Effect of different organic growing conditions on quality of cooked potatoes

Abstract

In 1997 and 1998 the effect of six different organic treatments on the chemical, rheological and sensory quality of cooked potatoes was investigated. Cattle slurry and cattle deep litter were each applied to sandy soil in three ways. The type of manure applied gave the most distinct effect on sensory quality. Manuring with slurry decreased dry matter, starch and phytic acid and increased N and rheological properties (modulus of deformability, stress, strain) signi®cantly compared with deep litter manuring. Maturity of tubers was assumed to be the main cause of these differences. Regarding the sensory quality of potatoes, minor differences were found among the organic treatments investigated. Potatoes manured with slurry were slightly moister and seemed to have higher discolouration and off-odour and lower yellowness than potatoes manured with deep litter. Mealiness was highest when composted deep litter was ploughed in and lowest when deep litter and straw were ploughed in. The observed differences in sensory quality are presumably an effect of availability of N in the manure. Chlorogenic acid was the only phenolic acid that was affected by the organic treatments. The variation in phenolic acid and scopoletin contents did not seem to in¯uence the off-taste of potatoes. As the sensory quality of potatoes produced by different organic treatments had not been addressed previously, this study revealed interesting results.

Role of cultivation conditions in potato sloughing as indicated by CPEM method

“…A similar relationship was observed by Hegney and McPharlin (2000) where the level of disintegration was assessed on a standard five-point scale. Our results were in qualitative agreement with data obtained by Searle et al (2005) and by Thybo et al (2002). The lower degree of sloughing for fertilised tubers could be explained by the nitrogen application and concentration, which might reduce starch content and potato tuber density (O'Beirne and Grouping according to the cultivation factors see Table 1.…”

“…Thybo et al (2002) observed a significant effect of organic treatments with variation in available N on texture presented by stress and strain in uniaxial compression. Results obtained by Searle et al (2005) indicate that culinary quality of potatoes can be influenced by crop management.…”

Suitability of Organic Potatoes for Industrial Processing: Effect of Agronomical Measures on Selected Quality Parameters at Harvest and after Storage

“…In previous studies, increased N supply by means of mineral (O'Beirne and Cassidy 1990) or organic (Thybo et al 2001) N fertilization decreased the DM concentration of tubers which was assumed to be a result of postponing maturation (Hope et al 1960). The marked decrease in tuber DM concentration after cattle manure in 2004 and after combined K (potassium sulphate) and N (horn grits) fertilization in both seasons (Table 6a) may be explained by the appreciable tuber fresh yield response in that season (Haase et al 2007a), i.e.…”

“…Organic cultivation of potato raw stock for industrial processing of French fries or crisps may be a new source of income for organic farmers (Kuhnert et al 2004), yet research until recently exclusively focused on table potatoes (Thybo et al 2001;Neuhoff and Köpke 2002;Wszelaki et al 2005). The quality standards for processing potatoes differ markedly from those for table potatoes.…”

Texture analysis of raw and cooked tubers of short‐duration lines of cassava by multivariate and fractional conversion techniques

“…it is a dimension reduction technique that maps the variation and correlation among many variables into lower dimensions. 49 The number of PCs was chosen based on the eigenvalues and also by comparing the % explained variance along the PC axes and the average contribution for each variable as described by Piggot 50 and Etievant et al 51 In the case of cooked cassava tubers the first six PCs had eigenvalues greater than unity and the % explained variance along these six axes was greater than the average contribution of each (data not shown). The first six PCs explained about 92% of the total variation.…”