Looking for the most efficient method of vegetable processing

So far most people know to eat a lot of vegetables. But is there any way to make better use of vegetables?

One study found that for vegetables, it is important not only how much we eat, but how we cook. The way to process vegetables is related to the amount of phytochemicals (biologically active substances in plants), vitamins and other nutrients.

Many studies show that people who eat a lot of vegetables are at lower risk of heart disease, hypertension, diabetes, eye diseases and even cancer. The latest diet guide gives 5 to 13 servings - about 2.5 to 6.5 cups a day. For those who maintain a 2,000-calorie-a-day diet to maintain weight, it takes about 9 servings, equivalent to 4.5 cups a day (information from Harvard School of Public Health). But how to divide rations?

It is worth noting that it is not always good to eat fresh or processed vegetables simply. According to The British Journal of Nutrition, the researchers produced results from a survey of 198 Germans who are loyal to raw food, meaning that 95% of the food consumed is raw food. Live food has an average vitamin A ratio, and beta carotene ratio is quite high.

But the amount of lycopene in raw food is very low. Lycopene is a carotenoid in tomatoes and red vegetables as one of the most effective antioxidants. Nearly 80% of unprocessed vegetables have lower average levels of lycopene plasma.

Steven K. Clinton, a nutrition researcher and professor of internal medicine at the Ohio State University, said: 'People often mistakenly believe that raw food is better than processed food. For a bit of vegetables, a little processing can be more effective . '

(Photo: Green-england)

The type and amount of nutrients found in vegetables is affected by many factors before we display them on a plate, including the location and method of planting, storage and processing before buying. Then it is up to us. There is no single processing or preparation method to achieve the highest efficiency. Water-soluble nutrients such as vitamins B and C and a group of nutrients called polyphenolic are often lost during processing. For example, research shows that after 6 months frozen cherries will lose about 50% of anthocyanin - beneficial compounds in red, green and vegetable fruits. Fresh spinach takes 64% of vitamin C after cooking. Canned beans and carot take between 85% and 95% of vitamin C (according to the University of California, Davis).

Fat-soluble compounds such as vitamins A, D, E and K along with antioxidant compounds called carotenoids are not lost when exposed to water. Processing also breaks down the thick cell walls of plants to be able to use the interior. That's why processed tomatoes have a higher lycopene content than fresh tomatoes.

In January, the article in Agriculture and Food Chemistry concluded that boiled carrots, zucchini and broccoli are better than stews, fried or eaten raw. Frying is the most inefficient way of processing. But there is also the reverse side. Boiling carrots significantly increases carotenoid levels, but completely loses polyphenols compared to fresh carrots.

The article does not mention the impact of microwave ovens. But a study published in March 2007 in Food Science investigated the impact of food processing methods such as boiling, steaming, using microwaves and pressure cookers on the nutrients in broccoli. (broccoli). Steaming and boiling reduce about 22% to 34% of vitamin C. Processing by pressure or microwave maintains up to 90% of vitamin C in broccoli.

The food that comes with vegetables is also quite important. The study, conducted in Ohio, measured blood levels of people who often eat salsa and salads. When salsa or salad is served with a high-fat avocado or mixed oil, we will absorb 4 times the amount of lycopene, 7 times more lutein and 18 times more beta carotene than when eating non-vegetables. additives or low-fat blending oils.

Fat also increases the flavor of vegetables, which means we will eat more vegetables. This month's issue of The American Journal of Preventive Medicine resulted in interviews of 1,500 high school students about their eating habits and four years after repeating the study. At the age of youth, many factors affect the taste of vegetables. When participants were 20 years old, the main factor affecting the diet with vegetables was their taste. Young people don't like to eat vegetables simply because they don't like its taste.

Dr. Clinton said: 'If you add a little bit of additive such as a bit of salt to make the dish more appealing, we will find it easier to eat and will probably eat more often.' Because nutrients and delicious tastes vary greatly depending on how you prepare them, how to prepare them. It is important to eat a variety of processed vegetables in different ways.

Susan B. Roberts, director of the Metabolic Energy Laboratory at Tufts University's Friedman School of Nutrition, stressed: 'Eating a variety of vegetables is especially important to make us feel like we can eat. more'.