Valeria Messina
UNIDEF-MINDEF-CITEDEF-CONICET, Argentina
Title: Quality of freeze dried peach snacks: Scanning electron microscopy combined with image analysis techniques
Biography
Valeria Messina received her Degree in pharmacy. She is a researcher at the Solid Research Center-Scientific and Technological Research Institute for Defense, UNIDEF (Strategic I & D or Defense)-CONICET-Ministry of Defense, Buenos Aires, Argentina. She is a Member of the National Council for Scientific and Technical Research.
Abstract
The causes of food waste or loss are numerous and occur at the stages of production, processing, retailing and consumption. Peaches must be processed quickly to maintain their quality because they are seasonal and their shelf life is short. An option to process and to maintain quality is to apply freeze drying methods. The aim of the present research was to evaluate quality parameters of freeze dried peach to increase peach shelf-life, consumption and to decrease waste of fruit. Peaches were ripped on maturity time and stored for 16 days, freeze dried and analyzed every 4th day (T1 (4 days), T2 (8 days), T3 (12 days), T4 (16 days) to establish quality among storage and process for peach snacks. Microstructure was carried out applying a Scanning Electron Microscopy. Texture and color parameters were analyzed by Image analysis techniques and physicochemical parameters by conventional analysis. Statistical differences (P<0.05) were obtained for color, texture, water activity and porosity. Results revealed that after 12 days of storage/freeze drying peach snacks showed lower pore size with higher amounts of pore, which affected rehydration process leading to a harder sample. Color also was affected, decreases in lightness and increases in redness appeared. Optimal quality in peach snacks can be obtained at storage/freeze drying between 8-12 days. This research incorporates a quick approach to quality applying image analysis techniques and it will benefit to increase shelf-life and consumption of fat-free snack peaches and to decrease the effect of wasting fruit.
Yi Xuan Li
Korea University, Republic of Korea
Title: Enhanced aqueous dispersibility of alpha-lipoic acid through complex formation with octenylsuccinylated high amylose starch
Biography
Yi Xuan Li undertakes research on utilization of nano-encapsulation of bioactive compounds into starch matrices to enhance the dispersibility, stability and bioavailability of labile ingredients. She explored a facile preparation process to disperse labile compounds in aqueous media by using starch matrices encapsulation. She evaluated the stability, in vitro digestibility and in vivo bioavailability of nano-encapsulation systems for targeted delivery of labile ingredients. After years of experience in research, she has the expertise in systematic development of efficiently targeted delivery of bioactives through nano-encapsulation into starch matrices.
Abstract
Alpha-lipoic acid (ALA) which engages in mitochondrial energy metabolism as an essential co-factor is well known to possess a potent antioxidant activity. However, problems such as poor water solubility, high sensitivity to light and heat, and limited bioavailability make ALA difficult in potential application. Encapsulation of ALA with starch could be expected to mitigate the disadvantageous properties of ALA. A high amylose maize starch (70% amylose) substituted by octenyl succinic anhydride was used to complex with ALA for the enhanced dispersion properly in aqueous media. An aliquot of ALA-ethanol solution (10%w/v) was dispersed in gelatinized starch solution (1.0% w/v) at 70°C for 3h, and then cooled for 12h under continuous stirring followed by an ultrasonication. OS was more favored in enhancing the dispersibility of ALA (84.20% recovery) than native high amylose starch (70.79% recovery), whereas beta-cyclodextrin dispersion of ALA exhibited extremely fluctuated ALA recovery. The optimally prepared OS-ALA dispersion was milky white and contained particles with a narrow size distribution (200-300 nm). The dispersion contained crystalline V-complexes of ALA and some OSA-modified high amylose starch was effectively retarding the aggregation of ALA in the dispersion. Therefore, OS behaved as a favorable stabilizer for dispersing ALA in aqueous by forming V-amylose complex, which could be used as an efficient method to protect bioactive compounds.