Murniece I.,Latvia University of Agriculture |
Karklina D.,Latvia University of Agriculture |
Galoburda R.,Latvia University of Agriculture |
Santare D.,Food Center |
And 2 more authors.
Journal of Food Composition and Analysis | Year: 2011
The information about nutritional composition of potatoes at both the ingredient and recipe levels in the Food Composition Data Base (FCDB) of Latvia is insufficient. Therefore, the aim of this research was to determine the nutritional composition and energy content of potatoes prepared by traditional cooking methods before and after storage. Five Latvian potato varieties were selected: Lenora, Brasla, Imanta, Zile and Madara. A two-year research was conducted during two periods: just after harvesting (2007, 2008) and after six months of storage (2008, 2009). The following cooking methods were used: shallow frying (150 ± 5°C); deep-fat frying (180 ± 5°C) and roasting (210 ± 5°C). The weight of the potatoes was recorded before and after frying along with the time and temperature during frying. Chemical analyses were performed to determine the content of reducing sugars, starch, fructose, glucose, sucrose, fibre, fat, protein, moisture, vitamin C and amino acids. The content of the analyzed nutrients differed significantly between both potato varieties and applied cooking methods: differences between potato varieties and cooking methods were found for vitamin C, moisture, reducing sugars, fructose, glucose, sucrose, amino acids, essential amino acids, and energy content, whereas significant differences in starch, fibre, fat and protein content were found between cooking methods. © 2010 Elsevier Inc.
Dias M.G.,Instituto Nacional Of Saude Doutor Ricardo Jorge Insa Ip |
Camoes M.F.G.F.C.,University of Lisbon |
Oliveira L.,Instituto Nacional Of Saude Doutor Ricardo Jorge Insa Ip
Food Chemistry | Year: 2014
The effects of freezing and storage temperature on the mass fraction of α- and β-carotene, β-cryptoxanthin, lutein, lycopene and zeaxanthin in minimally processed fresh food products, were evaluated after sample preparation, extraction and saponification (only when strictly necessary). Effects of freezing and long-term stability were studied at two temperatures, -20 and -70 C, using high performance liquid chromatography (reversed phase columns, UV-Vis diode array detector) at time points during storage; measurement uncertainty was included in the evaluation. Stability of working standard solutions was also examined. Freezing did not affect the carotenoid mass fraction under the conditions studied. Carotenoids in orange, cherry, peach, apple, and kale were stable (except α-carotene and zeaxanthin in peach) for 13, 9.7, 5.7, 2.5 and 7.5 months, respectively. For these food sample matrices, no significant difference between the freezing/storage at -20 and -70 C was observed. Standard solutions (0.05-5 μg/mL) were stable for at least 6 months at -70 C, except lycopene which at 0.05 μg/mL was apparently stable only for six weeks. © 2014 Elsevier Ltd. All rights reserved.