蛋白質(zhì)在營(yíng)養(yǎng)健康中的重要性是毋庸置疑的。尤其是在目前的新冠肺炎阻擊戰(zhàn)中，大家認(rèn)識(shí)到，充足的蛋白質(zhì)對(duì)于維持正常的免疫功能、增強(qiáng)抵抗力非常重要。
The importance of protein in nutritional health is indisputable. Especially in the current COVID-19 battle, it has been recognized that adequate protein is important for maintaining normal immune function and strengthening resistance.
從來(lái)源上，蛋白質(zhì)可分為植物蛋白和動(dòng)物蛋白兩大類。
From the source, protein can be divided into plant protein and animal protein.
不同來(lái)源的蛋白質(zhì)在很多方面存在巨大差異。對(duì)這些差異的了解，可以幫助我們合理選用蛋白質(zhì)，更好的維持和改善健康（大豆蛋白是產(chǎn)量最大的植物蛋白，大豆及其制品也是我們傳統(tǒng)膳食中的重要組成部分，因此，以下介紹主要引用和參考大豆蛋白）。
Proteins from different sources vary greatly in many ways. Understanding these differences can help us choose protein rationally and maintain and improve our health better (soybean protein is the most productive plant protein, and soy and its products are also an important part of our traditional diet. Therefore, the following introduction mainly refers to soy protein).
植物蛋白和動(dòng)物蛋白的主要區(qū)別包括：Key differences between plant and animal proteins include:
結(jié)構(gòu)和存在方式不同 Different structures and modes of existence
從蛋白質(zhì)分子看，蛋白質(zhì)是由一個(gè)個(gè)氨基酸連成的一條肽鏈（一級(jí)結(jié)構(gòu)），肽鏈形成螺旋或折疊（二級(jí)結(jié)構(gòu)），進(jìn)一步纏繞形成基團(tuán)（三級(jí)結(jié)構(gòu)），各種基團(tuán)按一定模式組合在一起（四級(jí)結(jié)構(gòu)）。
From the protein molecule, the protein is a peptide chain of amino acids (the first class structure), the peptide chain forms a spiral or fold (secondary structure), further winding formation group (tertiary structure), various groups are grouped together in a certain pattern (class 4).
植物蛋白的二級(jí)結(jié)構(gòu)以β-折疊為主，而動(dòng)物蛋白以α-螺旋為主。從蛋白質(zhì)在食物中的存在狀態(tài)看，植物蛋白往往與碳水化合物（非淀粉多糖和膳食纖維）結(jié)合在一起，動(dòng)物蛋白則主要與脂肪共存。
The secondary structure of plant protein is dominated by the “β-folding”, and animal protein is dominated by the “α-spiral”. From the presence of protein in food, plant protein is often combined with carbohydrates (non-starch polysaccharide and dietary fiber), and animal proteins mainly coexists with fat.
這些因素都會(huì)帶來(lái)植物蛋白和動(dòng)物蛋白營(yíng)養(yǎng)價(jià)值上的差異。比如，動(dòng)物蛋白的攝入，常常伴隨大量飽和脂肪的攝入；食用大豆，既有大豆蛋白，也包括膳食纖維、異黃酮、大豆磷脂等功能性成分。
All these factors will bring about the difference in nutritional value between plant protein and animal protein. Animal protein, for example, is often accompanied by a high intake of saturated fats. Edible soybean includes both soybean protein and functional components such as dietary fiber, isoflavone and soybean phospholipid.
人體對(duì)蛋白質(zhì)的需求，首先是需要有足夠的量（成年人每天每公斤體重需要1克），其次是需要保證蛋白的“質(zhì)”，能充分滿足人體營(yíng)養(yǎng)健康需求的蛋白質(zhì)才是優(yōu)質(zhì)的蛋白質(zhì)。
The human body’s demand for protein, first of all, needs to have enough amount (adults need 1 gram per kilogram of body weight every day). Second, the protein quality should be ensured that can fully satisfy human body nutrition health demand.
我們需要膳食蛋白質(zhì)提供20種氨基酸；這些氨基酸，如果不夠用的話，有些可以“借用”（身體利用其他營(yíng)養(yǎng)素直接或間接合成非必需氨基酸），有些必需自己從食物中獲取（9種必需氨基酸是借不到的）。
We need dietary protein to provide 20 amino acids; If there are not enough of these amino acids, some can be “borrowed”(the body synthesizes non-essential amino acids or indirectly from other nutrients), and some must be obtained from food (the nine essential amino acids cannot be borrowed).
消化率不同 Different digestibility
消化率是指蛋白質(zhì)被消化酶分解的程度以及消化后的氨基酸、肽被吸收的程度。食物被機(jī)體吸收的越多，營(yíng)養(yǎng)價(jià)值越高。一般雞蛋蛋白常被用作參考蛋白，其消化率為100%。衡量蛋白質(zhì)質(zhì)量的公認(rèn)指標(biāo)是“蛋白質(zhì)消化率校正的氨基酸評(píng)分（PDCAAS）”，滿分為1。
Digestibility refers to the degree of decomposition of protein by digestive enzymes and the degree of absorption of amino acids and peptides after digestion. The more food is absorbed by the body, the higher its nutritional value. General egg protein is often used as a reference protein with a digestibility of 100%. The accepted measure of protein quality is the “Protein Digestibility Corrected Amino Acid Score”（PDCAAS）,with a score of 1.
目前并列第一的四名選手是：乳清蛋白，酪蛋白，雞蛋蛋白，以及大豆分離蛋白。PDCAAS為1的意思是，該蛋白含有人體所需的所有9種必需氨基酸，并且每一種都達(dá)到所需的量（腦海里應(yīng)該馬上有一只木桶，有9片板子，任何一片短了都裝不滿水）。換句話說，如果你任性，只食用一種蛋白質(zhì)還想要身體健康，那么只有選PDCAAS為1的蛋白質(zhì)才有可能。
The four players currently tied to the first one are: whey protein, casein, egg protein, and soy protein. The PDCAAS 1 means that the protein contains all the nine necessary amino acids that the body needs, and every one reaches the amount required (there should be a wooden bucket in your head, with nine boards, and any one of them is short of the water). In other words, if you’re capricious and want to eat just one protein and still be healthy, the only way you can do that is by choosing a protein with PDCAAS 1.
植物蛋白常常與植酸、蛋白酶抑制劑、植物血凝素和鞣酸等影響蛋白質(zhì)消化的抗?fàn)I養(yǎng)因子共存。加上結(jié)構(gòu)上的差異，植物蛋白的消化率往往比動(dòng)物蛋白要低。所以，食物加工對(duì)于提高植物蛋白的消化利用率特別重要。僅只是將食物煮熟，就能將蛋白質(zhì)的消化率提高18%。大豆粉的蛋白消化率只有80%，而大豆分離蛋白能達(dá)到98%。
Plant proteins often coexist with phytic acid, protease inhibitors, phytohemagglutinin, tannic acid and other antinutritional factors that affect digestion. Coupled with structural differences, plant proteins tend to have a lower digestibility than animal proteins. Therefore, food processing is particularly important for improving the digestibility of plant protein. Just by cooking food, you can increase protein digestibility by 18%. Soybean meal has a protein digestibility of only 80%, while soy protein isolate can reach 98%.
健康作用不同 Different health effects
與動(dòng)物蛋白相比，植物蛋白有更多健康益處，包括降低心血管病、2型糖尿病和某些腫瘤的風(fēng)險(xiǎn)等。
Compared with animal proteins, plant proteins have many health benefits, including a reduced risk of cardiovascular disease, type 2 diabetes and some cancers.
比如，牛奶蛋白有控制體重和降低甘油三酯的作用，而大豆分離蛋白與牛奶蛋白相比，降血脂作用更明顯（甘油三酯、總膽固醇和低密度脂蛋白膽固醇都能降）；大豆蛋白還有降血壓、提高胰島素敏感性、降低體內(nèi)炎癥反應(yīng)水平等的作用。
For example, milk protein has the function of controlling body weight and lowering triglycerides, while isolated soy protein has a more obvious effect on lowering blood lipids (triglycerides, total cholesterol and LDL-C can all be reduced) than milk protein. Soy protein can also lower blood pressure, improve insulin sensitivity, and reduce the level of inflammation in the body.
已有包括美國(guó)FDA在內(nèi)的13個(gè)國(guó)家和地區(qū)的管理部門作出認(rèn)證：每天食用25克大豆蛋白有降低心臟病風(fēng)險(xiǎn)的作用。
Regulatory authorities in 13 countries and territories, including the U.S. FDA, have certified 25 grams of soy protein a day to reduce the risk of heart disease.
對(duì)環(huán)境影響和可持續(xù)性不同 ?Different environmental impact and sustainability
植物蛋白與動(dòng)物蛋白相比，環(huán)保和可持續(xù)性方面的優(yōu)勢(shì)非常明顯。例如，生產(chǎn)1公斤大豆分離蛋白，向環(huán)境中排放的二氧化碳是2.4公斤，而生產(chǎn)同量牛肉蛋白質(zhì)是178公斤！
Compared with animal protein, plant protein has obvious advantages in environmental protection and sustainability. For example, producing 1kg of isolated soy protein releases 2.4kg of carbon dioxide into the environment, while producing the same amount of beef protein is 178kg.
雞肉和豬肉等其他動(dòng)物蛋白的溫室氣體排放量也都遠(yuǎn)遠(yuǎn)高于大豆。生產(chǎn)1公斤大豆分離蛋白要占用8平方米的耕地一年時(shí)間，牛肉蛋白則是1311平方米！
Other animal proteins such as chicken and pork, also have much higher greenhouse gas emissions than soy. It takes 8 square meters of farmland a year to produce 1 kilogram of isolated soy protein, and 1311 square meters of beef protein.
過去幾年中，亞馬遜雨林燃燒、澳大利亞大火、歐洲夏季高溫、南北極冰川融化等等，已經(jīng)讓越來(lái)越多的人認(rèn)識(shí)到減少溫室氣體排放的迫切性！
In the past few years, the burning of the Amazon rainforest, the fires in Australia, the high summer temperatures in Europe, the melting of the glaciers in both the North and the South etc. have made more and more people realize the urgency of reducing greenhouse gas emissions.
我們?cè)撊绾螐娘嬍持蝎@得足量蛋白質(zhì)呢？以下是關(guān)于蛋白質(zhì)攝入量的一些具體建議：
How can we get enough protein from our diet?? Here are some specific recommendations for protein intake:
足量 Adequate intake
不同人群對(duì)蛋白質(zhì)的需求是不同的。通常，成年人每公斤體重每天需要1克蛋白質(zhì)，老年人則需要適當(dāng)增加到1.2克甚至更高；不同年齡段的兒童對(duì)蛋白質(zhì)的需求不一樣：3-5歲的兒童每天需要30克蛋白質(zhì)，6歲35克，7-8歲40克，9歲45克，10歲50克，14-18歲是對(duì)蛋白質(zhì)需求最大的時(shí)期，男孩每人每天需要75克，女孩60克。患病的人群則需要根據(jù)具體情況決定。人體對(duì)蛋白質(zhì)的需求量，并不是針對(duì)某種蛋白質(zhì)設(shè)定的，因此，不管以動(dòng)物蛋白為主還是植物蛋白為主，都應(yīng)該攝入足量的蛋白質(zhì)。
Different populations have different protein requirements. In general, adults need 1 gram of protein per kilogram of body weight per day, while the elderly need a modest increase to 1.2 grams or more. Protein needs vary by age: 30 grams per day for 3-5 year olds, 35 grams per day for 6-year olds, 40 grams per day for 7-8 year olds, 45 grams per day for 9-year olds, and 50 grams per day for 10-year olds. The peak protein needs are 14 to 18 year olds, 75 grams per day for boys and 60 grams per day for girls.? Who gets sick depends on the circumstances. Human body is right protein demand, not be in the light of some kind of protein setting, accordingly, no matter give priority to with animal protein or plant protein, should absorb sufficient amount of protein.
搭配?Collocation
蛋白質(zhì)來(lái)源多樣化，有助于通過互補(bǔ)保證身體獲得所需的各種氨基酸。比如，谷物蛋白中賴氨酸含量相對(duì)較低，豆類蛋白中則含硫氨基酸較少，而乳清蛋白中亮氨酸含量較高等等。強(qiáng)調(diào)蛋白質(zhì)來(lái)源多樣化，其實(shí)是膳食多樣性在蛋白質(zhì)上的應(yīng)用和體現(xiàn)。比如，植物蛋白與動(dòng)物蛋白的搭配；多種植物蛋白(比如多種豆類）或多種動(dòng)物蛋白（畜、禽和魚類）之間的搭配等等。
Diversity of protein sources helps ensure that the body gets all the amino acids it needs through complementation. For example, grain protein is relatively low in lysine, soy protein is low in sulfur amino acids, whey protein is high in leucine etc. Emphasizing the diversity of protein sources is actually the application and embodiment of dietary diversity in protein. For example, the combination of plant protein and animal protein; combination of plant proteins (such as beans) or animal proteins (livestock, poultry and fish), etc.
在實(shí)施《中國(guó)居民膳食指南》中“每天食用12種，每周25種”不同食物的推薦中，注意蛋白含量豐富的食品的搭配，有助于實(shí)現(xiàn)蛋白營(yíng)養(yǎng)的均衡。某些情況下，挑選適當(dāng)來(lái)源的蛋白質(zhì)和合理搭配更有利于健康。比如，慢性腎功能不全的病人需要適當(dāng)降低蛋白質(zhì)攝入量，大豆分離蛋白因其降血脂、降血壓、抗氧化和對(duì)鈣磷代謝調(diào)節(jié)上的優(yōu)勢(shì)，可能更適合他們作為蛋白質(zhì)來(lái)源。而對(duì)運(yùn)動(dòng)后肌肉的合成與恢復(fù)，大豆分離蛋白和牛奶蛋白以適當(dāng)比例混合效果更好。
In the implementation of the “Dietary Guidelines for Chinese Residents” recommended to eat 12 kinds of different foods a day, 25 kinds a week, pay attention to the collocation of food rich in protein, which is conducive to the balance of protein nutrition. In some cases, choosing the right sources of protein and mixing them together is better for your health. For example, patients with chronic renal insufficiency need to reduce protein intake appropriately, and soy protein isolate may be more suitable for them as a protein source because of its advantages in lowering blood lipids, lowering blood pressure, anti-oxidation and regulating calcium and phosphorus metabolism. For muscle synthesis and recovery after exercise, the mixture of isolated soy protein and milk protein in proper proportion is better.
補(bǔ)充 Supplement
膳食因素在健康中的作用非常大，對(duì)于心血管病、2型糖尿病和腫瘤等慢性病，膳食因素是最大的危險(xiǎn)因素。但很遺憾，還是有很多人沒有形成良好的膳食習(xí)慣。比如兒童青少年挑食的問題越來(lái)越嚴(yán)重。而老年人，則往往因?yàn)槟挲g的增加和生理機(jī)能降低后未能主動(dòng)作出必要的膳食調(diào)整而導(dǎo)致蛋白質(zhì)攝入不足等“隱性營(yíng)養(yǎng)不良”。
Dietary factors play a very important role in health. For chronic diseases such as cardiovascular disease, type 2 diabetes and tumor, dietary factors are the biggest risk factors.??? But unfortunately, there are still many people who do not form good eating habits. For example, children and teenagers are becoming more and more picky about food. And old people, often because the increase of age and physiological function are reduced, the necessary dietary adjustment fails to be made actively and bring about protein intake to wait for inadequacy “recessive malnutrition”.
所以，在未能通過膳食實(shí)現(xiàn)均衡充足的營(yíng)養(yǎng)的時(shí)候，有必要額外補(bǔ)充一些蛋白質(zhì)。
Therefore, it is necessary to supplement some protein when balanced and adequate nutrition is not achieved through the diet.
可以選取大豆分離蛋白或大豆分離蛋白混合牛奶蛋白的產(chǎn)品補(bǔ)充蛋白質(zhì)。大豆分離蛋白在心臟健康、降血脂、降血壓、延緩腎臟功能下降，以及環(huán)保方面有動(dòng)物蛋白不可比擬的優(yōu)勢(shì)。補(bǔ)充多少為宜，應(yīng)該咨詢醫(yī)生或營(yíng)養(yǎng)師，視自己的情況而定?，F(xiàn)在市面上的多數(shù)蛋白粉產(chǎn)品，推薦的補(bǔ)充量多數(shù)在每天10-20克之間。
Soy protein isolate or soy protein isolate mixed with milk protein products can be selected for protein supplement.? Soy protein isolate has incomparable advantages in heart health, lowering blood lipids, lowering blood pressure, delaying kidney function decline, and environmental protection.? How much supplement is appropriate, should consult a doctor or dietitian, depending on their own situation.? For most protein powder products on the market today, the recommended amount of supplement is between 10 and 20 grams per day.
總之，植物蛋白是人們膳食蛋白質(zhì)的重要來(lái)源。目前，人類食用的蛋白質(zhì)還是以植物來(lái)源為主，在亞洲和非洲尤其如此。雖然歐美發(fā)達(dá)國(guó)家的飲食中動(dòng)物蛋白多于植物蛋白，但近年來(lái)，植物蛋白受到越來(lái)越多的青睞，一股強(qiáng)勁的膳食“植物風(fēng)”已吹遍全世界。作為一個(gè)具有悠久植物性膳食歷史和優(yōu)良膳食傳統(tǒng)的國(guó)家，我們研究和利用植物蛋白的意義更加重大。
In a word, plant protein is an important source of dietary protein.? At present, the majority of protein consumed by humans comes from plant sources, especially in Asia and Africa.? Although the animal protein in the diet of Euramerican developed country is more than plant protein, but in recent years, plant protein gets more and more favour, a strong meal “plant wind” already blown all over the world.? As a country with a long history of plant-based diet and an excellent dietary tradition, it is of great significance for us to study and use plant protein.
來(lái)源： 食品工業(yè)科技