Effect of Different Cooking Methods on the Concentration of Vitamin C in Cowpea Vegetable (Vigna unguiculata)

Background: Vitamin C is a water-soluble vitamin widely distributed in nature, mostly rich in fresh fruits and green leafy vegetables. The amount of Vitamin C in a given food depends on soil condition, climate in their area of growth, storage condition after harvest, and methods of preparation. Much amount of Vitamin C in vegetables is lost during cooking and there are still limited information on the impact of different cooking methods on the vitamin C content in leafy vegetable like cowpea vegetable (Vigna unguiculata). It is upon this background that this study aimed to determine the concentration of Vitamin C in cowpea vegetable when cooked using different cooking methods. Methodology: Vitamin C concentration in a solution of cowpea vegetable cooked by different cooking methods (boiling, steaming and microwave methods) was determined by a redox titration using iodine in the presence of starch indicator. This was conducted at Busitema University, Faculty of Science and Education, Biology Laboratory in Uganda. Results: The study revealed that cooking cowpea vegetable using microwave yields the highest concentration of vitamin C (154.8 mg/L), followed by steaming (142.9 mg/L) and boiling yielding the least concentration of vitamin C (130.4 mg/L). Conclusion: The concentration of vitamin C obtained by the three methods of cooking cowpea vegetable has shown that microwaving method of cooking yields the highest concentration of vitamin C followed by steaming method and finally boiling. Further studies should be done to explain the variation of vitamin C concentration in cowpea vegetable when cooked using the above cooking methods. Similar studies should be conducted on other leafy vegetables which are potential sources of Vitamin C.

Effect of Cooking Methods and Temperature on Proximate and Amino Acid Composition of Breakfast Sausage

Aims: The effect of cooking method and temperature on amino acid composition of breakfast sausage (BS) was undertaken in this study. Methodology: Three batches of prepared BS from beef, were randomly allotted to three cooking methods (CM): (boiling, grilling and frying) each at cooking temperatures (CT) of 80, 90 and 100°C to attain internal temperature of 72°C in a completely randomized design. Samples from each treatment were oven-dried and assayed for amino acid and proximate composition using standard procedures. Data obtained was analysed using descriptive statistic and ANOVA at α0.05. Results: Results showed that grilled sausage at 80°C had highest total amino acid profile (3.2%). Grilled sausage at 80°C had highest crude protein (25.58%). Grilled BS at 80°C recorded least fat content (15.99%). Grilled sausage at 80°C had the higher ash (6.66%) and least (1.40%) in boiled sausage at 90°C. Conclusion: Therefore, breakfast sausage could be best grilled at 80°C due to maintain high amino acid profile, crude protein, ash and lower fat content.

Changes in Antioxidant Status between Different Cooking Methods in Eggs Yolk.

Background: The method of cooking causes important changes in quality and safety of food. The purpose of this study was to survey the relation between nutritional- qualitative factors of eggs in different of cooking methods. Methods: The eggs were exposed in different cooking including water cooking, cooking in a microwave and frying. Lipid oxidation, Vitamin E and carotenoid of yolk were measured. Results: The changes in lipid peroxidation were not significant. There was significant change in Vitamin E level in water cooking method. The levels of vitamin E in water cooking and frying method were 0.82±0.05 and 2.6±0.6 mg/g respectively. The carotenoids content also reduced in microwave method. Conclusion: This study showed that significant differences may exist in some nutritional-qualitative factors such as vitamin E and carotenoids levels between common cooking methods of egg. Our findings offer frying as suitable method to maintain their active components.

Study on Sodium Reduction: 'Healthy Restaurant for Sodium Reduction'

This study compared total sodium amounts in 'Healthy Restaurant for Sodium Reduction' menu items located in Seoul, Chungcheong, and Gyeongsang in 2011 and 2012. In addition, this study explored reduced sodium cooking methods in 'Healthy Restaurant for Sodium Reduction'. This study monitored and collected menu samples from a total of 103 restaurants participating in 'Healthy Restaurant for Sodium Reduction' in 2011 and 2012. We also surveyed restaurant employees to identify reduced sodium cooking methods in 2012. The results showed significant reductions in total amounts of sodium in menu items of restaurants located in Seoul, Chungcheong, and Gyeongsang between 2011 (310.8+/-156.8 mg/100g) and 2012 (211.6+/-110.3 mg/100g). Amounts of sodium in all seven foodgroups showed significant reductions between 2011 and 2012: 'Gook/Tang' (from 226.6+/-127.7 mg/100g to 168.5+/-74.3 mg/100g), 'Jjigae/Jeongol' (from 385.8+/-111.7 mg/100g to 257.1+/-82.53 mg/100g), 'Noodle/Dumpling' (from 263.8+/-116.9 mg/100g to 194.1+/-55.6 mg/100g), 'Gui' (from 390.3+/-120.6 mg/100g to 258.8+/-92.7 mg/100g), 'Steamed dish' (from 305.3+/-124.3 mg/100g to 175.6+/-76.6 mg/100g), 'Bob' (from 273.7+/-162.5 mg/100g to 167.1+/-93.1 mg/100g), and 'Stir-fried dish' (from 368.6+/-116.6 mg/100g to 219.0+/-72.4 mg/100g). The survey results showed that responses for 'Reducing salt amount' were 75.7%, responses for 'Using enchovy stock, shrimp, radish, or fruit soup' were 64.1%, and responses for 'Liking the taste because it is bland' were 50%. This study indicates that 'Healthy Restaurant for Sodium Reduction' nutrition policy was successful for reducing sodium contents of restaurant menu items, and also consumers were satisfied with the tastes.

A Study on the menu preferences with school dinner by food service management types in Daegu

The purpose of this study is to present basic data for an improvement of school foodservice by identifying students' preference level for school meal menu. A survey was carried out in two high schools provided with different types of consignment service in Daegu. Study subjects were consisted of 100 high school students from a school with on-site service and 119 students from the other school with external transporting service. More than half of students (54.2% of male and 68.3% of female) had normal weights while 13.5% of male and 30.1% of female students had underweights. 'Taste' and 'family' were the most important factors in meal choices and in eating habits, respectively of all the study subjects. Students who answered to have unbalanced diet (33.0%) were less in school with on-site service than those (56.1%) with external transporting service. Compared with on-site service, preferences for meats fruit and milk were higher and as cooking method, preference for blanching lower but stew, roasting and frying higher in the school with external transporting service. Various types of cooking methods and food materials were better accepted by the students with on-site service than those with external transporting service who preferred meat more exclusively regardless of cooking methods of main dish. Most kinds of kimchi was less liked by the students with external transporting service. It is concluded that low preference for most menus provided by the external transporting service is attributed by limitation in food materials, cooking methods and maintenance of food temperature. The limitation could be overcome by more intensive efforts for developing menus and using more efficient facilities and ultimately by changing meal service system in cooperation with school administrators, dietitians and parents.