Comparison of physical, microstructural and antioxidative properties of pumpkin cubes cooked by conventional, vacuum cooking and sous vide methods

Abstract

BACKGROUND Current dietary guidelines recommend five or more fruit, vegetable, and legume servings per day. Often, these products are eaten cooked, resulting in organoleptic and nutritional changes. Vacuum cooking is gaining attention as an alternative cooking technique, due to its ability to preserve or even enhance sensory and healthy properties of food. Its household application is, however, poorly explored. In this work, the effect of vacuum cooking, performed with a new patented system, was studied for the first time on pumpkin cubes and compared to sous vide and traditional steam cooking, through a multidisciplinary approach. RESULTS All the cooking treatments damaged pumpkin microstructure, leading to cell separation and plasmolysis; vacuum cooking was the most aggressive method, as confirmed by texture softening. Vacuum cooking was also the method with less impact on pumpkin color, in relation to the largest extraction of some classes of carotenoids from the broken cells. Significant polyphenol extraction, especially of gallic acid and naringenin, was instead observed for sous vide and steamed pumpkins. The total antioxidant activity, ascribable to the effect of both carotenoids and polyphenols, resulted enhanced after cooking compared to raw one mainly for cook vide samples, followed by steamed and sous vide ones. CONCLUSIONS Vacuum cooking, followed by sous vide, has often shown better performance than traditional steam cooking for pumpkin cubes. The implementation of sous vide and vacuum cooking at domestic level or in professional kitchens, and in the food industry, would allow the consumption of vegetables with improved nutritional and sensorial characteristics. © 2020 Society of Chemical Industry

Comparative study of the effects of thermal blanching pretreatments and puffing temperature levels on the microstructure and qualities of crisp banana slices

“…The pretreatment bananas were distinguished by lose cell-to-cell connections between them and a corresponding increase of intercellular space. The loss of cells adhesion in the cells matrix due to thermal blanching pretreatments suggests the destruction of chemical bonds between pectin polymer chains, that is, ionic bridge and Hbound (Chang et al, 1993), resulting in a middle lamellar that is depolymerized and subsequently loses its ability to bind cells (Greve et al, 1994;Rinaldi et al, 2021). Similar findings were observed in blanched carrots (Wang et al, 2021) and blanched potatoes (Roy et al, 2001).…”

“…These cell wall characteristics are difficult to observe under a transmission electron microscope (TEM), compared with the cell wall of nonthermal blanching samples (Ahmed, Mirza, & Arreola, 1991;Roy, Taylor, & Kramer, 2001). In addition, thermal pretreatments can also cause the disintegration of the middle lamellar layer due to depolymerization of pectin chains that are contained inside it (Chang, Tsai, & Chang, 1993;Rinaldi et al, 2021). Previous studies reported that hot water or steam pretreatments decreased considerably the firmness texture and induced gelatinization of starch granules; vapor diffusion is then limited by the gelatinized layer during puffing step, which drives a larger volume expansion in the puffed starchy food (Varnalis, Brennan, & MacDougall, 2001).…”

Unveiling the Bioactive Potential of Fresh Fruit and Vegetable Waste in Human Health from a Consumer Perspective

“…Vacuum cooking is gaining popularity due to its ability to preserve or even enhance the sensory and health properties of different foods. Using pumpkin cubes as a model food, Rinaldi, et al [71] showed that vacuum cooking was more aggressive than sous vide or steaming, resulting in faster and deeper texture softening, but simultaneously less impact on pumpkin color despite the greatest extraction of some classes of carotenoids from the broken cells. In contrast, significant polyphenol extraction, especially of gallic acid and naringenin, was more efficient with sous vide and steaming pumpkins [71].…”

“…Using pumpkin cubes as a model food, Rinaldi, et al [71] showed that vacuum cooking was more aggressive than sous vide or steaming, resulting in faster and deeper texture softening, but simultaneously less impact on pumpkin color despite the greatest extraction of some classes of carotenoids from the broken cells. In contrast, significant polyphenol extraction, especially of gallic acid and naringenin, was more efficient with sous vide and steaming pumpkins [71]. On this point, it is important to note that cooking can be used to add bioactive compounds to foods.…”

Effect of vacuum application on the physical, rheological and sensory characteristics of an artisanal ice cream

“…2013; Rinaldi et al . 2021). These findings led to the development of different equipment such as the Gastrovac® (International Cooking Concepts, Barcelona, Spain) already tested in previous research (Iborra‐Bernad et al .…”