Oils and Fats: Basics
Today, we will delve into the realm of oils and fats, exploring their roles in various baking, pastry, and cookie preparations, and discussing key factors to consider when choosing them. Given the complexity of the subject, we will address it through multiple entries. This first entry will cover more general topics.
Oils or Fats
Let’s begin by clarifying the terminology commonly used. In general, we refer to fats in a liquid state at room temperature, such as olive, sunflower, soy, and rapeseed oils, as “oils.” On the other hand, when these products are in a semi-solid state at room temperature, we typically label them as “fats,” including butter, lard, margarine, palm oil, etc. From a nutritional standpoint, they fall under the category of lipids, which, along with proteins and carbohydrates, constitute the main components of food.
Lipids are composed of triglycerides, with each triglyceride being a compound formed by attaching three fatty acids to glycerol. If, for any reason, one of these fatty acids breaks off, we get a diglyceride, and if two separates, it results in a monoglyceride, well-known for its emulsifying function. Both mono- and diglycerides continue to be integral parts of lipids.
Perhaps the most crucial point to grasp is that each fatty acid has a melting point. Consequently, within a triglyceride, there are portions with different melting points. In the same oil or fat, varying amounts of fatty acids can coexist. This means that at a given temperature a solid part and a liquid part can coexist, hence the term “semi-solid.” This mixture of liquids and solids enables some fats to spread easily. Therefore, oils and fats do not have a fixed melting point like ice but rather a melting range. When assessing a fat’s characteristics in this regard, we often examine the solid fat curve, defining the percentage that is solid or liquid as the temperature changes. This aspect is crucial, influencing functionality when incorporating these ingredients into bread, cakes, puff pastries, or cookies.
Considerations
Animal or Vegetable
While we often refer to animal fats and vegetable oils, this is not always the case. Fats derived from animal sources, such as lard or butter, generally have higher melting points than vegetable oils. However, some vegetable fats, like palm oil, can have higher melting points. It’s also possible to obtain vegetable fats with higher melting points through physical or chemical treatments, such as hydrogenation.
In general, preference leans toward vegetable fats or oils, but it’s essential to understand why and in which cases this rule may not apply. Firstly, there is a group of consumers who avoid animal products for various reasons. This group is divided based on whether they avoid all animal-origin foods, only meat and fish, or aim to minimize such consumption, with some intermediate cases. We won’t delve into their motivations, but like anyone else, they have the right to decide their dietary preferences, and products with animal components are not their preferred choice.
Religious reasons must also be considered. Muslims are prohibited from consuming pork derivatives, and Jews have significant dietary restrictions, some related to animal products. For example, the Jewish community forbids the consumption of pork and the simultaneous consumption of meat and dairy, including butter or cream. Hence, depending on the target audience and the countries where these products will be marketed, these factors should be taken into account. In such cases, obtaining halal (for the Muslim market) and kosher (for the Jewish market) certifications would be advisable.
Lastly, and perhaps most importantly, animal fats often have poorer nutritional quality, a less favourable nutritional image, and a higher cost. Poor nutritional quality is linked to their higher content of saturated fatty acids and cholesterol. While it’s true that some vegetable fats share similar characteristics in terms of saturated fatty acid content, the perception of most consumers towards them is generally more positive.
However, most vegetable fats often lack something hard to replicate: the unique taste and aroma present in animal fats. Animal fats contain certain components that impart distinct flavours and aromas, absent in vegetable fats. Therefore, if these flavours are valued, it is common to resort to the use of animal fats. Cultural or traditional reasons also play a role. Even specific regulations protecting these products acknowledge this specificity. Nevertheless, it’s true that many of these products have vegetable fat-based variants, either within the protected designations or independently. If substituting animal fats with vegetable fats, it’s possible to incorporate flavours to mimic those of the original animal fats. They may also introduce other types of aromas or even no additional aroma.
Nutritional Aspects
Despite the historically negative perception of oils and fats, there seems to be a consensus nowadays to differentiate based on the type of fat or oil. Regarding nutrition, one must consider not only nutritional quality but also nutritional image or how consumers perceive it. In general, without going into too much detail, saturated fats (with a high percentage of saturated fatty acids) should be reduced, given their demonstrated association with cardiovascular diseases and blood cholesterol levels (both total and LDL cholesterol). In fact, the level of saturated fats is one of the factors negatively considered in Nutri-Score labeling. In some countries where there are warnings about certain nutrient contents on labels, such as Chile, high levels of saturated fats must also be indicated. No system considers high fat and oil content directly negative, but indirectly due to their high caloric content, more than double that of carbohydrates or proteins. Therefore, if aiming to reduce the caloric content of a food, one of the most effective tactics is reducing fat and oil content.
Some studies correlate the content of certain fatty acids, such as omega-3, with better nutritional quality or advantages against certain diseases, such as cardiovascular diseases. Therefore, oils or fats with a higher presence of these fatty acids can be chosen. However, it’s crucial to rely on evidence, communicate honestly, and, if such practices result in higher costs or a loss of organoleptic quality, effectively convey these advantages to consumers.
Concerning the nutritional quality of fats, the presence of trans fatty acids should also be considered. These fatty acids are more common in hydrogenated fats. Hydrogenation is a technique that saturates fatty acids (incorporating hydrogen to reduce the number of double and triple bonds along the chains). Fats obtained through hydrogenation have a higher melting point and a lower risk of rancidity. Due to the issues associated with trans fatty acid consumption, alternative methods have been implemented nowadays to modify vegetable oils. These methods increase the level of saturated fatty acids, elevate the melting point, and reduce the risk of rancidity. Thus, vegetable fats with properties similar to hydrogenated fats can be achieved but with lower trans fatty acid content.
Regardless of the nutritional quality of different oils and fats, their image is crucial. Some companies have substituted other oils with olive oil for this reason. In some cases, the percentage is minimal, barely affecting the organoleptic quality of the final product, but the increased cost may be offset by the improved image. In other cases, an unfair negative image reduces the use of certain oils. For instance, the use of rapeseed oil is uncommon in Spain due to issues in the 1980s. The consumption of rapeseed oil treated to prevent consumption by the population, which contained a toxic substance (aniline), resulted in hundreds of deaths and affected thousands of individuals. Despite approximately 40 years passing and rapeseed oil’s good quality compared to other oils and fats, a negative connotation of this oil still persists in Spain.
In recent years, an aggressive campaign against the use of palm oil has influenced its usage. This campaign has been based on both nutritional and environmental aspects. Some companies have chosen to maintain it in their formulations but address environmental concerns through certification. However, others have opted to replace it with different types of fats. In these cases, there is no certainty that the alternative is nutritionally better, but at least the name “palm” has been eliminated (some products even boast about it on the labeling), improving the overall image.
The nutritional quality of fats is a complex topic that requires careful study. This entry does not aim to delve deep into the subject but rather to highlight some aspects to consider. For a more in-depth understanding of the negative effects of trans fats or saturated fats, the positive effects of certain omega-3 fatty acids, or other aspects related to the nutritional quality of fats, referring to more specific literature is necessary.
Taste and Aroma
As mentioned earlier, some animal fats, like butter or lard, have a distinct taste and aroma cherished by certain consumers. Occasionally, these aromas are also tied to some traditional preparations. While some manufacturers of vegetable fats may introduce aromas to imitate those of these products, replicating the original is challenging. However, these strong flavours can be a drawback in other preparations traditionally known for milder flavours or for certain audiences.
Similar to animal fats, there are vegetable fats or oils with a very characteristic taste, suitable for some preparations but less ideal for others. An example is olive oil, which is often associated with savoury dishes rather than sweet ones. Therefore, apart from certain Mediterranean regions where olive oil has traditionally been used in the preparation of cakes (such as muffins) or cookies, its use in certain pastry products can be challenging in other areas. Nevertheless, this distinctive and characteristic note can be sought after in specific preparations.
Price and Legal Aspects
Although sometimes not explicitly mentioned due to its obviousness, legislative aspects and regulations in each country must always be considered. Similarly, certain geographical indications or quality designations require the use of specific fats or oils. Naturally, the price of each fat or oil is a highly influential factor when developing a product or attempting to reduce the cost of existing ones, either to lower the retail price or increase profit margins. It’s worth noting that some fats and oils have more volatile costs than others. In some cases, substituting one fat for another is relatively straightforward, especially when they don’t contribute very distinctive flavours and aromas.
Functionality of Fats
This is the most critical aspect when selecting a fat, as it influences various aspects of the final product, such as volume, shape, or texture. It also affects its suitability for different processes. However, as this entry would become excessively long, we will leave this point for a future post.