• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.231-236
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• 2008

Response surface methodology (RSM) was used for the analysis and optimization of the production process of strawberry Kochujang. Experiments were carried out according to a central composite design, selecting strawberry puree content and red pepper powder content as independent variables and soluble solids content, moisture content, water activity, color characteristics ($L^*-$, $a^*-$, and $b^*$-values) as response variables. The polynomial models developed by RSM were highly effective for describing the relationships between the study factors and the responses. Kochujang containing a higher amount of red pepper powder had a higher soluble solids content; on the contrary, soluble solids content decreased with the increase in the strawberry puree content in the sample. Moisture content increased with increased strawberry puree content but decreased with increased red pepper powder content. Water activity increased with the increase in strawberry puree content in the sample but was less affected by the amount of red pepper powder content. Decreases in $L^*$-values with increasing amount of red pepper powder were noted. $a^*$-values decreased with the increases in red pepper powder content but increased with the increase in strawberry puree content in the Kochujang formulation. $b^*$-values decreased with the increases in red pepper powder content but was less affected by the strawberry puree content. Overall optimization, conducted by overlaying the contour plots under investigation, was able to point out an optimal range of the independent variables within which the six responses were simultaneously optimized. The point chosen as representative of this optimal area corresponded to strawberry puree content=14.36% and red pepper powder content=11.33%, conditions under which the model predicted soluble solids content=$59.31^{\circ}Brix$, moisture content=45.30% (w.b.), water activity=0.758, $L^*$-value=24.81, $a^*$-value=7.250, and $b^*$-value=10.19.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.185-189
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• 2007

Quality characteristics of kochujang prepared with strawberry puree (10, 20, and 30% on the total weight basis) were investigated after 30 and 300 days of storage. The moisture content of strawberry kochujang at 300 days was considerably higher than that of strawberry kochujang at 30 days and increasing strawberry content from 0 to 30% significantly increased moisture content of kochujang progressively (p<0.05). Water activity and titratable acidity also showed similar trends, but pH showed the reverse trend with the highest value in control at 30 days and the lowest value in 30% strawberry kochujang at 300 days. As the strawberry puree content increased, amino-nitrogen content consistently and correspondingly decreased. Amino-nitrogen content at 300 days was higher than that of strawberry kochujang at 30 days. Soluble solids content also showed a similar trend, but soluble solid content at 300 days was considerably lower than that of strawberry kochujang at 30 days. Reduction in soluble solids content with increasing strawberry concentration was more evident at 30 days than at 300 day.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.752-758
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• 2012

We conducted this study to investigate the quality and antioxidant properties of saccharified strawberry gruel with different ratios of strawberry rice mash. Different samples of saccharified strawberry gruel with different ratios of strawberry puree were prepared, and the proximate composition, sweetness, pH, acidity, color difference, texture, free sugar, sensory evaluation, and physiological activities of the sample were measured. With increasing strawberry puree content, the proximate compositions, sweetness, and total acidity of the strawberry gruel increased, and pH decreased significantly (p<0.05). Saccharified strawberry gruel prepared with 15% to 45% strawberry puree displayed significantly lower viscosity. As the amount of strawberry puree increased, the Lvalue, and b-value decreased, whereas the a-value increased. The free sugar content of fructose, glucose, maltose, sucrose, and total free sugar increased significantly (p<0.05). Strawberry gruel with 30% added strawberry puree was the most preferred for, its color, flavor, taste, texture, and overall acceptability preference. With increasing strawberry puree content, the total polyphenol contents, total flavonoid contents, DPPH, and ABTS radical scavenging of strawberry gruel increased significantly (p<0.05). From these results, we found that adding 30% strawberry puree was the best way to make gruel with high sensory qualities.

• Preventive Nutrition and Food Science
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• v.13 no.2
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• pp.112-116
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• 2008

Quality characteristics of kochujang prepared with strawberry puree (10, 20, and 30% on a total weight basis) were investigated at 30 and 300 days of fermentation. The highest $L^*$-value was found in 30% strawberry kochujang at 300 days of fermentation. In contrast, the highest degree of redness ($a^*$) was observed in 30% strawberry kochujang at the early stage of fermentation. During the fermentation, values of $L^*$, $a^*$, and $b^*$ increased except $a^*$-value of 30% strawberry kochujang, indicating proper substitution of strawberry puree could preserve the desired color of kochujang. After 300 days of fermentation, hardness, gumminess, and chewiness increased while adhesiveness decreased significantly (p<0.05). Taste score and Pearson coefficient between sensory and strawberry concentration revealed that 10% strawberry kochujang was more acceptable than the others, due to color and the formation of flavor compounds during the fermentation and these compounds enhanced the flavor of kochujang.

• Korean journal of food and cookery science
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• v.29 no.6
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• pp.725-731
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• 2013

This study investigates the quality of strawberry jam containing different quantities of strawberry. Strawberry jam was prepared by the addition of 70-30%(w/w) strawberry puree, Sweetness, pH, total acidity, color, anthocyanin and pectin content, texture, free sugar, and organic acid content of the samples were measured. Decrease in the quantity of the strawberry puree led to a decrease in the following: total acidity(significance value p<0.05), anthocyanin, pectin, total free sugar, frutose, glucose, sucrose, and, organic acid content, namely oxalic acid, citric acid, malic acid, succinic acid, and formic acid. A texture profile analysis showed reduction in the hardness, gumminess, and chewiness of the jam. At the same time, decrease in the puree quantity also led to an increase in the sweetness, pH, L-value, a-value and b-value(significance value p<0.05) of the jam. These results promote, the consumption of fruit that are high in fruit, low in sugar, and do not contain any chemical additives.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1518-1524
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• 2016

This study was performed to minimize quality degradation of concentrated strawberry puree after $90^{\circ}C$ for 5 min by heat treatment with citric acid (CA) and acidic sodium metaphosphate (ASM) as pH modifiers. The highest color value was 1% CA+1% ASM (13.027), followed by 1% CA (9.539) and control (6.905). Anthocyanin contents were also 1% CA+1% ASM (3.049 mg/100 g), 1% CA (1.140 mg/100 g), and control (0.757 mg/100 g) in sequence. The DPPH radical scavenging activities of control, 1% CA, and 1% CA+1% ASM were 58.148, 72.638, and 83.736%, respectively. The color values, anthocyanin contents, and DPPH radical scavenging activities were significantly different at P<0.05 between control and 1% CA+1% ASM treatment. For the results of overall preference for hedonic test, there was no significant difference at P>0.05 among the three samples. During heat treatment, quality degradation of concentrated strawberry puree was reduced by 1% CA+1% ASM treatment, which is expected for new acidulants.

• Food Engineering Progress
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• v.13 no.2
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• pp.110-116
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• 2009

Gochujang, a fermented traditional Korean hot pepper-soybean paste, has long been used to provide hot, sweet, and savory tastes. Changes in the pH, titratable acidity, moisture content, water activity, amino-nitrogen content, NaCl content, color, and yeast population during aging were investigated using a model system of Gochujang incorporated with strawberry puree up to 14% as a value-added food ingredient. pH decreased slowly till 60 days of aging then increased afterwards. Titratable acidity, on the other hand, increased during aging, reaching at the highest level at the 60 days of aging and then decreased rapidly. The moisture content continually increased during aging up to 90 days whereas water activity decreased rapidly till 60 days of aging and then slightly increased. The amino-nitrogen content increased while NaCl content decreased continually during aging. All the color parameters including L$^{*}$, a$^{*}$, and b$^{*}$-values increased during aging in general with exception for b$^{*}$-values in some conditions. Initial yeast population was ranged 1.2-4.9${\times}10^{6}$CFU/g and increased to 1.1-5.9${\times}10^{7}$CFU/g after 90 days of aging.

• Journal of Applied Biological Chemistry
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• v.59 no.3
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• pp.189-201
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• 2016

A processing factor (PF) has been used to define the maximum residue limits of pesticide in a variety of processed fruit products. This study summarizes PF by the stage of fruit processing based on JMPR reports from 2010 to 2014. When we compared PF of 19 pesticides in apple products during the processing of washing, drying, canning, juice, sauce, puree and pomace, PF was higher than 1 only in pomace. In the comparison of 21 pesticides during the process of grape (washing, juice, wine and raisin), PF was higher than 1 in raisin. In the comparison of 19 pesticides during the process of orange (juice, oil and marmalade), PF was higher than 1 in oil. When 27 pesticides were compared during the process of tomato (juice, puree and paste), paste showed the highest PF value except pomace. During the process of plum (washing, drying and puree) with 12 pesticides, PF was higher than 1 in drying. The correlation coefficients between physical characteristics of pesticide (fat-solubility and volatility) and PF were statistically significant in the processes of apple juice, orange juice, tomato puree and paste and strawberry jam.

• Food Science and Preservation
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• v.17 no.2
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• pp.190-195
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• 2010

Pressure, used as a minimal processing technology in the food industry, is a valuable tool ensuring microbiologically safe, shelf-stable fruit and vegetable production. Pressure could be used to deliver a greater variety of minimally processed products, as demanded by today's consumers. Weevaluated the effect of <400 MPa pressure, applied during chilling, on fresh fruit purees (strawberry, kiwi, aloe, and pomegranate) and vegetable extracts (from carrot and spinach) during cold storage (<$10^{\circ}C$) for 15-20 days. Samples were prepared in a processing facility in which total plate counts of falling and floating bacteria were controlled at $1{\times}100-10^1$ CFU/plate and $1{\times}10^2-10^3$ $CFU/m^3$ under conditions of $21-25^{\circ}C$ and 55-60% relative humidity. The aerobic plate counts of raw materials were less than $1{\times}10^3$ CFU/g. Evaluation parameters included microbiological safety, vitamin content, and sensory qualities. Although the overall quality of non-treated samples deteriorated with storage time at $10^{\circ}C$, samples pressurized at 250-350 MPa at $5-7^{\circ}C$ for 10 min showed less change, with no significant difference in microbiological safety, vitamin content, or sensory quality. The use of pressure extended the shelf-life during storage at $10^{\circ}C$.