Ten Bacteroides species found in the human colon were surveyed for their ability to ferment mucins and plant polysaccharides ("dietary fiber"). A number of strains fermented mucopolysaccharides (heparin, hyaluronate, and chondroitin sulfate) and ovomucoid. Only 3 of the 188 strains tested fermented beef submaxillary mucin, and none fermented porcine gastric mucin. Many of the Bacteroides strains tested were also able to ferment a variety of plant polysaccharides, including amylose, dextran, pectin, gum tragacanth, gum guar, larch arabinogalactan, alginate, and laminarin. Some plant polysaccharides, such as gum arabic, gum karaya, gum ghatti, and fucoidan, were not utilized by any of the strains tested. The ability to utilize mucins and plant polysaccharides varied considerably among the Bacteroides species tested.

A total of 154 strains from 22 species of Bifidobacterium, Peptostreptococcus, Lactobacillus, Ruminococcus, Coprococcus, Eubacterium, and Fusobacterium, which are present in high concentrations in the human colon, were surveyed for their ability to ferment 21 different complex carbohydrates. Plant polysaccharides, including amylose, amylopectin, pectin, polygalacturonate, xylan, laminarin, guar gum, locust bean gum, gum ghatti, gum arabic, and gum tragacanth, were fermented by some strains from Bifidobacterium, Peptostreptococcus, Ruminococcus, and Eubacterium species. Porcine gastric mucin, which was fermented by some strains of Ruminococcus torques and Bifidobacterium bifidum, was the only mucin utilized by any of the strains tested.

ABSTRACT. A lexicon of terms to describe desirable as well as undesirable flavors in peanuts has been developed. The lexicon and an intensity rating scale was developed by a 13 member panel of flavor and peanut specialists representing industry and the USDA‐Agricultural Research Service. This system is intended to provide definitive, common terminology for use in communicating differences in peanut flavor variables among all phases of peanut research and industry.

Florunner peanuts from five, pod-color based, maturity classes from 1985 and 1986 crop years were screened to obtain uniform sized kernels for roast color and descriptive flavor analyses. Maturity classes were roasted to the same Hunter L value (50 2 1) using variable roast times or roasted for the same time wherein Hunter L values increased as maturity increased. Sensory evaluation of both roast methods suggested a trend for increased intensity of "on" flavor descriptors such as roasted peanutty and sweet aromatic as peanuts mature. Intensities of "off" flavor descriptors such as painty and fruity fermented were higher in immature peanuts. Intensities of several descriptors were affected by moderate handling differences between the two crop years.

Thermal degradation of pure sucrose in concentrated aqueous solution (100 °C, ∼65 °Brix) in the presence of KCl, LiCl, NaI, and Na2B4O7 was investigated. Polarimetry was used to quantify sucrose degradation, and pseudo-first-order kinetic constants of initial degradation rates were calculated. All salts significantly increased sucrose degradation; colored degradation products were only formed in the presence of Na2B4O7. Thermal degradation characteristics of crystalline sucrose and dried, crystalline residues from sucrose−salt model solutions heated at 100 °C for 0 and 3 h were further investigated by differential scanning calorimetry (DSC), thermogravimetric (TG), and differential thermogravimetric (DTG) analyses. Rate of heating was 15 °C/min from 50 to 500 °C. DSC and TG studies confirmed the catalytic nature of salts on the thermal degradation of sucrose. Salts affected thermal degradation in various ways. The initial condensation degradation reactions were more rapid than expected, and subsequent elimination reactions were slower. The thermal analysis results indicate that complexation between the salt and sucrose is occurring, and further study at the molecular level is required. Keywords: Sucrose thermal degradation; DSC; TG, DTG; salts; crystalline sucrose; amorphous sucrose

Windrow dried peanuts were separated into five, pod-mescarp colorbased maturity classes and mechanically cured with three temperature regimes. Temperature treatments used in the commercial drying operation were ambient air [maximum XX), ambient +8.4"C increase, and ambient + 16.8"C increase, A panel trained in peanut flavor descriptive analysis evaluated peanuts of similar size and roast color from each maturity stage. Intensity ratings of descriptors roasted peanutty and sweet aromatic were lowest and ratings for fruity fcrmentcd, painty, sour, and bitter were highest for immature peanuts cured at the higher temperatures.

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