Bivalve molluscs, seafood, emerging technologies, digestibility, consumption.

Scallops “Nodipecten nodosus” (Linnaeus, 1758) are marine aquatic filter-feeding organisms, consumed raw or after cooking, with high thermal sensitivity and a short shelf life under refrigeration. The application of High Hydrostatic Pressure Processing (HPP) can promote the extension of the shelf life of foods through the inactivation of contaminating microorganisms and endogenous enzymes that cause spoilage. This Thesis is structured in one Geral Introdution, four Chapters and one General Concusion. Chapter I covers the review of scallops and the application of HPP in fish products. Chapter II comprises a consumer study using word association modulated by neophobia, on the consumption of seafood and specifically, scallops. In general, income, consumption habits and lack of knowledge about scallops influenced the frequency of consumption of the mollusk. The degree of food neophobia played an important role in participant perception and the associations generated by consumers of low and medium food neophobia for seafood were mainly related to positive hedonic characteristics. In Chapter III, the effect of the HPP on scallop adductor muscles was studied, using pressures of 200 to 400 MPa and process times of 2.5 and 5 minutes, on color, water activity, water retention capacity, microbiological and physicochemical characteristics of processed scallops, compared to fresh scallops. The effect of processing on texture was also evaluated, comparing the same process conditions on scallops subjected or not to previous cooking. Pressures of 200, 300 and 400 MPa for 2.5 or 5 minutes showed significant effects in reducing microbiological load, without relevant changes in physical-chemical characteristics, after cooking. HPP did not substantially alter the texture of the cooked scallops. In Chapter IV, the effects of treatments at 200 MPa/2.5 min and 400 MPa/5 min. were evaluated, compared to the in fresh scallop as control, on the structure, digestibility and in vitro bioaccessibility of adductor muscle protein, subjected to prior cooking.  HPP influenced protein digestibility, improving the bioaccessibility of crude protein, especially at higher pressure levels. Differential Scanning Calorimetry results indicated that higher pressures reduced the endothermic transition temperature, facilitating the denaturation of proteins. Although APH did not interfere with myosin unfolding, tyrosine concentration was affected by cooking. These results suggest that HPP can improve digestibility and reduce the negative impacts of heat, offering products with greater bioactivity and better nutritional performance. The results generally highlight the potential of HPP of scallops, promoting greater microbiological safety and preserving their nutritional qualities and instrumental texture characteristics, and possibly favoring consumer acceptance of the product.