Beginning Of Storage Period Research Articles

Genotype-Specific Features of Cold-Induced Sweetening Process Regulation in Potato Varieties Nikulinsky, Symphony, Nevski

Increasing the shelf life of potato tubers demands their storage under low temperature. However, storage at low temperatures causes activation of cold-protective mechanism, so-called cold-induced sweetening (CIS). During this process, the starch is converted into reducing sugars such as glucose and fructose. Upon processing at high-temperature, these sugars react with free amino acids, resulting in brown, bitter-tasting products, which reduces the consumer value of potatoes. In this study, we performed expression analysis of genes associated with cold-induced sweetening in potato tubers: vacuolar invertase (Pain-1), sucrose-synthase (SUS4), invertase inhibitor (InvInh2). Potato varieties Nikulinsky, Symphony, Nevski were used. All three varieties were found to accumulate sugars at low temperatures, the maximum accumulation of reducing sugars being observed at 4°C. It was found that the expression pattern of genes associated with cold-induced sweetening differs depending on the variety and storage duration. The increased expression of vacuolar invertase and its inhibitor is more pronounced at the beginning of storage period while the increased expression of sucrose synthase is more pronounced after three months of storage. At early storage periods, high expression of invertase and low expression of inhibitor is observed in Dutch variety Symphony, and vice versa in Russian varieties Nikulinsky and Nevsky. The participation of the studied genes in the process of cold-induced sweetening is discussed.

Genotype-Specific Features of Cold-Induced Sweetening Process Regulation in Potato Varieties Nikulinsky, Symfonia, and Nevsky

In this study, we performed expression analysis of genes associated with cold-induced sweetening in potato tubers: vacuolar invertase (Pain-1), sucrose synthase (SUS4), and invertase inhibitor (InvInh2). Potato varieties Nikulinsky, Symfonia, and Nevsky were used. All three varieties were found to accumulate sugars at low temperatures; the maximum accumulation of reducing sugars was observed at 4°C. It was found that the expression pattern of genes associated with cold-induced sweetening differs depending on the variety and storage duration. The increased expression of vacuolar invertase and its inhibitor is more pronounced at the beginning of storage period, whereas the increased expression of sucrose synthase is more pronounced after 3 months of storage. At early storage periods, high expression of invertase and low expression of inhibitor is observed in the Dutch variety Symfonia, and vice versa in the Russian varieties Nikulinsky and Nevsky. The involvement of the studied genes in the process of cold-induced sweetening is discussed.

The Effects of Treatment with Ethylene-Producing Tablets on the Quality and Storability of Banana (Musa sp.)

This study was conducted to assess the effect of ethylene producing tablet (patent no.10-1574011) and treatment period on quality and storability of banana (AAA - Cavendish group) fruit imported into Korea from the Philippines. Three and five days of treatment periods, and different concentrations of ethylene tablet (50 ppmv, 100 ppmv) and control (standard ethylene gas treatment at a concentration of 100 ppmv) were used for the study. Slightly higher respiration rate was observed in banana fruits treated with 50 ppmv in both 3 and 5 days after treatments as compared to the control. Better storability was observed with banana fruits treated with 50 ppmv and 100 ppmv as compared to the control. All the treatments were shown a decrease in firmness as the storage days proceeded. The highest firmness was recorded from 50 ppmv on the initial day of storage while the lowest was recorded from 100 ppmv on 9 day storage. It was observed that banana fruits could be stored for up to 12 days without losing their color quality in all treatments except for the control. However, the quality of fruits at the control rapidly decreased (lost marketability) after 9 days of storage. Banana fruits treated with ethylene tablet with 100 ppmv for 5 days recorded the highest soluble solids content (SSC) at the beginning of storage period which was similar with the control. However, banana fruits treated with ethylene tablet with 100 ppmv for 3 days showed better storability than the control. On the other hand, ethylene tablet with 50 ppmv for 5 days of treatment has extended banana shelf life without affecting peel color, firmness and SSC content. Hence, these results indicate that banana fruits treated with ethylene tablet with 100 ppmv for 3 days or /and 50 ppmv for 5 days are an optimum for ripening of banana to be used for market and ultimate consumption.

TREATMENT OF SNAP BEAN PLANTS GROWN UNDER SANDY SOIL CONDITIONS WITH SOME NATURAL MATERIALS AND ITS RELATION TO GROWTH, YIELD AND POD QUALITY

Two field experiments were carried out during the fall seasons of 2012 and 2013 at the Agriculture Research Farm, El-Kassasien Hort. Res. Station, Ismalia Governorate, Egypt, and storage Lab., Hort. Dept., Fac. of Agric., Zagazig University, to study the effect of seed and soil inoculation (arbuscular mycorrhizal fungi, soil yeast) as well as foliar application with some natural materials (pigeon manure tea, compost tea, humic acid and effective microorganisms) on growth, photosynthetic pigments, yield and its components as well as chemical constituents of snap bean pods (Phaseolus vulgaris L.) cv. Paulista. It aimed also to study the effect of the abovementioned treatments on snap bean pods storability during cold storage at 7 oC and 90-95% RH in different periods, i.e., 7, 14,21 and 28 days. Results show that there were significant increases in vegetative growth characters, photosynthetic pigments, yield and it's components as well as some chemical constituents of pods as aresult of snap bean seeds inoculation with AMF plus application with soil yeast around root zone by using hand sprayer as compared to other treatments. Spraying snap bean plants with pigeon manure tea at 10g/L recorded maximum values of vegetative growth characters, photosynthetic pigments, yield and it's components as well as chemical constituents of pods followed by humic acid at 3cm3/L as compared to the control. The interaction treatment between dual inoculation with AMF and soil yeast and foliar spray with pigeon manure tea gave the highest values of vegetative growth characters, photosynthetic pigments, yield and it's components as well as chemical constituents of pods followed by the interaction treatment between dual inoculation with AMF and soil yeast and foliar spray with humic acid. Generally, quality parameters of snap bean pods during cold storage at 7 oC and 90-95 RH indicate that weight loss was increased, while dry matter, total carbohydrates and crude protein percentage in snap bean pods were decreased as the storage period prolonged up to 28 days from the beginning of storage period. Green pods obtained from plants treating by dual inoculation with AMF and soil yeast and sprayed with pigeon manure tea or humic acid and stored at 7 oC and 90-95 RH for 21 days was the best interaction treatment recorded the lowest values of weight loss and the best values of dry matter, total carbohydrates and crude protein percentage.

Quality Attributes of Soy-yoghurt During Storage Period

The utilization of soybean milk in manufacturing yoghurt in Sudan was investigated. Soybean milk was prepared from grinded soybean seeds. Four samples of soy yoghurt product were used, namely sample A) 100% soymilk (sample B) 1:1 soymilk: cow milk), sample C (2:1 soymilk: cow milk) and sample D (1:2 soymilk: cow milk). The prepared soy yoghurt samples were stored at refrigerator temperature (10±2 C) o followed by analyses at 0, 5, 10, 15 and 20 days intervals. The chemical compositions of soybean milk used were the total solids (13.15%), protein (7.64%), fat (2.75%), pH-value (6.70) and titratable acidity (0.20%).The type of milk significantly (p<0.05) affected the pH-value of the soy yoghurt. Sample A was the highest (4.50), sample D the lowest (3.30) while sample B and sample C were at an intermediate position (3.50 and 3.70 respectively). Storage period significantly (p<0.05) affected the pH-value of soy yoghurt, the highest value (4.30) was obtained at the beginning of the storage period, while the lowest value (3.00) at the end. The type of milk significantly (p<0.05) affected the titratable acidity of the soy yoghurt. Sample A was the lowest (1.12%), Sample D was the highest (2.50%), while samples B and C were in an intermediate position. Storage period significantly (p<0.05) affected the titratable acidity of soy yoghurt. The lowest titratable acidity (1.21%) was obtained at the beginning of storage period and the highest (2.60%) at the end. The type of milk significantly (p<0.05) affected the wheying off of the soy yoghurt. Sample A was the highest (2.70 ml), sample D was the lowest (1.70 ml), while samples B and C were at an intermediate position. Storage period significantly (p<0.05) affected the wheying off of soy yoghurt. The lowest wheying off (0.00 ml) was obtained at the beginning of storage period and the highest (4.00 ml) at the end. The chemical analyses of soy yoghurt samples at zero time processing, sample A) 100% soymilk (was the highest (31.20%) for total solids and protein content (16.70%),while sample D (1:2 soymilk: cow milk) was the lowest (15.70%) for total solids and protein content) 11.25). Sample B and C were at an intermediate position. Sample A was the lowest (2.20%) for fat content, sample D was the highest (3.25%),while samples Band C occupy an intermediate position. The sensory evaluation significantly (p<0.05) affected by The type of milk and storage period revealed that, the best score (p<0.05) in appearance (4.38), flavour (4.10), texture (4.22) and overall acceptability (4.28) in sample D(1:2 soymilk: cow milk), the worst was recorded by sample A (Soymilk 100%) for appearance (2.68), flavour (3.48), texture (3.36) and overall acceptability (3.44). The other samples were at an intermediate position. It was found that 10 days storage period at refrigerator temperature (10±2 C) was quite satisfactory o to attain good quality soy yoghurt.

Tolerância de maçã 'Gala' a baixas temperaturas durante o armazenamento

O presente trabalho foi desenvolvido com o objetivo de avaliar a tolerância de maçãs 'Gala' a temperaturas baixas, em diferentes períodos, durante o armazenamento. Os tratamentos avaliados foram as temperaturas de 0 (padrão); -0,8 e -1,6°C, durante quatro meses de armazenamento refrigerado (AR) e durante oito meses em atmosfera controlada (AC) a 1,0kPa de O2 + 2,0kPa de CO2; e de combinação dessas temperaturas por diferentes períodos de tempo no início ou no final do armazenamento. Observando os resultados, as temperaturas de 0 e 0,8°C proporcionaram melhor qualidade aos frutos em relação a -1,6°C, em AR. Em AC, a qualidade dos frutos foi superior em 0°C, em comparação com as temperaturas de 0,8 e -1,6°C. As temperaturas de -1,6°C, para o AR, e de -0,8 e -1,6°C, para AC, quando aplicadas no início do armazenamento, foram mais prejudiciais à qualidade dos frutos do que seu uso no período final de armazenamento, provocando, principalmente, degenerescência interna, dano externo e podridões.

THE EFFECTS OF USING ALTERNATIVE SWEETENERS TO SUCROSE ON ICE CREAM QUALITY

ABSTRACT In this study, seven different ice cream samples were produced using sucrose, high fructose corn syrup (HFCS), glucose syrup (GS), honey, sucrose + GS, sucrose + HFCS and sucrose + honey mixtures (1/1). The ice cream samples containing only sucrose were used as control. The acidity values of the samples with sucrose and GS were lower than those of the others. The viscosity value of the sample containing honey and stored for 15 days was the lowest. When honey together with sucrose (1/1) was added to the ice cream mixture, the viscosity increased. On the other hand, using honey increased the fat destabilization value. The overrun ratio of the sample with sucrose was the highest. The lowest melting ratio was determined in samples containing GS at the beginning of storage period. The melting ratios of the ice creams slightly increased during 15 days of the storage. The highest glucose and fructose amounts were observed in the samples made with honey. Panellists preferred the ice cream samples with sucrose + GS compared to control and the other samples.PRACTICAL APPLICATIONSDue to increasing consumer demands for low calorie foods, products made with alternative sweeteners have became more popular recently. Changing attitudes in sucrose consumption have heightened because of its causing effect to diabetes and obesity. Therefore there is a need for evaluating the alternative sweeteners. Although there were many studies about ice cream in the literature, there are few studies on using different sugars in ice cream production.

Sulfur-containing components of gamma-irradiated garlic bulbs

Sulfur-containing components associated with garlic flavors were investigated to determine the effect of γ-irradiation at 0.1 kGy on the quality of garlic bulbs ( Allium sativum L.) during storage at 3±1°C and 80±5% RH for 10 months. Irradiation treatment had no influence on the amount of total sulfur and thiosulfinate of stored garlic for 10 months, while the storage period brought about a significant reduction ( P<0.05) in the content of both components after the 6–8th month of storage compared with that at the beginning of storage period. The identity of irradiated alliin ( S-allyl- L-cysteine sulfoxide) at sprout-inhibition dose was confirmed according to thin-layer chromatography, i.r. and NMR spectroscopy data.

Säilytysaineiden käytöstä porkkanan varastoimisessa

Säilytysaineiden käytöstä porkkanan varastoimisessa