Foaming behavior of poly(lactic acid) with different D-isomer content based on supercritical CO2-induced crystallization

Using supercritical carbon dioxide (sc-CO2) as a physical foaming agent, the effect of sc-CO2 on the formation of crystalline domains and subsequently on the foaming behaviors of the two grades of PLA with different D-isomer content were investigated in a wide foaming temperature range. The PLA’s final crystallinity is significantly increased with decreasing annealing temperature and by reducing the D-isomer content. Cellular structure results show that not only the crystallinity but also the crystalline morphology play an important role in cellular structure. A novel spherulite morphology including ringless and ring-banded morphology in the same spherulite was formed at lower foaming temperature, as a result, some entities were nonuniformly distributed in the PLA foams. Uniform and closed cellular structure were obtained when only the ring-banded spherulites were formed. An opened and interconnected cellular structure is tended to be formed because of the synergistic effect of high temperature and plasticization of CO2. Based on the crystallinity and morphology, a suitable foaming window as a function of temperature is proposed. It is found that PLA with 4.1% D-isomer content had much broader suitable foaming window range to produce homogeneous cellular structure.

Reverse Phase Chiral HPLC Method for Enantiomeric Excess Determination of 2-Aminobutanamide

A reverse phase chiral HPLC method was developed for the determination of (R)-2-aminobutanamide isomer content in (S)-2-amino-butanamide key starting material for levetiracetam drug substance by using a CROWNPAK CR (+) column. Perchloric acid solution (0.05 %) was used as mobile phase and the flow rate was finalized as 0.3 mL/min. UV detection wavelength was 200 nm and column temperature was set as 15 ºC. The limit of detection and limit of quantification were 0.0002 mg/mL and 0.0005 mg/mL, respectively. The linearity calibration curve of (R)-2-aminobutanamide was shown good from the range of 0.0005 mg/mL to 0.004 mg/mL. The recovery of (R)-2-aminobutanamide isomer was between the range of 93 to 106 % in presence of (S)-2-aminobutanamide. The method was validated and found to be precise, accurate and robust. The method can be used for determination of (R)-2-aminobutanamide in presence of (S)-2-aminobutanamide, which is the key intermediate for preparation of levetiracetam. This method was validated in as per ICH Q2 (R1) and USP validation of compendial methods (1225).

Evaluation of the quality of local butters: A new approach based on Raman spectroscopy and supported by the classical pycnometer method

In this study, the quality of the local Romanian butters was investigated using the classical pycnometer and optic microscopy methods, combined with Raman spectroscopy. We used a pool of 10 samples with different characteristics, and analyzed them by the three aforementioned methods. Pycnometric measurements showed a direct correlation between the fat content and the density values of the samples. Raman spectroscopy validated the results from the pycnometric measurements and the optical microscopy and indicated several other properties, such as protein content, hydration, saturation level of the polycarbonate chains, as well as the total cis isomer content and the type of arrangement preferred by the aliphatic chains (polymorphic transition). The methods employed in the present study have a strong potential to become analytical tools for the food industry and food safety agencies in order to assess the quality of butters and margarines, in a fast and cost-effective manner.

trans Fatty Acids in Polish Pastry

ABSTRACT Because potentially harmful trans fatty acids (TFAs) should be eliminated from the diet, each country should have updated estimates of TFA content in food. The purpose of the study was to provide data on TFA content in pastry products commercialized in the Polish market. Products made using hydrogenated fats (as declared by manufacturers) were tested. Samples were acquired between April 2017 and July 2017. Extraction of fat from all pastries was carried out by the method of Folch et al. The fatty acid (FA) composition, especially TFA content in extracted fats, was determined by gas chromatography. Fat in the products was characterized by a high level of saturated fatty acid (SFA; ca. 42 g/100 g of FA), with the exception of one sample. A great diversity of total TFA content in fat of the products was found (0.1 to 13.5 g/100 g of FA). Of the products tested, 37.5% had TFAs in excess of 2%. Furthermore, partially hydrogenated fats were the source of TFAs in the analyzed products, as demonstrated by high content of elaidic acid. In addition, there was a trend of a decrease in the daily intake of TFAs of industrial origin with pastry products (0.14 g) compared with earlier studies. These results highlight the ongoing need for improvement in terms of trans isomer content in pastry products in Poland. This study confirms the importance of developing effective policies for reducing the TFA content of food. HIGHLIGHTS