Impact of Cooking Conditions on Proximate Composition and Textural Properties of Chicken Breast Meat

The aim of this study was to evaluate the impact of cooking conditions on proximate composition and textural properties (cohesiveness and chewiness) of chicken breast meat. Eight packs of industrial skinless chicken breast meat were cooked by air frying (AF), baking (BK), deep fat frying (DF) and grilling (GR) at 170, 180 and 190oC for 0, 4, 8, 12 and 16 min. The chicken breast packs were frozen and sliced into dimensions, thawed, cooked and analysed by a two way analysis of variance. The results revealed that cooking methods significantly (p < 0.05) decreased moisture and protein contents from 75.14 to 58.25 % and 89.17 to 82.98 %, but increased fat content from 4.26 to 7.78 %, ash content from 1.95 to 2.39 %, carbohydrate content from 4.63 to 6.95 %, cohesiveness content from 0.40 to 0.52 and chewiness value from 3.63 to 6.05 kg. An increases in cooking temperatures and times decreased moisture content from 60.58 to 56.34 % and 75.14 to 47.40 % and protein content from 83.77 to 82.11 % and 89.17 to 79.45 %. Similarly, increases in cooking temperatures and times significantly (p < 0.05) increased fat content from 7.00 to 8.44 % and 4.26 to 10.12 %, ash content from 2.15 % to 2.59 % and 1.95 to 2.67 %. This study showed that increases in cooking temperatures decreased non-significantly (p > 0.05) carbohydrate content from 7.02 to 6.92 %, but increases in cooking times increased carbohydrate content from 4.63 to 7.76 %. An increases in cooking temperatures and times increased cohesiveness content from 0.50 to 0.54 and 0.40 to 0.63, chewiness value from 5.50 to 6.77 kg and 3.63 to 8.54 kg, respectively. There were no significant differences (p > 0.05) in chewiness values of samples cooked by AF and GR methods. The best cooking method/ temperature / time for low nutrient losses was BK, 170oC and 4 min

Changes in the Physiological Activities of Four Sweet Potato Varieties by Cooking Condition

The present study was performed to investigate antioxidant, anticancer, and antimicrobial activities of four Korean sweet potato variaties and to identify the changes in these biological activities under different cooking conditions. Total polyphenol content was 3.8-73.6 mg/g in 80% ethanol extracts of sweet potatoes. The polyphenol content was highest Sinjami variety (p < 0.05). Radical scavenging activity against DPPH and ABTS(.+) was high in Sinjami (p < 0.05) and the ethanol extract from Sinjami also showed effective superoxide dismutase (SOD)-like activity, which decreased significantly by steaming and roasting (p < 0.05). Ethanol extracts from the four sweet potato variaties did not inhibit cancer cell growth in MCF-7 or HepG2 cells at concentrations of 1, 10, and 100 microg/mL. Of the investigated sweet potato variaties, only Sinjami exhibited strong antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium. The antimicrobial activity of Sinjami against E. coli, St. aureus, and S. typhimurium decreased following steaming and roasting (p < 0.05). These results indicate that the Sinjami Korean sweet potato had higher polyphenol content, radical scavenging activity, SOD-like activity, and antimicrobial activity than those of the other variaties and consuming raw Sinjami might be beneficial for maintenance of biological activities.