Thermal Sensitivity of Neosartorya fischeri Ascospores in Regular and Reduced-Sugar Grape Jelly

A study was conducted to determine the thermal sensitivity of Neosartorya fischeri ascospores in regular (standard) and reduced-sugar formulas of Concord grape jelly. Ascospores were inactivated more rapidly by heating in the reduced-sugar formula than in the regular formula. Protection against inactivation in the regular formula may be due to its having a higher pH (3.27) than the pH (3.14) of the reduced-sugar formula. The lower aw (0.78) of the regular jelly formula compared to that of the reduced-sugar formula (aw, 0.82) would also protect against thermal inactivation. These results demonstrate the need to consider the efficacy of thermal processing schemes in achieving desired levels of sterility when changes are made in product formulas.

Polarographic Determination of Fumaric Acid in Foods

The previously reported polarographic method for determining fumaric acid in foods has been revised and subjected to collaborative study. Interferences from naturally occurring substances were kept to a minimum by using a 25.00 g sample of juices. Seven types of samples were sent to collaborators: grape jelly (0.10% added fumaric acid) and apple, lemon, orange, pineapple, sauerkraut, and tomato juices with 0.05, 0.10, and 0.50% added fumaric acid. Analysis at the 0.05 and 0.10% levels indicated a 95 % confidence limit of ± 0.003 about the means 0.05 and 0.10, respectively, while results from the 0.50% level indicated ± 0.01 about its mean of 0.48. It is recommended that the method be adopted as official, first action.

PREPARATION OF IRISH MOSS EXTRACTS FOR USE AS A JELLING AND STABILIZING AGENT IN FOODS

Bleached Irish moss suspended on 40-mesh screens was extracted three times with water at 212° F. (100 °C). The second and third extracts were used for extracting fresh batches and by this method solutions containing 1.5 to 1.8% solids were obtained. One percent of activated charcoal mixed with the solution by agitation with air for one-half hour adsorbed all detectable flavours and odours and most of the pigment. The charcoal and suspended plant particles were removed simultaneously by filtration at 50 to 60 lb. pressure with diatomaceous earth of relatively large particle size. Potassium chloride (0.5 gm. per 100 ml.) was added to the hot filtrate, which was then poured into galvanized iron trays allowed to gel, and frozen in air at 10° F. (− 12 °C). The ice was separated mechanically from the contracted sheet of jelly, which lost on the average 90% of the water. At room temperature the rubber-like contracted sheet of jelly was dried by means of a fan, to a residual moisture content of 8 to 10% in about two hours. The dried sheet was coarsely ground in a Wiley mill.The resulting product employed in jellied canned chicken was preferred to an agar-agar pack by a consumer's taste panel. In grape jelly it was not a complete substitute for pectin but was considered acceptable as a fruit jelly. In three standard desserts it was not as desirable as gelatine but was considered acceptable as a jellied dessert. The material was effective in stabilizing chocolate milk in the same concentration as a commercial product now on the market.