Apple sugar contents

Joshi and Sandhu (2000) have described the production of an apple vermouth with different ethanol concentrations (12%, 15%, and 18%), sugar contents (4% and 8%), and spice extracts (2.5% and 5.0%). These variables significantly influence their respective sensory qualities. Spices extract levels did not, however, affect TSS (°Brix), titratable acidity, color,... 

The influence of alcohol and sugar content in the composition of apple vermouth are shown in Tables 8.9 and 8.10, respectively. 

Table I. Neutral sugar composition of pectins extracted from ripe and unripe apples (AIS). The capitals A-E refer to Fig. 2. The neutral sugar composition is expressed as moles sugar per mole arabinose. The values are averages of those for pectins with about the same neutral sugar content in the four extracts. Mannose was absent in all cases (1).

Low-methoxyl pectinates precipitated by calcium were compared with like pectinates precipitated by alcohol. All the pectinates were prepared by a simultaneous acid extraction and demethylation of pectins from apple pomace at 60 C. Calcium pectinates were of higher grade but lower in yield than alcohol-precipitated pectinates prepared under comparable conditions on the basis of 65% soluble solids. Alcohol coprecipitates materials other than pectin, which act as diluents, increasing the apparent yield of the alcohol-precipitated pectinates and lowering their grades. Demethylation increased with time of treatment and acidity. The calcium-precipitated pectinates were purer, as denoted by the calcium pectate content. The calcium pectinates were studied primarily for their use in gels of low sugar content. 

In some instances crop plants were also selected for a higher content of certain types of secondary products. Cultivated apples, pears and other fruits have a better aroma, i.e., contain more volatile secondary substances, and in addition to a higher sugar content are much more attractively colored than their wild progenitors. The pigments (E 5.5.2) and scent volatiles are usually nontoxic for humans, in contrast, for example, to the tanning substances which many of the wild forms of our cultivated fruits contain. 

An attempt was made to find robust calibration equations for sugar content and acidity by MLR, PCR, and PLS, where the optical parameters were employed as explanatory variables. Normally, chemometrics by NIR spectra employs the absorbance as the explanatory variable, where only wavelength-dependent characteristics of the materials can be considered. In this case, it is very difficult to precisely evaluate the small amount of a constituent such as acid content in a fruit. On the other hand, chemometrics by TOF-NIRS would be related to both wavelength- and time-dependent characteristics as the explanatory variables, where the light absorption and light scattering phenomena in a sample are included. It may therefore be possible to detect the acid content in a fruit on the basis of this new optical concept. The statistical results are summarized in Tables 4.2.1 and 4.2.2. Figure 4.2.9 shows the PLS analysis in a optimum model for acidity in apple. In the case of normal analysis by second-derivative NIR spectra, standard error of calibration (SEC) and correlation coefficient between measured and predicted acidity r were limited to 0.048% and... 

S. Tsuchikawa, T. Hamada. Application of time-of-flight near infrared spectroscopy for detecting sugar content and acidity in apples. NIR News 14 6-8, 2003. 

As a result of structural similarities, MCP docks on to receptor proteins for ethylene, causing it to lose activity. The texture and color of apples and pears (sensitive varieties) do not change through months of cool storage. The sugar content also remains constant while the acid content increases. Gaseous MCP adsorbed on dextran is used for the treatment of fruit. The MCP is liberated by the addition of water. The concentrations applied are in the range 300-1000 ppb. 

In many cases, HSI may replace NIR spectrometers to compute concentrations of various compounds or to estimate quality parameters of agricultural and food products. HSI can be used to assess properties as diverse as oil content, moisture, flour yield, softness, sucrose solvent retention capacity, and alpha-amylase activity in grains [26-28] sugar content and maturity of fruits like apple or banana [29-31] drip loss, water-holding capacity, color, pH, and sensory properties of meat [32-39] analysis of mixtures to detect the presence of substances such as, in forages [40], or the concentration of n-3 polyunsaturated fatty acids in designer eggs [41]. 

Zhao, J. etal. (2009) Nondestructive measurement of sugar content of apple using hyperspectral imaging technique. Maejo Int. J. Scl Technol, 3 (1), 130-142. 

In most markets fmit juice must be 100% juice and contain no additives. Fmit nectars consist of pulp, juice, sugar, and water, and contain from 25 to 50% juice, depending on the fmit used. In the EEC the minimum juice content is 50% for orange and apple, 40% for apricot, and 25% for passion fmit and guava (26). Other fmit juice drinks include cocktails, which usually contain at least 25% juice and a variety of juice drinks which can contain from 1.5—70% juice (Table 2). 

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