Spray‐Dried Structured Lipid Containing Long‐Chain Polyunsaturated Fatty Acids for Use in Infant Formulas

Human milk fat (HMF) analogs are structured lipids (SLs) modified to have palmitic acid content at the sn‐2 position of the triacylglycerol (TAG) and fatty acid composition comparable to HMF. Some of these SLs are also designed to incorporate long‐chain polyunsaturated fatty acids (LCPUFAs) because of their important role in infant development. In this study, Maillard reaction products (MRPs), obtained from heated whey protein isolates and corn syrup solids (CSS) solution, were used as encapsulants for microencapsulation of 2 enzymatically synthesized SLs for infant formula applications. The encapsulated SL powders were obtained through spray‐drying and evaluated in terms of their microencapsulation efficiency, chemical and physical properties, oxidative stability, and dispersibility. The microencapsulation efficiency of the SLs was 90%. Dispersibility test using particle size measurement demonstrated that these powders dispersed quickly into a homogeneous suspension. The encapsulated SL powders had low peroxide and thiobarbituric acid‐reactive substances values. Lower oxidative stability was obtained in the powder containing SL with a higher degree of unsaturation and a lower concentration of tocopherols. The results demonstrated that the degree of fatty acid unsaturation and concentration of endogenous antioxidant in starting oils influenced the oxidative stability of the encapsulated SLs.     

Production and Characterization of DHA and GLA-Enriched Structured Lipid from Palm Olein for Infant Formula Use

Palm olein was modified via lipase-catalyzed acidolysis reaction to obtain fatty acid composition and positional distribution similar to human milk fat. In the reaction, a free fatty acid mix containing 23.23 % docosahexaenoic (DHA), 31.42 % gamma-linolenic (GLA), and 15.12 % palmitic acid was employed. The DHA and GLA were incorporated into the structured lipid (SL) product to improve its nutritional value. Response surface methodology (RSM) was used to investigate the effects of reaction time and substrate mole ratio (palm olein to a free fatty acid mix) on the amount of palmitic acid at the sn-2 position of SL triacyglycerols (TAG), and on the total DHA and GLA incorporation. Gram-scale production of SL was performed using the conditions predicted by RSM to maximize the content of palmitic acid at the sn-2 position. Verification of the predictions from RSM confirmed its practical utility. The resulting SL had 35.11 % palmitic acid at the sn-2 position, with 3.75 % DHA and 5.03 % GLA. Differential scanning calorimetry and HPLC analyses of the TAG revealed changes in their polymorphic profiles and TAG molecular species of SL compared to palm olein. The SL from this study can potentially be used in infant formula formulations.     

Enrichment of palm olein with long chain polyunsaturated fatty acids by enzymatic acidolysis

Long-chain polyunsaturated fatty acids (LCPUFA) such as docosahexaenoic (DHA) and arachidonic (ARA) acids have great benefits for the development and maintenance of human brain functions. The production of structured lipid (SL) by acidolysis of palm olein with a free fatty acid mixture obtained from DHASCO^® and ARASCO^®, catalyzed by Novozym 435^® in hexane was optimized by response surface methodology (RSM). Three independent factors chosen were substrate mole ratio of total free fatty acids to palm olein (6–18 mol/mol), reaction temperature (55–65 °C), and reaction time (12–24 h). Good quadratic models were obtained for the incorporation of DHA + ARA (response 1) and their incorporation at the sn-2 position (response 2) by multiple regression and backward elimination. The models were verified by carrying out acidolysis reaction at several random combinations of the independent factors. The optimal condition generated from the models resulted in 25.25 g/100 g total incorporation of DHA + ARA and 17.20 g/100 g DHA + ARA incorporation at the sn-2 position. The fatty acid composition of SL was comparable to that of human milk fat. The SL produced in this study has potential for use in infant formulas as well as in nutraceutical applications for pregnant women.     

Gynaecological conditions associated with HIV infection in women who are partners of HIV-positive Thai blood donors

Women who were partners of HIV-positive blood donors were enrolled in a study of heterosexual HIV transmission between March 1992 and December 1996 and were interviewed and examined. Gynaecological conditions, including cervical dysplasia, human papillomavirus (HPV) infection, gonorrhoea, chlamydial infection, trichomoniasis, bacterial vaginosis, vaginal candidiasis and syphilis were assessed in addition to HIV status and CD4 level. Of 481 women enrolled, 224 (46.6%) were HIV seropositive. HIV-infected women were more likely to have abnormal vaginal discharge on physical examination (OR=2.6, P <0.01), HPV infection with a high-risk type (OR=6.9, P <0.01), and cervical dysplasia (OR=5.3, P <0.01). The prevalence of other gynaecological conditions detected at the enrolment visit did not differ by HIV status. History of prior STD (OR=2.0, P <0.01) was more common among HIV-infected women. The median CD4 count was 400 cells/microl among HIV-infected women. The prevalence of abnormal vaginal discharge and bacterial vaginosis increased significantly with decreasing CD4 count. The prevalence of ectopy, vaginal candidiasis, and cervical dysplasia increased with decreasing CD4 count, but these trends were not significant. We conclude that HIV-infected Thai women appear to have increased prevalences of abnormal vaginal discharge, squamous intraepithelial lesions and self-reported history of STD.