Peaches freezing

It is well known that the Maillard reaction in foods is initiated by the formation of colorless and tasteless intermediates, which preferentially are formed in low-moisture systems ( ,5.). In this way by reaction of glucose with amino acids fructose-amino acids are formed via Amadori rearrangement of the primary glucosyl-ami-no acids (1 ). Fructose-amino acids e.g. have been isolated from freeze-dried apricots and peaches ( 6,7,8j. Amadori compounds arising from aldoses and amino acids are formed during drying of foods of plant origin and can be easily detected by amino acid analysis (j>). 

As and DMA were found to be the main species in rice-based and mixed rice/formula cereals, although traces of MM A were also detected. Inorganic As was present in freeze-dried sweet potatoes, carrots, green beans, and peaches. MM A and DMA were not detected in these samples [29]. 

HPSF has also been applied in the processing of fruits, pork, lobster, and tofu. Martino et al. (1998) observed that a uniform and instantaneous ice nucleation within the whole volume of a pork sample was achieved only by HPSF when compared to classical freezing methods. Otero et al. (2000) confirmed the beneficial effects of HPSF on whole peach and mango as compared to air-blast frozen samples. 

Otero, L., Martino, M., Zaritzky, N., Solas, M., and Sanz, P.D. 2000. Preservation of microstructure in peach and mango during high-pressure-shift freezing. Journal of Food Science 65(3) 466 70. 

Synonyms Cyanoethylene, Fumigrain, Ventox, Vinyl Cyanide Chemical Formula CH2=CHCN (ii) Observable Characteristics — Physical State (as normally shipped) Liquid Color Colorless Odor Mild pungent, resembling that of peach seed kernels (iii) Physical and Chemical Properties — Physical State at 15 G and I am. Liquid Molecular Weight 53.06 Boiling Point at I am. 171,77.4, 350.6 Freezing Point -118, -83.6, 189.6 Critical Temperature ("F, "K) 505, 263, 536 Critical Pressure 660, 45, 4.6 Specific Gravity 0.8075 at 20°C (liquid) Vapor (Gas) Density 1.8 Ratio of Specific Heats of Vapor (Gas) 1.151 Latent Heat of Vaporization 265, 147, 6.16 Heat of Combustion -14,300, -7930, -332 Heat of... 

Freezing— The vitamin contents of eight common frozen fruit products (apples, apricots, blueberries, cherries, orange juice concentrate, peaches, raspberries, and strawberries) were found to be lower than those of their fresh counterparts, but higher than those of canned fruit products.This study showed that the average vitamin losses were as follows vitamin A, 37% vitamin B-1 (thiamin), 29% vitamin B-2 (riboflavin), 17% niacin, 15% and vitamin C, 18%. 

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