The Very-Very Significant Nutritional Losses In Rice Processing

[Amazoniac]

Soaking and washing rice is great because it removes toxins, but you also lose nutrients.

- Arsenic in cooked rice foods: Assessing health risks and mitigation options

I was concerned about molybdenum since it's rich in it. Losses are considerable, but far from making it the vote.

- Risk and Benefit of Different Cooking Methods on Essential Elements and Arsenic in Rice

"A variety of factors are important in rice preparation and these govern the quality of the cooked rice. For example, the rice-to-water ratio is a significant aspect and optimal use of water in cooking involves using rice-to-water ratios of between 1:1.5 and 1:2.5 [10]. The traditional method used in Southeast Asia involves a rinsing step and cooking rice in excess water (5–6 times the weight of rice), which is later discarded [11]. In the preparation of Jollof rice (a popular Nigerian rice dish), excess water is used to boil the rice until a rubbery texture is achieved, similar to parboiling. Thereafter, the rice is rinsed in cold water and added to tomato sauce and ground cray fish, to be cooked to an edible state [12]."

"[..]simple cooking methods can remove arsenic from the grain [20] and multiple studies suggest that use of excess water for cooking plays an important role as a short-term As removal technique, and a decrease in As of between 15 and 63% has been observed in different studies when rice is cooked with As free water [11,21,22]. However, cooking in excess water also results in the loss of nutrients including essential elements [23]. A loss of 40–75% iron (Fe) depending on the type of rice and cooking technique is reported [23]."

"Overall, we found 4.5%, 30%, and 44% decrease in the arsenic content of rice when cooked with rice-to-water ratios of 1:3, 1:6 (p = 0.004), and 1:10 (parboiling; p < 0.0001), respectively. All the essential elements (except iron, selenium, and copper) incurred a significant loss when rice was cooked using the 1:6 technique: potassium (50%), nickel (44.6%), molybdenum (38.5%), magnesium (22.4%), cobalt (21.2%), manganese (16.5%), calcium (14.5%), selenium (12%), iron (8.2%), zinc (7.7%), and copper (0.2%) and further reduction was observed on parboiling, except for iron. For the same cooking method (1:6), percentage contribution to the recommended daily intake (RDI) of essential elements was highest for molybdenum (154.7%), followed by manganese (34.5%), copper (33.4%), selenium (13.1%), nickel (12.4%), zinc (10%), magnesium (8%), iron (6.3%), potassium (1.8%), and calcium (0.5%). Hence, cooked rice as a staple is a poor source for essential elements and thus micronutrients."

For 100 g/d:

I wonder how turmeric affects its availabllaibility.

- Cooking Losses of Minerals in Foods and Its Nutritional Significance
- A type of post-harvest loss: nutritional losses during washing and cooking of rice

- Effects of washing, soaking, and domestic cooking on cadmium, arsenic , and lead bioaccessibilities in rice

Reduction of pesticides after washing and cooking, both is in relation to its unprocessed state:
- The Effects of House Cooking Process on Residue Concentrations of 41 Multi-Class Pesticides in Rice

 

[Dave Clark]

Didn't the Japanese find out years ago that processing of rice caused thiamine deficiency in those consuming white rice, I guess as opposed to brown rice?

 

[Tristan Loscha]

Soaking and washing rice is great because it removes toxins, but you also lose nutrients.

- Arsenic in cooked rice foods: Assessing health risks and mitigation options

View attachment 15417​

I was concerned about molybdenum since it's rich in it. Losses are considerable, but far from making it the vote.

- Risk and Benefit of Different Cooking Methods on Essential Elements and Arsenic in Rice

"A variety of factors are important in rice preparation and these govern the quality of the cooked rice. For example, the rice-to-water ratio is a significant aspect and optimal use of water in cooking involves using rice-to-water ratios of between 1:1.5 and 1:2.5 [10]. The traditional method used in Southeast Asia involves a rinsing step and cooking rice in excess water (5–6 times the weight of rice), which is later discarded [11]. In the preparation of Jollof rice (a popular Nigerian rice dish), excess water is used to boil the rice until a rubbery texture is achieved, similar to parboiling. Thereafter, the rice is rinsed in cold water and added to tomato sauce and ground cray fish, to be cooked to an edible state [12]."

"[..]simple cooking methods can remove arsenic from the grain [20] and multiple studies suggest that use of excess water for cooking plays an important role as a short-term As removal technique, and a decrease in As of between 15 and 63% has been observed in different studies when rice is cooked with As free water [11,21,22]. However, cooking in excess water also results in the loss of nutrients including essential elements [23]. A loss of 40–75% iron (Fe) depending on the type of rice and cooking technique is reported [23]."

"Overall, we found 4.5%, 30%, and 44% decrease in the arsenic content of rice when cooked with rice-to-water ratios of 1:3, 1:6 (p = 0.004), and 1:10 (parboiling; p < 0.0001), respectively. All the essential elements (except iron, selenium, and copper) incurred a significant loss when rice was cooked using the 1:6 technique: potassium (50%), nickel (44.6%), molybdenum (38.5%), magnesium (22.4%), cobalt (21.2%), manganese (16.5%), calcium (14.5%), selenium (12%), iron (8.2%), zinc (7.7%), and copper (0.2%) and further reduction was observed on parboiling, except for iron. For the same cooking method (1:6), percentage contribution to the recommended daily intake (RDI) of essential elements was highest for molybdenum (154.7%), followed by manganese (34.5%), copper (33.4%), selenium (13.1%), nickel (12.4%), zinc (10%), magnesium (8%), iron (6.3%), potassium (1.8%), and calcium (0.5%). Hence, cooked rice as a staple is a poor source for essential elements and thus micronutrients."

For 100 g/d:
View attachment 15418​

I wonder how turmeric affects its availabllaibility.

- Cooking Losses of Minerals in Foods and Its Nutritional Significance
- A type of post-harvest loss: nutritional losses during washing and cooking of rice

- Effects of washing, soaking, and domestic cooking on cadmium, arsenic , and lead bioaccessibilities in rice

Reduction of pesticides after washing and cooking, both is in relation to its unprocessed state:
- The Effects of House Cooking Process on Residue Concentrations of 41 Multi-Class Pesticides in Rice

Good Post.And they dont touch upon Vitamin-losses and Vitamin-destruction.Yes,Beriberi is white-rice-disease unfortunately.

 

[Tristan Loscha]

.

 

[ecstatichamster]

it does cause thiamine deficiency but everyone loves white rice compared to brown rice. Why is that?

White rice has lower endotoxin creating ability. It is far more digestible and lacks some of the anti-nutrients and PUFA that are in the rice bran...

 

[Amazoniac]

it does cause thiamine deficiency but everyone loves white rice compared to brown rice. Why is that?

White rice has lower endotoxin creating ability. It is far more digestible and lacks some of the anti-nutrients and PUFA that are in the rice bran...

May be that a well-nourished person can be more judicious in choices contrary to those who are less so, with the distaste for antinutrients decreasing as the needs for nutrients increase. Our dear rodent must be in good shape.

- Mineral Metabolism on Rice Diets

 

[Waremu]

If well cooked greens or some fruit are added to the white rice, as is done traditionally in many cultures, then I think that can more than make up for the nutrient loss in the rice without many extra calories. I think eating rice that way is probably the sweet spot as far as cost-benefit goes, for those who want to maximize nutrition while minimizing anti-nutrients/PUFA. For example, a number of greens, such as Bok Choy, has an amount of nutrition that is very comparable to brown rice, or maybe is altogether better, calorie for calorie. But if a well tolerated starch which has good nutrition and less anti-nutrients is my goal, I probably would go with purple sweet potatoes over white rice.

 

[Gone Peating]

"Percolating water" apparently removes all arsenic without removing any of the vitamins and minerals

But what exactly is percolating water

 

[Dave Clark]

"Percolating water" apparently removes all arsenic without removing any of the vitamins and minerals

But what exactly is percolating water

Well I suppose it probably means the same thing that goes on with a coffee percolator, hot water run over the rice multiple times. I don't know how you could do that other than get an old style coffee percolator and put the rice in the coffee grounds basket and let it rip. I don't know if they make them anymore since it isn't a popular way to make coffee (it was the thing when I was growing up), but you may find one at a flea market or yard sale.

 

[Amazoniac]

- Anti-Peat - Grant Genereux's Theory Of Vitamin A Toxicity

- Effect of food preparation using naturally-contaminated ground water from La Pampa, Argentina: Estimation of elemental dietary intake from rice and drinking water (from the first link of this thread)

Spoiler

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- Effects of household cooking processes on mineral, vitamin B, and phytic acid contents and mineral bioaccessibility in rice

The effects of washing, soaking, and cooking (ordinary cooking, high-pressure cooking, and microwave cooking) on thiamine, riboflavin, phytic acid (PA), and mineral contents (Mg, Ca, Mn, Zn, and Fe) of different cultivars rice, Xinfeng 2 and T-You 15, were investigated. Washing caused a significant loss in vitamin B, PA, and mineral contents, whereas, soaking only decreased the thiamine content. Moreover, cooking decreased the vitamin B and PA contents, and high-pressure cooking exerted more remarkable effects than those of ordinary and microwave cooking. Furthermore, washing and soaking increased the Zn and Ca bioaccessibilities, however, cooking improved the bioaccessibilities of Mg, Fe, and Ca, but decrease those of Zn and Mn. Therefore, vitamin and mineral losses caused by excessive washing should be given attention. Cooking processes in relatively low temperature may also be beneficial to the nutritive properties of vitamins and minerals.