• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.173-180
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• 2022

There are a number of methods to evaluate the quality of squid. However, when purchasing the fish, consumers and retails rely only on the sensory test and flavor in the field. Therefore, this study was aimed to prove relationship between scientific indicator and sensory test. Total viable cell count (TVC), viable cell count of Pseudomonas spp., pH and volatile basic nitrogen (VBN) were selected as scientific indicators and mesured during the storage of squid at different temperature. The squid was storaged at 3 different temperature (5℃, 15℃, 20℃). Off flavor determination time was measured by R-index, and kinetic modeling was conducted. Activation energies of off-flavor determination time, TVC, Pseudomonas spp, VBN, and pH were 51.210 kJ/mol, 42.88 kJ/mol, 50.283 kJ/mol, 72.594 kJ/mol and 41.99 kJ/mol respectively. Activation energy of off-flavor determination time was approximated to viable cell count of Pseudomonas spp., TVC, pH and VBN as an order. Especially, viable cell count of Pseudomonas spp. had best match of the activation energy. Therefore, it was judged that indicator of off-flavor determine time was viable cell count of Pseudomonas spp..

• Food Science of Animal Resources
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• v.29 no.3
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• pp.325-333
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• 2009

Beef quality indicators of off-flavor development during storage were investigated in terms of temperature dependence. The off-flavor development time (ODT) was detected using the R-index sensory test. During varying storage conditions at $25^{\circ}C$, $15^{\circ}C$, and $5^{\circ}C$, elements of beef quality were measured, such as volatile basic nitrogen (VBN), pH, color (CIE $L^*$, $a^*$, $b^*$), Warner-Bratzler shear force (WBSF), Pseudomonas spp. CFU, and lactic acid bacteria (LAB) CFU. A model with temperature dependence of ODT during storage was developed using Arrhenius-like equation, and a requirement with quality indicators was mathematically derived, resulting in similar temperature dependence. The temperature dependence of beef quality indicators was represented by the Arrhenius activation energy (Ea). Upon comparing the Ea of beef quality indicators and ODT, the temperature dependence similarity was found to be higher in the order of three groups: VBN, pH, $a^*$ value; LAB, Pseudomonas spp.; and WBSF, $L^*$ value, $b^*$ value. Therefore, VBN were determined as the most effective indicator of beef quality during off-flavor development.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.309-315
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• 2010

A grilled-type shrimp flavor was developed through the Maillard reaction to reduce or mask fish odor or off-flavor in seafood. Model systems were created by using enzymatic hydrolysate of shrimp and adding precursors to increase flavor quality and stability. Amino acid precursors such as cysteine and methionine, sugar precursors such as glucose, xylose, ribose, and sucrose, and one particular compound of glucosamine were tried and their flavor qualities were tested by sensory evaluation. Also, the optimum reaction condition was investigated using the pH values of pH 5, 6, 7, and 8 with reaction times of 1 hr, 2 hr and 3 hr after the best precursors were determined. The best condition of the precursors for grilled-type shrimp flavor was the mixtures of methionine, threonine, xylose, and glucosamine. The optimum reaction condition was at pH 8.0 and 2 hr reaction time.

• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.304-308
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• 2010

Boiled-type shrimp flavor was developed using Maillard reaction to reduce or mask fish odor or off-flavor in seafood. Model systems were created using enzymatic hydrolysate of shrimp and adding precursor compounds to increase flavor quality and stability. Amino acid precursors of cysteine and methionine and sugar precursors such as glucose, xylose, ribose and sucrose were tried and their flavor qualities were tested by sensory evaluation. After the optimal precursors were determined, the optimum reaction condition was investigated using pHs of 5, 6, 7, and 8 and reaction times of 1, 2 and 3 hours. The best precursors for boiled-type shrimp flavor were methionine and sucrose. The optimum reaction condition was pH 8.0 and a one hour reaction time.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.6
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• pp.881-890
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• 2019

Objective: A study was conducted to develop non-dairy creamer analogs/mimics using egg white, egg yolk, soy protein and their combinations, and their nutrient content, shelf-life and flavor acceptability were compared. Methods: Spray dried egg white, egg yolk, and soy protein isolate were purchased from manufacturers and used for the formulae. Results: The protein contents of the non-dairy creamer analogs/mimics were about 8.5% as calculated. The amounts of oleic and linoleic acid content increased as the amount of yolk increased in the formula, but the increases of polyunsaturated fatty acids were <0.5% of total fat. Addition of egg yolk to the formula increased choline and lutein content in the products, but the amounts were <0.4 mg/g for choline and $4{\mu}g/g$ for lutein. The lutein in the products continued to decrease over the storage time, and only about 15% to 20% of the 0-month amounts were left after 3 months of storage. Although the thiobarbituric acid reactive substances values of the spray-dried non-dairy creamer analogs/mimics increased as storage time increased, the values were still low. Yellowness, darkness, and egg flavor/odor of the non-dairy creamer analogs/mimics increased as the amount of egg yolk in the formula increased. The overall acceptability of the non-dairy creamer analogs/mimics was closely related to the intensity of egg flavor/odor, but storage improved their overall acceptance because most of the off-odor volatiles disappeared during the storage. Water temperature was the most important parameter in dissolving spray-dried non-dairy creamer analogs/mimics, and $55^{\circ}C$ to $75^{\circ}C$ was the optimal water temperature conditions to dissolve them. Conclusion: Higher amounts of yolk and soy protein combinations in place of egg white reduced the cost of the products significantly and those products contained better and balanced nutrients than the commercial coffee creamers. However, off-flavor and solubility were two important issues in the products.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.3
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• pp.357-364
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• 2012

Quality characteristics of sausage with added pine needle powder (0%, 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%) as an ingredient. The basic ingredients of sausage consisted of pork meat 60%, olive oil 20%, and ice water 20%. Sensory properties of sausage were analyzed by a sensory test, and the texture and color characteristics were measured using a texturometer and color meter, respectively. In the results of the sensory test, taste, texture, and overall preference were highest in the sample with added 1.5% pine needle powder. The sausage with added 1.5% pine needle powder was moderate in color intensity, pine needle flavor, and astringent taste. Hardness and gumminess of sausage were higher in 1.0% and 1.5% pine needle powder. However, springness and chewiness of sausage showed no significant differences. In terms of color intensity of sausage, L-value and a-value were lower and b-value was higher, depending on the pine needle powder amount. Development of off-flavor of sausage during storage was greater in 0% and 1.5% added sausages than in 2.0% sausage with increasing storage time. As a conclusion, sausages with added 1.5% and 2.0% pine needle powder were the most suitable for making functional sausage with added pine needle powder.

• Food Science of Animal Resources
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• v.32 no.4
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• pp.448-457
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• 2012

The predictive ability for off-flavor development and quality change of ground beef was evaluated using a microbial time temperature indicator (TTI). Quality indices such as off-flavor detection (OFD) time, color, pH, volatile basic nitrogen (VBN), aerobic mesophilic bacteria (AMB) counts, and lactic acid bacteria (LAB) counts were measured during storage at 5, 10, 15, and $25^{\circ}C$, respectively. Arrhenius activation energies (Ea) were estimated for temperature dependence. The Ea values for TTI response (changes in titratable acidity (TA)), VBN, AMB counts, LAB counts, and freshness, which is defined based on OFD time for quality indices of ground beef, were 106.22 kJ/mol, 58.98 kJ/mol, 110.35 kJ/mol, 116.65 kJ/mol, and 92.73 kJ/mol, respectively. The Ea of microbial TTI was found to be closer to those of the AMB counts, LAB counts, and freshness. Therefore, AMB counts, LAB counts, and freshness could be predicted accurately by the microbial TTI response due to their Ea similarity. The microbial TTI exhibited consistent relationships between its TA change and corresponding quality indices, such as AMB counts, LAB counts, and freshness, regardless of storage temperature. Conclusively, the results established that the developed microbial TTI can be used in intelligent packaging technology for representing some selected quality indices of ground beef.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.3
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• pp.195-204
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• 2010

Several quality parameters affecting Alaska pollack, Theragra chalcogramma, were measured and modeled kinetically under storage at different temperatures: the K-value, trimethylamine (TMA), volatile basic nitrogen (VBN), Torry meter, pH, acid value (AV), total viable cell count (TVC), and colony forming units (CFU) of Pseudomonas spp. The off-flavor development time (ODT) was also measured using the R-index sensory test and modeled kinetically. Among the quality parameters, the CFU of Pseudomonas spp. was an indicator of the ODT according to a similarity in the Arrhenius temperature dependence, which was derived as a criterion mathematically. The temperature dependence was represented by the Arrhenius's activation energy ($E_a$). On comparing the $E_a$ of the quality factors and the ODT, the similarity in the temperature dependence was found to be high in the order Pseudomonas spp., pH, VBN, TVC, K-value, TMA, AV, and Torry meter. Therefore, Pseudomonas spp. was identified as the primary indicator of ODT.

• Korean Journal of Ecology and Environment
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• v.50 no.3
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• pp.337-354
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• 2017

Cyanobacteria Aphanizomenon population is widely distributed in the world, and well known as harmful algae by producing toxins and off-flavor materials, thus belonging to one of the taxa that became more interested in the field of limnoecology. In this study, the frequency, intensity, and duration of Aphanizomenon occurrence were increased with the abnormal drawdown of water level in the winter in Boryeong Reservoir, and the spatial and temporal characteristics of them are compared with each other in the perspective of hydrometeorology (1998 to 2017) and limnology (2010 to 2017). In Korea, Aphanizomenon flourished mainly in high temperature, and the appearance in the low temperature was rare in total five times. The harmful cyanobacteria Aphanizomenon was observed in the low temperature (December to February) in Boryeong Reservoir from 2014, and then reached a maximum value of $2,160cells\;mL^{-1}$ in January 2017. In addition, the period exceeding $1,000cells\;mL^{-1}$ at this time was more than 3 months. This was simultaneously associated with abnormal water level fluctuation in the low temperature ($<10^{\circ}C$). The large drawdown of water level in the winter season has the potential to promote or amplify the germination and development of harmful algae. Also, subsequent water quality and ecological impacts(e.g., algal toxins and off-flavor substances) need to be considered carefully.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.271-282
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• 1982

The browning development, mainly through the Maillard reaction, occurring in the dried fish meat products during storage causes reduction of the nutritional value due to the loss of the essential amino acid such as available lysine as well as off -flavor resulting in the deterioration of the food quality thus shortening the shelflife. In the work, the changes in the amount of available lysine, extractable nitrogenous compounds (nonprotein-N, amino-N, trimethylamine oxide, trimethylamine, and free lysine) and development of browning were measured to assess the relationship between the shelflife and the quality loss in dried filefish under the steady state conditions (35,45, and $55^{\circ}C;a_{w}'s$ of 0.44 0.52, 0.65 and 0.75 at each temperature) and fluctuating temperature condition of $35/55^{\circ}C$ will. alternating 7 day periods at each water activity. The results indicated that the amount of available lysine and extractable nitrogenous compounds except TMA decreased rapidly with increasing temperatures and water activities while the rate of available lysine and extractable nitrogenous compounds must be involved in the initial stage of brown pigment formation. The available lysine loss of the dried filefish products stored under the fluctuating temperature conditions was greater than that stored under its fixed mean temperature, $45^{\circ}C$. The activation energies for lysine loss obtained from the Arrhenius plot ranged 6.9 to 4.4 Kcal/mol and $Q_{10}$ values at $40^{\circ}C$ were 1.4 to 1.2. The values for browning were 15.7 to 14.4 Kcal/mol and 2.2 to 2.0 respectively. Shelf-life, defined as the time to reach 0.15 O. D./g solid or the limit of off-color deterioration by browning reaction, was extented longer than the halflife of Iysine loss, actually corresponding $75\%$ loss of available lysine. This suggested that the halflife of lysine loss might not be adequate to assess the shelf-life of the food system with high potential of protein, nonproteinous nitrogen compounds, and lipids.