In recent years, as the Chinese consumption level increased, the consumption quantity of fresh pork had been increasing year by year. Freshness was an important index to judge the quality of pork. This study aimed to analyze freshness indices change of pork and pork exudate during storage. Thus the conclusion of this study was to characterize freshness change of pork by change law of freshness indices of pork exudate. So as to provide a reference for more convenient determination of the pork freshness. The results showed that the freshness indices of pork and their exudates change accordingly with the increase of storage time. On day 3, the pork seeped out more obvious juice. The turbidity of pork and its exudates increased gradually with the decrease of freshness, and sensory scores decreased gradually. The color changed from bright red to reddish brown and finally grey brown. The indicators of pork and their exudates (the total volatile basic nitrogen, the pH, a* and turbidity levels) were significantly correlated at the 0.01 level, the correlation coefficients were 0.9727, 0.9823, 0.9205, and 0.8765, respectively. Therefore, freshness indices of pork exudates can reflect the freshness of pork.
Increasement of demand for gayo arabica coffee has influenced the coffee industry, either in increasing the coffee production and also in increasing the usage of coffee machinery and equipment significantly. However, combustion of oil fuels result the emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) which increase the effect of greenhouse gases from the coffee production process. This study aimed to analyze the direct impact of gayo coffee production towards environment using the Life Cycle Assessment (LCA) method, including several stages such as (1) the goal and scope definition, (2) the inventory analysis, (3) the impact assessment, and (4) the interpretation. Results of this study showed that the energy needed to process 1000 kg of coffee was 7.67 MJ, while the produced liquid waste was 5 953.2 kg. The value of the global warming impact on the coffee life cycle was 56 807 165.63 CO2eq.
Adedolapo Ibironke Falodun, Helen Nwakego Ayo-Omogie and Olugbenga Olufemi Awolu
This study investigated the effect of different drying techniques on Cardaba banana flour. Cardaba banana was processed using sun, cabinet and freeze drying methods. The proximate, pasting, functional, starch profile and antioxidant properties of Cardaba banana flour were evaluated. The drying methods significantly (p ≤0.05) affected the chemical, functional, pasting and antioxidant properties of the Cardaba banana flour. Freeze dried (FD) flour sample had highest (6.69%) protein value, while sun dried (SD) flour sample had the lowest (6.13%). The crude fat of FD sample (2.38%) was not significantly different (p >0.05) from cabinet dried (CD) flour (2.38%) sample. However, sun dried sample crude fibre content was the highest (0.84%). In addition, drying methods significantly (p ≤0.05) affected the pasting characteristics of Cardaba banana flours. Results of functional properties showed that the drying methods had no effect on the least gelation properties of the flour. The resistant and total starch was highest in CD, and least in SD. Freeze drying produced flour high in indigestible carbohydrate compared to the other methods. Cardaba banana flour samples from all the drying methods showed substantive total phenolic, flavonoid, ABTS and DPPH contents. The drying methods employed significantly (p ≤0.05) affected the functional, chemical, pasting and antioxidants properties of Cardaba banana flours. However, the study indicated that freeze drying and cabinet drying produce flours with better properties.
Qiqi Zheng, Guowei Shu, Jianbo Kou, Xiuxiu Cui and Jiangpeng Meng
In order to improve the survival rate of probiotics and produce probiotic goat milk from fermented goat milk of Lactobacillus casei L61 by spray drying. Spray drying has been applied to large-scale industrial production of milk powder due to its high efficiency and low cost. However, high temperatures in spray drying can result in the loss of large numbers of probiotic.The purpose of this paper is to study the effects of eight thermal protectants including skim milk, sucrose, glucose, β-cyclodextrin, gelatin, maltodextrin, glycerol, trehalose on the survival rate and viable counts of L.casei L61 after heat treatment by the single factor experiment. All protective agents have a positive effect on increasing the survival rate of L.casei L61 (p<0.05). The results indicated that the survival rates of L.casei L61 were up to the maximum of 10.94%, 1.13%, 3.04%, 0.21%, 6.97%, 0.075, 4.71% and 0.29%, while the additions of skim milk, sucrose, glucose, β-cyclodextrin, gelatin, maltodextrin, glycerol, trehalose were 20mg/L, 10%, 7%, 15%, 1.5%, 3%, 8mL/L, 10%, respectively; the viable counts after heat treatment are 19.69, 0.81, 1.78, 0.455, 12.2, 0.12, 2.75, 0.435(×106CFU/mL), respectively. This paper provides technical a reference for the development of probiotic goat milk powder.
Guowei Shu, Chun Yin, Haipeng Qin, Haiyan Kou, Shuai He and Dan Huang
The effect of sodium tripolyphosphate, glycerol, vitamin B2, mannitol and solid malt extract on the freeze-dried powder survival rate and the viable cells of the B. bifidum BB01 were studied by single-factor test in this study. The optimal concentration of protectant for B. bifidum during freeze-drying were 1.5% (W/V) sodium tripolyphosphate, 12% (W/V) glycerol, 6% (W/V) vitamin B2, 6% (W/V) mannitol and 6% (W/V) solid malt extract, and the survival rate of bacteria was 18.63%, 22.98%, 24.13%, 24.19% and 39.77%, respectively.
Fangfang Cheng, He Chen, Ni Lei, Meng Zhang and Hongchang Wan
In present study, the effects of carbon sources (glucose, lactose, sucrose, galactose, maltose and soluble starch) and nitrogen sources (casein peptone, whey protein, soy peptone, yeast, tryptone, beef extract and peptone) on activity of cell envelope proteinases (CEP), specific activity, protein content, OD600 value and pH in MRS broth fermented by Lactobacillus plantarum LP69 were investigated by individual factor experiment. The results indicated that carbon and nitrogen sources have significant influence on the activity of CEP and specific activitys of L. plantarum LP69, glucose, maltose, casein peptone and peptone are superior to other selected carbon and nitrogen sources. The optimum concentrations of glucose, maltose, casein peptone and peptone for L. plantarum LP69 are 2%, 2%, 1% and 1%; the activity of CEP are 19.52U/mL, 21.13U/mL, 13.49U/mL and 20.61U/mL, respectively.
The purpose of this research was to screen out the optimal -producing peptide conditions for cow milk fermented by Lactobacillus bulgaricus LB6. The effects of temperature, inoculation size, time and skim milk concentration on the ACE inhibition rate of fermented milk were investigated by single factor experiment, and the optimal fermentation conditions were determined by orthogonal experiment. The conditions of the single factor experiment were: Temperatures were 37° C, 39° C, 42° C, 44° C and 46° C. The inoculation amount was 1%, 3%, 5%, 7% and 9%, the time was 8h and 10h. At 12h, 14h and 16h, the concentration of skim milk was 8%, 10%, 12%, 14% and 16%, respectively. The results showed that the optimal fermentation conditions for ACE inhibitory peptide produced by Lactobacillus bulgaricus LB6 were 4% inoculation, 13h in time, 42°C in temperature and 13% in skim milk. Under this condition, the ACE inhibition rate reached 76.50% and the OD value was 0.330. The titration acidity was 116.4°T, the pH was 4.62, and the sensory evaluation was 75 scores.
Yunfeng Hu, Liping Zhang, Jinjin Wei and Zengyu Wei
In order to study the quality changes and shelf life of chitosan coated eggs during storage, the quality, gas chamber diameter, yolk coefficient and the quality change of Hough unit during storage were measured at temperature of 5, 20 and 35 ℃. The Pearson correlation between the quality indexes and the egg Hough’s unit value was analyzed, and the yolk coefficient was analyzed dynamically and the shelf life prediction model was based on the basis of the Arrhenius equation. The results showed that the quality of eggs, egg yolk coefficient, and Huff units all decreased with the extension of storage time, and the diameter of the air chambers of eggs showed an increasing trend with the extension of storage time. Moreover, the storage environment at high temperature (20 and 35 ℃) had a significant effect on the quality deterioration than the low temperature (5℃) storage environment; The correlation coefficient between egg yolk coefficient and Hough unit is the highest at all temperatures, which can be used as an important indicator for shelf life prediction; According to the changing rule of egg quality, the yolk coefficient can establish a first order kinetic model. According to the model established by the egg yolk coefficient, the coefficient R2 of the fitting curve of the predicted value and the measured value is 0.9825, and the average relative error P is 9.32% and less than 10%. The kinetic relationship between yolk coefficient and temperature is well described. At the same time, based on the dynamic model, the shelf life prediction model of chitosan-coated eggs based on yolk coefficient was determined by the dynamic model. The average relative error was 7.6%, less than 10%, which indicated that the egg shelf life prediction model based on the change of egg yolk coefficient was feasible.
This research demonstrated the significance of variety and thermal holding time (THT) at constant temperature (95 °C) on quality characteristics of mango juice. Eighteen samples from Mado, Julie and Kent mango varieties were produced using full factorial design. Quality parameters, sensory and microbial properties were determined. Variety and THT were significant for most notable variables considered except for some sensory properties. Juice of Julie had the highest vitamin C at 60s, while Mado were superior in virtually all other chemical parameters; having 31.93 – 49.97 µg/100g pro-vitamin A, 51.10 – 113 mg/100g total phenol, 25.60 – 81.40 mg/100g total flavonoid, 1.26 – 1.48 mg/L tannin and 12.60 – 13.60% °Brix. Microbial qualities were influenced by THT; with 60s long enough to achieve stable products. PCA cluster analysis further emphasized variety as the most quality-determining factor in mango juice.
Organized meals for different groups - students, servicemen, employees working in specific businesses and organization of work - is invariably care for people’s health. An important task in this process is the preparation of menu plans that correspond to the norms for full, balanced and healthy nutrition for the respective age group and working conditions. They must provide the energy and nutrients necessary for the organism - proteins, carbohydrates, vitamins, fats (of animal and plant origin), etc. In some cases, menu planning must be consistent with the use of available food products or the use of interchangeable or similar foods. Problems arise when it comes to assessment and proving compliance with the quality and quantity standards of the products in the weekly menu plan. A commonly used solution is through the formal substitution of food products from the menu plan with the basic products defined by the norms. The mathematical model we offer creates an optimal solution that leaves minimal quantities of unchanged products.