Bamboo: Global Occurrence and Its Significance as Food and Related Products

Abstract

Bamboo has recently garnered international recognition for its nutritional and medicinal properties, which contribute significantly to the culinary, pharmaceutical, and cosmeceutical sectors. Every component of the bamboo plant—rhizome, culm, bark shavings, shoots, leaves, roots, and seeds—possesses useful applications. Bamboo shoots, as a type of food, have been consumed for a long time due to their nutritional and edible qualities, as well as their economic value. Other parts of bamboo, such as leaves and culms, can also be used in food applications. Commercial markets in various countries offer a variety of bamboo-based products, including those that are dried, fermented, pickled, and thermally processed. This article provides an overview of the use of all edible bamboo parts as foods and related products as well as their nutritional benefits. A wide range of traditional food products derived from bamboo, including industrial products and some novel products, was investigated. It is possible that the promotion of bamboo as a staple food could offer substantial promise in addressing the worldwide concerns regarding hunger, food insecurity, and environmental degradation.

1. Introduction

Bamboo is a giant grass that belongs to the family Poaceae, found mostly in moist deciduous, semi-evergreen, tropical, subtropical, and temperate areas of forest. It is one of the fastest-growing and oldest plants on Earth [1], being a long-lived, strong, versatile, and highly renewable woody-stemmed perennial species of grasses [2]. Throughout human history, from prehistoric times to the present day, bamboo has been an indispensable tool [3]. As a result, the economic, social, and cultural conditions of people in tropical nations are intricately related to bamboo [4]. Bamboo species are used for a variety of economic purposes, such as building materials, food, fuel, biochar (charcoal made from biomass), and fiber for paper or textiles [5,6,7,8,9,10,11].

Water shortages, rising food prices, and other socio-economic difficulties are only a few of the new challenges that are posing serious dangers to global agriculture and food security, especially for low-income populations in arid regions [12]. The use of bamboo is crucial in solving those problems. Because of its adaptability and versatility, it contributes to worldwide efforts to reduce the effects of climate change [13]. Additionally, bamboo can be utilized as a substitute for timber in forest ecosystems, and it aids in controlling erosion and protecting watersheds. Due to its low pesticide and fertilizer needs, bamboo is a cost-effective crop to grow [14].

Bamboo has recently garnered international recognition for its nutritional and medicinal properties, significantly contributing to the culinary, pharmaceutical, and cosmeceutical sectors [3]. Every component of the bamboo plant, including the rhizome, culm, bark shavings, shoots, leaves, roots, and seeds, possesses clinical applications [13]. Bamboo shoots have been used as a source of food for a very long time, and they have recently garnered the attention of both scientists and industry professionals due to their potential as a sustainable nutrition resource that can potentially meet the requirements of future populations and guarantee food security [8]. The fact that bamboo shoots are low in fat and contain a high concentration of proteins, fibers, minerals, vitamins, and a wide variety of bioactive components makes them extremely beneficial in terms of their nutritional value and the health benefits they offer [15].

In the past few years, there has been a resurgence of interest in bamboo, which has given rise to innovative research and development initiatives that are designed to exploit its maximum potential. The critical role of bamboo in achieving sustainable development objectives, alleviating hunger, and ensuring good health and well-being is being acknowledged by stakeholders across sectors, from policy advocacy to value-added products. Previous studies have focused on the utilization and nutritional aspects of bamboo shoots, which are bamboo’s main edible part. However, other parts of bamboo also play a significant role in providing food and nutrition security. This review explores the profound significance of bamboo, in all its parts, ensuring the significance of their food uses.

2. Global Scenarios of Bamboo

The Poaceae family is divided into 12 subfamilies, with bamboo belonging to the Bambusoideae subfamily. There are three clades, or tribes, within the Bambusoideae subfamily: Olyreae, Bambuseae, and Arundinarieae. Olyreae refers to New World herbaceous species, whereas Bambuseae and Arundinarieae are tropical and temperate woody bamboos, respectively [16]. Bamboo can be divided into two main categories: running (monopodial or leptomorph) and clumping (sympodial or pachymorph), according to the shape and spreading patterns of the rhizomes [17]. Globally, there are over 1640 bamboo species across 123 genera, with more than 1000 species located in Asia, encompassing a total area of 24.9 million hectares, which represents 71% of the world’s bamboo coverage [8,17,18]. The largest national complement of bamboo species is in China, which has about 600 described species, followed by India (102 species) and Japan (84 species) [4]. Native bamboo species are distributed mainly in Asia, America, and Africa, but Europe is unable to claim any native bamboo species. The Asia–Pacific bamboo region is the world’s largest bamboo region.

Presently, bamboo has emerged as one of the most important renewable resources with multipurpose uses. The annual demands for bamboo have already exceeded the annual yields across the world [16]. The global forest area is shrinking rapidly, but the bamboo forest area is growing at a rate of 3% per year, making it a good substitution for wood [18].

Bamboo products worth over USD 3.054 billion were traded internationally in 2019 [19]. With a total of USD 2.469 billion, the Asia–Pacific area was the undisputed leader in bamboo product exports. Europe came in second with USD 297 million, North America came in third with USD 265 million, and Africa came in at USD 19 million. Regarding imports, the total amount of global imports was USD 2.641 billion. The top three regions for bamboo product imports are the Asia–Pacific area, Europe, and North America. These regions purchased 812 million, 836 million, and 882 million bamboo products from outside, respectively. China continues to dominate the global bamboo market, with exports of USD 289 million leading the EU-27 (the remaining 27 EU member states following the UK’s exit from the EU). The top three countries that import bamboo products are the United States (29%), Japan (12%), and the European Union (27%) [16,19].

In terms of edible bamboos, not all species are suitable for edible purposes. Only 26 bamboo species are used for edible purposes in the Asia–Pacific region [20]. Edible bamboo species differ from country to country [21,22,23,24]. Figure 1 shows the shoot appearances of common edible bamboo species from both clumping and running types.

3. Utilizations of Bamboo Components

All bamboo parts can be fully utilized in different ways [25]. The sheath and rhizome are suitable for artefacts and handicrafts. The young shoot is the most common part for consumption as foods [8,15,24]. The culm at the base is suitable for charcoal [11]. The culm in the middle can be used as a component in walling and flooring [26]. The upper portion of the culm is usable for the production of artefacts, toothpicks, chopsticks, carpets, and blinds [16]. The top of the culm is suitable for scaffolding, and the twigs are used for making cloth and brooms. Young bamboo culm can be used for starch extraction, and fiber is a by-product of starch extraction [27]. The leaves serve as fodder and manure. The young leaves can be used as bamboo tea [28]. Bamboo seeds contain starch and can be consumed in a similar way to grain [29]. Leftover material from processed bamboo does not need to be disposed of; rather, it can be used for fiber boards and fuel. Furthermore, contemporary pharmacological formulations produced from bamboo and their extractions of bioactive compounds from various bamboo parts have been introduced for the treatment of numerous health-related issues [3]. Bamboo borer or the larva of the moth, an edible insect, can be obtained from the bamboo culm [30]. Figure 2 illustrates the utilization of bamboo as foods and related products.

4. Nutritional Aspects and Health Benefits

The nutritional aspects and health benefits of bamboo have been extensively studied and reviewed [15,20,31]. Research on this aspect of bamboo has received significant attention. This manuscript explores the significance of bamboo as a food source and for related products, specifically focusing on the production from all parts of bamboo. The nutrition and health benefits are briefly summarized.

4.1. Nutrient Compositions of Bamboo Shoots

Bamboo shoots are rich in carbohydrates, vitamins, and minerals, while being low in fat and cholesterol. The protein concentrations in the shoots vary from 1.49 to 4.04 g/100 g on a wet basis and from 21.1 to 25.8 g/100 g on a dry basis. Seventeen amino acids were identified, including essential amino acids: lysine, serine, methionine, histidine, isoleucine, leucine, and phenylalanine [21,32]. Polysaccharides, oligosaccharides, and monosaccharides are classified as carbohydrates in the shoots. Bamboo branches consist mostly of cellulose, hemicellulose, and starch, along with several minor complex polysaccharides, such as glycoproteins. The carbohydrate content of bamboo seedlings varies by species and is often quantified at 1.90 to 5.10 g/100 g on a wet basis. Nevertheless, specific species may possess up to 9.94 g/100 g on a wet basis [21].

Notably, dietary fiber in bamboo shoots, which is mostly insoluble dietary fiber, accounts for 60–90% of their total carbohydrate [27,33]. Total dietary fiber in bamboo shoots varied from 19.3 to 35.5 g/100 g on a dry basis. For lipids, bamboo shoots are characterized by a substantially low-fat content ranging from 0.30 to 3.97 g/100 g on a wet basis [34,35]. More importantly, bamboo shoots are rich in non-polar lipids, glycolipids, and phospholipids, with a ratio of 17:27:56 [20]. Both macro- and micro-elements are found in bamboo shoots and include K, P, Na, Ca, and Mg (macro-elements) and Co, Cu, Ni, Mn, Se, Fe, and Zn (micro-elements) [36]. Bamboo shoots also contain vitamins C and E, in the ranges of 1.0–7.3 mg/100 g on a wet basis and 0.22–0.91 mg/100 g on a wet basis, respectively [15].

4.2. Nutrient Compositions of Bamboo Leaves

Bamboo leaves have been used for a variety of food products as they are also rich in nutrients [37,38]. On an average dry basis, bamboo leaf tissue contained 12.92 g/100 g protein with relatively high percentages of Leu (8.97%) and Pro (7.98%) and low percentages of Try (1.69%) and His (2.01%). Crude fiber of bamboo leaves was reported to be 18–34 g/100 g on a dry basis [39]. Bamboo leaves also contained relatively high concentrations of K and Ca with 12.17 and 5.37 mg/g, respectively, while Mn and Fe were micro-elements found in the leaves, with values of about 388.76 and 123.19 µg/g, respectively. Low concentrations of Bo (7.8 µg/g) and Zn (28.56 µg/g) were also reported [37,40,41]. The crude protein, acid detergent lignin, and neutral detergent-soluble and non-structural carbohydrates of bamboo leaves from 12 species growing in the bamboo fields of Himachal Pradesh ranged from 14.61 to 20.39, 4.87 to 9.43, 21.47 to 34.62, and 1.10 to 12.06 g/100 g, respectively [41,42].

4.3. Health Benefits

Phytoconstituents derived from bamboo leaves, shoots, and roots encompass several bioactive compounds, including phytosterols and glucosinolates, which provide numerous health benefits [43,44]. In Ayurveda, bamboo leaves are noted for their role in creating an immunity booster; additionally, bamboo leaves, shoots, culms, and roots are utilized in traditional Chinese medicine to treat various ailments, including cooling, calming, and phlegm resolution [45]. Additionally, they are utilized as an anti-inflammatory medication in traditional medicinal practices of Japan and Korea [46]. Recent literature on the therapeutic qualities of bamboo has emphasized its antioxidant, hypolipidemic, prebiotic, antidiabetic, anti-obesity, anti-inflammatory, antihypertensive, and antimicrobial activity [3,47,48]. The antioxidant properties of bamboo shoots mostly stem from their ascorbic acid and phenolic components, which demonstrate significant inhibition of lipid oxidation, remarkable radical scavenging abilities, and comparable reducing capabilities against oxidative substances [3]. Indigestible carbohydrates, such as dietary fiber and non-starch polysaccharides, were pivotal in the hypolipidemic, prebiotic, antidiabetic, and anti-obesity effects of bamboos [15].

4.4. Safety Concerns of Bamboo Shoots

In addition to the nutrients they contain, fresh bamboo shoots might be harmful due to the presence of tannin, oxalate, heavy metals, and cyanogenic substances (cyanides) [49]. The cyanides present in bamboo shoots are degradable organic cyanides referred to as cyanogenic glycosides. Bamboo shoots contain the cyanogenic glycoside taxiphyllin, a p-hydroxylated mandelonitrile tiglochinin [50]. The cyanide content in young bamboo shoots varies with plant type and age, ranging from 32 to 1951 mg/kg on a wet basis [15].

Fortunately, there have been no reports of cyanide poisoning from eating bamboo shoots since these plants undergo a series of processing steps that remove cyanogen, including soaking, boiling, drying, fermenting, and steaming [50,51]. Processed bamboo shoots meet safety standards for consumption due to the fact that cyanogenic glycosides are typically concentrated in the outer layers of bamboo shoots. By peeling off the outer layers and using washing and soaking to dilute, the total amount of cyanides can be significantly reduced. In addition, cyanogenic glycosides are unstable in water. Prolonged soaking or boiling can promote the hydrolysis of cyanogenic glycosides, breaking them down into non-toxic substances. Specific microorganisms can also convert cyanides into other harmless metabolic products during fermentation [49]. Most processing techniques can significantly diminish the antinutrients present in bamboo shoots to a safe level. Among all the processing techniques, fermentation is the most effective approach [50].

5. Bamboo as Foods

Bamboo serves as a significant food source for both people and animals. Two types of animals are fully dependent on bamboo as their foods: the endangered giant panda (indigenous to China) and the golden lemur (endemic to Madagascar). The edible components for them include young shoots, leaves, and seeds [13].

Bamboo shoots, defined as immature culms growing from the nodes of bamboo pseudo-rhizomes, are esteemed as a highly desired vegetable with a sweet flavor, crisp texture, and remarkable nutritional potential [52]. They may be ingested fresh or subjected to various processing techniques, including fermenting, roasting, boiling, blanching, canning, and pickling. Bamboo shoots are reportedly consumed as fermented slices, crushed fermented damp shoots, crushed fermented dry shoots, fermented entire shoots, roasted whole shoots, and boiled whole shoots, among other forms [13]. Furthermore, bamboo leaves can be transformed into bamboo leaf tea [53]. Starch can be extracted from bamboo culms and seeds [54].

5.1. Fresh Bamboo Shoots

In China, India, and Southeast Asian countries, the culinary heritage of bamboo shoots has been a part of their food cultures for centuries. The use of bamboo shoots in various dishes is a testament to the rich and diverse cultures of the regions. People have created different culinary arts and processing techniques for using shoots from local species as food [55,56]. During cooking, bamboo shoots absorb the flavors of the ingredients and seasonings, which enhances their umami savoriness.

After the rainy season ends, bamboo shoots typically emerge and are harvested when they reach a height of 20–30 cm. Exposure to light leads to the formation of cyanogenic glycosides in bamboo shoots, resulting in a bitter taste [57]. Another observation was that, if not collected immediately after emerging from the earth, the shoot will become harder, piquant, or bitter. Young shoots from both running and clump-forming bamboos are consumable [22]. Species or varieties of bamboo with bitter-tasting shoots are often fermented or dried, whereas those with sweet tastes are consumed as fresh [58]. Bambusa polymorpha produces quality edible shoots with a distinct sweet taste in the raw form [59]. The level of antinutrients in bamboo shoots limits their food uses. The most predominant antinutrient in bamboo shoots is cyanogenic glycosides, which also cause bitterness. Using appropriate processing techniques, such as sufficient soaking and boiling, the level of antinutrients can be reduced to the barest minimum or eliminated [50].

Bamboo shoots have been used in Asian cuisines for ages, and the nutritional value is comparable to those of many commercial vegetables [24]. The common recipes include soups, stir-fries, or braised shoots with meat. Generally, fresh bamboo shoots are prepared by removing the sheath and boiling in water (whole or cut) to reduce bitterness and antinutrients before consumption or when used for cooking.

In Thailand and Lao PDR, freshly harvested bamboo shoots are famous for their use in making spicy soups. The shoots are finely grated and then boiled with the bamboo grass (T. triandra) broth and other ingredients. The leaves of bamboo grass are used to make the broth, primarily as a thickening agent [60]. Grated and/or sliced bamboo shoots in various sizes are usually boiled and then used as the ingredients for many dishes, such as stir-fried bamboo shoots, spicy salad, red curry soup, coconut cream soup, etc. For side dishes, whole peeled bamboo shoots are usually boiled and then used as vegetable side dishes.

In China, bamboo varieties without bitterness are used for cooking [61]. The authentic Chinese recipes from bamboos include braised bamboo shoots (with soy sauce and/or pork) and stir-fried bamboo shoots with mushrooms and/or pork [62].

Bamboo shoots have been integral to Indian cuisine for ages, especially in the northeastern states, such as Assam, Arunachal Pradesh, Manipur, Mizoram, Nagaland, and Tripura [63]. Bamboo shoots are incorporated as a taste enhancement in several dishes featuring tomatoes and lady’s fingers. In Indian cuisine, the shoots are typically sautéed or fried in oil and consumed as vegetables or incorporated with pork and other vegetables [56]. Prominent meals prepared with fresh bamboo shoots include the Manipuri cuisine Usoi-Ooti (a stew of peas and bamboo shoots), the Mizoram dish Rawtui-bai (bamboo shoot stew), and the Tripura dish Mia-gudhog (bamboo shoot curry) [64].

Bamboo shoots are not common for Western cuisines; however, some recipes, especially fusion recipes, use bamboo shoots as an ingredient. In Australia and New Zealand, fresh bamboo shoots are sliced into strips and boiled in lightly salted water before consumption [24].

5.2. Dried Products

As fresh bamboo has a high moisture content (70–90%), it therefore requires preservation to make it ready for further processing, storage, transportation, and utilization. Drying is one of the most common and oldest preservation methods being used. Dried bamboo food products that are commonly available commercially are dried bamboo shoots and dried bamboo leaves [20]. Dried bamboo can be ground and sold as dried powder. In addition, the dried leaves can be used for making bamboo leaf tea.

Although typical air oven drying may oxidize and degrade heat-sensitive polyphenols and change the nutritional content, flavor, and texture of the food, it is currently the usual procedure for drying bamboo [65]. On the other hand, adequate quantities of bamboo can be dried quickly using a variety of modern drying techniques, such as microwaves and freeze drying techniques [66,67].

Since no fuel is needed for the typical drying method, it is both simple and inexpensive. Nevertheless, climatic and meteorological factors have a significant impact on the process itself [68]. Another drawback of the open sun drying process is the enormous amount of open space that is needed to spread out the products while they dry. As they dry, the items are subjected to a wide range of environmental contaminants, including dust, rain, insects, and animals. To get around the problems with open solar drying, numerous designs for modern solar dryers have emerged, which resemble boxes with clear covers [69]. The outcomes vary depending on the drying technique.

In terms of sun drying, bamboo shoots are first chopped or sliced and then equally distributed on plates or clean cloths and dried under direct sunlight until the moisture content reaches below 10% [70]. Sun drying was protracted by the diminishment of the moisture content of shoots due to inconsistent drying and unpredictable weather conditions, which may also lead to the spoiling of bamboo shoots. The color of the shoots altered markedly, and the texture became rather rigid [71].

For tray and hot air drying, these techniques are efficient, as they can reduce the moisture content of fresh bamboo shoots to well below 10% within 6–10 h [65]. Upon rehydration, the firmness of the shoots decreases, but the color is similar to the fresh ones. However, hot air drying at high temperatures can cause intense browning, low rehydration capacity, and a loss of nutritive content in shoots [72].

Drying causes a reduction in nutrients in bamboo shoots, like protein (ranging from 3.51 to 33.38%), fat (ranging from 47.59 to 70.56%), fiber (ranging from 1.32 to 6.76%), and vitamin C (ranging from 6.34 to 29.76%) during drying [67]. Freeze drying methods were found to exhibit a lower loss in nutrients and antioxidant activity compared to high heat treatments like the oven, tray, and sun drying methods [67,73].

The employment of osmotic dehydration as a pretreatment can reduce total drying time. The osmotically dehydrated bamboo shoot was assessed using tray, fluidized bed, and vacuum drying methods. The combination of osmotic and vacuum drying methods provided better product quality in terms of rehydration ratio, color, and texture [74].

In terms of bamboo leaves, it has also been found that microwave, oven, and freeze-drying techniques retain superior phytochemicals compared to the conventional methods of sun and shade drying. Among those, freeze drying provided the best results [75]. Although an expensive and energy-intensive technology, freeze drying produced better-quality products in terms of preserving the antioxidant potential.

5.3. Pickled Products

One of the most often used preservation techniques is pickling; it improves the flavor and taste of food while also extending its shelf life. Bamboo shoot pickles are quite popular in some countries, e.g., India and Malaysia [76]. Bamboo pickles are made from tender shoots by cutting them into small pieces, then boiling and air-drying them for an hour before mixing with appropriate salts and spices, depending on the recipes. The shoots are then transferred to a sterile glass container, and hot mustard oil is poured over them before putting on the lid and keeping it unopened for a week [13]. High salt concentration is normally used for pickled products. It has been reported that bamboo pickles were produced by cutting them into the shape of a sheet; the shoots were then blanched by boiling water, placed in large plastic containers, brined with up to 20% salt, filled into an earthen jar, sealed with plastic rope, and stored under room temperature [77].

Typically, the pickling of bamboo entails a fermentation phase wherein natural microbial fermentation transpires during the preservation of the pickled bamboo shoots [77]. In Thailand, bamboo shoots are meticulously sliced and preserved in containers filled with water that has been washed from rice, with or without the addition of salt. This method differentiates bamboo shoots from the standard brine typically linked with other pickled items [78]. Fermentation occurs at ambient temperatures for no less than three days. The product’s acidity imparts an acidic flavor, with pH values between 4 and 5.5. A recent study revealed that Thai-style pickled bamboo shoots (Naw-mai-dong) may serve as a source of lactic acid bacteria (LAB) [79]. Bamboo shoots are abundant in cellulose and hemicellulose. Xylan constitutes a principal element of hemicellulose; microorganisms involved in bamboo shoot fermentation must possess the capability to effectively degrade and utilize xylan and its oligomers (XOSs) via their xylanolytic enzyme production capacity [80]. Due to the acidity of the finished pickled bamboo shoots, acid-tolerant bacteria may be utilized as probiotics. Furthermore, pickled bamboo shoots may preferentially create conditions conducive to the selective enrichment of XOS-fermenting probiotic LAB [79].

The qualities of the bamboo shoot products that are ultimately produced are impacted by the pickling process. The pickling process causes the amino acids found in bamboo shoots to be converted or decomposed into other compounds, which ultimately results in a reduction in the amount of amino acids present. This drop is greatest for aspartic acid, followed by alanine and glutamic acids in a decreasing order. The process of pickling bamboo shoots causes the texture to become more pliable, which results in a decrease in the shoots’ hardness. Additionally, the protopectin content of bamboo shoots decreases, which therefore has an effect on the alterations that occur in the microstructure of the bamboo shoots that have been pickled [77].

5.4. Fermented Products

A number of Asian countries consume fermented bamboo shoots. There are many traditional fermented shoots that are popular, including Naw-mai-dong (Thailand), Suansun (China), Tama (Nepal), and Jiang-sung (Tai-wan) [81]. Manipur, Meghalaya, Mizoram, and Sikkim are some of the northeastern Indian states where bamboo shoot fermentation has been common practice for a long time [2]. The action of microorganisms during fermentation facilitates the formation of flavor, aroma, and texture in the finished products. Additionally, they are acidic and easily digestible [20]. Although there are some regional and cultural differences in the specific steps of the fermentation processes, the basic concept of bamboo shoot fermentation is universal [82].

There are four distinct methods based on the shape of the products that are used for fermentation. These include whole, sliced, wet crushed and fermented, and dried crushed and fermented shapes [81]. In India, Arunachal Pradesh and Manipur are two Indian states that produce the famous fermented whole shoots [63]. It takes more time for this fermented shoot to fully ferment than the others. Following harvesting and cleaning, the shoots are subjected to fermentation under anaerobic conditions. This is conducted by using heavy weights and the right kind of packing. Fermented sliced shoots are the most common type of fermented bamboo shoots used in most nations. Newly harvested bamboo stalks are washed, and their hard sheaths are removed; subsequently, they are thinly sliced. For a few months, they are pressed down and kept under pressure, where they are allowed to ferment. Fermented bamboo shoot exhibits a long shelf life after fermentation is finished. In Indian cuisine, it is typically consumed after being prepared with other vegetables, fish, and meat [81]. In Thailand, Naw-mai-dong is a pickling fermentation product that can be used as a fermented vegetable in a variety of Thai recipes [78].

The two methods of crushing and fermenting bamboo shoots are wet and dry fermentation. Both begin with cleaning and preparing the shoots by crushing them using a mortar and pestle. Then, they are placed in plastic or glass containers of varying sizes or polythene bags. The fermentation process takes around two to three months to complete; then, the crushed and fermented wet product is ready to be served. The crushed and fermented dry product can be made by fermenting bamboo shoots in sealed containers for just three to seven days before exposing them to sun drying. Once they have dried sufficiently, they are placed in polythene bags for future use [81].

The fermentation process imparts a unique aroma and flavors as a result of the specific active compounds formed during fermentation. The flavor is typically sour. The most significant aroma-active components present in fermented bamboo shoots are acetic acid, (E,Z)-2,6-nonadienal, methional, p-cresol, 2-heptanol, linalool, and phenyl acetaldehyde [83]. The most prevalent of these is p-Cresol, which is bio-transformed from tyrosine, a significant free amino acid in bamboo shoots, and imparts a barn-like odor to bamboo [84].

The fermentation bacteria were mostly identified as Lactobacilli, Pediococci, Leuconostocs, and Enterococcus. Through the characterization of phenotypic properties and molecular techniques, specific strains of lactic acid bacteria were identified in conventionally fermented shoots, including L. brevis, L. curvatus, L. plantarum, P. pentosaceus, Leuc. mesenteroides, Leuc. fallax, Leuc. lactis, Leuc. citreum, and E. durans [85]. Different bacterial strains were identified and isolated from fermented bamboo shoots in different forms and places [86,87]. Diverse isolated individuals exhibited variability in their activity. L. brevis showed the greatest capacity for phytic acid degradation, while L. xylosus exhibited the highest levels of protease and lipolytic activity. L. plantarum was the predominant species identified in the fermentation products, exhibiting the highest cell hydrophobicity. The majority of the lactic acid bacteria exhibited potential probiotic and antagonistic properties against specific pathogenic bacteria [79,81,86].

In terms of the nutritional value of fermented vegetables, they will initially lose water and vitamin C. For bamboo shoots, soluble protein content increased during fermentation (an increase from 3.1% to 7.8%) due to the proteolytic metabolic activities of the microorganisms, which make fermented bamboo a good source of digestible proteins. Regarding fat content, the lipid content in bamboo stalks decreases [2]. Fermentation alters the dietary fiber content of fermented bamboo shoots by causing pectin disintegration in the cell wall and depolymerization under non-enzymatic action [88]; consequently, the texture of fermented vegetables will change [89]. Fermentation decreases the cyanogen in bamboo shoots; the cyanogenic glycosides content was reduced to be within the limit (<10 ppm) in the most traditionally fermented bamboo shoot products [90].

5.5. Thermally Processed Products

The high moisture content of bamboo shoots makes them easily perishable, giving space for the growth of undesirable microorganisms like bacteria, molds, and yeasts. Thermal processing is one of the most commonly used processing methods for the preservation of bamboo shoots. Canning has been proved to be effective in abating rancidity and preventing microorganism growth in bamboo shoots [57,91]. For the production process, a sterilization temperature level is required as bamboo shoots are classified in a low-acid vegetable category. Fresh bamboo shoots are cut from the head and tail. After chopping, slicing, and grading, the bamboo shoots are boiled, drained, and canned. Brine solutions are added to the cans, which are exhausted and sealed. Sterilization is processed through a retort at a temperature of 121 °C [92]. Bamboo shoots have been found to be cooked or canned with Yanang juice, instead of a brine solution. Yanang is a species of flowering plant native to mainland Southeast Asia, particularly Thailand and Lao PDR. It was found that heating bamboo shoots in Yanang juice resulted in greater reduction in uric acid than heating in water [92]. Recently, soft packaging, such as retort pouches, is gaining popularity due to its convenience and because it is environmentally friendly. Research has demonstrated that substituting aluminum cans with retort pouches in the production of ready-to-eat food can significantly reduce environmental effects in all impact categories [93]. Canned bamboo shoots can be adequately preserved and used in a variety of foods, including vegetables and pickle sauces [94].

5.6. Bamboo Leaf Tea

For many years, bamboo leaf tea has been considered a delicious and healthy drink in Asian countries. The general production involves cleaning and cutting young bamboo leaves into small pieces, then roasting them in an open pan at low heat until the leaves become soft. The roasted leaves are then ground into fine particles and sealed in tea bags [95]. Detailed production steps may differ depending on countries and regions. The bamboo leaf tea may be mixed with green tea or other herbals to produce herbal infusions [31]. A number of additional herbal infusions, each with its own unique flavor profile and set of health advantages, have recently gained popularity. A variety of herbal teas, including yerba mate, hibiscus, cinnamon, chamomile, kudzu, bamboo leaf, kombucha, spice, and yerba, have a long history of usage as traditional remedies [96]. The traditional Uyghur medicine known as zhucha is made from green tea and bamboo leaves, which have anti-inflammatory and fat-burning properties [97].

In recent years, bamboo leaf tea has gained popularity in numerous Western countries [53]. It is favored for its skin moisturizing and body chilling properties, and its production is anticipated to reach 20,000 tons in China by 2022 [19]. Extensive research has been conducted on bamboo leaf infusions to investigate their immune-stimulating, anticarcinogenic, antidiabetic, antiulcer, anti-inflammatory, and anti-helminthic properties [98,99,100,101]. Bamboo leaves contain a variety of bioactive compounds that function as exceptional bio-antioxidants [102]. The primary antioxidant components of bamboo leaf extract are phenols and their derivatives, phenolic acids, flavonoid and flavone glycosides, polysaccharides, phytosterols, and terpenoids [103,104]. A promising capacity to reduce blood lead levels in rodents by up to 64.3% has been demonstrated by antioxidants from bamboo leaves [105]. Consequently, they have been advised for use in a variety of pharmaceutical applications [31]. Bamboo leaves are abundant in protein, calcium, iron, and magnesium, and they are free of caffeine and theine. They can be employed as food additives, flavoring agents, and preservatives in a wide range of food products. Additionally, they have been employed in the biological fortification of various food products to improve their shelf life and flavor, reduce harmful acrylamide produced during processing, and enhance their nutritional value [3,100].

5.7. Dietary Fiber from Bamboo

Bamboo fiber is a cellulosic fiber that is regenerated from bamboo plants. For textile fiber, it is produced through alkaline hydrolysis and multiphase bleaching of bamboo culms and leaves followed by chemical treatment of the starchy pulp generated during the process [106]. For dietary fiber, it is mostly produced from bamboo shoots.

Bamboo shoot fiber is the most recognized bamboo product within the food business. Commercial edible bamboo fibers are available in the market, especially in Asian countries, including Jelucel^®BF, Nutriloid^® Bamboo Fiber, and CreaFibe [9]. Furthermore, these fibers are well received in the international market and have been utilized in the formulation of bread [107], quick noodles [108], pasta [109], biscuits [110], sausages [39], and yogurt [111]. Bamboo fiber is extensively utilized as a fiber source for gluten-free goods [112].

Bamboo shoots mostly include dietary fibers, particularly insoluble dietary fibers, such as lignin, cellulose, and hemicellulose. The sheath and basal bamboo shoots have significantly higher polysaccharide content values, leading to a crude fiber content ranging from 8.2 to 37.1 g/100 g on a dry basis in the entire bamboo shoot [113]. As the bamboo shoots become older or go through processing steps like fermentation and canning, their fiber content rises [114]. Previously discarded as industrial by-products, these polysaccharides are now seen as a valuable source of prebiotic fiber [113]. A broad range of nano-, micro-, and milli-scale materials have been produced utilizing bamboo cellulose fiber, and the production of bamboo fiber has recently attracted interest [115].

Extraction conditions play a major role in the obtaining of dietary fiber with desirable or undesirable nutritional and physicochemical properties. The extractions involve various solvents to eliminate other non-dietary fiber substances, i.e., carbohydrates, proteins and lipids. Each method has the main purpose of purifying dietary fiber and eliminating different substances, thus affecting the quality of the dietary fiber obtained [116].

Fibers can be extracted from a variety of sources using chemical extraction techniques, the most common of which is the alkali extraction method. The degradation of the food matrix as a result of the processing conditions of time and temperature is, however, the primary drawback of alkaline extraction [117]. Loss of soluble dietary fiber, hemicelluloses, and cellulose could occur as a result of the hydroxyl ions breaking ester links and disrupting hydrogen bonds [118]. Although it is time-consuming and expensive, enzymatic extraction manages to circumvent some of the issues that plague alkaline extraction, including high pH, corrosion, and a substantial amount of waste. Enzymatic extraction produced the highest grade of fiber according to its physicochemical qualities when tested with water, citric acid, ethanol, acids and bases, and other solutions [119].

New techniques for aided extraction, including shear homogeneity, microwave, and ultrasonic techniques, have recently attracted a lot of interest. Technologies like shear homogeneous-aided enzymatic extraction [120] and ultrasonic-assisted enzymatic extraction [118] are examples of new forms of assisted extraction that have been studied. Shear homogeneous-assisted enzymatic extraction has many benefits over other conventional procedures, such as low-stress operation, easy scaling, and good yields [121].

Dietary fiber derived from bamboo shoots is a cost-effective substitute for fiber obtained from other sources. Their applications in food processing are on the rise due to their extensive biological activities [122]. A recent study demonstrated that bamboo dietary fiber could prevent obesity and enhance lipid profiles in rodents that were fed a high-fat diet by regulating the gut microbiota [123]. However, the high concentration of insoluble dietary fiber exhibits fewer health benefits when compared to the soluble dietary fiber, and this limited its industrial applications. Consequently, it necessitates additional modifications to enhance its technological capabilities for use in the food industry [39]. Consequently, it necessitates additional modifications to enhance its technological capabilities for use in the food industry [124].

Physical, chemical, enzymatic, and emergent new techniques can be employed to implement modifications. In particular, biological fermentation and chemical modification methods have been employed to enhance the soluble fiber content of dietary fiber extracted from bamboo. However, the control of fermentation conditions is challenging, and chemical methods with restricted reaction conditions result in low soluble fiber conversion efficiency and the introduction of harmful chemical groups [125]. It has been well established that the thermal and chemical modification methods enhance the specific physicochemical and functional properties of soluble fiber by reducing particle size, rather than by increasing the soluble fiber content [126]. Extrusion treatment is a widely used method of physical modification for fiber-rich products, which has the potential to enhance the nutritional quality, flavor, texture, and appearance of food [127]. Other physical modifications, such as high-temperature heating, high-pressure homogenization, and ultrasonic treatment, have been identified as effective in enhancing the physicochemical and functional properties of bamboo shoot dietary fiber [128]. Nevertheless, it has been demonstrated that enzymolysis can increase the amount of soluble fiber [124]. The bioactivity of dietary fiber is likely to be influenced by the increased exposure of functional groups, which is a result of the hydrolysis of cellulose and hemicellulose components by cellulase [129]. New technologies are emerging for the modification of dietary fibers in bamboo shoots, including extrusion–cellulase treatment [130], enzymatic hydrolysis, and dynamic high-pressure microfluidization [124]. There is still a need for novel methods that yield superior outcomes. Bamboo fiber can be utilized to fortify a variety of food products, including biscuits, pastries, and meat products, thereby improving their functional properties [91].

5.8. Starch from Bamboo

Starch can be isolated from bamboo culms [131] and seeds [54]. However, the young bamboo culm has a higher content of starch, which is more easily extracted when compared to bamboo seed starch [27]. The chemical method employing sodium metabisulphite solution (200 ppm at 5 °C for 60 s) was commonly used for bamboo starch isolation [27,132,133]. The starch was then separated by sieving and centrifugation.

Bamboo seeds (P. heterocycla var. pubescens (Mazel) Ohwi) were subject to starch isolation, and it consisted of 68.2% starch on a dry basis. The bamboo seed starch also possessed compound granules with morphology and diameters that were comparable to those of rice starch. It exhibited a higher pasting temperature but a substantially lower viscosity than the rice starches. This could be attributed to the amylopectin’s smaller molecular weight and gyration radius, as well as its higher amylose content [54].

The starch isolated from young bamboo culms of B. tuldoides exhibited properties akin to cereal starches and bamboo seeds, including complex granules, A-type polymorphism, and elevated transition temperatures, with no notable differences seen among the starches isolated from various parts of the young culm. It also exhibited a tiny diameter and a propensity for retrogradation, which was attributable to the levels of amylose and ether extract, as well as the short chains of amylopectin (DP 6–12) [132]. However, another report found that the starch from the young bamboo culm of B. vulgaris (about 17% yield) exhibited different characteristics depending on the position of extraction in the culm; for example, the starches extracted from the bottom and middle presented higher amylose content, which is characteristic of resistant starch type 2, and high relative crystallinity, compared to the top [133].

The starches possess potential for industrial applications as an alternative to traditionally utilized starches, particularly under conditions of elevated temperatures and/or mechanical agitation. Furthermore, the incorporation of starch will facilitate the utilization of the fiber from the young culm of bamboo, a co-product option for bamboo fiber extraction, thereby promoting the comprehensive utilization of bamboos [27,133].

5.9. Bamboo Juice

This sap juice comes from the fresh stems of moso bamboo (P. edulis), pink and green bamboo (P. glauca), and other types of bamboo [134]. People in China drink bamboo juice, which is called “zhuli”, as a natural medicine and drink. Also, bamboo juice oral solutions (BJOL) are widely used in China to treat cough and phlegm and can be found in almost all pharmacies [135]. In China, many oral liquids made from bamboo juice are sold as herbal treatments in the form of a decoction.

Bamboo juice is rich in phenols, amino acids, inorganic elements, and organic acids [136]. Amino acids and guaiacol were reported to be the main components in bamboo juice [137]. While it is still not clear which active ingredients of bamboo juice are successful at treating cough and phlegm, oral liquids made from bamboo juice that are sold in China are thought to help with coughing [138]. In Chinese hospitals, BJOL is often given as a natural, traditional plant medicine to people with coughs and asthma, especially kids and women who are pregnant.

5.10. Sugars from Bamboo

The cellulose, hemicellulose, and lignin that make up bamboo cell walls can be converted to sugars. Prior to hydrolysis, a single pretreatment or a mixture of pretreatments has been used as the first step in converting bamboo. Certain factors, such as the hydrolysis technique and process conditions (enzymes, surfactant additions, chemicals, and structure of pretreatment bamboo), may help achieve the sugar yield in the hydrolysis process [139]. It has recently been discovered that xylo-oligosaccharides (XOS), a type of functional oligosaccharide made up of 2–10 D-xylose molecules joined by β-1,4-glycosidic linkages, may have health benefits via enhancing gut health [140]. In general, lignocellulosic biomass, which includes bamboo, wood, and agricultural waste, is the main source of XOS [141]. To obtain XOS, the hemicellulose component must be hydrolyzed using either chemical techniques (mild acid hydrolysis and hydrothermal pretreatment) or specific enzymes (endo-xylanase or β-xylosidase). Bamboo shoots provide the most advantageous substrate for the manufacture of XOS among lignocellulosic biomasses due to their elevated carbohydrate content and diminished lignin concentration [142,143].

5.11. Bamboo Related Foods

Omphisa fuscidentalis, commonly known as the bamboo worm, is a widely consumed edible bug in the Indochina Peninsula [144]. This insect is frequently found in Myanmar, Loa, and northern Thailand. In addition to being a favorite food of mountain tribes, the mature larvae have recently gained popularity in cities. With the exception of July through September, when there are no larvae in the field, they are offered in marketplaces practically all year round. Young bamboo shoots are the main feeding source for bamboo borer larvae [145]. Mature larvae are usually deep-fried and seasoned with soy sauce for consumption in Thailand. According to an analysis, the dry basis content of deep-fried O. fuscidentalis was 3.9% ash, 26.70% protein, 55.80% fat, and 11.50% carbohydrate [146]. There have also been recent reports of similar nutritional components [147].

In Korea, bamboo salts are primarily consumed for health reasons due to the fact that they are produced using processes that result in a reduction in toxicity and the conversion of acidity to strong alkalinity when compared to sun-dried salts. The typical method of producing bamboo salts is as follows: the products are inserted into bamboo and covered with yellow mud. They are subsequently baked in a kiln at approximately 1000 to 1500 °C for 8–10 h with pine wood and pine resin, and subsequently powdered. They are repeatedly inserted into the bamboo and baked. Ultimately, they are baked at a temperature of approximately 1300 to 2000 °C [148].

Purple bamboo salt is produced in Korea by a traditional method that involves conventional salt and bamboo. In comparison to crude salt, purple bamboo salt exhibits elevated levels of iron, silicon, potassium, and phosphate, although its sulfate concentration is diminished [149]. Purple bamboo salt is recognized for its diverse medicinal effects on ailments [150].

Bamboo beer is famous in China. Several factories in China are producing bamboo beer from Moso bamboo (P. heterocycla var. pubescens or P. edulis) juice [20]. The fine bamboo leaf juice is produced by concentrating the extract of the green desiccated bamboo leaves in a vacuum dryer. The liquid is added to the original beer, which is then mixed, filtered, and bottled to create the bamboo beer. The beer that results is abundant in flavonoids [28].

Bamboo wine can be made from the sap of bamboo shoots or from bamboo leaves [91], while bamboo wine is the result of the fermentation of shoot liquid. Bamboo wine, which is typically an alcoholic extract or a combination of fermented leaf extract and starchy nutritional components, is derived from bamboo leaves. These two wine varieties are abundant in water-soluble B vitamins, essential and nonessential amino acids, and a variety of antioxidants [151].

6. Cooking Utensils from Bamboo

The non-toxic and long-lasting qualities of bamboo culms have made them useful as cooking implements. The Bidayuh have long relied on bamboo for its strength and versatility, which they put to use by making polished cooking containers and implements like spoons, spatulas, and ladles. One of the earliest known ways of cooking may have involved using bamboo stalks as utensils [152].

In traditional Southeast Asian countries and some parts of China, glutinous rice is put into bamboo culms and cooked using an open fire [153]. It can have different names depending on the country, such as Lemang (Indonesian) [154] and Khao-larm (Thai) [155]. Glutinous rice, which is used as the main ingredient, is washed thoroughly and rinsed by clean water and then mixed with coconut milk and salt before cooking using an open fire. It serves as a traditional food for some religious festivals [156]. Meat, fish, and chicken can be cooked using bamboo culms as well in Southeast Asian cuisines [152].

7. Bamboo as Animal Feeds

As mentioned earlier, there are two species, giant panda and golden lemur, which feed almost exclusively on various parts of the bamboo [13]. Research has been conducted on the use of bamboo leaves as fodder for several animal species, including cattle, sheep and goats, in many Asian and African countries [40,157]. Bamboo shoot shell has been reported to exhibit a high potential nutritional value and the inclusion in an ammoniated rice straw diet improved the growth rate of ruminants and the feed conversion rate [158]. More research is needed for the applications of bamboo residues as feed.

8. Conclusions and Prospects

Bamboo has shown that it has the potential to become a future food source that can meet the needs of both sustainability and nutrition. As a consequence of this, there has been a substantial amount of interest from both the scientific community and the business sector in speeding up their use and implementation. There is a need to extend the use of bamboo in food, particularly in the development of novel food items that use the edible portions of bamboo. Although various countries offer a variety of goods that are based on bamboo, there is still further need to increase the use of bamboo in food.

In order to increase the production of functional foods made from bamboo and to encourage the use of bamboo-based components, the food industry must overcome several obstacles. There are still certain difficulties related to the exploitation of bamboo edible components, such as the presence of antinutrient toxicity and the absence of standardized methods for harvesting and preserving the bamboo. It is possible that the exploitation of bamboo shoots or the establishment of standardized processing procedures could be hampered by the differences in characteristics and nutritional values that exist among the various species of bamboo. Standards or quality requirements for edible bamboo components endorsed by international organizations or associations may assist in the promotion of bamboo usage. The development of industrial food processing techniques that guarantee the quality and safety of bamboo could play a significant role in expanding the use of edible bamboo products. There is still a need for research and development in the processing of bamboo components on an industrial scale. Overcoming those challenges is essential for achieving effective industrial development of shoot-based products and innovative functional foods.