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Ripening Period (ripening + period)
Selected AbstractsX-ray images for the control of eye formation in cheeseINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2009H KRAGGERUD There is demand for non-destructive monitoring of eye formation in cheese during ripening. The objective of this work was to develop a simple method based on existing equipment in the dairy industry. Images were acquired using a conventional, low resolution online X-ray instrument. Image processing methods for detecting eyes of cheese and measuring volume and size distribution were developed. Sufficient detection of overlapping eyes was obtained. Semihard cheese with propionibacteria ripened under different conditions was analysed. The method was found promising for quality control as it will make possible non-destructive monitoring of eye formation of cheese throughout the ripening period. [source] Ripening of traditional Örgü cheese manufactured with raw or pasteurized milk: Composition and biochemical propertiesINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 4 2007SERAFETTIN CELIK The changes in composition and some biochemical properties of Örgü cheeses made from raw (RMC) and pasteurized (PMC) cow milk were investigated during a 90-day ripening period. The average contents of total solids (TS), protein, water soluble nitrogen (WSN), trichloro-acetic acid soluble nitrogen (TCA-SN) and acid degree value (ADV) were lower, while salt and salt in TS were found to be statistically higher in PMC than RMC (P < 0.05). In addition, in both RMC and PMC, the TS and protein contents were decreased as compared to an increase in salt, salt in TS, WSN and TCA-SN contents, and ADV, during ripening (P < 0.05). The evaluation of WSN, TCA-SN and ADV shows that these two experimental Örgü cheese types undergo little proteolysis and lipolysis. On the other hand, acidity development was observed to be high in both before curdling and in cheese made from raw milk during ripening. [source] DETERMINATION OF pH CHANGE KINETICS DURING DIFFERENT STAGES OF KASHAR CHEESE MANUFACTURING FROM RAW AND PASTEURIZED MILK WITH ADDITION OF THERMOPHILIC, MESOPHILIC AND MIXED THERMOPHILIC CULTUREJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2008AHMET FERIT ATASOY ABSTRACT The pH change kinetics during Kashar cheese production from raw and pasteurized milk with addition of thermophilic, mesophilic and mixed thermophilic-mesophilic lactic acid bacteria were evaluated. The kinetics of pH change were determined during milk ripening, cooking/holding and pressing/fermentation phases of Kashar cheese. The pH decreased logarithmically, nonlinearly, with time in the milk ripening period, and reduced linearly with time in the cooking/holding and pressing/fermentation stages. Pasteurization of milk retarded the rate of change in pH during the three periods. The highest rate of pH change was determined in the addition of thermophilic culture, followed by mixed thermophilic-mesophilic and then mesophilic ones during milk ripening. The pH change characteristics of cheese made with thermophilic starter were similar to the cheese made with mixed thermophilic-mesophilic culture, but different from mesophilic lactic acid bacteria during cooking/holding and pressing/fermentation stages. PRACTICAL APPLICATIONS One of the important factors in the control of cheese quality is the extent of acid production in the vat. Acid development at a desired rate is important during cheese making. The progress of acidification is monitored by pH change in the industrial Kashar cheese production. Three main stages have been recognized with respect to pH change: milk ripening, cooking/holding and pressing/fermentation. This study evaluated and compared the pH change kinetics during various stages of Kashar cheese making using raw, pasteurized milk with the addition of thermophilic, mesophilic and mixed thermophilic culture. This work may help in the comparison of raw and pasteurized milk, and in the selection of appropriate starter culture for Kashar cheese production. [source] Investigation of the effect of sumac extract and BHT addition on the quality of sucuk (Turkish dry-fermented sausage)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2006Hüseyin Bozkurt Abstract The effect of sumac extract and BHT (butylated hydroxytoluene) addition on the quality (pH, colour, biogenic amine, TBARS values and sensory attributes) of sucuk (Turkish dry-fermented sausage) were investigated during the ripening period. Addition of BHT decreased the TBARS value by about 23.7%, whereas sumac extract decreased it by 42.0%. Sumac extract decreased (P < 0.05) putrescine formation more than BHT addition. However, no significant difference (P > 0.05) was observed in histamine formation for both the sumac extract and BHT-added recipe. The highest tyramine concentration was observed in a control recipe (R1) prepared without any antioxidants, and the lowest was in the sumac extract-added recipe (R3) with mean values of about 96.62 and 63.17 mg kg,1, respectively. The control recipe (R1) was found to be the worst (P < 0.05) sample with respect to overall sensory quality and addition of either sumac extract or BHT increased (P < 0.05) the overall sensory quality of sucuk. The pH and colour attributes of sucuk were not significantly different (P > 0.05) between the addition of sumac extract and BHT. This study demonstrated that sumac extract had more effect on the quality of sucuk during the ripening period, hence it could be easily utilised in sucuk to enhance quality. Copyright © 2006 Society of Chemical Industry [source] Study of the effect of ripening stages and climatic conditions on the physicochemical and sensorial parameters of two varieties of Vitis vinifera L. by principal component analysis: influence on enzymatic browningJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2006M Serrano-Megías Abstract The present paper describes the effects of maturation on the physicochemical, biochemical and color components of Napoleon and Dominga grape varieties, and on any differences between them. Climatic conditions were taken into account to explain the results obtained. Protein levels increased during ripening and were correlated with pH. Polyphenoloxidase activity was affected by climatic conditions (rainfall) and increased to a greater degree in Dominga than in Napoleon. Taste tests were conducted to determine the contribution of physicochemical and biochemical parameters to the sensorial properties of the grapes. Principal components analysis showed that parameters were correlated in different ways during the ripening period in Napoleon and Dominga varieties. In Dominga AE were correlated to the b parameter and in Napoleon to the L parameter. Copyright © 2005 Society of Chemical Industry [source] Effect of the fungal protease EPg222 on proteolysis and texture in the dry fermented sausage ,salchichón'JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2005María J Benito Abstract Proteolytic activity of the fungal protease EPg222 and its effect on the texture of the dry fermented sausage ,salchichón', which has a long ripening process, was assayed. Samples with enzyme added showed a significant reduction of myofibrillar protein concentration during the ripening period, compared with a control, and proteolytic activity of the enzyme led to a higher accumulation of non-protein and -amino acid nitrogen. Analysis of volatile compounds in ripened dry fermented sausages revealed that only in EPg222 batches were branched compounds derived from amino acids catabolism detected that are associated with the flavour of dry cured meat products. The texture profile analysis showed reduction in hardness, gumminess and chewiness values in treated compared with control sausages. The effect of this enzyme could be of great interest in stimulating proteolysis, in flavour development and in reducing the hardness of dry fermented sausages produced by a long ripening process. Copyright © 2004 Society of Chemical Industry [source] Effects of environmental factors and agricultural techniques on antioxidantcontent of tomatoesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2003Yvon Dumas Abstract Antioxidants are believed to be important in the prevention of diseases such as cancer and cardiovascular disease. Lycopene is one of the main antioxidants to be found in fresh tomatoes and processed tomato products. The lycopene content also accounts for the redness of the fruit, which is one of the main qualities for which industry and consumers now look. Other carotenes (such as ,-carotene), vitamin C, vitamin E and various phenolic compounds are also thought to be health-promoting factors with antioxidant properties. Since the antioxidant content of tomatoes may depend on genetic factors, the choice of variety cultivated may affect the results at harvest. To be able to control the antioxidant content of tomatoes at the field level when growing a given variety, it is necessary to know the effects of both environmental factors and the agricultural techniques used. Temperatures below 12 °C strongly inhibit lycopene biosynthesis and temperatures above 32 °C stop this process altogether. The effects of the temperature on the synthesis of other antioxidants have not yet been properly assessed. The effects of light have been studied more thoroughly, apart from those on vitamin E. The effects of water availability, mineral nutrients (nitrogen, phosphorus, potassium and calcium) and plant growth regulators have been studied, but results are sometimes contradictory and the data often incomplete. During the ripening period, lycopene content of tomatoes increases sharply from the pink stage onwards, but no sufficient attempts have been made so far to assess the changes in the other antioxidants present in the fruit. This paper reviews the present state of the art. Copyright © 2003 Society of Chemical Industry [source] Assimilate transport in grapevines -effect of phloem disruptionAUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2001J.J.(KOBUS) HUNTER Abstract Assimilate translocation in mature grapevines (cv. Gewürztraminer and cv. Harslevelü) under field conditions was investigated during the growth season by quantifying individual sugars and organic acids in mature leaves, shoot bark and berries, as affected by girdling the shoot just above the bunches. Tissue was sampled at berry set, pea size, veraison and ripeness stages of the vine. Invertase activity was determined in the shoot bark at ripeness. In the leaves, malic acid concentrations reached lowest levels at pea size, but increased thereafter. Tartaric acid decreased after peaking at pea size stage. Tartaric acid concentrations increased with girdling. Despite the increase in leaf age, sucrose concentrations remained virtually stable during the season, emphasising the importance of mature leaves for nourishing bunches. Girdling resulted in a build-up of sucrose in the leaves. In the bark, malic and tartaric acid stayed more or less the same during the growth period, but increased above the girdle. As a result of phloem disruption, sucrose also increased. The increase in glucose and tartaric acid is believed to result from catabolic cleavage of sucrose by invertase. Invertase activity was evident in the bark (of mature Harslevelü vines) at ripeness, which may indicate involvement in osmotic adjustments and gradients in the bark/phloem structure. In the berries, malic and tartaric acids reached peak concentrations at pea size. The volume increase during the ripening period, and in the case of malic acid also respiratory loss, resulted in a decrease in organic acid concentration. Malic acid continued to decrease after the initial decline, whereas tartaric acid stayed virtually stable. Girdling had no marked effect on organic acid accumulation in the berries. Sucrose concentrations were low during the first part of the season, but increased thereafter. Sucrose concentrations during ripening increased with girdling, which may represent a concentration effect and/or import from the rest of the vine. Sucrose concentrations (in mature Harslevelü vines) were indeed lower below than above the girdle. Comparison of sucrose concentrations in the leaves, bark and berries showed the existence of a decreasing concentration gradient, in line with the source:sink transport concept. An equally prominent decrease in sucrose:glucose ratio in the berries from the start of the ripening period indicates that vacuolar integrity (compartmentation) was affected in the ripening berry, most probably allowing hydrolysis of sucrose by invertase and decreasing osmotic potential within the berry. The results provide further evidence for the hypothesis of an osmotic gradient driven transport to the berry. [source] The effects of starter culture on chemical composition, microbiological and sensory characteristics of Turkish Ka,ar Cheese during ripeningINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 4 2007DURMU Ka,ar cheese samples were produced from raw milk and starter culture-added pasteurized milk. Chemical, microbiological and organoleptic properties of ka,ar cheeses were analysed at certain times during the ripening periods (on the 1st, 7th, 15th, 30th, 60th, 90th days). Generally, chemical parameters were not affected by starter culture. The pH, ripening index, water-soluble nitrogen and non-protein nitrogen did not show significant differences between the cheese samples. The addition of starter affected the microbiological quality of the cheeses. Starter culture-added ka,ar cheeses contained low levels of total aerobic mesophilic bacteria, moulds and yeasts, and coliforms, and achieved higher organoleptic scores than those of cheeses made from raw milk. The starter cultures contributed to acidity and microbial quality of the cheese. [source] | ||||||||||