Evaluating Freshness Loss of Green Tea with Q10 Method and Weibull Hazard Analysis under Accelerated Shelf Life Testing

The important quality of green tea is freshness, but high temperature, light, oxygen, and humidity during storage may reduce the freshness of green tea. Thus, this study investigated the freshness loss of green tea (FLGT) under an accelerated shelf-life testing (ASLT) by sensory evaluation and acceptability test. The FLGTs of the samples stored at 20°C, 30°C, and 40°C, were determined as 67 days, 55 days, and 45 days, respectively by the Q10 method. In addition, they were further determined as 67 days, 57 days, and 42 days, respectively, by the Weibull Hazard Analysis (WHA). The sensory evaluation and acceptability test confirmed the correctness of the above results by 2-alternative choice analysis and chemical analysis. The Q10 method was applied to predict the FLGTs stored at 4°C and −20°C which were 93 days and 150 days, which was further verified by 2-alternative choice analysis and chemical analysis. The results show that it is possible to predict the suitable drinking period of green tea during storage by the Q10 method.

Nonlinear Tactile Estimation Model based on Perceptibility of Mechanoreceptors improves Quantitative Tactile Sensing

Tactile sensing has attracted significant attention as a tactile quantitative evaluation method because the tactile sensation is an important factor while evaluating consumer products. While the human tactile perception mechanism has nonlinearity, previous studies have often developed linear regression models. In contrast, this study proposes a nonlinear tactile estimation model that can estimate sensory evaluation scores from physical measurements. We extracted features from the vibration data obtained by a tactile sensor based on the perceptibility of mechanoreceptors. In parallel, a sensory evaluation test was conducted using 10 evaluation words. Then, the relationship between the extracted features and the tactile evaluation results was modeled using linear/nonlinear regressions. The best model was concluded by comparing the mean squared error between the model predictions and the actual values. The result implies that there are multiple evaluation words suitable for adopting nonlinear regression models, and the average error was 43.8% smaller than that of building only linear regression models.

Physico-chemical and Sensory Evaluation of Biscuits Developed from Blends of Jowar (Sorghum), Organic Jaggery and Whole Wheat Flours

Background: Jowar (Sorghum) is one of the most popular millet grown in tropical and semi-arid regions. The present study was aimed to design and develop the process technology for the preparation of biscuits from blends of jowar and jaggery by replacing wheat flour. Methods: The biscuits were analysed for physico-chemical and sensory properties. The proportions taken were 30:70:60, 40:60:60, 50:50:60, 60:40:60, 70:30:60 and 100:0:60 of jowar flour, whole wheat flour and jaggery respectively. Sensory evaluation was performed by using composite scoring test and means were evaluated by Krushkal Walli H-Test. Result: Sensory evaluation revealed that the ratio of 100:0:60 (SWJ 6) jowar, whole wheat flour and jaggery has highest acceptability and was considered for further studies. The physical parameters of biscuits such as mass (20 g), thickness (7 mm), spread factor (64.28), diameter (45 mm) and color values were determined. The texture analysis revealed that the biscuits held hardness (32.5 g), fracturability (8.60 mm) and cutting strength (3.390 kg). Proximate analysis was estimated as energy (583 kcal), carbohydrate (92.6 g), protein (10.8 g), fat (4.8 g), crude fibre (8.6 g), calcium (46 mg), zinc (58.3 mg), iron (16.1 mg) and potassium (420 mg) per 100 g for SWJ 6 proportion.

Characteristics of reduced fat mayonnaise using pumpkin flour (Cucurbita moschata) as fat replacer

Reduced fat mayonnaise has the disadvantage of destabilization of emulsion. Emulsion destabilization that occurs is the separation of oil and water. Pumpkin flour is used to increase the viscosity and stability of the emulsion. The objective of this study was to determine the best percentage of the use of pumpkin flour in reduced fat mayonnaise based on pH, emulsion stability, moisture content, and sensory evaluation. The material used in this research was mayonnaise made from egg yolk, canola flower oil, vinegar, pumpkin flour as a fat replacer carbohidrates based, and other optional ingredients. The method used was an experimental laboratory with a completely randomized design with 4 treatments and 4 replications. The treatments consisted of without the use of pumpkin as a control, the use of pumpkin flour 2%, 4%, and 6% of the total oil used. The variables measured were pH, emulsion stability, moisture content, and sensory evaluation. The results showed that the use of pumpkin flour on mayonnaise gave highly significant effect on pH, stability emulsion, moisture content and increased panelists preferences. The conclusion of the study that using 6% pumpkin flour produced the best reduced-fat mayonnaise.