Panuwat Suppakul

Antioxidant activities of curcumin and ascorbyl dipalmitate nanoparticles and their activities after incorporation into cellulose-based packaging films.

Curcumin (Ccm) and ascorbyl dipalmitate (ADP) nanoparticles (NPs) with average sizes of ∼50 and ∼80 nm, respectively, were successfully produced by rapid expansion of subcritical solutions into liquid solvents (RESOLV). Pluronic F127 was employed as a stabilizer for both Ccm- and ADP-NPs in an aqueous receiving solution. Antioxidant activities of the Ccm-NPs and ADP-NPs were subsequently investigated using four assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ABTS radical cation decolorization, β-carotene bleaching, and ferric reducing antioxidant power. Ccm-NPs and ADP-NPs showed higher antioxidant activities than those of Ccm and ADP. Ccm-NPs yielded higher antioxidant activities than those of Ccm in ethanol and water (Ccm-EtOH and Ccm-H(2)O), respectively. ADP-NPs yielded lower antioxidant activities than that of ADP in ethanol (ADP-EtOH) but higher activities than that of ADP in water (ADP-H(2)O). Moreover, incorporation of Ccm-NPs and ADP-NPs into cellulose-based films indicated that Ccm-NPs and ADP-NPs significantly enhanced the antioxidant activities of Ccm and ADP (p < 0.05). Our results show that the environmentally benign supercritical CO(2) technique should be generally applicable to NP fabrication of other important bioactive ingredients, especially in liquid form. In addition, we suggest that Ccm-NPs and ADP-NPs can be used to reduce the dosage of Ccm and ADP and improve their bioavailability, and thus merit further investigation for antioxidant packaging film and coating applications.

Active and intelligent packaging: The indication of quality and safety

ABSTRACT The food industry has been under growing pressure to feed an exponentially increasing world population and challenged to meet rigorous food safety law and regulation. The plethora of media consumption has provoked consumer demand for safe, sustainable, organic, and wholesome products with “clean” labels. The application of active and intelligent packaging has been commercially adopted by food and pharmaceutical industries as a solution for the future for extending shelf life and simplifying production processes; facilitating complex distribution logistics; reducing, if not eliminating the need for preservatives in food formulations; enabling restricted food packaging applications; providing convenience, improving quality, variety and marketing features; as well as providing essential information to ensure consumer safety. This chapter reviews innovations of active and intelligent packaging which advance packaging technology through both scavenging and releasing systems for shelf life extension, and through diagnostic and identification systems for communicating quality, tracking and brand protection.

Preparation of Polydiacetylene Vesicle and Amphiphilic Polymer as Time-Temperature Indicator

Polydiacetylene (PDA) was used as a colorimetric indicator depended on temperature and time. This paper presents a new time-temperature indicator based on PDA vesicle and amphiphilic polymer. The 10,12-pentacosadiynoic acid (PCDA) was prepared with different concentration of Pluronic F127 which was varied from 0 to 4 % w/v, respectively. After that, there was obtained in different temperature (30-50°C) until clearly color change. This solution could gradually change from blue to red color which it could observe by UV-Vis spectrophotometer. The absorbance in each solution was reported at 640 and 540 nm, respectively, and then calculated by the color response (CR). In addition, the CR increased that directly related with temperature and time, when the concentration of F127 was constant. Also, the CR increased that directly related with temperature and concentration of F127, when time was constant. This method could have potential application as a new time-temperature indicator.

Fabrication of Novel Bioactive Cellulose-Based Films Derived from Caffeic Acid Phenethyl Ester-Loaded Nanoparticles via a Rapid Expansion Process: RESOLV

Caffeic acid phenethyl ester (CAPE) nanoparticles (NPs) with an average size of ∼40 nm obtained from TEM and binomial average sizes of ∼90 and ∼400 nm obtained from DLS were successfully produced by rapid expansion of subcritical solutions into liquid solvents (RESOLV). The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of CAPE and CAPE-NPs were determined by plate count method against 12 pathogenic and spoilage bacteria and 3 strains of yeast. Total phenolic content (TPC) and antioxidant activities of CAPE-NPs were quantified and subsequently investigated using two assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric reducing antioxidant power (FRAP). CAPE-NP-incorporated cellulose-based films were prepared and characterized. MICs and MBCs of CAPE-NPs against most bacteria and Candida albicans were 700 and 1400 μg/mL, respectively. CAPE-NPs yielded a TPC value of 426.74 μgGAE/mg and lower antioxidant activities than those of CAPE in ethanol (CAPE-EtOH), whereas BHT yielded lower FRAP than that of CAPE-NPs. The impregnation of CAPE into cellulose-based films was confirmed by FTIR spectra. Moreover, incorporation of only 0.5 wt % CAPE-NPs into the films resulted in an inhibitory effect against microorganisms. Fortunately, incorporation of higher concentration of CAPE-NPs-MC films led to a significantly higher antioxidant activity and vice versa. This indicated that CAPE-NPs significantly enhanced the antimicrobial and antioxidant activities of CAPE. The results show that the environmentally benign supercritical CO2 technique should be generally applicable to NP fabrication of other important bioactive ingredients, especially in liquid form. In addition, it is suggested that CAPE-NPs can be used to reduce the dosage of CAPE and improve their bioavailability and thus merit further investigation for bioactive packaging film and coating applications.

Effect of air temperature and velocity on moisture diffusivity in relation to physical and sensory quality of dried pumpkin seeds

ABSTRACT Understanding the effect of drying process parameters on food quality is helpful in process optimization and control. The objective of this work is to understand the effect of mild and harsh effective moisture diffusivity (Deff), varied by air temperature and velocity, of drying processes on the physical and sensory quality of flat food products. Pumpkin seeds were selected as a food representative. It was found that increments of air temperature and velocity resulted in increased Deff and brown color on seed hull surfaces and embryos, but decreased hardness of seed embryos. Changes in taste and aroma of seed embryos were able to be sensed. Indicating that Deff is related to seed physical quality. Similar phenomena occurred with both tray and fluidized bed drying. Air temperature, velocity, and Deff should be controlled to ensure the best dried flat food products. Mild drying conditions are potentially preferred for good physical and sensory quality.