daniel et al., 1999). Also, whey showed as a potential sub-
strate to BS production by L. pentosus (Rodrigues et al., 2006b). Yarrowia lipolytica ,
Micrococcus luteus , and Burkholderia cepacia showed capability to produce BS
from whey wastewater. The BSs produced were biochemically characterized and the
properties were analyzed. The BS showed good emulsification index and hemolytic
and surface activities (Yilmaz et al., 2009).
Bs P roDuCtion from u nConventional s uBstrates
Combinations of distillery waste with other industrial wastes such as whey waste, fruit
processing waste, and sugar industry effluent were evaluated for BS production by
four bacterial isolates from a distillery unit. The combinations of wastes improved the
yields of BSs and reduced the chemical oxygen demand of the combined wastes. Total
sugars, nitrogen, and phosphate levels reduced in the range of 79%-86%, 58%-71%,
and 45%-59%, respectively, showing the environmental and economical benefits
derived from the use of wastes as substrates to BS production (Dubey et al., 2012).
Another attractive substrate to BS production is cashew apple juice. This substrate
is rich in reducing sugar, vitamins, and mineral salts and is cheap (US $ 1.00/kg), which
make an interesting and inexpensive culture medium. Acinetobacter calcoaceticus ,
B. subtilis , and P. aeruginosa showed potential to growth at cashew apple juice and
produce BS (Rocha et al., 2006, 2007, 2009).
Some reviews about the use of unconventional substrates and agroindustrial resi-
dues to BS production have been published (Makkar and Cameotra, 1999; Makkar
and Cameotra, 2002; Nitschke and Costa, 2007; Makkar et al., 2011; Henkel et al.,
2012) showing that production cost of BS still remains the limiting factor to indus-
trial process scale, and many research have been done based on the utilization of
waste conversion to bioproducts.
CONCLUSION
Increasing demand for natural ingredients and green chemistry stimulates the exploita-
tion of BSs. These molecules show singular properties very useful in food processing
even as an ingredient, a cleaning agent, or a prospective high-value product obtained
from food waste substrates. The main challenges to be overcome to improve BS utili-
zation by food industry are the generation of more data about their toxicity including
in vivo tests; additionally, more research has to be done applying BS in food matrix
in order to evaluate not only their properties but also their interaction with food com-
ponents. Furthermore, there is a lack of information about BS contribution on sensory