22 January 2024
Eben van Tonder

Pomo is a delicacy in Nigeria and is widely consumed. It is essentially the skin of a cow that has been processed for consumption, often used in various stews, soups, and appetizers. The preparation involves burning the cow skin to remove the hair, and then it’s further processed and softened by boiling.

Pomo is a regular feature in Nigerian cuisine and is often enjoyed at parties and events, served in different formats. There is a belief among the food safety authorities that pomo is not a nutritionally rich food. It is rich in collagen and fat and its value in nutrition should not be minimised.

Collagen, particularly from beef skins, is therefore a significant protein source in various food formulations, including those used in Nigeria. It is true that collagen is not a complete protein as it lacks certain essential amino acids. Its value in its high collagen content alone makes it important as a food source.

Let’s first look at the value of pomo as part of a balanced diet and then we will delve into the composition of collagen, its importance, and how supplementing with texturized vegetable protein (TVP) from soy can create a more nutritionally complete product.

Pomo as part of a Balanced Diet

Collagen, especially from sources like beef skins (pomo), plays a significant role in the diet, offering unique benefits for both the elderly and the young. While it’s true that collagen is not a complete protein – lacking in some essential amino acids – its presence in a balanced diet is extremely valuable.

Benefits of Collagen for the Elderly:

1. Joint Health: Collagen is a key component in joint cartilage. Supplementation or dietary intake can help reduce joint pain and degeneration, which is particularly beneficial for those suffering from conditions like osteoarthritis.
2. Skin Elasticity: As we age, our body’s collagen production decreases, leading to wrinkling and sagging skin. Dietary collagen can help improve skin hydration and elasticity.
3. Bone Health: Collagen provides structure to bones. Its intake can help in maintaining bone density, reducing the risk of bone-related conditions like osteoporosis.

Benefits for Young People:

1. Growth and Repair: Collagen is crucial for the growth and repair of tissues, particularly during periods of rapid development in children and adolescents.
2. Skin Health: For young people, a diet rich in collagen can promote healthier, more resilient skin.
3. Muscle Maintenance: Collagen contains amino acids like glycine and proline, which are important for muscle growth and repair.

Collagen as Part of a Balanced Diet:

• In Nigeria, pomo is often included in meals not as the sole source of nutrition but as part of a more diverse diet. This means that the limitations of collagen as a protein source are balanced by other protein-rich foods that provide the essential amino acids.
• The value of pomo, through its collagen content, is enhanced when combined with other nutritious foods like grains, vegetables, and other protein sources. This leads to a well-rounded diet.
• It’s also important to note that collagen’s role in nutrition extends beyond its protein content. It has unique amino acids that are not as abundant in muscle meats.

Major Constituents of Collagen

1. Glycine: The most abundant amino acid in collagen. Glycine is crucial for the synthesis of creatine, which provides energy to muscle cells, and it’s also important for the synthesis of glutathione, a potent antioxidant.
2. Proline and Hydroxyproline: These amino acids are important for the stability of the collagen helix. They play a vital role in joint health and skin elasticity.
3. Alanine and Arginine: These are also found in significant amounts in collagen. Arginine is important for immune function and wound healing.

Importance to the Human Body

The major part of beef skins (pomo) is collagen and fat. Let’s now delve into the value of collagen to understand its role in human nutrition.

• Joint and Bone Health: Collagen supports joint health by helping to maintain the integrity of cartilage, which is essential for robust joint function.
• Skin Health: Its role in skin elasticity and hydration is crucial, making it beneficial for skin health.
• Muscle Repair and Energy Production: Glycine and proline aid in muscle repair. Glycine also contributes to energy production in cells.

Collagen and Complete Nutrition

We said that collagen is not a complete protein. A complete protein is a type of protein that contains all nine essential amino acids in sufficient amounts necessary for the dietary needs of humans. Essential amino acids are those that the body cannot synthesize on its own and must be obtained from food. These amino acids are vital for various bodily functions, including building and repairing tissues, synthesizing hormones and enzymes, and supporting immune function.

Amino acids are organic compounds that combine to form proteins, which are crucial for many bodily functions. They are often referred to as the building blocks of proteins. Twenty different amino acids can form a protein, and each one has a unique structure and specific role in the body. While the human body can produce some amino acids, the essential ones must be obtained through diet. Foods that contain all nine essential amino acids, like meat, dairy products, and quinoa, are considered complete proteins, while those lacking one or more essential amino acids, like many plant-based proteins, are called incomplete proteins.

While collagen is rich in some amino acids, it lacks others like tryptophan. This deficiency is overcome by the rest of the food consumed by a person in a day. When we consider a single food source, a novel approach will be to include pomo in a sausage and add an ingredient containing tryptophan such as soy. This is where texturized soy protein becomes valuable. Soy protein is a complete protein, meaning it contains all essential amino acids required by humans.

Adding Texturized Soy Protein to Collagen-Based Sausage

The benefit of such a formulation will be twofold.

• In Terms of Providing a Complete Amino Acid Profile: TVP complements the amino acids missing in collagen, creating a more balanced protein source.
• In Terms of Its Overall Nutritional Value: TVP is not only high in protein but also contains fibre, vitamins, and minerals, enhancing the nutritional profile of the sausage.

Digestibility of Collagen from Beef Skins

Collagen derived from beef skins is generally well-digested and absorbed by humans. This makes it a viable source of certain amino acids and peptides that can have beneficial effects on joint, bone, and skin health.

Fat from Beef Skins

The other major constituent of beef skin, besides collagen, is fat.

• When processing skin and separating collagen and fat, the type of fat obtained is primarily saturated and monounsaturated fats.
• Monounsaturated Fats, are generally liquid at room temperature and are abundant in plant-based oils like olive oil, canola oil, and peanut oil, as well as in avocados and nuts. These fats are considered heart-healthy because they can help reduce bad LDL cholesterol levels while maintaining good HDL (high-density lipoprotein) cholesterol levels. They are a staple of the Mediterranean diet, which is widely recognized for its benefits in reducing the risk of heart disease and promoting overall health.
• Nutritional Aspect: The fat from pork and beef skins can contribute to the energy content of the food.
• Health Perspective: While saturated fats are essential in moderation, excessive consumption may be linked to higher cholesterol levels and heart disease risk. Therefore, balancing the fat content with healthier fats (like polyunsaturated fats) in the diet is important.

It is important in this context to consider Saturated Fats in greater detail. Saturated fats are typically solid at room temperature and are found in animal products like meat and dairy, as well as some plant-based sources such as coconut oil and palm oil. Historically, saturated fats have been linked to increased cardiovascular disease risk, primarily due to their effect on raising LDL cholesterol levels. However, recent research suggests a more nuanced view.

Recent meta-analyses and observational studies have shown inconsistencies in the relationship between saturated fat intake and heart disease. Some studies found no significant association between saturated fat consumption and heart disease, while others indicate that the impact may vary based on the type of saturated fats and the overall dietary context. For instance, it’s been observed that not all saturated fats uniformly raise levels of small, dense LDL particles, which are more strongly related to cardiovascular disease risk. Instead, they tend to raise larger LDL particles, which are less associated with cardiovascular disease.

Furthermore, foods rich in saturated fats like whole-fat dairy, unprocessed meat, and dark chocolate, which also contain a complex matrix of nutrients, have not been consistently linked to an increased risk of cardiovascular disease. This suggests that the health effects of foods cannot be predicted solely based on their saturated fat content, and the overall macronutrient distribution and food matrix must be considered.

Application in Nigerian Formulations

Incorporating collagen and fat beef skins in Nigerian sausage formulations can enhance the texture, flavour, and nutritional content. Beef collagen and fat could be more widely acceptable and utilized.

Using collagen from pork and beef skins, supplemented with texturized soy protein, can create a nutritionally rich and balanced food product. While collagen provides major health benefits, its lack of essential amino acids is well compensated for by the inclusion of soy protein. However, the type and amount of fat in these formulations should be considered to maintain a healthy nutritional profile. Pomo itself should not be considered on its own since nobody consumes only pomo and nothing else. It is always part of a diet and never the sole component for an entire day and weeks on end. Evaluating it therefore in isolation is silly and the benefits from a nutritional standpoint are many with overwhelming evidence of its benefits to the human body! The sausage option with TVP supercharges this already impressive food source!