Effect of vacuum cooking treatment on physicochemical and structural characteristics of purple‐flesh potato

Abstract

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 The cooking treatments could combine pairing conditions of time and temperature, therefore an adequate 50 experimental design is imperative to provide proper conclusion. Response Surface Methodology (RSM) is a useful 51 experimental design to explore relationships between several variables and one or more responses (Myers et al. 2002, 52 Montgomery et al. 2010. In food engineering is used to reduce the cost of experimentation, by reducing the number 53 of experiments needed for modelling a process. It has been used in a wide range of applications, for instance to 54 optimize conditions of anthocyanin extraction from purple sweet potato, the potato dehydration and for the freezing 55 with pressure steaming of potato tissues (Fan et al. 2008, Mudahar et al. 2007, Alvarez et al. 1999. To the knowledge 56 of the authors, no study reports the changes of texture, colour and anthocyanin of cooked purple-flesh potato applying 57 CV and SV treatments. 58 59The aim of the present work is to study the textural, colorimetric and nutritional changes in purple-flesh cooked potato 60 applying two vacuum treatments (cook-vide and sous-vide) using RSM. Moreover, the comparison of Cryo-SEM 61 micrographs tries to achieve a better understanding of changes in mechanical properties evaluated instrumentally. 62 MATERIALS AND METHODS COOKING METHODS 68Two vacuum treatments were used in the study: cook-vide (CV) and sous-vide (SV). For the CV, the cooker device, 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 Table 1). A five-coded level; two-factor central composite design (orthogonal and rotatable) was employed 73 (Myers et al. 2002, Kuehl 2000. After cooking, samples were vacuum-sealed (98% vacuum) in heat-resistant 74 polyethylene pouches (Cryovac® HT3050) using a vacuum packaging machine Technotrip, Terrassa, Spain) and 75 stored under refrigeration conditions (3-4 °C) until analysis. 76 77For the SV treatments, raw potato cylinders were vacuum-sealed (98% vacuum) in heat-resistant polyethylene pouches 78 (Cryovac® HT3050) using a vacuum packaging machine (EV-25, Technotrip, Terrassa, Spain). The cylinders were spread 79 in the pouch to avoid overlapping. The cooking treatment was conducted in a water bath at atmospheric pressure (GD 80 120, Grant Instruments, Cambridge, UK). The temperature conditions ranged from 78 to 92 °C. The cooking times 81 varied from 16 to 44 min using the same RSM design of CV (Table 1). 82 83All samples were stored at 3-4 °C for 24 h before the instrumental measurements to simulate the conditions in the 84 catering industry as applies the sous-vide to minimize the workload during services. 85 INSTRU...

Influence of Selected Factors on Anthocyanin Stability in Colored Potato Extracts

“…This effect leads to loss of anthocyanin color, since the aglycone forms are more stable than their glycosidic forms. In this sense, both anthocyanin losses and color reduction have been reported by Iborra‐Bernad et al () and Hoon‐Moon et al . () in potato samples subjected to temperatures from 60 to 92C.…”

“…This effect leads to loss of anthocyanin color, since the aglycone forms are more stable than their glycosidic forms. In this sense, both anthocyanin losses and color reduction have been reported by Iborra-Bernad et al (2015) and Hoon-Moon et al (2015) in potato samples subjected to temperatures from 60 to 92C. It has also been reported that light accelerates the degradation of anthocyanins (Markakis 1982), particularly when fluorescent light is combined with slightly elevated storage temperatures (Palamidis and Markakis 1978).…”

Physico‐Chemical and Structural Characteristics of Vegetables Cooked Under Sous‐Vide, Cook‐Vide, and Conventional Boiling

“…The knowledge of how each type of cooking treatment can affect each vegetable could be interesting to increase the quality of the ready‐to‐eat products. Therefore, studies applying different cooking treatments on the same product (Chiavaro and others ; Iborra‐Bernad and others ; Lachman and others ) are relevant to select the right culinary factors and increase the nutritional and sensorial quality offered to consumers.…”

Evaluating and correlating the mechanical, nutritional, and structural properties of carrots after multiple freezing/thawing processing

“…And the processed tissues could become more deformable producing a softer and rubbery texture (Loredo et al 2014). Similarly, after vacuum-boiled treatments potato tissues become lower hardness and cohesiveness because of the cell turgidity loss (Iborra-Bernad et al 2014). Besides, cell wall components (especially cellulose) possess the function of maintaining the rigidity and resistance of tissues.…”