Yoon Hyuk Chang

Physicochemical, microbial, and sensory properties of yogurt supplemented with nanopowdered chitosan during storage.

This study was carried out to determine the possibility of adding nanopowdered chitosan (NPC) into cholesterol-reduced yogurt to improve the functionality of yogurt and the effects of adding NPC on the physicochemical, microbial, and sensory properties of the products during storage. The pH values and mean lactic acid bacteria counts of NPC-added (0.3 to approximately 0.7%, wt/vol) and cholesterol-reduced yogurt ranged from 4.19 to 4.41 and from 4.75 x 10(8) to 9.70 x 10(8) cfu/mL, respectively, when stored at 4 degrees C for 20 d, thereby indicating a possibility of prolonging the shelf life of yogurt. In color, the a* and b* values for cholesterol-reduced yogurt were not significantly influenced by the addition of NPC (0.1 to approximately 0.7%, wt/vol); however, the L* values significantly decreased with the addition of the greatest concentration (0.7%, wt/vol) of NPC at 0-d storage. The sensory test revealed that the astringency scores significantly increased at 0-d storage when the greatest concentration (0.7%, wt/vol) of NPC was added into cholesterol-reduced yogurt. Based on the data obtained from the current study, it is concluded that concentrations (0.3 to ~0.5%, vol/vol) of NPC could be used to produce an NPC-added and cholesterol-reduced yogurt without significantly adverse effects on the physicochemical, microbial, and sensory properties.

The Preventive Effects of Nanopowdered Peanut Sprout-added Caciocavallo Cheese on Collagen-induced Arthritic Mice.

The present study was carried out to investigate the effects of nanopowdered peanut sprout-added Caciocavallo cheese (NPCC) on the prevention and treatment of rheumatoid arthritis in DBA/IJ mice immunized with type II collagen. After the induction of arthritis, the mice were being divided into five groups: (1) normal, no immunization; (2) CIA, collagen-induced arthritis; (3) MTX, collagen-induced arthritis treated with methotrexate (0.3 mg/kg body weight); (4) CC, collagen-induced arthritis treated with Caciocavallo cheese (0.6 g/d); (5) NPCC, collagen-induced arthritis treated with nanopowdered peanut sprout-added Caciocavallo cheese (0.6 g/d). Nanopowdered peanut sprout was ranged from 300 to 350 nm, while regular powdered peanut sprouts were ranged from 50 to 150 μm. The NPCC group had considerable reductions of clinical scores and paw thicknesses at the end of experiment as compared to the CIA group. In the serum analysis, the TNF-α, IL-1β, IL- 6 and IgG1 levels in the NPCC group have decreased by 69.4, 75.9, 66.6, and 61.9%, respectively, when compared to the CIA group. The histological score and spleen index of the NPCC group were significantly lower than the CIA group. In conclusion, the feeding NPCC method could delay and/or prevent the rheumatoid arthritis in the collagen-induced arthritis mouse model. Based on this study, nanopowdered peanut sprouts could be applied to various functional cheeses.

Physicochemical and Sensory Properties of Appenzeller Cheese Supplemented with Powdered Microcapsule of Tomato Extract during Ripening.

The objective of this study was to determine the physicochemical and sensory properties of Appenzeller cheese supplemented with different concentrations (0, 1, 2, 3, and 4%, w/w) of powdered microcapsules of tomato extracts (PMT) during ripening at 14℃ for 6 mon. The particle sizes of PMT ranged from 1 to 10 m diameter with an average particle size of approximately 2 m. Butyric acid (C4) concentrations of PMT-added Appenzeller cheese were significantly higher than that of the control. Lactic acid bacteria counts in the cheese were not significantly influenced by ripening time from 0 to 6 mon or the concentrations (0-4%, w/w) of PMT. In terms of texture, the hardness of PMT-added Appenzeller cheese was significantly increased compared to the control. The gumminess and chewiness of PMT-added Appenzeller cheese were similar to those of the control. However, both cohesiveness and springiness of PMT-added Appenzeller cheese were slightly decreased. In sensory analysis, bitterness and sourness of Appenzeller cheese were not significantly changed after supplementation of PMT, but sweetness of the cheese was significantly increased after increasing the ripening time from 0 to 6 mon and increasing the concentration from 1 to 4% (w/w). Based on these results, the addition of the concentrations (1-4%, w/w) of PMT to Appenzeller cheese can be used to develop functional Appenzeller cheese.

Structural Characterization of Cellulose Obtained from Extraction Wastes of Graviola (Annona muricata) Leaf

Cellulose is one of the most common functional ingredients in food products and has been widely used as fat replacers and stabilizers. In the present study, the structural properties of cellulose obtained from extraction wastes of graviola (Annona muricata.) leaf (CWG) were characterized via scanning electron microscope (SEM), X-ray diffraction (XRD), fourier transform-infrared (FTIR), and 13C nuclear magnetic resonance (NMR) analyses. Extraction and purification of CWG were accomplished by alkali treatment and bleaching processes. An elongated, fibrous structure of CWG was observed in SEM analysis. The XRD, FTIR, and 13C NMR spectra of CWG were compared with microcrystalline cellulose (control cellulose) and it was found that CWG exhibited similar structural characteristics to the control. XRD diffractogram of CWG showed typical peaks (2θ=15° and 22.6°) of cellulose I. According to the specific peaks (898, 1,057, and 1,430 cm−1) and chemical shifts (104.5, 88.5, 72~75, and 64.6 ppm) obtained by FTIR and NMR analyses, respectively, it was cofirmed that cellulose was successfully extracted from CWG.

Physicochemical, Microbial, and Sensory Properties of Queso Blanco Cheese Supplemented with Powdered Microcapsules of Tomato Extracts

The present study examined the physical, chemical, microbial, and sensory characteristics of Queso Blanco cheese supplemented with powdered microcapsules containing tomato extracts (0.5-2.0%) during storage at 7°C for 60 d. The lactic acid bacterial count and lycopene concentrations in Queso Blanco cheese supplemented with powdered microcapsules were significantly higher than those of the control. In a texture analysis, the gumminess, chewiness, and hardness values for Queso Blanco cheese were significantly higher with increasing concentrations of the powdered microcapsules containing tomato extracts. Total short-chain fatty acids in Queso Blanco cheese supplemented with powdered microcapsules containing tomato extracts were not significantly altered compared to the control. Sensory evaluation scores for the yellowness, tomato taste, and firmness of Queso Blanco cheese were significantly higher after supplementation with powdered microcapsules containing tomato extracts.