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Functional components from Stevia rebaudiana Bert. leaves
S326
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576
Considering that nowadays consumer are looking for good foods also able to protect and/or improve their health, aim of this research work is to study the potential application of wheat bran hydrolysates, obtained through enzymatic bio-catalysis processes, as an ingredient for a fortified bread preparation. A wheat bran hydrolisate was obtained using commercial enzyme preparations selected in order to get all the enzymatic activities needed (Cellulases, Hemicellulases, Arylesterases, etc.) to get a liquid suspension containing 168,39 mg/L of ferulic acid and 703 ORAC/L as measure of the antioxidant activity. Fortified breads were prepared by substituting different percentages of water (33,3%, 50% e 100% w/w) with the hydrolised wheat bran during dough preparation. After bread making samples were extracted to recover the phenolic fraction in which the amount of ferulic acid was found proportional to the added quantity of wheat bran hydrolysate. Surprisingly the antioxidant activity measured on the same extracts shown higher values than expected considering the antioxidant activities of each individual ingredient, up to 400% than the theoretical values. The ORAC/L values vs. wheat bran hydrolysate added had an exponential trend likely due to an interaction between some component of hydrolysed bran and the yeast during the bread making process. The use of hydrolysed wheat bran could allow to prepare a “wholemeal bread” with the same beneficial effects provided by wheat bran but with a more acceptable palatability and having enhanced antioxidant properties. These features could have a possible relevant impact on application in fortified foods sectors. doi:10.1016/j.jbiotec.2010.09.324 [P-F.81] Functional components from Stevia rebaudiana Bert. leaves S. Tavarini ∗ , M. Ribuoli, M. Bimbatti, L.G. Angelini University of Pisa, Italy Keywords: Stevia rebaudiana; functional component; steviol glycosides; antioxidant activity In the last years there is an increasing interest for foods characterized by a low caloric contribution and a high antioxidant and phytochemical power. For this reason, much attention has been focused on dietary natural antioxidants, capable to inhibit reactive oxygen species, which are involved in determining several human pathologies, such as cancer, arteriosclerosis, diabetes, cardio-vascular diseases and degenerative illness connected to the aging process. In this contest, Stevia rebaudiana Bert., a component of Asteraceae family, plays an important role for the development of new ingredients, characterized by low calories and high antioxidant activity. Stevia leaves contain steviol glycosides which are responsible for the typical sweet taste. In addition to its interesting sweetening property, the Stevia extract shows many pharmacological properties. Within a R&D project founded by Eridania Sadam Company, a series of field and laboratory trials have been carried out in order to assess the effect of genotype, cultural practices (nitrogen fertilization, harvest time and crop age) and propagation methods (micropropagation, stem cutting and seed propagation) on leaf production, steviol glycoside content, total phenols and antioxidant properties. The obtained results showed a significant effect of genotype on leaf production and glycosides content as well as on the antioxidant properties. In the same, the propagation method and cultural practices strongly influenced the stevioside and rebaudioside A content and the total antioxidant capacity. Significant relationships have been found between rebaudioside A
and total phenols with total antioxidant capacity. The main results achieved will be presented and discussed. doi:10.1016/j.jbiotec.2010.09.325 [P-F.82] A study of different multi effect evaporators designed for thermal processing of tomato paste: optimization and quality evaluation R. Simpson 1,2,∗ , A. Urtubia 1,2 , A. Abakarov 1 , S. Almonacid 1,2 1
Universidad Técnica Federico Santa María, Chile Centro Regional de Estudios para Alimentos Saludables, Chile Keywords: Multi Effect Evaporators; Lycopene; Product quality 2
Introduction: The main purpose of this research is the development of a model for optimizing multiple–effect evaporator systems for tomato paste concentration, in which the diluted food enters at 5◦ Brix and must be processed to 30◦ Brix. Methodology: The economic evaluation included a quality parameter that influences final price, modifying the classical chemical engineering view that considers only cost minimization for the best system design. In this particular case, the sale price will be considered directly dependent upon the final lycopene retention. In addition, the final content of ascorbic acid and furosine as well as the color will be analyzed as part of quality determination. Results and Discussion: A 4-effect evaporator system returns the best gains in the basic disposition. Variations in the arrangement and in the operating conditions were also evaluated, and analyzed as follows: a) the introduction of a pre-heating and preconcentrating stage; b) the use of a larger evaporator; c) the utilization of stages with different areas; and d) changes of steam pressure necessary for the operation. The best configuration for economic analysis and lycopene retention was identified as the one without recycling, with an equal heat exchange area for each evaporator and with the highest fresh, hot steam pressure, offering a Net Present Worth (NPW) of US$ 45.6 million. Conclusions: The steady state values of the evaporator system were able to be linked to the reaction kinetics of the target attribute, lycopene. A mathematical model was successfully developed, and then an economic evaluation of the optimum design and operating conditions of the evaporation system. With the inclusion of lycopene as a quality parameter, the optimum number of effects decreases from 4 to 3 when compared with total cost analysis. doi:10.1016/j.jbiotec.2010.09.326 [P-F.83] The Functional Properties of Casein Glycomacropeptide as Stabilising Agent for Emulsion Based Food Products R. Kovacova ∗ , M. Sedlarik, M. Mihulova, M. Sirmerova, L. Curda, J. Stetina The Institute of Chemical Technology, Prague, Czech Republic Keywords: casein glycomacropeptide; functional properties; emulsion The casein glycomacropeptide (CMP) has received much attention in recent years for its beneficial physiological and biological properties (inhibition of bacterial and viral adhesion, ability to bind some enterotoxins, promotion of bifidobacterial growth, suppression of gastric secretion, etc.) as well as for its interesting functional properties (emulsifying, gelling, water binding). In this
Special Abstracts / Journal of Biotechnology 150S (2010) S1–S576
Considering that nowadays consumer are looking for good foods also able to protect and/or improve their health, aim of this research work is to study the potential application of wheat bran hydrolysates, obtained through enzymatic bio-catalysis processes, as an ingredient for a fortified bread preparation. A wheat bran hydrolisate was obtained using commercial enzyme preparations selected in order to get all the enzymatic activities needed (Cellulases, Hemicellulases, Arylesterases, etc.) to get a liquid suspension containing 168,39 mg/L of ferulic acid and 703 ORAC/L as measure of the antioxidant activity. Fortified breads were prepared by substituting different percentages of water (33,3%, 50% e 100% w/w) with the hydrolised wheat bran during dough preparation. After bread making samples were extracted to recover the phenolic fraction in which the amount of ferulic acid was found proportional to the added quantity of wheat bran hydrolysate. Surprisingly the antioxidant activity measured on the same extracts shown higher values than expected considering the antioxidant activities of each individual ingredient, up to 400% than the theoretical values. The ORAC/L values vs. wheat bran hydrolysate added had an exponential trend likely due to an interaction between some component of hydrolysed bran and the yeast during the bread making process. The use of hydrolysed wheat bran could allow to prepare a “wholemeal bread” with the same beneficial effects provided by wheat bran but with a more acceptable palatability and having enhanced antioxidant properties. These features could have a possible relevant impact on application in fortified foods sectors. doi:10.1016/j.jbiotec.2010.09.324 [P-F.81] Functional components from Stevia rebaudiana Bert. leaves S. Tavarini ∗ , M. Ribuoli, M. Bimbatti, L.G. Angelini University of Pisa, Italy Keywords: Stevia rebaudiana; functional component; steviol glycosides; antioxidant activity In the last years there is an increasing interest for foods characterized by a low caloric contribution and a high antioxidant and phytochemical power. For this reason, much attention has been focused on dietary natural antioxidants, capable to inhibit reactive oxygen species, which are involved in determining several human pathologies, such as cancer, arteriosclerosis, diabetes, cardio-vascular diseases and degenerative illness connected to the aging process. In this contest, Stevia rebaudiana Bert., a component of Asteraceae family, plays an important role for the development of new ingredients, characterized by low calories and high antioxidant activity. Stevia leaves contain steviol glycosides which are responsible for the typical sweet taste. In addition to its interesting sweetening property, the Stevia extract shows many pharmacological properties. Within a R&D project founded by Eridania Sadam Company, a series of field and laboratory trials have been carried out in order to assess the effect of genotype, cultural practices (nitrogen fertilization, harvest time and crop age) and propagation methods (micropropagation, stem cutting and seed propagation) on leaf production, steviol glycoside content, total phenols and antioxidant properties. The obtained results showed a significant effect of genotype on leaf production and glycosides content as well as on the antioxidant properties. In the same, the propagation method and cultural practices strongly influenced the stevioside and rebaudioside A content and the total antioxidant capacity. Significant relationships have been found between rebaudioside A
and total phenols with total antioxidant capacity. The main results achieved will be presented and discussed. doi:10.1016/j.jbiotec.2010.09.325 [P-F.82] A study of different multi effect evaporators designed for thermal processing of tomato paste: optimization and quality evaluation R. Simpson 1,2,∗ , A. Urtubia 1,2 , A. Abakarov 1 , S. Almonacid 1,2 1
Universidad Técnica Federico Santa María, Chile Centro Regional de Estudios para Alimentos Saludables, Chile Keywords: Multi Effect Evaporators; Lycopene; Product quality 2
Introduction: The main purpose of this research is the development of a model for optimizing multiple–effect evaporator systems for tomato paste concentration, in which the diluted food enters at 5◦ Brix and must be processed to 30◦ Brix. Methodology: The economic evaluation included a quality parameter that influences final price, modifying the classical chemical engineering view that considers only cost minimization for the best system design. In this particular case, the sale price will be considered directly dependent upon the final lycopene retention. In addition, the final content of ascorbic acid and furosine as well as the color will be analyzed as part of quality determination. Results and Discussion: A 4-effect evaporator system returns the best gains in the basic disposition. Variations in the arrangement and in the operating conditions were also evaluated, and analyzed as follows: a) the introduction of a pre-heating and preconcentrating stage; b) the use of a larger evaporator; c) the utilization of stages with different areas; and d) changes of steam pressure necessary for the operation. The best configuration for economic analysis and lycopene retention was identified as the one without recycling, with an equal heat exchange area for each evaporator and with the highest fresh, hot steam pressure, offering a Net Present Worth (NPW) of US$ 45.6 million. Conclusions: The steady state values of the evaporator system were able to be linked to the reaction kinetics of the target attribute, lycopene. A mathematical model was successfully developed, and then an economic evaluation of the optimum design and operating conditions of the evaporation system. With the inclusion of lycopene as a quality parameter, the optimum number of effects decreases from 4 to 3 when compared with total cost analysis. doi:10.1016/j.jbiotec.2010.09.326 [P-F.83] The Functional Properties of Casein Glycomacropeptide as Stabilising Agent for Emulsion Based Food Products R. Kovacova ∗ , M. Sedlarik, M. Mihulova, M. Sirmerova, L. Curda, J. Stetina The Institute of Chemical Technology, Prague, Czech Republic Keywords: casein glycomacropeptide; functional properties; emulsion The casein glycomacropeptide (CMP) has received much attention in recent years for its beneficial physiological and biological properties (inhibition of bacterial and viral adhesion, ability to bind some enterotoxins, promotion of bifidobacterial growth, suppression of gastric secretion, etc.) as well as for its interesting functional properties (emulsifying, gelling, water binding). In this