Encapsulación del aceite de oliva virgen extra para la mejora de la calidad, la vida útil y el proceso de elaboración de alimentos empanados

Abstract

The current profile of the food consumer is characterized by the search for a balance between convenience and nutrition and health. Thus, today's consumers want foods that fit into their busy lifestyles. They look for foods that are easily available and ready to eat. However, as awareness increases about how food impacts our health and quality of life, the demand for more nutritious, balanced foods with health-beneficial properties grows. As part of their health-conscious lifestyle, many consumers avoid fatty foods or their alternatives that do not meet the typical sensory expectations of these products as the process technology changes. In the meat industry, one of the reasons why breaded products are underrated is their high fat content. This Doctoral Thesis aims to provide the market with a healthy and sensorially similar alternative to conventional breaded meat foods, thus increasing the number of options on the market and dealing with these conflicting preferences adapted to the lifestyles of today's consumer. This objective was sought to be achieved by carrying out the following series of specific objectives shown below. The replacement of the main operation that causes the increase in fat in these foods (pre-frying by immersion in boiling oil), with the incorporation of microencapsulated extra virgin olive oil (EVOO) in the food matrix (in the batter or breading), in combination with another precooking heat treatment other than immersion frying, which has been called new technology (NT) in this work. To this end, the process of microencapsulation of EVOO in different encapsulation matrices (sodium alginate, alpha-cyclodextrin (αCD), gamma- cyclodextrin (γCD), and maltodextrin (M)) was also developed, as well as the study of its characteristics, and the process of releasing EVOO in the consumer's mouth, in contact with saliva, at the time of consumption. Once the best EVOO microencapsulation formula and technology was found, the influence of the addition of microencapsulated EVOO on the microbiological, physicochemical and sensory quality of different breaded meat products was evaluated. Subsequently, different types of alternative thermal treatments for pre-cooking and final cooking were evaluated: hot air frying, forced convection hot air baking and medium and short wavelength infrared baking, to organoleptically achieve the best combination of microencapsulated EVOO application and cooking. The results of this Doctoral Thesis have demonstrated the effectiveness of EVOO microencapsulation in both cyclodextrins studied, αCD and γCD, in proportions of 1.0:3.4 and 1.8:4.6 (host:guest, p:p ), respectively, αCD being economically and nutritionally more adequate, as it is considered dietary fiber. The microencapsulated EVOO introduced in the batter or glue did not obtain satisfactory results on an organoleptic level. It was revealed that the microencapsulated EVOO, when incorporated into an aqueous solution, is not available to achieve adequate sensations of the EVOO in the mouth, as the EVOO is released from the internal cavity of the cyclodextrin, is lost during the process and/or moves towards the interior of the product and not towards the breading. On the contrary, when the microencapsulated EVOO was added to the breadcrumbs, not only were adequate EVOO sensations achieved in the mouth, but the breadcrumbs used could also be distinguished on the palate level in comparison to the products fried in oil. The gradual release of EVOO in the mouth was demonstrated using an artificial saliva model, which allows the flavor and aroma of the oil to be perceived constantly during the tasting of the product. Regarding alternative heat treatments, it was concluded that the hot air and forced convection baking method proved to be inadequate to achieve the desirable sensory characteristics of breaded meat products, as it did not obtain an appearance (color) similar to that of breaded products, current pre-fried foods on the market. Infrared cooking appears as a promising alternative. The results revealed that shortwave infrared cooking was more suitable for products that require less deep heat penetration, given that very high surface temperatures are achieved for short periods; while cooking by medium wave infrared, in combination with the use of EVOO microencapsulated in breadcrumbs, proved to be more efficient in imitating the color and texture characteristics of a pre-fried product. However, these similarities varied depending on the chromatic values and granulometry of the breadcrumb mixtures used. Regarding the shelf life of breaded products, it was observed that NT notably reduced microbial growth in breaded products, increasing the shelf life of the breaded product to which it was applied by 2 to 5 times. It was also demonstrated that the sole use of microencapsulated EVOO in breadcrumbs significantly reduced the proliferation of spoilage microorganisms. This effect was associated with oleic acid and phenolic compounds present in EVOO. NT led to a reduction in fat content from 50 to 80% compared to the fat content of fried breaded products, while fiber content increased from 12 to 50%. Unfortunately, the results indicated that the level of acrylamide in the precooking process was not benefited since no significant differences were found in the levels of this compound. Likewise, significant sensory differences were shown between the conventional production of breaded products (control) and the NT. In this way, this Doctoral Thesis demonstrates that, in general, products breaded with NT constitute new products that would have high market acceptance by consumers, perhaps similar or greater than traditional breaded products.