• 제목/요약/키워드: titratable acidity (TA)

검색결과 70건 처리시간 0.028초

김치 발효산물에 대한 발색지시계의 온도별 민감성 (Sensitivity of Color Indicators to Fermentation Products of Kimchi at Various Temperatures)

  • 홍석인;박완수
    • 한국식품과학회지
    • /
    • 제29권1호
    • /
    • pp.21-25
    • /
    • 1997
  • 소포장 김치의 발효, 숙성정도를 연속적으로 신속하게 감지할 수 있는 기술을 개발하고자 색 지시계를 적용하였다. $CO_2$ 흡착제/발색시약의 혼합물로 구성된 지시계를 포장재에 도입하여 화학반응에 의한 색깔 변화와 저장 중 김치의 pH, 산도 변화를 측정 비교하므로서 숙성도를 감지하였다. 김치의 발효 숙성이 진행되면서 포장재 내부에 부착되어 있던 지시계 BP와 MR은 초기의 하늘색에서 보라색으로, 연한 노란색에서 빨간색으로 점차 색이 변하였으며, 이러한 지시계의 색 변화는 저장온도에 관계없이 pH 또는 산도 변화와 높은 상관관계를 가지므로서 김치의 숙성정도를 잘 나타내었다. 결과적으로 상품 김치의 저장 유통과정에서 포장을 뜯지 않고도 내용물의 숙성도를 육안으로 감지할 수 있는 숙성 감지용 지시계의 적용 가능성을 확인할 수 있었다.

  • PDF

Evaluation of Time-Temperature Integrators (TTIs) with Microorganism- Entrapped Microbeads Produced Using Homogenization and SPG Membrane Emulsification Techniques

  • Mijanur Rahman, A.T.M.;Lee, Seung Ju;Jung, Seung Won
    • Journal of Microbiology and Biotechnology
    • /
    • 제25권12호
    • /
    • pp.2058-2071
    • /
    • 2015
  • A comparative study was conducted to evaluate precision and accuracy in controlling the temperature dependence of encapsulated microbial time-temperature integrators (TTIs) developed using two different emulsification techniques. Weissela cibaria CIFP 009 cells, immobilized within 2% Na-alginate gel microbeads using homogenization (5,000, 7,000, and 10,000 rpm) and Shirasu porous glass (SPG) membrane technologies (10 μm), were applied to microbial TTIs. The prepared micobeads were characterized with respect to their size, size distribution, shape and morphology, entrapment efficiency, and bead production yield. Additionally, fermentation process parameters including growth rate were investigated. The TTI responses (changes in pH and titratable acidity (TA)) were evaluated as a function of temperature (20℃, 25℃, and 30℃). In comparison with conventional methods, SPG membrane technology was able not only to produce highly uniform, small-sized beads with the narrowest size distribution, but also the bead production yield was found to be nearly 3.0 to 4.5 times higher. However, among the TTIs produced using the homogenization technique, poor linearity (R2) in terms of TA was observed for the 5,000 and 7,000 rpm treatments. Consequently, microbeads produced by the SPG membrane and by homogenization at 10,000 rpm were selected for adjusting the temperature dependence. The Ea values of TTIs containing 0.5, 1.0, and 1.5 g microbeads, prepared by SPG membrane and conventional methods, were estimated to be 86.0, 83.5, and 76.6 kJ/mol, and 85.5, 73.5, and 62.2 kJ/mol, respectively. Therefore, microbial TTIs developed using SPG membrane technology are much more efficient in controlling temperature dependence.

식초기반 샐러드 드레싱용 다시마 식초 제조 및 이화학적 특성 (Preparation and Physicochemical Characterization of Sea Tangle Vinegar for Utilization as Vinegar-Based Salad Dressing)

  • 한아름;서정희
    • 한국식품조리과학회지
    • /
    • 제33권3호
    • /
    • pp.300-306
    • /
    • 2017
  • Purpose: This study aimed to prepare sea tangle vinegar and test its applicability as a vinegar-based functional salad dressing in terms of physicochemical properties. Methods: Sea tangle vinegar was prepared by mixing sea tangle with sugar and vinegar and fermenting the mixture at room temperature for 3 months. The resulting sea tangle vinegar was examined for its physicochemical properties and antioxidant activity with brewed vinegar and persimmon vinegar as controls. Results: The sea tangle vinegar showed significantly higher viscosity than control vinegars, and shear thinning behavior that is typical for salad dressing containing polymers. In addition, storage modulus (G′) of sea tangle vinegar was relatively high in dynamic viscosity measurement while that of control vinegars remained negligible. Together with the high soluble solids content of sea tangle vinegar, rheological behavior indicates that sea tangle vinegar had soluble polysaccharides extracted from sea tangle, consequently leading to an increase in viscosity. Titratable acidity (TA) and pH were 2.52% and 3.58, respectively, which satisfies the TA and pH requirements for microbiological safety of a salad dressing. Absorbance at 285 nm and Folin Ciocalteu's reagent method revealed that sea tangle vinegar contained antioxidative phenolic compounds. Conclusion: This study demonstrates that sea tangle vinegar could be potentially developed as a vinegar-based functional salad dressing when combined with sensory evaluation in the future.

Application of a Prototype of Microbial Time Temperature Indicator (TTI) to the Prediction of Ground Beef Qualities during Storage

  • Kim, Yeon-Ah;Jung, Seung-Won;Park, Hye-Ri;Chung, Ku-Young;Lee, Seung-Ju
    • 한국축산식품학회지
    • /
    • 제32권4호
    • /
    • pp.448-457
    • /
    • 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.

Use of hot water, combination of hot water and phosphite, and 1-MCP as post-harvest treatments for passion fruit (Passiflora edulis f. flavicarpa) reduces anthracnose and does not alter fruit quality

  • Dutra, Jaqueline Barbosa;Blum, Luiz Eduardo Bassay;Lopes, Leonardo Ferreira;Cruz, Andre Freire;Uesugi, Carlos Hidemi
    • Horticulture, Environment, and Biotechnology : HEB
    • /
    • 제59권6호
    • /
    • pp.847-856
    • /
    • 2018
  • This research aimed to evaluate the effectiveness of hot water ($43-53^{\circ}C{\cdot}5min^{-1}$; $47^{\circ}C{\cdot}2-6min^{-1}$), 1-methylcyclopropene (1-MCP) at $50-300nL\;L^{-1}$ and a combination of hot water ($47/49^{\circ}C{\cdot}5min^{-1}$) and phosphite $40%\;P_2O_5+20%\;K_2O$;$40%\;P_2O_5+10%\;Zn$) in anthracnose control and the effect on fruit quality [fresh weight loss (FWL-%); pH, total soluble solids ($TSS-^{\circ}Brix$), and titratable acidity (TA = % citric acid (CA)] of passion fruit ( Passiflora edulis f. flavicarpa ) at the postharvest stage. When the fruits were in the stage of 0% dehydration and fully yellow peels, they were disinfested and inoculated with Colletotrichum gloeosporioides. They were then subjected to the above mentioned treatments; this was followed by incubation for 120 h. The diameter of the disease lesions was monitored daily. After the incubation, a physico-chemical analysis was performed. Hot-water treatment resulted in disease reduction at 47 and $49^{\circ}C$ for 4 and 5 min. The combination of hot-water treatment at $47^{\circ}C$ (4 or 5 min) and application of the phosphite of K or Zn significantly reduced disease severity in fruits. The 1-MCP treatment reduced anthracnose severity in passion fruit mainly at $200nL\;L^{-1}{\cdot} 24h^{-1} $. None of the treatments significantly changed the physico-chemical characteristics of the fruit [FWL (2.6-4.1%); pH (3.2-3.5), TSS ($8.9-10.9^{\circ}Brix$), and TA (1.8-2.5% CA)].

저온저장 자두를 이용한 자두 퓨레의 품질특성과 항산화 활성 (Quality Characteristics and Antioxidant Activity of Puree Made with Plums Stored at Low Temperatures)

  • 박명빈;박사무엘;여채은;김건오;전익조;조영은;성지혜
    • 한국식생활문화학회지
    • /
    • 제36권1호
    • /
    • pp.84-91
    • /
    • 2021
  • The oriental plum (Prunus salicina) is one of the most popular fruits in Korea due to its sweet taste and pleasant aroma. The objective of this study was to analyze the quality characteristics and antioxidant activities of a puree made using plums stored at low-temperatures. The quality characteristics were determined by estimating total soluble solids (TSS, °Brix), titratable acidity (TA, % citric acid), TSS/TA ratio, pH, colors, sugar content, and sensory profiles. The antioxidant effects were estimated by total polyphenol and flavonoid content and radical scavenging activity. The results showed that the plum puree containing both the flesh and the peel had markedly higher red coloration (a⁎ value) than the puree without the peel, while yellow coloration (b⁎ value) and lightness (L⁎ value) were lower in the puree without the peel than with the peel. The sensory qualities including the plum taste and flavor, texture as well as overall acceptance showed no significant variation between the samples. Meanwhile, the total polyphenol/flavonoid content and radical scavenging activities were significantly improved by the presence of fruit peel and by frozen storage. These findings suggest that frozen plums could be a suitable ingredient for making a puree and concentrate for the food manufacturing industry.

액상형 고령친화식품의 치아부식능 평가 (Assessment of the erosive potential of elder-friendly foods)

  • 정은하;강정윤;한선영
    • 한국치위생학회지
    • /
    • 제22권5호
    • /
    • pp.461-468
    • /
    • 2022
  • Objectives: To investigate the effect of several elder-friendly foods on oral health and suggest guidelines for proper food intake. Methods: Six elderly-friendly foods (liquid type) and two control groups (mineral water and mixed coffee) were selected for this study. The pH of the food was measured using a calibrated pH meter, and the titratable acidity was determined using 1 M NaOH until 7.0 (TA 7.0). The screening method suggested by the International Organization for Standards was performed using an undersaturated hydroxyapatite solution to determine the difference between the initial and final pH of the screening solution (△pH). In addition, the sugar content was measured and expressed as Brix (%). Results: All the elder-friendly foods tested in this study showed a neutral pH (6.68-7.35), similar to mineral water (pH 7.84). The range of TA 7.0 values was 0.00-0.54 ㎖. The changes in pH determined using the screening solution confirmed that the largest change in pH was found in Careon (△pH 1.14±0.02), which has no erosive potential. Nevertheless, all elder-friendly foods had higher sugar content than the negative control group. Conclusions: Low tooth erosive potential was found in elder-friendly foods, but these foods showed high sugar content.

쌀막걸리를 첨가한 요구르트의 품질특성에 관한 연구 (A Study on the Quality Properties of Yogurt containing Makgeolli (Korea Rice-Wine))

  • 이재성;배인휴
    • Journal of Dairy Science and Biotechnology
    • /
    • 제35권2호
    • /
    • pp.135-142
    • /
    • 2017
  • 본 연구는 쌀막걸리를 요구르트 제조시 5.0%, 10.0% 그리고 20.0% 비율로 첨가하여 배양중과 저장중에 pH, TA, 생균수, 점도, 유청분리현상, 가스생성량을 측정하였으며, 완제품에 대해 알코올 함량 및 관능을 분석하였다. 배양 중 pH와 TA의 변화는 막걸리 자체 낮은 pH로 인해 대조구에 비해 높은 산생성력을 나타내었으며, 배양 중 유산균수의 결과 대조구보다 첨가구에서 높은 유산균수를 나타내었다. 배양중 점도의 결과 배양 5시간까지 대조구보다 첨가구에서 높은 점성을 나타내었으며, 유청분리현상은 대조구와 5.0% 첨가구에서는 안정성이 확인되었으나 10.0%와 20.0% 첨가구에서는 배양시간이 경과 될 수록 높은 유청분리현상을 확인 할 수 있었다. 배양 중 가스 발생량은 첨가량이 많을 수록 높은 발생량을 보였으며, 저장중 발생량은 저장 4일차부터 모든 시험구에서 점차적으로 감소하는 경향을 나타내었다. 저장 중 알코올 함량은 20.0% 첨가구를 제외한 나머지 시험구에서는 발생되지 않았다. 완제품에 대한 관능검사 결과 전반적인 기호도에서 대조구가 높은 점수를 보였지만 감미료 사용 시 대조구와 유사한 관능평가가 기대된다. 이로써 요구르트 제조시 쌀막걸리를 5.0% 첨가 시 제조 시간 단축 및 쌀 막걸리의 기능성이 가미된 기능성 요구르트 제조가 가능할 것으로 사료된다.

Are Vitamin Beverages Good for Dental Health?

  • Kang, A-Reum;Park, Su-Hee;Woo, Jung-Woong;Hong, Da-Jung;Kim, Kyu-Ri;Sung, Chi-Yeong;Woo, Ji-Yeon;Jeong, Ju-Hui;Jung, Eun-Ha
    • 치위생과학회지
    • /
    • 제20권1호
    • /
    • pp.9-15
    • /
    • 2020
  • Background: Although the consumption of vitamin beverages has increased because of the recent interest in health and beauty, guidelines addressing appropriate consumption habits are lacking. Thus, the aim of this study was to investigate the erosive potential of several vitamin beverages and to propose guidelines for the appropriate intake of these drinks. Methods: Five vitamin beverages were selected after a pre-investigation of the current beverage market. Coca-Cola and mineral water were selected as the control beverages. The pH of the beverages was measured with a calibrated pH meter, and the titratable acidity (TA) was determined by using 1 M sodium hydroxide to reach pH 5.5 (TA5.5) and 7.0 (TA7.0). The screening method suggested by the International Organization for Standardization was used to measure pH variation (ΔpH) by using an under-saturated hydroxyapatite solution to determine the difference between the initial and final pH of the screening solution. All measurements were performed in triplicate. Results: All vitamin beverages tested in this study exhibited a low pH (2.53~2.99), similar to Coca-Cola, which is known to be a highly acidic beverage. The highest TA5.5 and TA7.0 values of the vitamin beverages were 7.03 ml and 8.81 ml, respectively. The largest change in pH determined by using the screening solution was found in Bacchus D (ΔpH 1.44±0.05). The mean ΔpH of the vitamin beverages was 1.12±0.29, which was higher than that of Coca-Cola (positive control, ΔpH 0.58±0.05). Conclusion: Vitamin beverages exhibited an erosive potential capable of damaging enamel surfaces. Therefore, the frequency of vitamin beverage intake should be limited, and individuals consuming these drinks should try to restore normal oral pH as quickly as possible.

수확 전·후 1-MCP처리가 '후지' 사과의 저온저장 중 과실품질에 미치는 영향 (Effect of Preharvest and Postharvest 1-Methylcyclopropene (1-MCP) Treatments on Fruit Quality Attributes in Cold-stored 'Fuji' Apples)

  • 유진기;강봉국;이진욱;김대현;이동훈;정희영;최동근;정명근;최인명;강인규
    • 원예과학기술지
    • /
    • 제33권4호
    • /
    • pp.542-549
    • /
    • 2015
  • 본 연구는 수확 전 수체살포용 1-MCP($Harvista^{TM}$)와 수확 후 훈증용 1-MCP($SmartFresh^{TM}$) 처리가 '후지' 사과의 품질과 저장성에 미치는 영향을 구명하고자 실시하였다. $Harvista^{TM}$ 처리는 수확 1, 2, 3주전 0, 95, 125, $250mg{\cdot}L^{-1}$ 농도로 각각 처리하였으며, $SmartFresh^{TM}$ 처리는 수확 1일 후 밀폐된 공간에서 $1{\mu}L{\cdot}L^{-1}$의 농도로 18시간동안 처리하였다. 과실저장은 $0{\pm}1^{\circ}C$ 조건에서 180일간 저장하였다. $Harvista^{TM}$ 처리에 따른 수확 시 과실품질을 보면 과중, 과피 적색도, 내생에틸렌 발생량, 경도, 산 및 가용성 고형물 함량은 무처리구와 차이가 없었다. 저온저장동안 '후지' 사과의 품질변화를 보면 $Harvista^{TM}$$250mg{\cdot}L^{-1}$의 농도로 2, 3주전에 처리한 과실이 무처리구에 비하여 과실 경도 및 산 함량이 더 높게 유지되었으며, 내생에틸렌 발생량도 무처리구에 비하여 5.5-10.0% 수준으로 현저히 낮았다. 그리고 저장기간 중 가용성고형물 함량은 차이를 보이지 않았다. $Harvista^{TM}$ 단독처리와 $Harvista^{TM}+SmartFresh^{TM}$ 혼용처리구는 경도, 산 함량, 내생에틸렌 발생량 모두 저장 180일 후에도 수확 시와 큰 차이를 보이지 않아 과실품질이 유지되었다. 요인간 상관분석은 $Harvista^{TM}$ 처리시 처리농도와 무관하게 내생에틸렌 발생량이 경도 또는 산 함량과 부의 상관관계를 나타냈다. 그리고 $Harvista^{TM}+SmartFresh^{TM}$ 혼용처리 시 $Harvista^{TM}$ $250mg{\cdot}L^{-1}$$SmartFresh^{TM}$ 처리가 변수간 정의 상관관계를 나타내었다. 따라서, 수확 후 $SmartFresh^{TM}$처리에 의한 과실품질유지 효과와 함께, 고 농도의 $Harvista^{TM}$처리 또한 저온저장 중 과실품질 유지에도 큰 효과를 보였다.