Wheat Kernel: How to Preserve Better Quality

Wheat kernel is among the most crucial cereal crops grown across the world and forms a substantial part of the diet of a large segment of the worldwide population. The wheat kernel, or wheat berry, is the seed from which the wheat plant sprouts, and it is also the part of the plant that is harvested and made into food products. This document examines the structure, composition, functions, and the kernel of wheat in detail.

The wheat kernel has three major parts:

• Bran
• Endosperm
• Germ

This is the outer covering of the wheat kernel, which weighs approximately 14.5% of the kernel’s total weight. It is also the bulk of dietary fiber, minerals, and antioxidants. The bran has many other layers such as;

• A nucellar tissue’s modified form, the hyaline membrane, is a semi-transparent layer that manifests from the tissue.
• Nucellar tissue is a plant component of an ovule that supplies the embryo with nutrients during its growth phase.
• Certain seeds possess modified remnants of the nucellar tissues that provide covering and storage for the seed.

• Seed Coat is the Testa, the boundary of the seed that acts as a protective shell for the embryo shielding it against biological harm, dehydration, or infections.
• Tube Cells are the type of cells present in flowering plant pollen grains that give rise to the pollen tube and have an important role during fertilization. This may not directly concern the seed coat but is vital in the reproductive process of flowering plants that lead to seed development.

• The epidermis is the thin outermost layer of cells in the seed, leaf or even fruit of a plant.
• Epidermis of emerging seeds and fruit pericarps may gain specialized appendages called cuticles or trichomes.
• In fruits and seeds, to cater for environmental impediments, the epidermis acts as a physical barrier and limits pathogen attack as well as dehydration.
• In an apple, the epicarp is represented by the fruit’s skin. The epicarp is the outermost layer of the pericarp, also known as the fruit wall. To make it difficult for external elements to damage the fruit, the skin is often hard or waxy. 

• The endocarp is a crucial part/functions as the innermost zone of the pericarp which protects the seed. In the case of drupes such as peaches, the endocarp becomes hardened and gourd shaped, encasing the seed within.
• Cross cells are a form of cross shaped parenchyma, being elongated and found commonly in the seed coat or pericarp. These are for the seed coat’s structural support.

• The hairs of brushes are extensions fashioned like hair that can be found in seeds and in other plants such as barley and wheat.
• Such structures help with wind or fauna seed dispersion. This may also help with moisture and germination.
• They’re all associated with the structure of the seed and the early stages of growth for the plant, especially in monocots such as maize, rice and wheat. Here’s what each of them means:

Bran is used largely in the production of whole wheat flour, and also refined bran is produced from cereals but is not added to flour grains as in whole wheat flour.

 While the roots and leaves have not developed it supplies the embryonic plant with food during the first period of growth. It contains 83% endosperm of wheat kernel. The endosperm is comprised of mainly starch with some protein. It contains:

• Evaluating the intra seed structure, the endosperm forms the principal tissue responsible for the reserves needed by the embryo for development.
• The endosperm cells holds within them starch granules, which constitute the primary energy deposit ahead of germination.
• These starch granules are embedded within a protein matrix which aids in holding the seed structure while also contributing to the nutrition of the grains.

For instance, in wheat, this protein matrix is made up of gluten proteins (gliadin and glutenin) that have an effect on dough structure.

• The walls of all seed tissues such as the endosperm and aleurone are primarily composed of cellulose.
• Cellulose is a type of carbohydrates that has a complex structure, and provides the cells with rigidity and strength.
• Those walls work to protect the nutrients that are stored in the seeds, and ensure the seed’s durability and viability.

• It is the outermost layer of the endosperm that contains proteins and is located directly below the bran of cereal grains, as well as covering the starchy endosperm in wheat.
• It plays an important role in the process of germination by producing enzymes such as amylases and proteases that step nourishment and proteins in to serve as nutrition for a developing seedling.
• The aleurone layer of the grains is of importance nutrition as it contains a balanced starchy roughage with proteins, oils, vitamins, and even mineral constituents.

Germ comprises 2.5% of the wheat kernels total weight. It is the reproductive embryo of a wheat kernel. The germ is rich in essential vitamins, particularly B-complex and E, healthy fats, proteins and minerals. Flour’s shelf life is extended by removing the germ during milled refining, however its oils can go rancid overtime. 

• The rudimentary primary root which can also be referred to as radicle is the initial root that sprouts from the seed during the germination process.
• It expands to absorb water and nutrients while anchoring the seedling on the soil.
• In monocots, such as wheat and maize, the adventitious roots that stem from the stem replace the radicle, which is usually replaced.

• The young stem, also called the plumule, refers to the embryonic shoot of the plant.
• It is preceded by germination and consists of stems and leaves.
• In monocots, the sheath covering the plumule is protected by coleoptile during its emergence from the soil.

• Coleoptile with monocot seeds protects the plumule while aiding in its emergence from the ground.
• The coleoptile protects the young shoot from damage during its push through the soil.
• Upon sprouting, the coleoptile stops growing, and the first true leaves come out of it.

• The scutellum is specific in monocot seeds especially in grasses.
• It is a modified cotyledon (seed leaf) that supplies produced nutrients from the endosperm to the developing embryo.
• It is critical in the early stages of growth because it absorbs and directs stored food.

Wheat kernels are a rich source of nutrition containing multiple macronutrients and micronutrients in a balanced form. A common wheat kernel is comprised of: 

• Carbohydrates (60-70%): In the form of starch which is utilized as an energy source.
• Proteins (10-15%): It contains gluten which is beneficial for making baked foods.
• Fiber (10-15%): Primarily found in bran, it helps in digestion and maintains healthy intestines.
• Fats (2-3%): Partly unsaturated and located in the germ.
• Vitamins and Minerals: Incorporates B vitamins together with vitamin E, iron, magnesium, zinc selenium, and folate.

Various forms of wheat kernels possess different nutritional value, but generally speaking, per 100 grams of whole raw wheat, the ratio is as follows:

• Calories: ~340 kcal
• Carbs: ~72 g
• Dietary Fiber: ~12.2 g
• Sucrose: ~0.4 g
• Proteins: ~13.2 g
• Lipids: ~2.5 g
• Saturated: ~0.4 g
• Monounsaturated: ~0.3 g
• Polyunsaturated: ~1 g

• Vitamin B1 (Thiamine): ~0.5 mg (42% DV)
• Vitamin B2 (Riboflavin): ~0.2 mg (15% DV)
• Vitamin B3 (Niacin): ~6 mg (38% DV)
• Vitamin B5 (Pantothenic Acid): ~1 mg (20% DV)
• Vitamin B6: ~0.3 mg (25% DV)
• Folate (Vitamin B9): ~40 µg (10% DV)
• Vitamin E: ~1 mg (7% DV)
• Vitamin K: ~1.9 µg (2% DV)

• Iron: ~3.6 mg (20% DV)
• Magnesium: ~138 mg (35% DV)
• Phosphorus: ~288 mg (41% DV)
• Potassium: ~363 mg (10% DV)
• Zinc: ~2.8 mg (25% DV)
• Calcium: ~34 mg (3% DV)
• Sodium: ~2 mg (0% DV)
• Copper: ~0.5 mg (25% DV)
• Manganese: ~3.8 mg (190% DV)
• Selenium: ~70 µg (127% DV)
• Other Components:
• Gluten: Present (~75–80% of total protein)
• Phytates: Present (may limit some mineral metabolism)
• Antioxidants: Lutein, zeaxanthin and ferulic acid

Different types of wheat may produce wheat kernels of different types such as:

• Hard Wheat: Rich in gluten and proteins , it is used for making bread and pasta.
• Soft Wheat: It is lower in protein and is used in making cakes, biscuits, and pastries.
• Durum Wheat: High in both protein and gluten strength suitable for pasta.
• White Wheat: Wide range of taste, but used in whole wheat products where milder taste is disused.
• Red Wheat: Rich in tannins; thus darker and stronger in flavor.

Wheat nuts go through a number of processes after harvesting in order to come up with wheat products. The main steps are:

• Cleaning: Getting rid of unwanted materials like stones, dirt, and other seeds.
• Milling: Shredding wheat nuts into flour or into other products.
• Refining: Separating the bran and germ from the endosperm to get white flour.
• Fortification: Adding nutrients that may be lacking in the refined flour.

Storage and Distribution Maintaining the product so that it does not lose freshness and is fit for consumption.

Food processing has a variety of uses for wheat kernels, such as:

• Flour: Whole wheat flour is used for the production of bread, chapati, and other whole grain products. Refined flour is used for pastries, cakes, and pasta.
• Wheat Bran: Wheat Bran is popular in cereals, baked products, and livestock feeds.
• Wheat Germ: Wheat Germ is incorporated into health foods to increase their nutritional value.
• Cracked Wheat and Bulgur: These are used in salads, pilafs and soups.

The health benefits of consuming wheat kernels in its whole form are:

• Better Digestion: Constipation is relieved by the consumption of whole wheat kernels because the high fibers aid in gut movements.
• Heart Wellbeing: Consumption of whole wheat aids in maintaining a healthy body because of its low cholesterol, this also reduces chances of having cardiovascular diseases.
• Weight Control: Proteins and fiber keep one feeling full longer which helps manage weight.
• Blood Sugar Regulation: Whole wheat is useful for a diabetic person since it has a low glycemic index.
• Chronic Disease Reduction: Regular consumption of whole foods lowers the chances of obesity, some types of diabetes, and forms of cancer.

Even with its advantages, the consumption of wheat presents some challenges:

• Celiac Disease and Gluten Sensitivity: Some people are unable to digest gluten without experiencing digestive discomfort.
• Allergic Reactions: People with gluten-sensitivity have adverse reactions towards wheat.
• Pesticide Residues: The use of chemicals like pesticides in conventional wheat farming can raise issues regarding food safety.
• Processing Losses: The refinement of wheat to white flour results in the loss of vital nutrients.

To sustain wheat consumption globally, suitable farming practices must be adopted, including the following:

• Crop Rotation: Combating soil exhaustion and pest infestation.
• Organic Farming: Less dependency on chemical fertilizers and pesticides.
• Water Conservation: Optimal irrigation techniques enable water resource preservation.
• Genetic Improvement: Cultivation of more productive and disease resistant wheat varieties.

A wheat kernel or wheat berry serves as the raw material for flour and other wheat-based edible products. Like other plants, wheat has a seed, which is the kernel. A wheat berry consists of three primary components: the bran, endosperm, and germ. The bran, the thickest layer, is made up of minerals, vitamins, and fiber, which makes it useful for digestion. The germ, the innermost section of the kernel, serves as a nutrient dense portion as it contains healthy fats, proteins, and vitamins such as B and E. The thintiendosperm, which makes up most of the kernel, primarily serves as an energy source as it consists carbohydrates and proteins.

As a result of its composition, wheat kernels are the foundation of key foods like pasta, cereals, and bread. Whole wheat retains the three components, while refined flour only contains the endosperm. This starchy portion alone makes these products easier to digest, but lack in nutritional value. Because of the ease with which wheat can be cultivated, it is grown and consumed widely across the globe.

The phrases “wheat grain” and “wheat kernel” are often used synonymously, though they do have slight variations. Wheat Grain refers to the recessive husk of a wheat seed, including the outer covering, the hull, which is sometimes left attached during harvesting. It is vague in scope as it includes every aspect of the wheat seed, especially the coverings that are inedible and getting rid of is customary before processing the seed. Wheat grains grow in cluster at the head of wheat stalks, and are harvested before they are made into food products.

On the contrary, a wheat kernel is the edible part of a wheat grain that is left after the removal of the outer husk. It has three major parts; bran which is the outer layer rich in fiber, germ as the nutrient-rich inner part, and endosperm as a starchy mid part. The wheat kernel is the section that is milled into flour or used whole in foods such as wheat berries. Not all wheat grains are referred to as kernels but only those that are processed to remove the outer hull. Every wheat kernel is sourced from wheat grains. Hence, the main difference is unprocessed wheat grains have an outer husk which is absent in refined wheat kernels.

The meanings of both terms, grain and kernel, have some similarities but are quite different at the same time, most especially in the context of agriculture and food production. A grain refers to the whole seed of plants that are produced like wheat, rice, corn, or barley. The seed is composed of all natural parts inclusive of the outer covering that is sometimes known as the hull or husk. Grains constitute the basic raw material for a multitude of food products and these seeds are collected from plants. These grains can either be consumed in their unprocessed form or be made into oils, flours, and several other products.

Conversely, a kernel specifies solely the inner edible food portion of a grain after its outer husk is removed. It consists of three primary parts: bran (the fiber-rich outer layer), germ (the nutrient-rich core), and endosperm (the starchy energy source). Kernels are the remains of grains once these have been processed, such as the grinding of wheat grains into flour or the extraction of corn kernels for food production. All kernels originate from grains; however, not all grains are termed kernels. The definition of a grain is the unrefined seed as a whole while a kernel is the unrefined seed of that grain.

The kernel is defined as the portion of the grain which can be eaten. It combines three main parts which are the bran, the germ, and the endosperm. The kernel is a nutrient rich seed found in cereal crops of corn, rice and wheat that is useful for making flour or consuming whole as in wheat berries. Carbohydrates, proteins, healthy fats, vitamins and minerals are all found in the kernel which makes it vital part of one’s diet. The kernel may remain whole as in whole grains or be refined, where parts such as the bran and germ are removed to produce white flour or polished rice. Regardless, the method of processing determines the form in which the kernel appears.

The bran, also referred to as the outer layer, is solely the upper part of the kernel. This outer shell is rich in fiber and contains essential nutrients such as B vitamins, minerals, and antioxidants. Bran serves as a shield for the germ which is the edible part of the seed protecting it from environmental and pest damage. When whole grains undergo processing into refined products, the bran is typically the first portion to go, leading to low fiber and nutrient levels in the processed form. Despite this, bran is greatly admired for its health advantages and is used separately to boost the fiber content in cereals and other baked goods.

The portion of the wheat kernel that contains the highest amount of starch is the endosperm. It is primarily utilized as the basic energy source for the growing plant and makes up the largest portion of the kernel. The Endosperm is made up of carbohydrates and some proteins, although it is deficient in fibers and many nutrients found in the bran and germ. In milling, refined white flour is produced from endosperm devoid of the bran and germ. While it is very common in baked goods and a lot of processed foods, whole wheat products, unlike the refined counterpart, make use of all parts of the kernel.

A wheat kernel is categorized seed of the wheat plant. It is separated into three parts: the bran, germ, and endosperm. The bran is the outer layer filled with fiber, the germ is the core that is full of vitamins and good fats, and the endosperm is the starchy middle part that provides energy. Wheat kernels can be consumed in their whole form serves as berries, or marketed into other food products. The whole wheat maintains the three parts, which makes it an enriched source of fiber, protein, and essential nutrients.

Wheat flour, on the other hand, is in powdered form and is obtained after grinding wheat kernels. The form of flour is determined by how much of the kernel is kept after processing. Refined flour, also referred to as white flour, is made of the starchy endosperm, with the bran and germ being removed. This makes it have a finer texture, but less fiber and nutrients. Moreover, it is widely used in baking and prepared goods. Whole wheat flour is deemed as a better choice because of its increased fiber and vitamin content.