Abstract: A wavelength-selective optical reception device includes a photoreceptor (21) that converts optical signals (201) into electric signals and outputs the electric signals, a base (31) on which the photoreceptor (21) is provided, a housing (41) that is mounted on the base (31) and surrounds the photoreceptor (21) along with the base (31), and that is provided with a window (51) to pass optical signals (203) including the optical signals (201) and including optical signals (202) of a wavelength different from a first wavelength of the optical signals (201) and a window (52) to pass the optical signals (202), and an optical filter (61) that is disposed inside the housing between the window (51) and the photoreceptor (21) along the optical axis (205) of the optical signals (203), and that outputs, out of the optical signals (203) that enter thereto, the optical signals (201) toward the photoreceptor (21), and reflects the optical signals (202) toward a near side in a direction of travel of the optical signals (203)

Abstract: Disclosed is an antiseptic agent for food and drink, which comprises, as an effective ingredient, a pectin decomposition product having a molecular weight of 600 to 5000. This antiseptic agent is very effective for improving the preservability of food and drink. If at least one member selected from the group consisting of ethanol, glycine, sodium acetate, ascorbic acid, sodium ascorbate, glycerin fatty acid esters, sodium chloride and ethylenediaminetetraacetic acid salts is used in combination with this antiseptic agent, its antifungal activity can further be enhanced.