Effect of blending Jersey and Holstein-Friesian milk on Cheddar cheese processing, composition and quality

The effect of Jersey milk use solely or at different inclusion rates in Holstein-Friesian milk on Cheddar cheese production was investigated. Cheese was produced every month over a year using nonstandardized milk consisting of 0, 25, 50, 75, and 100% Jersey milk in Holstein-Friesian milk in a 100-L vat. Actual, theoretical, and moisture-adjusted yield increased linearly with percentage of Jersey milk. This was also associated with increased fat and protein recoveries and lower yield of whey. The composition of whey was also affected by the percentage of Jersey milk, with lower whey protein and higher whey lactose and solids. Cutting time was lower when Jersey milk was used, but the cutting to milling time was higher because of slower acidity development. Hence, overall cheesemaking time was not affected by the use of Jersey milk. Using Jersey milk increased cheese fat content in autumn, winter, and spring and decreased cheese moisture in spring and summer. Cheese protein, salt, and pH levels were not affected. Cheese was analyzed for texture and color, and it was professionally graded at 3 and 8 mo. The effect of Jersey on cheese sensory quality was an increase in cheese yellowness during summer and a higher total grading score at 3 mo in winter; no other difference in cheese quality was found. The study indicates that using Jersey milk is a valid method of improving Cheddar cheese yield

A possible rheological model of gum candies

An appropriate rheological model can be used in production of good quality gum candy required by consumers. For this purpose Creep-Recovery Test (CRT) curves were recorded with a Stable Micro System TA.XT-2 precision texture analyser with 75 mm diameter cylinder probe on gum candies purchased from the local market. The deformation speed was 0.2 mm s−1, the creeping- and recovering time was 60 s, while the loading force was set to 1 N, 2 N, 5 N, 7 N, and 10 N. The two-element Kelvin-Voigt-model, a three-element model, and the four-element Burgers-model were fitted on the recorded creep data, and then the parameters of the models were evaluated. The best fitting from the used models was given by the Burgers model

Strawberry fruit resistance to simulated handling

Harvest operations are currently the main source of mechanical injury of strawberry (Fragaria x ananassa Duch.). Experiments were designed to simulate conditions encountered during commercial handling. Individual fruits were subjected to impact or compression forces with similar energy to determine the sensitivity to mechanical injury. Bruise volume was used as the measurement of injury. Bruise severity increased as a function of impact energy for both impact types. However, dropped fruits had larger bruise volume than fruits submitted to pendulum impactor at the same energy level. Doubling the impact energy (0.040 to 0.083 J) increased bruise volume by 7 times (13 to 91 mm³). Fruits dropped from 380 mm (0.075 J) showed 71% greater bruise volume than those dropped from either 130 mm (0.025 J) or 200 mm (0.040 J). Compressed fruits showed higher bruise volume than other tests. Some cultivars are more susceptible to compression forces than others. 'Sweet Charlie' berries showed bruise volume 40% higher than the others cultivars when subjected to compression. Fruits subjected to impact showed bruise volume lower than the compressed fruits, indicating the possibility to be handled and graded in a packing line.A etapa de colheita é a principal fonte de danos físicos ao morango (Fragaria x ananassa Duch.). Experimentos foram realizados para simular condições encontradas durante manuseio. Frutos foram submetidos individualmente às forças de impacto e compressão em energias similares para determinar sensibilidade dos frutos a danos físicos. Volume da injúria física foi utilizado para mensurar a incidência do dano físico ocorrido. Severidade da lesão aumenta, com incremento da energia, tanto para força de impacto como para compressão. Todavia, frutos submetidos à queda livre demonstraram maiores volumes de danos físicos do que frutos submetidos a danos ocasionados por pendulo no mesmo nível de energia. Dobrando a energia de impacto (0,040 para 0,083 J) ocorreu aumento no volume da injúria em sete vezes (13 para 91 mm³). Frutos submetidos à queda de 380 mm (0,075 J) demonstraram volumes de danos físicos 71% superiores do que aqueles ocasionados em queda de 130 mm (0,025 J) ou 200 mm (0,040 J). Frutos em teste de compressão mostraram maiores volumes de injúrias físicas do que outros testes. Alguns cultivares são mais sensíveis à força de compressão do que outros. Frutos cultivar 'Sweet Charlie' apresentaram volume de injúria 40% superiores do que outros quando submetidos à força de compressão. Morangos submetidos à força de impacto demonstraram volume de injúria inferior do que aqueles comprimidos, indicando a possibilidade dos morangos serem classificados e manuseados em uma linha de beneficiamento